diff --git a/.gitignore b/.gitignore
index b33ad04..2c0bb40 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ cdi4dc
 tools/ttf_outline
 *.blend1
 *.scramble
+*.FCStd1
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 108c2ed..c777550 100644
--- a/Makefile
+++ b/Makefile
@@ -17,6 +17,7 @@ build-fonts:
 	./tools/ttf_outline 20 7f 20 1 little /usr/share/fonts/terminus/ter-u20n.otb ter_u20n.data
 
 include example/example.mk
+include chess/chess.mk
 include text_editor/text_editor.mk
 include snake/snake.mk
 include pokemon/pokemon.mk
diff --git a/chess/bishop.blend b/chess/bishop.blend
new file mode 100644
index 0000000..b52298c
Binary files /dev/null and b/chess/bishop.blend differ
diff --git a/chess/bishop.hpp b/chess/bishop.hpp
new file mode 100644
index 0000000..139be85
--- /dev/null
+++ b/chess/bishop.hpp
@@ -0,0 +1,186 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace bishop {
+  constexpr vec3 vertices[] = {
+    {  0.584650f, -0.818375f, -0.500000f },
+    {  0.529532f, -0.513422f, -0.500000f },
+    {  0.563451f, -0.571720f, -0.500000f },
+    {  0.583590f, -0.676656f, -0.500000f },
+    {  0.443675f, -0.462544f, -0.500000f },
+    {  0.334500f, -0.438165f, -0.500000f },
+    {  0.407043f, -0.320535f, -0.500000f },
+    {  0.463823f, -0.189392f, -0.500000f },
+    {  0.479209f, -0.023082f, -0.500000f },
+    {  0.452467f,  0.148357f, -0.500000f },
+    {  0.382133f,  0.302579f, -0.500000f },
+    {  0.280853f,  0.429180f, -0.500000f },
+    {  0.178835f,  0.531712f, -0.500000f },
+    {  0.132904f,  0.457515f, -0.500000f },
+    {  0.092272f,  0.362119f, -0.500000f },
+    {  0.059590f,  0.230507f, -0.500000f },
+    {  0.039274f,  0.091829f, -0.500000f },
+    {  0.035741f, -0.005334f, -0.500000f },
+    { -0.054356f, -0.005334f, -0.500000f },
+    { -0.049939f,  0.075929f, -0.500000f },
+    { -0.036690f,  0.184575f, -0.500000f },
+    { -0.014607f,  0.311770f, -0.500000f },
+    {  0.024258f,  0.435432f, -0.500000f },
+    {  0.061357f,  0.532595f, -0.500000f },
+    {  0.117888f,  0.611209f, -0.500000f },
+    {  0.156753f,  0.654491f, -0.500000f },
+    {  0.143503f,  0.726038f, -0.500000f },
+    {  0.102872f,  0.784336f, -0.500000f },
+    {  0.026025f,  0.832034f, -0.500000f },
+    { -0.054356f,  0.837334f, -0.500000f },
+    { -0.129436f,  0.807302f, -0.500000f },
+    { -0.187734f,  0.742821f, -0.500000f },
+    { -0.207167f,  0.660674f, -0.500000f },
+    { -0.174484f,  0.571460f, -0.500000f },
+    { -0.290197f,  0.458398f, -0.500000f },
+    { -0.398335f,  0.315972f, -0.500000f },
+    { -0.482736f,  0.141896f, -0.500000f },
+    { -0.511748f, -0.037456f, -0.500000f },
+    { -0.491674f, -0.191457f, -0.500000f },
+    { -0.437898f, -0.324945f, -0.500000f },
+    { -0.365704f, -0.436764f, -0.500000f },
+    { -0.455874f, -0.460073f, -0.500000f },
+    { -0.517828f, -0.487063f, -0.500000f },
+    { -0.577941f, -0.546563f, -0.500000f },
+    { -0.600052f, -0.670555f, -0.500000f },
+    { -0.604886f, -0.818375f, -0.500000f },
+    {  0.411411f, -0.543957f, -1.500000f },
+    {  0.180380f, -0.452089f, -1.500000f },
+    {  0.466089f, -0.576359f, -1.500000f },
+    {  0.481290f, -0.602485f, -1.500000f },
+    {  0.497165f, -0.685202f, -1.500000f },
+    {  0.501751f, -0.748000f, -1.500000f },
+    {  0.325265f, -0.291323f, -1.500000f },
+    {  0.377679f, -0.177063f, -1.500000f },
+    {  0.392465f, -0.029934f, -1.500000f },
+    {  0.369663f,  0.120901f, -1.500000f },
+    {  0.308541f,  0.256122f, -1.500000f },
+    {  0.209282f,  0.388418f, -1.500000f },
+    {  0.174547f,  0.334577f, -1.500000f },
+    {  0.144549f,  0.213777f, -1.500000f },
+    {  0.125532f,  0.083966f, -1.500000f },
+    {  0.119140f, -0.091821f, -1.500000f },
+    { -0.145671f, -0.091821f, -1.500000f },
+    { -0.136141f,  0.083520f, -1.500000f },
+    { -0.122276f,  0.197215f, -1.500000f },
+    { -0.098837f,  0.332223f, -1.500000f },
+    { -0.057469f,  0.463849f, -1.500000f },
+    { -0.015428f,  0.573955f, -1.500000f },
+    {  0.058744f,  0.679341f, -1.500000f },
+    {  0.042113f,  0.720256f, -1.500000f },
+    { -0.001227f,  0.747156f, -1.500000f },
+    { -0.040460f,  0.749743f, -1.500000f },
+    { -0.078716f,  0.734440f, -1.500000f },
+    { -0.108683f,  0.701295f, -1.500000f },
+    { -0.117024f,  0.666037f, -1.500000f },
+    { -0.074035f,  0.548691f, -1.500000f },
+    { -0.225181f,  0.401007f, -1.500000f },
+    { -0.324259f,  0.270512f, -1.500000f },
+    { -0.399383f,  0.115571f, -1.500000f },
+    { -0.424164f, -0.037621f, -1.500000f },
+    { -0.407556f, -0.169668f, -1.500000f },
+    { -0.359987f, -0.286169f, -1.500000f },
+    { -0.228055f, -0.450233f, -1.500000f },
+    { -0.427604f, -0.542096f, -1.500000f },
+    { -0.468471f, -0.559899f, -1.500000f },
+    { -0.503422f, -0.594493f, -1.500000f },
+    { -0.513465f, -0.685691f, -1.500000f },
+    { -0.514719f, -0.748000f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{21}, {22}, {40}},
+    {{67}, {70}, {75}},
+    {{ 1}, { 4}, { 5}},
+    {{ 5}, { 6}, { 7}},
+    {{ 7}, { 8}, { 9}},
+    {{ 9}, {10}, {11}},
+    {{11}, {12}, {13}},
+    {{13}, {14}, {15}},
+    {{15}, {16}, {17}},
+    {{13}, {15}, {17}},
+    {{ 9}, {11}, {13}},
+    {{ 5}, { 7}, { 9}},
+    {{ 2}, { 1}, { 5}},
+    {{ 0}, { 3}, { 2}},
+    {{44}, {45}, { 0}},
+    {{42}, {43}, {44}},
+    {{40}, {41}, {42}},
+    {{38}, {39}, {40}},
+    {{36}, {37}, {38}},
+    {{34}, {35}, {36}},
+    {{31}, {32}, {33}},
+    {{33}, {34}, {36}},
+    {{36}, {38}, {40}},
+    {{40}, {42}, {44}},
+    {{44}, { 0}, { 2}},
+    {{ 5}, { 9}, {13}},
+    {{44}, { 2}, { 5}},
+    {{33}, {36}, {40}},
+    {{40}, {44}, { 5}},
+    {{ 5}, {13}, {17}},
+    {{ 5}, {17}, {18}},
+    {{30}, {31}, {33}},
+    {{28}, {29}, {30}},
+    {{26}, {27}, {28}},
+    {{24}, {25}, {26}},
+    {{23}, {24}, {26}},
+    {{26}, {28}, {30}},
+    {{30}, {33}, {40}},
+    {{40}, { 5}, {18}},
+    {{40}, {18}, {19}},
+    {{26}, {30}, {40}},
+    {{23}, {26}, {40}},
+    {{40}, {19}, {20}},
+    {{40}, {20}, {21}},
+    {{22}, {23}, {40}},
+    {{48}, {46}, {47}},
+    {{47}, {52}, {53}},
+    {{53}, {54}, {55}},
+    {{55}, {56}, {57}},
+    {{57}, {58}, {59}},
+    {{59}, {60}, {61}},
+    {{57}, {59}, {61}},
+    {{53}, {55}, {57}},
+    {{49}, {48}, {47}},
+    {{47}, {53}, {57}},
+    {{47}, {57}, {61}},
+    {{50}, {49}, {47}},
+    {{87}, {51}, {50}},
+    {{85}, {86}, {87}},
+    {{83}, {84}, {85}},
+    {{80}, {81}, {82}},
+    {{82}, {83}, {85}},
+    {{85}, {87}, {50}},
+    {{47}, {61}, {62}},
+    {{85}, {50}, {47}},
+    {{79}, {80}, {82}},
+    {{82}, {85}, {47}},
+    {{82}, {47}, {62}},
+    {{78}, {79}, {82}},
+    {{76}, {77}, {78}},
+    {{73}, {74}, {75}},
+    {{75}, {76}, {78}},
+    {{78}, {82}, {62}},
+    {{78}, {62}, {63}},
+    {{72}, {73}, {75}},
+    {{78}, {63}, {64}},
+    {{78}, {64}, {65}},
+    {{71}, {72}, {75}},
+    {{75}, {78}, {65}},
+    {{75}, {65}, {66}},
+    {{70}, {71}, {75}},
+    {{68}, {69}, {70}},
+    {{75}, {66}, {67}},
+    {{67}, {68}, {70}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/bishop.mtl b/chess/bishop.mtl
new file mode 100644
index 0000000..61df9cf
--- /dev/null
+++ b/chess/bishop.mtl
@@ -0,0 +1,2 @@
+# Blender 3.3.6 MTL File: 'bishop.blend'
+# www.blender.org
diff --git a/chess/bishop.obj b/chess/bishop.obj
new file mode 100644
index 0000000..f4b0ed9
--- /dev/null
+++ b/chess/bishop.obj
@@ -0,0 +1,176 @@
+# Blender 3.3.6
+# www.blender.org
+o Bishop
+v 0.584650 -0.818375 -0.500000
+v 0.529532 -0.513422 -0.500000
+v 0.563451 -0.571720 -0.500000
+v 0.583590 -0.676656 -0.500000
+v 0.443675 -0.462544 -0.500000
+v 0.334500 -0.438165 -0.500000
+v 0.407043 -0.320535 -0.500000
+v 0.463823 -0.189392 -0.500000
+v 0.479209 -0.023082 -0.500000
+v 0.452467 0.148357 -0.500000
+v 0.382133 0.302579 -0.500000
+v 0.280853 0.429180 -0.500000
+v 0.178835 0.531712 -0.500000
+v 0.132904 0.457515 -0.500000
+v 0.092272 0.362119 -0.500000
+v 0.059590 0.230507 -0.500000
+v 0.039274 0.091829 -0.500000
+v 0.035741 -0.005334 -0.500000
+v -0.054356 -0.005334 -0.500000
+v -0.049939 0.075929 -0.500000
+v -0.036690 0.184575 -0.500000
+v -0.014607 0.311770 -0.500000
+v 0.024258 0.435432 -0.500000
+v 0.061357 0.532595 -0.500000
+v 0.117888 0.611209 -0.500000
+v 0.156753 0.654491 -0.500000
+v 0.143503 0.726038 -0.500000
+v 0.102872 0.784336 -0.500000
+v 0.026025 0.832034 -0.500000
+v -0.054356 0.837334 -0.500000
+v -0.129436 0.807302 -0.500000
+v -0.187734 0.742821 -0.500000
+v -0.207167 0.660674 -0.500000
+v -0.174484 0.571460 -0.500000
+v -0.290197 0.458398 -0.500000
+v -0.398335 0.315972 -0.500000
+v -0.482736 0.141896 -0.500000
+v -0.511748 -0.037456 -0.500000
+v -0.491674 -0.191457 -0.500000
+v -0.437898 -0.324945 -0.500000
+v -0.365704 -0.436764 -0.500000
+v -0.455874 -0.460073 -0.500000
+v -0.517828 -0.487063 -0.500000
+v -0.577941 -0.546563 -0.500000
+v -0.600052 -0.670555 -0.500000
+v -0.604886 -0.818375 -0.500000
+v 0.411411 -0.543957 -1.500000
+v 0.180380 -0.452089 -1.500000
+v 0.466089 -0.576359 -1.500000
+v 0.481290 -0.602485 -1.500000
+v 0.497165 -0.685202 -1.500000
+v 0.501751 -0.748000 -1.500000
+v 0.325265 -0.291323 -1.500000
+v 0.377679 -0.177063 -1.500000
+v 0.392465 -0.029934 -1.500000
+v 0.369663 0.120901 -1.500000
+v 0.308541 0.256122 -1.500000
+v 0.209282 0.388418 -1.500000
+v 0.174547 0.334577 -1.500000
+v 0.144549 0.213777 -1.500000
+v 0.125532 0.083966 -1.500000
+v 0.119140 -0.091821 -1.500000
+v -0.145671 -0.091821 -1.500000
+v -0.136141 0.083520 -1.500000
+v -0.122276 0.197215 -1.500000
+v -0.098837 0.332223 -1.500000
+v -0.057469 0.463849 -1.500000
+v -0.015428 0.573955 -1.500000
+v 0.058744 0.679341 -1.500000
+v 0.042113 0.720256 -1.500000
+v -0.001227 0.747156 -1.500000
+v -0.040460 0.749743 -1.500000
+v -0.078716 0.734440 -1.500000
+v -0.108683 0.701295 -1.500000
+v -0.117024 0.666037 -1.500000
+v -0.074035 0.548691 -1.500000
+v -0.225181 0.401007 -1.500000
+v -0.324259 0.270512 -1.500000
+v -0.399383 0.115571 -1.500000
+v -0.424164 -0.037621 -1.500000
+v -0.407556 -0.169668 -1.500000
+v -0.359987 -0.286169 -1.500000
+v -0.228055 -0.450233 -1.500000
+v -0.427604 -0.542096 -1.500000
+v -0.468471 -0.559899 -1.500000
+v -0.503422 -0.594493 -1.500000
+v -0.513465 -0.685691 -1.500000
+v -0.514719 -0.748000 -1.500000
+s 0
+f 22 23 41
+f 68 71 76
+f 2 5 6
+f 6 7 8
+f 8 9 10
+f 10 11 12
+f 12 13 14
+f 14 15 16
+f 16 17 18
+f 14 16 18
+f 10 12 14
+f 6 8 10
+f 3 2 6
+f 1 4 3
+f 45 46 1
+f 43 44 45
+f 41 42 43
+f 39 40 41
+f 37 38 39
+f 35 36 37
+f 32 33 34
+f 34 35 37
+f 37 39 41
+f 41 43 45
+f 45 1 3
+f 6 10 14
+f 45 3 6
+f 34 37 41
+f 41 45 6
+f 6 14 18
+f 6 18 19
+f 31 32 34
+f 29 30 31
+f 27 28 29
+f 25 26 27
+f 24 25 27
+f 27 29 31
+f 31 34 41
+f 41 6 19
+f 41 19 20
+f 27 31 41
+f 24 27 41
+f 41 20 21
+f 41 21 22
+f 23 24 41
+f 49 47 48
+f 48 53 54
+f 54 55 56
+f 56 57 58
+f 58 59 60
+f 60 61 62
+f 58 60 62
+f 54 56 58
+f 50 49 48
+f 48 54 58
+f 48 58 62
+f 51 50 48
+f 88 52 51
+f 86 87 88
+f 84 85 86
+f 81 82 83
+f 83 84 86
+f 86 88 51
+f 48 62 63
+f 86 51 48
+f 80 81 83
+f 83 86 48
+f 83 48 63
+f 79 80 83
+f 77 78 79
+f 74 75 76
+f 76 77 79
+f 79 83 63
+f 79 63 64
+f 73 74 76
+f 79 64 65
+f 79 65 66
+f 72 73 76
+f 76 79 66
+f 76 66 67
+f 71 72 76
+f 69 70 71
+f 76 67 68
+f 68 69 71
diff --git a/chess/board.FCStd b/chess/board.FCStd
new file mode 100644
index 0000000..be21262
Binary files /dev/null and b/chess/board.FCStd differ
diff --git a/chess/chess.cpp b/chess/chess.cpp
new file mode 100644
index 0000000..2386b7f
--- /dev/null
+++ b/chess/chess.cpp
@@ -0,0 +1,446 @@
+#include <cstdint>
+
+#include "chess.hpp"
+#include "sh7091/serial.hpp"
+namespace chess {
+
+xy position_to_xy(int8_t position)
+{
+  int8_t y = (position >> 4) & 0xf;
+  int8_t x = (position >> 0) & 0xf;
+  return {x, y};
+}
+
+int8_t xy_to_position(int8_t x, int8_t y)
+{
+  return ((y & 0xf) << 4)
+       | ((x & 0xf) << 0);
+}
+
+bool xy_inside_board(int8_t x, int8_t y)
+{
+  int8_t position = xy_to_position(x, y);
+  return (position & 0x88) == 0;
+}
+
+int8_t piece_list_to_position(const chess::board_state& board_state,
+			      chess::piece * piece)
+{
+  int8_t position = piece - &board_state.board[0];
+  return position;
+}
+
+constexpr inline bool turn_same_side(int8_t side, int8_t type)
+{
+  return (type != 0) && ((side > 0) == (type > 0));
+}
+
+bool speculative_check(game_state& game_state, int8_t from_position, int8_t to_position, int8_t side);
+
+template <int max_limit>
+static move_t * moves_line(game_state& game_state, int8_t origin, move_t * moves, int dx, int dy)
+{
+  board_state& board = game_state.board;
+  piece& self = board.board[origin];
+  auto [ox, oy] = position_to_xy(origin);
+  int8_t x = ox, y = oy;
+  for (int limit = 0; limit < max_limit; limit++) {
+    x += dx;
+    y += dy;
+    if (xy_inside_board(x, y)) {
+      piece& other = board.board[xy_to_position(x, y)];
+      bool different_sides = ((self.type ^ other.type) < 0);
+      if (other.type == 0 || different_sides) {
+	int8_t to_position = xy_to_position(x, y);
+	if (!speculative_check(game_state, origin, to_position, self.type))
+	  *moves++ = {move_type::normal, to_position};
+      }
+      if (other.type != 0)
+	break;
+    } else {
+      break;
+    }
+  }
+  return moves;
+}
+
+move_t * moves_pawn(game_state& game_state, int8_t origin, move_t * moves)
+{
+  board_state& board = game_state.board;
+  piece& self = board.board[origin];
+  int8_t direction = (self.type > 0) ? 1 : -1;
+
+  auto [ox, oy] = position_to_xy(origin);
+  int advance = 1;
+  auto type = move_type::normal;
+  do {
+    int8_t x = ox;
+    int8_t y = oy + direction * advance;
+    if (xy_inside_board(x, y)) {
+      piece& other = board.board[xy_to_position(x, y)];
+      if (other.type == 0) {
+	int8_t to_position = xy_to_position(x, y);
+	if (!speculative_check(game_state, origin, to_position, self.type)) {
+	  *moves++ = {type, to_position};
+	}
+      } else {
+	break;
+      }
+    }
+    advance += 1;
+    type = move_type::pawn_double_advance;
+  } while (self.movement == movement_state::not_moved && advance <= 2);
+
+  int8_t diagonal = 1;
+  for (int i = 0; i < 2; i++) {
+    int8_t x = ox + diagonal;
+    int8_t y = oy + direction;
+
+    if (xy_inside_board(x, y)) {
+      piece& other = board.board[xy_to_position(x, y)];
+      bool different_sides = ((self.type ^ other.type) < 0);
+      if (other.type != 0 && different_sides) {
+	int8_t to_position = xy_to_position(x, y);
+	if (!speculative_check(game_state, origin, to_position, self.type))
+	  *moves++ = {move_type::normal, to_position};
+      }
+      if (game_state.en_passant_target != -1 && xy_to_position(x, oy) == game_state.en_passant_target) {
+	// en_passant_target is always the opposite side
+	int8_t to_position = xy_to_position(x, y);
+	if (!speculative_check(game_state, origin, to_position, self.type))
+	  *moves++ = {move_type::pawn_en_passant_capture, to_position};
+      }
+    }
+    diagonal = -diagonal;
+  }
+
+  return moves;
+}
+
+move_t * moves_knight(game_state& game_state, int8_t origin, move_t * moves)
+{
+  board_state& board = game_state.board;
+  piece& self = board.board[origin];
+  xy delta[8] = {
+    { 2, -1}, // up, left
+    { 2,  1}, // up, right
+    {-2, -1}, // down, left
+    {-2,  1}, // down, right
+    { 1, -2}, // left, up
+    { 1,  2}, // right, up
+    {-1, -2}, // left, down
+    {-1,  2}, // right, down
+  };
+  auto [ox, oy] = position_to_xy(origin);
+  for (int i = 0; i < 8; i++) {
+    uint8_t x = ox + delta[i].x;
+    uint8_t y = oy + delta[i].y;
+    if (xy_inside_board(x, y)) {
+      piece& other = board.board[xy_to_position(x, y)];
+      bool different_sides = ((self.type ^ other.type) < 0);
+      if (other.type == 0 || different_sides) {
+	int8_t to_position = xy_to_position(x, y);
+	if (!speculative_check(game_state, origin, to_position, self.type))
+	  *moves++ = {move_type::normal, to_position};
+      }
+    }
+  }
+  return moves;
+}
+
+move_t * moves_bishop(game_state& game_state, int8_t origin, move_t * moves)
+{
+  // up-left
+  moves = moves_line<8>(game_state, origin, moves,  1,  1);
+  // up-right
+  moves = moves_line<8>(game_state, origin, moves, -1,  1);
+  // down-left
+  moves = moves_line<8>(game_state, origin, moves,  1, -1);
+  // down-right
+  moves = moves_line<8>(game_state, origin, moves, -1, -1);
+
+  return moves;
+}
+
+move_t * moves_rook(game_state& game_state, int8_t origin, move_t * moves)
+{
+  // up
+  moves = moves_line<8>(game_state, origin, moves,  0,  1);
+  // down
+  moves = moves_line<8>(game_state, origin, moves,  0, -1);
+  // left
+  moves = moves_line<8>(game_state, origin, moves,  1,  0);
+  // right
+  moves = moves_line<8>(game_state, origin, moves, -1,  0);
+
+  return moves;
+}
+
+move_t * moves_queen(game_state& game_state, int8_t origin, move_t * moves)
+{
+  moves = moves_bishop(game_state, origin, moves);
+  moves = moves_rook(game_state, origin, moves);
+
+  return moves;
+}
+
+move_t * moves_king(game_state& game_state, int8_t origin, move_t * moves)
+{
+  // up-left
+  moves = moves_line<1>(game_state, origin, moves,  1,  1);
+  // up-right
+  moves = moves_line<1>(game_state, origin, moves, -1,  1);
+  // down-left
+  moves = moves_line<1>(game_state, origin, moves,  1, -1);
+  // down-right
+  moves = moves_line<1>(game_state, origin, moves, -1, -1);
+  // up
+  moves = moves_line<1>(game_state, origin, moves,  0,  1);
+  // down
+  moves = moves_line<1>(game_state, origin, moves,  0, -1);
+  // left
+  moves = moves_line<1>(game_state, origin, moves,  1,  0);
+  // right
+  moves = moves_line<1>(game_state, origin, moves, -1,  0);
+
+  // castle
+  board_state& board = game_state.board;
+  piece& self = board.board[origin];
+  if (self.movement == movement_state::not_moved && !speculative_check(game_state, origin, origin, self.type)) {
+    int direction = 1;
+    int distance = 2;
+    move_type type = move_type::castle_short;
+    auto [ox, oy] = position_to_xy(origin);
+    do {
+      int8_t rook_position = xy_to_position(direction == 1 ? 7 : 0, oy);
+      piece& rook = board.board[rook_position];
+      if (__builtin_abs(rook.type) == piece_type::rook && rook.movement == movement_state::not_moved) {
+	move_t * castle_moves = moves_line<8>(game_state, origin, moves, direction, 0);
+	if (castle_moves - moves == distance) {
+	  int8_t to_position = xy_to_position(ox + (direction * 2), oy);
+	  *moves++ = {type, to_position};
+	}
+      }
+      distance += 1;
+      direction = -direction;
+      type = move_type::castle_long;
+    } while (direction == -1);
+  }
+
+  return moves;
+}
+
+int moves_position(game_state& game_state, int8_t origin, move_t * moves)
+{
+  board_state& board = game_state.board;
+  piece& self = board.board[origin];
+  switch (__builtin_abs(self.type)) {
+  case piece_type::pawn:   return moves_pawn(game_state, origin, moves) - moves;
+  case piece_type::knight: return moves_knight(game_state, origin, moves) - moves;
+  case piece_type::bishop: return moves_bishop(game_state, origin, moves) - moves;
+  case piece_type::rook:   return moves_rook(game_state, origin, moves) - moves;
+  case piece_type::queen:  return moves_queen(game_state, origin, moves) - moves;
+  case piece_type::king:   return moves_king(game_state, origin, moves) - moves;
+  default:                 return 0;
+  }
+}
+
+static void board_init(game_state& game_state)
+{
+  using namespace piece_type;
+
+  constexpr int8_t types[8][8] = {
+    { rook  ,  knight,  bishop,  queen ,  king  ,  bishop,  knight,  rook  }, // white
+    { pawn  ,  pawn  ,  pawn  ,  pawn  ,  pawn  ,  pawn  ,  pawn  ,  pawn  }, // white
+    { empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty },
+    { empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty },
+    { empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty },
+    { empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty ,  empty },
+    {-pawn  , -pawn  , -pawn  , -pawn  , -pawn  , -pawn  , -pawn  , -pawn  }, // black
+    {-rook  , -knight, -bishop, -queen , -king  , -bishop, -knight, -rook  }, // black
+  };
+
+  game_state.piece_list.length = 0;
+  for (int y = 0; y < 8; y++) {
+    for (int x = 0; x < 8; x++) {
+      int8_t type = types[y][x];
+      int8_t position = xy_to_position(x, y);
+      piece& p = game_state.board.board[position];
+      p.type = type;
+      p.movement = movement_state::not_moved;
+      p.piece_list_offset = game_state.piece_list.length;
+      switch (__builtin_abs(type)) {
+      case empty: break;
+      default:
+	game_state.piece_list.piece[game_state.piece_list.length++] = &p;
+	break;
+      }
+    }
+  }
+}
+
+void game_init(game_state& game_state)
+{
+  game_state.turn = -1; // white
+  game_state.en_passant_target = -1;
+  game_state.halfmove_number = 0;
+  game_state.fullmove_number = 0;
+  game_state.interaction.selected_position = -1;
+  board_init(game_state);
+}
+
+int position_in_moves(moves_list& moves, int8_t position)
+{
+  for (int i = 0; i < moves.length; i++) {
+    int8_t move_position = moves.moves[i].to_position;
+    if (move_position == position) {
+      return i;
+    }
+  }
+  return -1;
+}
+
+void piece_list_delete(piece_list& list, int8_t offset)
+{
+  for (int i = offset + 1; i < list.length; i++) {
+    list.piece[i]->piece_list_offset = i - 1;
+    list.piece[i - 1] = list.piece[i];
+  }
+  list.length -= 1;
+}
+
+static int _speculative_check_depth = 0;
+
+bool speculative_check(game_state& game_state, int8_t from_position, int8_t to_position, int8_t side)
+{
+  if (_speculative_check_depth > 0)
+    return false;
+  _speculative_check_depth++;
+
+  piece& origin = game_state.board.board[from_position];
+  piece& destination = game_state.board.board[to_position];
+  const int8_t origin_type = origin.type;
+  const int8_t destination_type = destination.type;
+
+  origin.type = piece_type::empty;
+  destination.type = origin_type;
+
+  bool check = false;
+
+  for (int i = 0; i < game_state.piece_list.length; i++) {
+    if (i == origin.piece_list_offset) {
+      continue;
+    }
+    piece * test_piece = game_state.piece_list.piece[i];
+    if (turn_same_side(side, test_piece->type)) {
+      continue;
+    }
+    int8_t position = piece_list_to_position(game_state.board, test_piece);
+    moves_list ml;
+    ml.length = moves_position(game_state, position, ml.moves);
+    for (int j = 0; j < ml.length; j++) {
+      int8_t move_position = ml.moves[j].to_position;
+      piece& move_piece = game_state.board.board[move_position];
+      if (__builtin_abs(move_piece.type) == piece_type::king) {
+	serial::string("check\n");
+	check = true;
+	goto exit;
+      }
+    }
+  }
+
+ exit:
+  origin.type = origin_type;
+  destination.type = destination_type;
+
+  _speculative_check_depth--;
+
+  return check;
+}
+
+void do_move(game_state& game_state, int8_t from_position, move_t& move)
+{
+  piece& origin = game_state.board.board[from_position];
+  piece& destination = game_state.board.board[move.to_position];
+
+  if (destination.type != 0) { // capture
+    piece_list_delete(game_state.piece_list, destination.piece_list_offset);
+  }
+
+  int8_t en_passant_target = game_state.en_passant_target;
+  game_state.en_passant_target = -1;
+
+  switch (move.type) {
+  case move_type::pawn_double_advance:
+    serial::string("pawn double advance\n");
+    game_state.en_passant_target = move.to_position;
+    break;
+  case move_type::castle_short:
+    serial::string("move castle short\n");
+    {
+      auto [ox, oy] = position_to_xy(move.to_position);
+      int8_t rook_from = xy_to_position(7, oy);
+      move_t rook_move = {move_type::normal, xy_to_position(5, oy)};
+      do_move(game_state, rook_from, rook_move);
+    }
+    break;
+  case move_type::castle_long:
+    serial::string("move castle long\n");
+    {
+      auto [ox, oy] = position_to_xy(move.to_position);
+      int8_t rook_from = xy_to_position(0, oy);
+      move_t rook_move = {move_type::normal, xy_to_position(3, oy)};
+      do_move(game_state, rook_from, rook_move);
+    }
+    break;
+  case move_type::pawn_en_passant_capture:
+    {
+      serial::string("move en passant capture\n");
+      piece& en_passant_piece = game_state.board.board[en_passant_target];
+      serial::integer<uint8_t>(en_passant_target);
+      serial::integer<uint8_t>(en_passant_piece.type);
+      en_passant_piece.type = piece_type::empty;
+      piece_list_delete(game_state.piece_list, en_passant_piece.piece_list_offset);
+    }
+    break;
+  default: break;
+  }
+
+  destination.type = origin.type;
+  destination.movement = true;
+  destination.piece_list_offset = origin.piece_list_offset;
+  origin.type = piece_type::empty;
+  game_state.piece_list.piece[origin.piece_list_offset] = &destination;
+
+  game_state.turn = -game_state.turn;
+}
+
+void select_position(game_state& game_state, int8_t x, int8_t y)
+{
+  int8_t position = xy_to_position(x, y);
+
+  if (turn_same_side(game_state.turn, game_state.board.board[position].type)) {
+    if (game_state.interaction.selected_position != position) {
+      game_state.interaction.selected_position = position;
+      game_state.interaction.moves.length = moves_position(game_state,
+							   position,
+							   game_state.interaction.moves.moves);
+      return;
+    }
+  } else { // not same side or empty
+    if (game_state.interaction.selected_position != -1) {
+      int moves_ix = position_in_moves(game_state.interaction.moves, position);
+      if (moves_ix >= 0) {
+	do_move(game_state,
+		game_state.interaction.selected_position, // from
+		game_state.interaction.moves.moves[moves_ix]); // to
+	// fall through to deselect
+      }
+    }
+  }
+
+  game_state.interaction.selected_position = -1;
+  game_state.interaction.moves.length = 0;
+}
+
+}
diff --git a/chess/chess.hpp b/chess/chess.hpp
new file mode 100644
index 0000000..eecc96e
--- /dev/null
+++ b/chess/chess.hpp
@@ -0,0 +1,82 @@
+#pragma once
+
+#include <cstdint>
+
+namespace chess {
+
+namespace piece_type {
+constexpr int8_t empty = 0;
+constexpr int8_t pawn = 1;
+constexpr int8_t knight = 2;
+constexpr int8_t bishop = 3;
+constexpr int8_t rook = 4;
+constexpr int8_t queen = 5;
+constexpr int8_t king = 6;
+};
+
+namespace movement_state {
+constexpr int8_t not_moved = 0;
+constexpr int8_t moved = 1;
+}
+
+struct xy {
+  int8_t x;
+  int8_t y;
+};
+
+struct piece {
+  int8_t type;      // piece_type
+  int8_t movement;  // movement_state
+  int8_t piece_list_offset;
+};
+
+struct piece_list {
+  struct piece * piece[8 * 8];
+  int32_t length;
+};
+
+struct board_state {
+  struct piece board[8 * 16];
+};
+
+enum struct move_type : int8_t {
+  normal,
+  castle_short,
+  castle_long,
+  pawn_double_advance,
+  pawn_en_passant_capture,
+};
+
+struct move_t {
+  enum move_type type;
+  int8_t to_position;
+};
+
+struct moves_list {
+  move_t moves[27];
+  int8_t length;
+};
+
+struct interaction_state {
+  int8_t selected_position;
+  struct moves_list moves;
+};
+
+struct game_state {
+  struct board_state board;
+  struct piece_list piece_list;
+  struct interaction_state interaction;
+  int8_t turn;
+  int8_t en_passant_target; // index into board_state.board
+  uint16_t halfmove_number;
+  uint16_t fullmove_number;
+};
+
+xy position_to_xy(int8_t position);
+int8_t xy_to_position(int8_t x, int8_t y);
+void game_init(game_state& game_state);
+void select_position(game_state& game_state, int8_t x, int8_t y);
+int8_t piece_list_to_position(const chess::board_state& board_state,
+			      chess::piece * piece);
+
+}
diff --git a/chess/chess.mk b/chess/chess.mk
new file mode 100644
index 0000000..052f496
--- /dev/null
+++ b/chess/chess.mk
@@ -0,0 +1,33 @@
+CHESS_OBJ = \
+	chess/main.o \
+	chess/render.o \
+	chess/chess.o \
+	chess/input.o \
+	holly/video_output.o \
+	holly/core.o \
+	holly/region_array.o \
+	holly/background.o \
+	holly/ta_fifo_polygon_converter.o \
+	maple/maple.o \
+	sh7091/serial.o \
+	$(LIBGCC)
+
+CHESS_GEOMETRY = \
+	chess/bishop.hpp \
+	chess/king.hpp \
+	chess/knight.hpp \
+	chess/pawn.hpp \
+	chess/queen.hpp \
+	chess/rook.hpp \
+	chess/square.hpp \
+	chess/circle.hpp \
+	chess/cursor.hpp
+
+chess/render.o: chess/render.cpp $(CHESS_GEOMETRY)
+
+chess/chess.elf: LDSCRIPT = $(LIB)/main.lds
+chess/chess.elf: $(START_OBJ) $(CHESS_OBJ)
+
+chess/%.hpp: chess/%.obj tools/obj_to_cpp.py
+	PYTHONPATH=regs/gen python tools/obj_to_cpp.py $< > $@.tmp
+	mv $@.tmp $@
diff --git a/chess/circle.blend b/chess/circle.blend
new file mode 100644
index 0000000..852985b
Binary files /dev/null and b/chess/circle.blend differ
diff --git a/chess/circle.hpp b/chess/circle.hpp
new file mode 100644
index 0000000..09e159f
--- /dev/null
+++ b/chess/circle.hpp
@@ -0,0 +1,49 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace circle {
+  constexpr vec3 vertices[] = {
+    {  0.000000f,  0.000000f,  0.000000f },
+    {  0.000000f, -1.000000f,  0.000000f },
+    { -0.361242f, -0.932472f,  0.000000f },
+    { -0.673696f, -0.739009f,  0.000000f },
+    { -0.895163f, -0.445738f,  0.000000f },
+    { -0.995734f, -0.092268f,  0.000000f },
+    { -0.961826f,  0.273663f, -0.000000f },
+    { -0.798017f,  0.602635f, -0.000000f },
+    { -0.526432f,  0.850217f, -0.000000f },
+    { -0.183750f,  0.982973f, -0.000000f },
+    {  0.183750f,  0.982973f, -0.000000f },
+    {  0.526432f,  0.850217f, -0.000000f },
+    {  0.798017f,  0.602635f, -0.000000f },
+    {  0.961826f,  0.273663f, -0.000000f },
+    {  0.995734f, -0.092268f,  0.000000f },
+    {  0.895163f, -0.445738f,  0.000000f },
+    {  0.673696f, -0.739009f,  0.000000f },
+    {  0.361242f, -0.932472f,  0.000000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{ 0}, { 1}, { 2}},
+    {{ 0}, { 2}, { 3}},
+    {{ 0}, { 3}, { 4}},
+    {{ 0}, { 4}, { 5}},
+    {{ 0}, { 5}, { 6}},
+    {{ 0}, { 6}, { 7}},
+    {{ 0}, { 7}, { 8}},
+    {{ 0}, { 8}, { 9}},
+    {{ 0}, { 9}, {10}},
+    {{ 0}, {10}, {11}},
+    {{ 0}, {11}, {12}},
+    {{ 0}, {12}, {13}},
+    {{ 0}, {13}, {14}},
+    {{ 0}, {14}, {15}},
+    {{ 0}, {15}, {16}},
+    {{ 0}, {16}, {17}},
+    {{ 0}, {17}, { 1}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/circle.obj b/chess/circle.obj
new file mode 100644
index 0000000..2372ee8
--- /dev/null
+++ b/chess/circle.obj
@@ -0,0 +1,39 @@
+# Blender 3.3.6
+# www.blender.org
+o Circle
+v 0.000000 0.000000 0.000000
+v 0.000000 -1.000000 0.000000
+v -0.361242 -0.932472 0.000000
+v -0.673696 -0.739009 0.000000
+v -0.895163 -0.445738 0.000000
+v -0.995734 -0.092268 0.000000
+v -0.961826 0.273663 -0.000000
+v -0.798017 0.602635 -0.000000
+v -0.526432 0.850217 -0.000000
+v -0.183750 0.982973 -0.000000
+v 0.183750 0.982973 -0.000000
+v 0.526432 0.850217 -0.000000
+v 0.798017 0.602635 -0.000000
+v 0.961826 0.273663 -0.000000
+v 0.995734 -0.092268 0.000000
+v 0.895163 -0.445738 0.000000
+v 0.673696 -0.739009 0.000000
+v 0.361242 -0.932472 0.000000
+s 0
+f 1 2 3
+f 1 3 4
+f 1 4 5
+f 1 5 6
+f 1 6 7
+f 1 7 8
+f 1 8 9
+f 1 9 10
+f 1 10 11
+f 1 11 12
+f 1 12 13
+f 1 13 14
+f 1 14 15
+f 1 15 16
+f 1 16 17
+f 1 17 18
+f 1 18 2
diff --git a/chess/cursor.blend b/chess/cursor.blend
new file mode 100644
index 0000000..ceeace3
Binary files /dev/null and b/chess/cursor.blend differ
diff --git a/chess/cursor.hpp b/chess/cursor.hpp
new file mode 100644
index 0000000..78311ac
--- /dev/null
+++ b/chess/cursor.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace cursor {
+  constexpr vec3 vertices[] = {
+    {  0.407995f, -0.805648f,  2.000000f },
+    {  0.000000f,  0.000000f,  2.000000f },
+    {  0.550770f, -0.527772f,  2.000000f },
+    {  0.302290f, -0.556623f,  2.000000f },
+    {  0.297535f, -0.852536f,  2.000000f },
+    {  0.000000f, -0.762211f,  2.000000f },
+    {  0.191836f, -0.603526f,  2.000000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{1}, {6}, {0}},
+    {{3}, {2}, {1}},
+    {{1}, {5}, {6}},
+    {{6}, {4}, {0}},
+    {{0}, {3}, {1}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/cursor.obj b/chess/cursor.obj
new file mode 100644
index 0000000..870e10a
--- /dev/null
+++ b/chess/cursor.obj
@@ -0,0 +1,16 @@
+# Blender 3.3.6
+# www.blender.org
+o Cursor
+v 0.407995 -0.805648 2.000000
+v 0.000000 0.000000 2.000000
+v 0.550770 -0.527772 2.000000
+v 0.302290 -0.556623 2.000000
+v 0.297535 -0.852536 2.000000
+v 0.000000 -0.762211 2.000000
+v 0.191836 -0.603526 2.000000
+s 0
+f 2 7 1
+f 4 3 2
+f 2 6 7
+f 7 5 1
+f 1 4 2
diff --git a/chess/input.cpp b/chess/input.cpp
new file mode 100644
index 0000000..ca4bc22
--- /dev/null
+++ b/chess/input.cpp
@@ -0,0 +1,108 @@
+#include <bit>
+
+#include "maple/maple.hpp"
+#include "maple/maple_port.hpp"
+#include "maple/maple_bus_bits.hpp"
+#include "maple/maple_bus_commands.hpp"
+#include "maple/maple_bus_ft0.hpp"
+#include "maple/maple_bus_ft9.hpp"
+#include "maple/maple_host_command_writer.hpp"
+
+#include "sh7091/serial.hpp"
+
+#include "input.hpp"
+
+namespace input {
+
+struct input_state state;
+
+void do_get_condition_controller(maple::host_command_writer& writer,
+				 const uint32_t port)
+{
+  using command_type = maple::get_condition;
+  using response_type = maple::data_transfer<ft0::data_transfer::data_format>;
+
+  uint32_t host_port_select = host_instruction_port_select(port);
+  uint32_t destination_ap = ap_port_select(port) | ap::de::device;
+
+  auto [host_command, host_response]
+    = writer.append_command<command_type, response_type>(host_port_select,
+							 destination_ap,
+							 false); // end_flag
+
+  host_command->bus_data.data_fields.function_type = std::byteswap(function_type::controller);
+
+  state.port[port].host_response_data_transfer_ft0 = host_response;
+}
+
+void do_get_condition_pointing(maple::host_command_writer& writer,
+			       const uint32_t port)
+{
+  using command_type = maple::get_condition;
+  using response_type = maple::data_transfer<ft9::data_transfer::data_format>;
+
+  uint32_t host_port_select = host_instruction_port_select(port);
+  uint32_t destination_ap = ap_port_select(port) | ap::de::device;
+
+  auto [host_command, host_response]
+    = writer.append_command<command_type, response_type>(host_port_select,
+							 destination_ap,
+							 false); // end_flag
+
+  host_command->bus_data.data_fields.function_type = std::byteswap(function_type::pointing);
+
+  state.port[port].host_response_data_transfer_ft9 = host_response;
+}
+
+maple::host_response<maple::device_status::data_fields> * do_device_request(maple::host_command_writer& writer)
+{
+  using command_type = maple::device_request;
+  using response_type = maple::device_status;
+
+  auto [host_command, host_response]
+    = writer.append_command_all_ports<command_type, response_type>();
+
+  return host_response;
+}
+
+void state_update(uint32_t * send_buf, uint32_t * recv_buf)
+{
+  maple::host_command_writer writer(send_buf, recv_buf);
+
+  for (uint8_t port = 0; port < 4; port++) {
+    state.port[port].function_type = state.port[port].next_function_type;
+
+    if (state.port[port].function_type & function_type::controller) {
+      do_get_condition_controller(writer, port);
+    }
+
+    if (state.port[port].function_type & function_type::pointing) {
+      do_get_condition_pointing(writer, port);
+    }
+  }
+  auto host_response_device_status = do_device_request(writer);
+
+  maple::dma_start(writer.send_buf, writer.send_offset,
+                   writer.recv_buf, writer.recv_offset);
+
+  for (uint8_t port = 0; port < 4; port++) {
+    auto& bus_data = host_response_device_status[port].bus_data;
+    auto& data_fields = bus_data.data_fields;
+    if (bus_data.command_code != maple::device_status::command_code) {
+      state.port[port].function_type = 0;
+      state.port[port].next_function_type = 0;
+      continue;
+    } else {
+      state.port[port].next_function_type = std::byteswap(data_fields.device_id.ft);
+    }
+  }
+}
+
+void state_init()
+{
+  for (uint8_t port = 0; port < 4; port++) {
+    state.port[port].function_type = 0;
+  }
+}
+
+}
diff --git a/chess/input.hpp b/chess/input.hpp
new file mode 100644
index 0000000..19bf60d
--- /dev/null
+++ b/chess/input.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "maple/maple.hpp"
+#include "maple/maple_bus_commands.hpp"
+#include "maple/maple_bus_ft0.hpp"
+#include "maple/maple_bus_ft9.hpp"
+
+namespace input {
+
+struct port_state {
+  uint32_t function_type;
+  uint32_t next_function_type;
+  maple::host_response<maple::data_transfer<ft0::data_transfer::data_format>::data_fields> * host_response_data_transfer_ft0;
+  maple::host_response<maple::data_transfer<ft9::data_transfer::data_format>::data_fields> * host_response_data_transfer_ft9;
+};
+
+struct input_state {
+  port_state port[4];
+};
+
+extern input_state state;
+
+void state_update(uint32_t * send_buf, uint32_t * recv_buf);
+void state_init();
+
+}
diff --git a/chess/king.blend b/chess/king.blend
new file mode 100644
index 0000000..175901c
Binary files /dev/null and b/chess/king.blend differ
diff --git a/chess/king.hpp b/chess/king.hpp
new file mode 100644
index 0000000..3058dab
--- /dev/null
+++ b/chess/king.hpp
@@ -0,0 +1,250 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace king {
+  constexpr vec3 vertices[] = {
+    {  0.587722f, -0.812159f, -0.500000f },
+    {  0.508186f, -0.497465f, -0.500000f },
+    {  0.569728f, -0.561184f, -0.500000f },
+    {  0.590376f, -0.644625f, -0.500000f },
+    {  0.451429f, -0.468419f, -0.500000f },
+    {  0.713971f, -0.169361f, -0.500000f },
+    {  0.769329f, -0.073675f, -0.500000f },
+    {  0.787068f,  0.014243f, -0.500000f },
+    {  0.781478f,  0.126337f, -0.500000f },
+    {  0.743187f,  0.238086f, -0.500000f },
+    {  0.681645f,  0.323805f, -0.500000f },
+    {  0.604056f,  0.381043f, -0.500000f },
+    {  0.502300f,  0.423017f, -0.500000f },
+    {  0.406904f,  0.435736f, -0.500000f },
+    {  0.274621f,  0.424289f, -0.500000f },
+    {  0.163962f,  0.386130f, -0.500000f },
+    {  0.143610f,  0.464991f, -0.500000f },
+    {  0.263174f,  0.464991f, -0.500000f },
+    {  0.261902f,  0.705390f, -0.500000f },
+    {  0.134707f,  0.706662f, -0.500000f },
+    {  0.133435f,  0.837673f, -0.500000f },
+    { -0.587722f, -0.812159f, -0.500000f },
+    { -0.508186f, -0.497465f, -0.500000f },
+    { -0.569728f, -0.561184f, -0.500000f },
+    { -0.590376f, -0.644625f, -0.500000f },
+    { -0.451429f, -0.468419f, -0.500000f },
+    { -0.713971f, -0.169361f, -0.500000f },
+    { -0.769329f, -0.073675f, -0.500000f },
+    { -0.787068f,  0.014243f, -0.500000f },
+    { -0.781478f,  0.126337f, -0.500000f },
+    { -0.743187f,  0.238086f, -0.500000f },
+    { -0.681645f,  0.323805f, -0.500000f },
+    { -0.604056f,  0.381043f, -0.500000f },
+    { -0.502300f,  0.423017f, -0.500000f },
+    { -0.406904f,  0.435736f, -0.500000f },
+    { -0.274621f,  0.424289f, -0.500000f },
+    { -0.163962f,  0.386130f, -0.500000f },
+    { -0.143610f,  0.464991f, -0.500000f },
+    { -0.263174f,  0.464991f, -0.500000f },
+    { -0.261902f,  0.705390f, -0.500000f },
+    { -0.134707f,  0.706662f, -0.500000f },
+    { -0.133435f,  0.837673f, -0.500000f },
+    { -0.232004f, -0.196898f, -0.500000f },
+    { -0.186214f, -0.196898f, -0.500000f },
+    {  0.186214f, -0.196898f, -0.500000f },
+    {  0.232004f, -0.196898f, -0.500000f },
+    {  0.187740f,  0.064106f, -0.500000f },
+    {  0.361743f,  0.103791f, -0.500000f },
+    {  0.286952f,  0.109897f, -0.500000f },
+    {  0.416691f,  0.025948f, -0.500000f },
+    {  0.398375f, -0.019843f, -0.500000f },
+    {  0.392270f,  0.074791f, -0.500000f },
+    { -0.416691f,  0.025948f, -0.500000f },
+    { -0.398375f, -0.019843f, -0.500000f },
+    { -0.392270f,  0.074791f, -0.500000f },
+    { -0.286952f,  0.109897f, -0.500000f },
+    { -0.361743f,  0.103791f, -0.500000f },
+    { -0.187740f,  0.064106f, -0.500000f },
+    { -0.625504f,  0.268384f, -1.500000f },
+    { -0.565495f,  0.312652f, -1.500000f },
+    {  0.461141f, -0.560928f, -1.500000f },
+    {  0.499116f, -0.600247f, -1.500000f },
+    {  0.511019f, -0.734231f, -1.500000f },
+    {  0.512298f, -0.653515f, -1.500000f },
+    {  0.326852f, -0.492204f, -1.500000f },
+    {  0.650355f, -0.123707f, -1.500000f },
+    {  0.695471f, -0.045723f, -1.500000f },
+    {  0.708752f,  0.020099f, -1.500000f },
+    {  0.704195f,  0.111476f, -1.500000f },
+    {  0.673189f,  0.201964f, -1.500000f },
+    {  0.625504f,  0.268384f, -1.500000f },
+    {  0.565495f,  0.312652f, -1.500000f },
+    {  0.481954f,  0.347113f, -1.500000f },
+    {  0.405092f,  0.357361f, -1.500000f },
+    {  0.290927f,  0.347481f, -1.500000f },
+    {  0.109592f,  0.284952f, -1.500000f },
+    {  0.043020f,  0.542919f, -1.500000f },
+    {  0.184833f,  0.542919f, -1.500000f },
+    {  0.184381f,  0.628234f, -1.500000f },
+    {  0.057525f,  0.629502f, -1.500000f },
+    {  0.056260f,  0.759745f, -1.500000f },
+    { -0.511019f, -0.734231f, -1.500000f },
+    { -0.461141f, -0.560928f, -1.500000f },
+    { -0.499116f, -0.600247f, -1.500000f },
+    { -0.512298f, -0.653515f, -1.500000f },
+    { -0.326852f, -0.492204f, -1.500000f },
+    { -0.650355f, -0.123707f, -1.500000f },
+    { -0.695471f, -0.045723f, -1.500000f },
+    { -0.708752f,  0.020099f, -1.500000f },
+    { -0.704195f,  0.111476f, -1.500000f },
+    { -0.673189f,  0.201964f, -1.500000f },
+    { -0.481954f,  0.347113f, -1.500000f },
+    { -0.405092f,  0.357361f, -1.500000f },
+    { -0.290927f,  0.347481f, -1.500000f },
+    { -0.109592f,  0.284952f, -1.500000f },
+    { -0.043020f,  0.542919f, -1.500000f },
+    { -0.184833f,  0.542919f, -1.500000f },
+    { -0.184381f,  0.628234f, -1.500000f },
+    { -0.057525f,  0.629502f, -1.500000f },
+    { -0.056260f,  0.759745f, -1.500000f },
+    { -0.265712f, -0.274826f, -1.500000f },
+    { -0.107829f, -0.274826f, -1.500000f },
+    {  0.107829f, -0.274826f, -1.500000f },
+    {  0.265712f, -0.274826f, -1.500000f },
+    {  0.110104f,  0.114101f, -1.500000f },
+    {  0.395484f,  0.179223f, -1.500000f },
+    {  0.272886f,  0.189231f, -1.500000f },
+    {  0.502042f,  0.029498f, -1.500000f },
+    {  0.465256f, -0.062466f, -1.500000f },
+    {  0.455855f,  0.121871f, -1.500000f },
+    { -0.465256f, -0.062466f, -1.500000f },
+    { -0.502042f,  0.029498f, -1.500000f },
+    { -0.455855f,  0.121871f, -1.500000f },
+    { -0.272886f,  0.189231f, -1.500000f },
+    { -0.395484f,  0.179223f, -1.500000f },
+    { -0.110104f,  0.114101f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{ 71}, { 75}, {105}},
+    {{ 92}, {114}, { 94}},
+    {{ 76}, { 80}, { 95}},
+    {{  4}, { 45}, { 42}},
+    {{ 33}, { 55}, { 36}},
+    {{ 13}, { 15}, { 48}},
+    {{ 16}, { 40}, { 37}},
+    {{109}, {107}, { 67}},
+    {{ 67}, { 68}, { 69}},
+    {{ 69}, { 70}, { 71}},
+    {{ 71}, { 72}, { 73}},
+    {{ 73}, { 74}, { 75}},
+    {{ 75}, {106}, {105}},
+    {{105}, {109}, { 67}},
+    {{ 67}, { 69}, { 71}},
+    {{ 71}, { 73}, { 75}},
+    {{105}, { 67}, { 71}},
+    {{ 94}, { 93}, { 92}},
+    {{ 92}, { 91}, {114}},
+    {{114}, {113}, { 94}},
+    {{ 85}, { 82}, { 83}},
+    {{ 83}, { 84}, { 81}},
+    {{ 81}, { 62}, { 63}},
+    {{ 63}, { 61}, { 60}},
+    {{ 64}, { 65}, { 66}},
+    {{ 63}, { 60}, { 64}},
+    {{ 83}, { 81}, { 63}},
+    {{ 87}, { 86}, { 85}},
+    {{ 85}, { 83}, { 63}},
+    {{ 64}, { 66}, { 67}},
+    {{ 85}, { 63}, { 64}},
+    {{ 88}, { 87}, { 85}},
+    {{ 90}, { 89}, { 88}},
+    {{ 59}, { 58}, { 90}},
+    {{114}, { 91}, { 59}},
+    {{112}, {114}, { 59}},
+    {{ 59}, { 90}, { 88}},
+    {{ 64}, { 67}, {107}},
+    {{ 64}, {107}, {108}},
+    {{112}, { 59}, { 88}},
+    {{111}, {112}, { 88}},
+    {{ 64}, {108}, {103}},
+    {{ 64}, {103}, {102}},
+    {{111}, { 88}, { 85}},
+    {{110}, {111}, { 85}},
+    {{ 85}, { 64}, {102}},
+    {{104}, {106}, { 75}},
+    {{100}, {110}, { 85}},
+    {{101}, {100}, { 85}},
+    {{102}, {104}, { 75}},
+    {{ 76}, { 77}, { 78}},
+    {{102}, { 75}, { 76}},
+    {{101}, { 85}, {102}},
+    {{ 94}, {113}, {115}},
+    {{115}, {101}, {102}},
+    {{ 76}, { 78}, { 79}},
+    {{115}, {102}, { 76}},
+    {{ 95}, { 94}, {115}},
+    {{ 97}, { 96}, { 95}},
+    {{ 80}, { 99}, { 98}},
+    {{ 98}, { 97}, { 95}},
+    {{ 95}, {115}, { 76}},
+    {{ 76}, { 79}, { 80}},
+    {{ 80}, { 98}, { 95}},
+    {{ 32}, { 31}, { 30}},
+    {{ 30}, { 29}, { 28}},
+    {{ 28}, { 27}, { 26}},
+    {{ 25}, { 22}, { 23}},
+    {{ 28}, { 26}, { 25}},
+    {{ 32}, { 30}, { 28}},
+    {{ 56}, { 33}, { 32}},
+    {{ 54}, { 56}, { 32}},
+    {{ 32}, { 28}, { 25}},
+    {{ 25}, { 23}, { 24}},
+    {{ 24}, { 21}, {  0}},
+    {{  0}, {  3}, {  2}},
+    {{  2}, {  1}, {  4}},
+    {{  4}, {  5}, {  6}},
+    {{  6}, {  7}, {  8}},
+    {{  8}, {  9}, { 10}},
+    {{ 10}, { 11}, { 12}},
+    {{ 12}, { 47}, { 51}},
+    {{ 12}, { 51}, { 49}},
+    {{  8}, { 10}, { 12}},
+    {{  4}, {  6}, {  8}},
+    {{  0}, {  2}, {  4}},
+    {{ 25}, { 24}, {  0}},
+    {{ 52}, { 54}, { 32}},
+    {{ 53}, { 52}, { 32}},
+    {{ 25}, {  0}, {  4}},
+    {{  4}, {  8}, { 12}},
+    {{  4}, { 12}, { 49}},
+    {{ 53}, { 32}, { 25}},
+    {{ 44}, { 43}, { 42}},
+    {{ 42}, { 53}, { 25}},
+    {{  4}, { 49}, { 50}},
+    {{ 45}, { 44}, { 42}},
+    {{  4}, { 50}, { 45}},
+    {{ 42}, { 25}, {  4}},
+    {{ 35}, { 34}, { 33}},
+    {{ 33}, { 56}, { 55}},
+    {{ 55}, { 57}, { 36}},
+    {{ 36}, { 35}, { 33}},
+    {{ 47}, { 12}, { 13}},
+    {{ 13}, { 14}, { 15}},
+    {{ 15}, { 46}, { 48}},
+    {{ 48}, { 47}, { 13}},
+    {{ 46}, { 15}, { 16}},
+    {{ 16}, { 17}, { 18}},
+    {{ 19}, { 20}, { 41}},
+    {{ 16}, { 18}, { 19}},
+    {{ 44}, { 46}, { 16}},
+    {{ 57}, { 43}, { 44}},
+    {{ 37}, { 36}, { 57}},
+    {{ 39}, { 38}, { 37}},
+    {{ 19}, { 41}, { 40}},
+    {{ 40}, { 39}, { 37}},
+    {{ 37}, { 57}, { 44}},
+    {{ 16}, { 19}, { 40}},
+    {{ 37}, { 44}, { 16}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/king.obj b/chess/king.obj
new file mode 100644
index 0000000..e8b9e92
--- /dev/null
+++ b/chess/king.obj
@@ -0,0 +1,240 @@
+# Blender 3.3.6
+# www.blender.org
+o King
+v 0.587722 -0.812159 -0.500000
+v 0.508186 -0.497465 -0.500000
+v 0.569728 -0.561184 -0.500000
+v 0.590376 -0.644625 -0.500000
+v 0.451429 -0.468419 -0.500000
+v 0.713971 -0.169361 -0.500000
+v 0.769329 -0.073675 -0.500000
+v 0.787068 0.014243 -0.500000
+v 0.781478 0.126337 -0.500000
+v 0.743187 0.238086 -0.500000
+v 0.681645 0.323805 -0.500000
+v 0.604056 0.381043 -0.500000
+v 0.502300 0.423017 -0.500000
+v 0.406904 0.435736 -0.500000
+v 0.274621 0.424289 -0.500000
+v 0.163962 0.386130 -0.500000
+v 0.143610 0.464991 -0.500000
+v 0.263174 0.464991 -0.500000
+v 0.261902 0.705390 -0.500000
+v 0.134707 0.706662 -0.500000
+v 0.133435 0.837673 -0.500000
+v -0.587722 -0.812159 -0.500000
+v -0.508186 -0.497465 -0.500000
+v -0.569728 -0.561184 -0.500000
+v -0.590376 -0.644625 -0.500000
+v -0.451429 -0.468419 -0.500000
+v -0.713971 -0.169361 -0.500000
+v -0.769329 -0.073675 -0.500000
+v -0.787068 0.014243 -0.500000
+v -0.781478 0.126337 -0.500000
+v -0.743187 0.238086 -0.500000
+v -0.681645 0.323805 -0.500000
+v -0.604056 0.381043 -0.500000
+v -0.502300 0.423017 -0.500000
+v -0.406904 0.435736 -0.500000
+v -0.274621 0.424289 -0.500000
+v -0.163962 0.386130 -0.500000
+v -0.143610 0.464991 -0.500000
+v -0.263174 0.464991 -0.500000
+v -0.261902 0.705390 -0.500000
+v -0.134707 0.706662 -0.500000
+v -0.133435 0.837673 -0.500000
+v -0.232004 -0.196898 -0.500000
+v -0.186214 -0.196898 -0.500000
+v 0.186214 -0.196898 -0.500000
+v 0.232004 -0.196898 -0.500000
+v 0.187740 0.064106 -0.500000
+v 0.361743 0.103791 -0.500000
+v 0.286952 0.109897 -0.500000
+v 0.416691 0.025948 -0.500000
+v 0.398375 -0.019843 -0.500000
+v 0.392270 0.074791 -0.500000
+v -0.416691 0.025948 -0.500000
+v -0.398375 -0.019843 -0.500000
+v -0.392270 0.074791 -0.500000
+v -0.286952 0.109897 -0.500000
+v -0.361743 0.103791 -0.500000
+v -0.187740 0.064106 -0.500000
+v -0.625504 0.268384 -1.500000
+v -0.565495 0.312652 -1.500000
+v 0.461141 -0.560928 -1.500000
+v 0.499116 -0.600247 -1.500000
+v 0.511019 -0.734231 -1.500000
+v 0.512298 -0.653515 -1.500000
+v 0.326852 -0.492204 -1.500000
+v 0.650355 -0.123707 -1.500000
+v 0.695471 -0.045723 -1.500000
+v 0.708752 0.020099 -1.500000
+v 0.704195 0.111476 -1.500000
+v 0.673189 0.201964 -1.500000
+v 0.625504 0.268384 -1.500000
+v 0.565495 0.312652 -1.500000
+v 0.481954 0.347113 -1.500000
+v 0.405092 0.357361 -1.500000
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+v -0.272886 0.189231 -1.500000
+v -0.395484 0.179223 -1.500000
+v -0.110104 0.114101 -1.500000
+s 0
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diff --git a/chess/knight.blend b/chess/knight.blend
new file mode 100644
index 0000000..5b34d27
Binary files /dev/null and b/chess/knight.blend differ
diff --git a/chess/knight.hpp b/chess/knight.hpp
new file mode 100644
index 0000000..2973a7c
--- /dev/null
+++ b/chess/knight.hpp
@@ -0,0 +1,162 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace knight {
+  constexpr vec3 vertices[] = {
+    {  0.659379f, -0.816994f, -0.500000f },
+    {  0.562711f, -0.484379f, -0.500000f },
+    {  0.619948f, -0.544161f, -0.500000f },
+    {  0.660651f, -0.653548f, -0.500000f },
+    {  0.514377f, -0.460212f, -0.500000f },
+    {  0.590694f, -0.167663f, -0.500000f },
+    {  0.590694f,  0.056200f, -0.500000f },
+    {  0.542359f,  0.227913f, -0.500000f },
+    {  0.452051f,  0.393266f, -0.500000f },
+    {  0.356655f,  0.496294f, -0.500000f },
+    {  0.214196f,  0.587875f, -0.500000f },
+    {  0.062834f,  0.643840f, -0.500000f },
+    { -0.031290f,  0.656560f, -0.500000f },
+    { -0.172476f,  0.799018f, -0.500000f },
+    { -0.250065f,  0.795203f, -0.500000f },
+    { -0.297128f,  0.739237f, -0.500000f },
+    { -0.317479f,  0.631121f, -0.500000f },
+    { -0.419235f,  0.531909f, -0.500000f },
+    { -0.477744f,  0.408530f, -0.500000f },
+    { -0.509543f,  0.313134f, -0.500000f },
+    { -0.706695f,  0.014225f, -0.500000f },
+    { -0.707967f, -0.079899f, -0.500000f },
+    { -0.659633f, -0.147312f, -0.500000f },
+    { -0.506999f, -0.207094f, -0.500000f },
+    { -0.396340f, -0.207094f, -0.500000f },
+    { -0.307303f, -0.084987f, -0.500000f },
+    { -0.204275f, -0.082443f, -0.500000f },
+    { -0.124142f, -0.039196f, -0.500000f },
+    { -0.032562f,  0.048568f, -0.500000f },
+    { -0.035106f, -0.015029f, -0.500000f },
+    { -0.077080f, -0.078627f, -0.500000f },
+    { -0.206819f, -0.181655f, -0.500000f },
+    { -0.295856f, -0.277051f, -0.500000f },
+    { -0.363269f, -0.378807f, -0.500000f },
+    { -0.386164f, -0.457668f, -0.500000f },
+    { -0.462481f, -0.495826f, -0.500000f },
+    { -0.510815f, -0.551792f, -0.500000f },
+    { -0.534982f, -0.626837f, -0.500000f },
+    { -0.534982f, -0.816994f, -0.500000f },
+    {  0.500944f, -0.156150f, -1.500000f },
+    {  0.409169f, -0.507952f, -1.500000f },
+    {  0.508650f, -0.557692f, -1.500000f },
+    {  0.542299f, -0.592837f, -1.500000f },
+    {  0.570775f, -0.669367f, -1.500000f },
+    {  0.570325f, -0.744827f, -1.500000f },
+    {  0.500944f,  0.043809f, -1.500000f },
+    {  0.458720f,  0.193813f, -1.500000f },
+    {  0.378625f,  0.340467f, -1.500000f },
+    {  0.298539f,  0.426959f, -1.500000f },
+    {  0.173894f,  0.507088f, -1.500000f },
+    {  0.040999f,  0.556225f, -1.500000f },
+    { -0.073553f,  0.571706f, -1.500000f },
+    { -0.209298f,  0.704796f, -1.500000f },
+    { -0.234523f,  0.586654f, -1.500000f },
+    { -0.345045f,  0.478895f, -1.500000f },
+    { -0.394320f,  0.374988f, -1.500000f },
+    { -0.428129f,  0.273563f, -1.500000f },
+    { -0.617309f, -0.013258f, -1.500000f },
+    { -0.617827f, -0.051594f, -1.500000f },
+    { -0.602171f, -0.073430f, -1.500000f },
+    { -0.490050f, -0.117344f, -1.500000f },
+    { -0.441973f, -0.117344f, -1.500000f },
+    { -0.353752f,  0.003644f, -1.500000f },
+    { -0.227982f,  0.006749f, -1.500000f },
+    { -0.177465f,  0.034012f, -1.500000f },
+    {  0.029378f,  0.195605f, -1.500000f },
+    {  0.053573f, -0.043600f, -1.500000f },
+    { -0.010058f, -0.140010f, -1.500000f },
+    { -0.145769f, -0.247781f, -1.500000f },
+    { -0.225155f, -0.332837f, -1.500000f },
+    { -0.280893f, -0.416969f, -1.500000f },
+    { -0.310917f, -0.520388f, -1.500000f },
+    { -0.406289f, -0.568074f, -1.500000f },
+    { -0.430974f, -0.596657f, -1.500000f },
+    { -0.445232f, -0.640932f, -1.500000f },
+    { -0.445232f, -0.744827f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{ 4}, {28}, {29}},
+    {{40}, {67}, {71}},
+    {{ 4}, { 5}, { 6}},
+    {{ 6}, { 7}, { 8}},
+    {{ 8}, { 9}, {10}},
+    {{10}, {11}, {12}},
+    {{12}, {13}, {14}},
+    {{14}, {15}, {16}},
+    {{16}, {17}, {18}},
+    {{19}, {20}, {21}},
+    {{16}, {18}, {19}},
+    {{12}, {14}, {16}},
+    {{ 8}, {10}, {12}},
+    {{ 4}, { 6}, { 8}},
+    {{ 2}, { 1}, { 4}},
+    {{ 0}, { 3}, { 2}},
+    {{37}, {38}, { 0}},
+    {{35}, {36}, {37}},
+    {{32}, {33}, {34}},
+    {{34}, {35}, {37}},
+    {{37}, { 0}, { 2}},
+    {{ 4}, { 8}, {12}},
+    {{37}, { 2}, { 4}},
+    {{31}, {32}, {34}},
+    {{34}, {37}, { 4}},
+    {{ 4}, {12}, {16}},
+    {{16}, {19}, {21}},
+    {{21}, {22}, {23}},
+    {{23}, {24}, {25}},
+    {{25}, {26}, {27}},
+    {{25}, {27}, {28}},
+    {{21}, {23}, {25}},
+    {{31}, {34}, { 4}},
+    {{30}, {31}, { 4}},
+    {{16}, {21}, {25}},
+    {{16}, {25}, {28}},
+    {{29}, {30}, { 4}},
+    {{ 4}, {16}, {28}},
+    {{40}, {39}, {45}},
+    {{45}, {46}, {47}},
+    {{47}, {48}, {49}},
+    {{49}, {50}, {51}},
+    {{51}, {52}, {53}},
+    {{53}, {54}, {55}},
+    {{56}, {57}, {58}},
+    {{53}, {55}, {56}},
+    {{49}, {51}, {53}},
+    {{45}, {47}, {49}},
+    {{42}, {41}, {40}},
+    {{40}, {45}, {49}},
+    {{49}, {53}, {56}},
+    {{56}, {58}, {59}},
+    {{59}, {60}, {61}},
+    {{62}, {63}, {64}},
+    {{59}, {61}, {62}},
+    {{49}, {56}, {59}},
+    {{43}, {42}, {40}},
+    {{49}, {59}, {62}},
+    {{62}, {64}, {65}},
+    {{49}, {62}, {65}},
+    {{44}, {43}, {40}},
+    {{40}, {49}, {65}},
+    {{40}, {65}, {66}},
+    {{75}, {44}, {40}},
+    {{73}, {74}, {75}},
+    {{71}, {72}, {73}},
+    {{69}, {70}, {71}},
+    {{67}, {68}, {69}},
+    {{40}, {66}, {67}},
+    {{73}, {75}, {40}},
+    {{67}, {69}, {71}},
+    {{71}, {73}, {40}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/knight.obj b/chess/knight.obj
new file mode 100644
index 0000000..c7ce41a
--- /dev/null
+++ b/chess/knight.obj
@@ -0,0 +1,152 @@
+# Blender 3.3.6
+# www.blender.org
+o Knight
+v 0.659379 -0.816994 -0.500000
+v 0.562711 -0.484379 -0.500000
+v 0.619948 -0.544161 -0.500000
+v 0.660651 -0.653548 -0.500000
+v 0.514377 -0.460212 -0.500000
+v 0.590694 -0.167663 -0.500000
+v 0.590694 0.056200 -0.500000
+v 0.542359 0.227913 -0.500000
+v 0.452051 0.393266 -0.500000
+v 0.356655 0.496294 -0.500000
+v 0.214196 0.587875 -0.500000
+v 0.062834 0.643840 -0.500000
+v -0.031290 0.656560 -0.500000
+v -0.172476 0.799018 -0.500000
+v -0.250065 0.795203 -0.500000
+v -0.297128 0.739237 -0.500000
+v -0.317479 0.631121 -0.500000
+v -0.419235 0.531909 -0.500000
+v -0.477744 0.408530 -0.500000
+v -0.509543 0.313134 -0.500000
+v -0.706695 0.014225 -0.500000
+v -0.707967 -0.079899 -0.500000
+v -0.659633 -0.147312 -0.500000
+v -0.506999 -0.207094 -0.500000
+v -0.396340 -0.207094 -0.500000
+v -0.307303 -0.084987 -0.500000
+v -0.204275 -0.082443 -0.500000
+v -0.124142 -0.039196 -0.500000
+v -0.032562 0.048568 -0.500000
+v -0.035106 -0.015029 -0.500000
+v -0.077080 -0.078627 -0.500000
+v -0.206819 -0.181655 -0.500000
+v -0.295856 -0.277051 -0.500000
+v -0.363269 -0.378807 -0.500000
+v -0.386164 -0.457668 -0.500000
+v -0.462481 -0.495826 -0.500000
+v -0.510815 -0.551792 -0.500000
+v -0.534982 -0.626837 -0.500000
+v -0.534982 -0.816994 -0.500000
+v 0.500944 -0.156150 -1.500000
+v 0.409169 -0.507952 -1.500000
+v 0.508650 -0.557692 -1.500000
+v 0.542299 -0.592837 -1.500000
+v 0.570775 -0.669367 -1.500000
+v 0.570325 -0.744827 -1.500000
+v 0.500944 0.043809 -1.500000
+v 0.458720 0.193813 -1.500000
+v 0.378625 0.340467 -1.500000
+v 0.298539 0.426959 -1.500000
+v 0.173894 0.507088 -1.500000
+v 0.040999 0.556225 -1.500000
+v -0.073553 0.571706 -1.500000
+v -0.209298 0.704796 -1.500000
+v -0.234523 0.586654 -1.500000
+v -0.345045 0.478895 -1.500000
+v -0.394320 0.374988 -1.500000
+v -0.428129 0.273563 -1.500000
+v -0.617309 -0.013258 -1.500000
+v -0.617827 -0.051594 -1.500000
+v -0.602171 -0.073430 -1.500000
+v -0.490050 -0.117344 -1.500000
+v -0.441973 -0.117344 -1.500000
+v -0.353752 0.003644 -1.500000
+v -0.227982 0.006749 -1.500000
+v -0.177465 0.034012 -1.500000
+v 0.029378 0.195605 -1.500000
+v 0.053573 -0.043600 -1.500000
+v -0.010058 -0.140010 -1.500000
+v -0.145769 -0.247781 -1.500000
+v -0.225155 -0.332837 -1.500000
+v -0.280893 -0.416969 -1.500000
+v -0.310917 -0.520388 -1.500000
+v -0.406289 -0.568074 -1.500000
+v -0.430974 -0.596657 -1.500000
+v -0.445232 -0.640932 -1.500000
+v -0.445232 -0.744827 -1.500000
+s 0
+f 5 29 30
+f 41 68 72
+f 5 6 7
+f 7 8 9
+f 9 10 11
+f 11 12 13
+f 13 14 15
+f 15 16 17
+f 17 18 19
+f 20 21 22
+f 17 19 20
+f 13 15 17
+f 9 11 13
+f 5 7 9
+f 3 2 5
+f 1 4 3
+f 38 39 1
+f 36 37 38
+f 33 34 35
+f 35 36 38
+f 38 1 3
+f 5 9 13
+f 38 3 5
+f 32 33 35
+f 35 38 5
+f 5 13 17
+f 17 20 22
+f 22 23 24
+f 24 25 26
+f 26 27 28
+f 26 28 29
+f 22 24 26
+f 32 35 5
+f 31 32 5
+f 17 22 26
+f 17 26 29
+f 30 31 5
+f 5 17 29
+f 41 40 46
+f 46 47 48
+f 48 49 50
+f 50 51 52
+f 52 53 54
+f 54 55 56
+f 57 58 59
+f 54 56 57
+f 50 52 54
+f 46 48 50
+f 43 42 41
+f 41 46 50
+f 50 54 57
+f 57 59 60
+f 60 61 62
+f 63 64 65
+f 60 62 63
+f 50 57 60
+f 44 43 41
+f 50 60 63
+f 63 65 66
+f 50 63 66
+f 45 44 41
+f 41 50 66
+f 41 66 67
+f 76 45 41
+f 74 75 76
+f 72 73 74
+f 70 71 72
+f 68 69 70
+f 41 67 68
+f 74 76 41
+f 68 70 72
+f 72 74 41
diff --git a/chess/main.cpp b/chess/main.cpp
new file mode 100644
index 0000000..57a1f68
--- /dev/null
+++ b/chess/main.cpp
@@ -0,0 +1,140 @@
+#include <bit>
+
+#include "memorymap.hpp"
+#include "twiddle.hpp"
+
+#include "holly/texture_memory_alloc.hpp"
+#include "holly/holly.hpp"
+#include "holly/core.hpp"
+#include "holly/core_bits.hpp"
+#include "holly/ta_fifo_polygon_converter.hpp"
+#include "holly/ta_parameter.hpp"
+#include "holly/ta_global_parameter.hpp"
+#include "holly/ta_vertex_parameter.hpp"
+#include "holly/ta_bits.hpp"
+#include "holly/isp_tsp.hpp"
+#include "holly/region_array.hpp"
+#include "holly/background.hpp"
+#include "holly/video_output.hpp"
+
+#include "maple/maple_bus_bits.hpp"
+
+#include "sh7091/store_queue.hpp"
+#include "sh7091/serial.hpp"
+
+#include "render.hpp"
+#include "input.hpp"
+
+struct button {
+  bool a;
+  bool b;
+};
+
+struct cursor {
+  float x;
+  float y;
+  struct button button[2];
+};
+
+void cursor_update(chess::game_state& game_state, struct cursor& cursor, uint32_t frame_ix)
+{
+  for (int port_ix = 0; port_ix < 4; port_ix++) {
+    auto& port = input::state.port[port_ix];
+    if (port.function_type & function_type::controller) {
+
+    }
+    if (port.function_type & function_type::pointing) {
+      auto& bus_data = port.host_response_data_transfer_ft9->bus_data;
+      auto& data_fields = bus_data.data_fields;
+      if (std::byteswap(data_fields.function_type) & function_type::pointing) {
+	auto& data = data_fields.data;
+	cursor.x += static_cast<float>(data.analog_coordinate_axis[0] - 0x200) *  0.0035;
+	cursor.y += static_cast<float>(data.analog_coordinate_axis[1] - 0x200) * -0.0035;
+	cursor.button[frame_ix].a = ft9::data_transfer::button::a(data.button) == 0;
+	cursor.button[frame_ix].b = ft9::data_transfer::button::b(data.button) == 0;
+      }
+    }
+  }
+
+  uint32_t last_frame = (frame_ix + 1) & 1;
+  if (cursor.button[last_frame].a != cursor.button[frame_ix].a && cursor.button[frame_ix].a) {
+    int8_t x = cursor.x + 0.5f;
+    int8_t y = cursor.y + 0.5f;
+    chess::select_position(game_state, x, y);
+  }
+  if (cursor.button[last_frame].b != cursor.button[frame_ix].b && cursor.button[frame_ix].b) {
+    serial::string("b\n");
+  }
+}
+
+void main()
+{
+  video_output::set_mode_vga();
+
+  constexpr uint32_t ta_alloc = ta_alloc_ctrl::pt_opb::no_list
+                              | ta_alloc_ctrl::tm_opb::no_list
+                              | ta_alloc_ctrl::t_opb::no_list
+                              | ta_alloc_ctrl::om_opb::no_list
+                              | ta_alloc_ctrl::o_opb::_16x4byte;
+
+  constexpr struct opb_size opb_size = { .opaque = 16 * 4
+                                       , .opaque_modifier = 0
+                                       , .translucent = 0
+                                       , .translucent_modifier = 0
+                                       , .punch_through = 0
+                                       };
+
+  holly.SOFTRESET = softreset::pipeline_soft_reset
+                  | softreset::ta_soft_reset;
+  holly.SOFTRESET = 0;
+
+  core_init();
+  region_array2(640 / 32, 480 / 32, opb_size);
+  background_parameter(0xff0000ff);
+
+  chess::game_state game_state;
+  chess::game_init(game_state);
+
+  uint32_t send_buf[1024] __attribute__((aligned(32)));
+  uint32_t recv_buf[1024] __attribute__((aligned(32)));
+
+  input::state_init();
+
+  uint32_t frame_ix = 0;
+
+  struct cursor cursor;
+  cursor.x = 4.f;
+  cursor.y = 4.f;
+
+  while (true) {
+    input::state_update(send_buf, recv_buf);
+    cursor_update(game_state, cursor, frame_ix);
+
+    ta_polygon_converter_init(opb_size.total(),
+                              ta_alloc,
+                              640 / 32,
+                              480 / 32);
+
+    render::draw_board();
+    if (game_state.interaction.selected_position != -1)
+      render::draw_illumination(game_state.interaction.selected_position);
+    render::draw_pieces(game_state);
+    render::draw_moves(game_state.interaction.moves);
+    render::draw_cursor(cursor.x, cursor.y);
+
+    *reinterpret_cast<ta_global_parameter::end_of_list *>(store_queue) =
+      ta_global_parameter::end_of_list(para_control::para_type::end_of_list);
+    sq_transfer_32byte(ta_fifo_polygon_converter);
+
+    ta_wait_opaque_list();
+
+    core_start_render(frame_ix);
+    core_wait_end_of_render_video();
+
+    while (!spg_status::vsync(holly.SPG_STATUS));
+    core_flip(frame_ix);
+    while (spg_status::vsync(holly.SPG_STATUS));
+
+    frame_ix = (frame_ix + 1) & 1;
+  }
+}
diff --git a/chess/pawn.blend b/chess/pawn.blend
new file mode 100644
index 0000000..87c339e
Binary files /dev/null and b/chess/pawn.blend differ
diff --git a/chess/pawn.hpp b/chess/pawn.hpp
new file mode 100644
index 0000000..4bc94a1
--- /dev/null
+++ b/chess/pawn.hpp
@@ -0,0 +1,190 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace pawn {
+  constexpr vec3 vertices[] = {
+    {  0.501714f, -0.615807f, -0.500000f },
+    {  0.524680f, -0.696187f, -0.500000f },
+    {  0.525563f, -0.814549f, -0.500000f },
+    {  0.469032f, -0.542493f, -0.500000f },
+    {  0.399251f, -0.467413f, -0.500000f },
+    {  0.300322f, -0.402932f, -0.500000f },
+    {  0.234074f, -0.326085f, -0.500000f },
+    {  0.182843f, -0.218322f, -0.500000f },
+    {  0.167827f, -0.153841f, -0.500000f },
+    {  0.280889f, -0.154725f, -0.500000f },
+    {  0.302972f, -0.111443f, -0.500000f },
+    {  0.320638f, -0.068161f, -0.500000f },
+    {  0.317104f, -0.007214f, -0.500000f },
+    {  0.196976f,  0.073167f, -0.500000f },
+    {  0.228775f,  0.121748f, -0.500000f },
+    {  0.261457f,  0.188879f, -0.500000f },
+    {  0.274706f,  0.253360f, -0.500000f },
+    {  0.273823f,  0.315191f, -0.500000f },
+    {  0.257923f,  0.381438f, -0.500000f },
+    {  0.219942f,  0.445036f, -0.500000f },
+    {  0.173127f,  0.490084f, -0.500000f },
+    {  0.123662f,  0.520999f, -0.500000f },
+    {  0.053881f,  0.544848f, -0.500000f },
+    {  0.000000f,  0.552798f, -0.500000f },
+    { -0.501714f, -0.615807f, -0.500000f },
+    { -0.524680f, -0.696187f, -0.500000f },
+    { -0.525563f, -0.814549f, -0.500000f },
+    { -0.469032f, -0.542493f, -0.500000f },
+    { -0.399251f, -0.467413f, -0.500000f },
+    { -0.300322f, -0.402932f, -0.500000f },
+    { -0.234074f, -0.326085f, -0.500000f },
+    { -0.182843f, -0.218322f, -0.500000f },
+    { -0.167827f, -0.153841f, -0.500000f },
+    { -0.280889f, -0.154725f, -0.500000f },
+    { -0.302972f, -0.111443f, -0.500000f },
+    { -0.320638f, -0.068161f, -0.500000f },
+    { -0.317104f, -0.007214f, -0.500000f },
+    { -0.196976f,  0.073167f, -0.500000f },
+    { -0.228775f,  0.121748f, -0.500000f },
+    { -0.261457f,  0.188879f, -0.500000f },
+    { -0.274706f,  0.253360f, -0.500000f },
+    { -0.273823f,  0.315191f, -0.500000f },
+    { -0.257923f,  0.381438f, -0.500000f },
+    { -0.219942f,  0.445036f, -0.500000f },
+    { -0.173127f,  0.490084f, -0.500000f },
+    { -0.123662f,  0.520999f, -0.500000f },
+    { -0.053881f,  0.544848f, -0.500000f },
+    {  0.388761f, -0.595554f, -1.500000f },
+    {  0.411286f, -0.648695f, -1.500000f },
+    {  0.429437f, -0.709889f, -1.500000f },
+    {  0.431445f, -0.746821f, -1.500000f },
+    { -0.431445f, -0.746821f, -1.500000f },
+    { -0.429437f, -0.709889f, -1.500000f },
+    { -0.411286f, -0.648695f, -1.500000f },
+    { -0.388761f, -0.595554f, -1.500000f },
+    { -0.337277f, -0.541021f, -1.500000f },
+    { -0.236983f, -0.475369f, -1.500000f },
+    { -0.153462f, -0.378626f, -1.500000f },
+    { -0.092010f, -0.250075f, -1.500000f },
+    { -0.092699f, -0.093719f, -1.500000f },
+    { -0.230956f, -0.072472f, -1.500000f },
+    { -0.233576f, -0.054984f, -1.500000f },
+    { -0.102685f,  0.053978f, -1.500000f },
+    { -0.145094f,  0.169251f, -1.500000f },
+    { -0.170359f,  0.219865f, -1.500000f },
+    { -0.178909f,  0.262409f, -1.500000f },
+    { -0.178349f,  0.303202f, -1.500000f },
+    { -0.168815f,  0.345126f, -1.500000f },
+    { -0.144609f,  0.385169f, -1.500000f },
+    { -0.113949f,  0.414209f, -1.500000f },
+    { -0.082332f,  0.434104f, -1.500000f },
+    { -0.031205f,  0.451335f, -1.500000f },
+    {  0.000000f,  0.456575f, -1.500000f },
+    {  0.031205f,  0.451335f, -1.500000f },
+    {  0.082332f,  0.434104f, -1.500000f },
+    {  0.113949f,  0.414209f, -1.500000f },
+    {  0.144609f,  0.385169f, -1.500000f },
+    {  0.168815f,  0.345126f, -1.500000f },
+    {  0.178349f,  0.303202f, -1.500000f },
+    {  0.178909f,  0.262409f, -1.500000f },
+    {  0.170359f,  0.219865f, -1.500000f },
+    {  0.145094f,  0.169251f, -1.500000f },
+    {  0.102685f,  0.053978f, -1.500000f },
+    {  0.233576f, -0.054984f, -1.500000f },
+    {  0.230956f, -0.072472f, -1.500000f },
+    {  0.092699f, -0.093719f, -1.500000f },
+    {  0.092010f, -0.250075f, -1.500000f },
+    {  0.153462f, -0.378626f, -1.500000f },
+    {  0.236983f, -0.475369f, -1.500000f },
+    {  0.337277f, -0.541021f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{41}, {21}, {13}},
+    {{67}, {75}, {82}},
+    {{ 4}, { 3}, { 0}},
+    {{ 0}, { 1}, { 2}},
+    {{ 2}, {26}, {25}},
+    {{25}, {24}, {27}},
+    {{27}, {28}, {29}},
+    {{25}, {27}, {29}},
+    {{ 0}, { 2}, {25}},
+    {{ 5}, { 4}, { 0}},
+    {{ 5}, { 0}, {25}},
+    {{25}, {29}, {30}},
+    {{ 5}, {25}, {30}},
+    {{ 6}, { 5}, {30}},
+    {{ 6}, {30}, {31}},
+    {{ 7}, { 6}, {31}},
+    {{32}, {33}, {34}},
+    {{ 7}, {31}, {32}},
+    {{10}, { 9}, { 8}},
+    {{ 8}, { 7}, {32}},
+    {{32}, {34}, {35}},
+    {{35}, {36}, {37}},
+    {{37}, {38}, {39}},
+    {{39}, {40}, {41}},
+    {{41}, {42}, {43}},
+    {{43}, {44}, {45}},
+    {{45}, {46}, {23}},
+    {{23}, {22}, {21}},
+    {{21}, {20}, {19}},
+    {{19}, {18}, {17}},
+    {{17}, {16}, {15}},
+    {{15}, {14}, {13}},
+    {{13}, {12}, {11}},
+    {{11}, {10}, { 8}},
+    {{ 8}, {32}, {35}},
+    {{37}, {39}, {41}},
+    {{ 8}, {35}, {37}},
+    {{13}, {11}, { 8}},
+    {{17}, {15}, {13}},
+    {{21}, {19}, {17}},
+    {{45}, {23}, {21}},
+    {{41}, {43}, {45}},
+    {{ 8}, {37}, {41}},
+    {{21}, {17}, {13}},
+    {{13}, { 8}, {41}},
+    {{41}, {45}, {21}},
+    {{89}, {47}, {48}},
+    {{48}, {49}, {50}},
+    {{50}, {51}, {52}},
+    {{52}, {53}, {54}},
+    {{54}, {55}, {56}},
+    {{52}, {54}, {56}},
+    {{48}, {50}, {52}},
+    {{88}, {89}, {48}},
+    {{88}, {48}, {52}},
+    {{52}, {56}, {57}},
+    {{88}, {52}, {57}},
+    {{87}, {88}, {57}},
+    {{87}, {57}, {58}},
+    {{86}, {87}, {58}},
+    {{59}, {60}, {61}},
+    {{86}, {58}, {59}},
+    {{83}, {84}, {85}},
+    {{85}, {86}, {59}},
+    {{59}, {61}, {62}},
+    {{63}, {64}, {65}},
+    {{85}, {59}, {62}},
+    {{62}, {63}, {65}},
+    {{65}, {66}, {67}},
+    {{67}, {68}, {69}},
+    {{69}, {70}, {71}},
+    {{71}, {72}, {73}},
+    {{73}, {74}, {75}},
+    {{75}, {76}, {77}},
+    {{77}, {78}, {79}},
+    {{79}, {80}, {81}},
+    {{82}, {83}, {85}},
+    {{79}, {81}, {82}},
+    {{75}, {77}, {79}},
+    {{71}, {73}, {75}},
+    {{67}, {69}, {71}},
+    {{62}, {65}, {67}},
+    {{82}, {85}, {62}},
+    {{75}, {79}, {82}},
+    {{67}, {71}, {75}},
+    {{82}, {62}, {67}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/pawn.mtl b/chess/pawn.mtl
new file mode 100644
index 0000000..e465572
--- /dev/null
+++ b/chess/pawn.mtl
@@ -0,0 +1,12 @@
+# Blender 3.3.6 MTL File: 'pawn.blend'
+# www.blender.org
+
+newmtl Material
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
diff --git a/chess/pawn.obj b/chess/pawn.obj
new file mode 100644
index 0000000..208ad9a
--- /dev/null
+++ b/chess/pawn.obj
@@ -0,0 +1,180 @@
+# Blender 3.3.6
+# www.blender.org
+o Pawn
+v 0.501714 -0.615807 -0.500000
+v 0.524680 -0.696187 -0.500000
+v 0.525563 -0.814549 -0.500000
+v 0.469032 -0.542493 -0.500000
+v 0.399251 -0.467413 -0.500000
+v 0.300322 -0.402932 -0.500000
+v 0.234074 -0.326085 -0.500000
+v 0.182843 -0.218322 -0.500000
+v 0.167827 -0.153841 -0.500000
+v 0.280889 -0.154725 -0.500000
+v 0.302972 -0.111443 -0.500000
+v 0.320638 -0.068161 -0.500000
+v 0.317104 -0.007214 -0.500000
+v 0.196976 0.073167 -0.500000
+v 0.228775 0.121748 -0.500000
+v 0.261457 0.188879 -0.500000
+v 0.274706 0.253360 -0.500000
+v 0.273823 0.315191 -0.500000
+v 0.257923 0.381438 -0.500000
+v 0.219942 0.445036 -0.500000
+v 0.173127 0.490084 -0.500000
+v 0.123662 0.520999 -0.500000
+v 0.053881 0.544848 -0.500000
+v 0.000000 0.552798 -0.500000
+v -0.501714 -0.615807 -0.500000
+v -0.524680 -0.696187 -0.500000
+v -0.525563 -0.814549 -0.500000
+v -0.469032 -0.542493 -0.500000
+v -0.399251 -0.467413 -0.500000
+v -0.300322 -0.402932 -0.500000
+v -0.234074 -0.326085 -0.500000
+v -0.182843 -0.218322 -0.500000
+v -0.167827 -0.153841 -0.500000
+v -0.280889 -0.154725 -0.500000
+v -0.302972 -0.111443 -0.500000
+v -0.320638 -0.068161 -0.500000
+v -0.317104 -0.007214 -0.500000
+v -0.196976 0.073167 -0.500000
+v -0.228775 0.121748 -0.500000
+v -0.261457 0.188879 -0.500000
+v -0.274706 0.253360 -0.500000
+v -0.273823 0.315191 -0.500000
+v -0.257923 0.381438 -0.500000
+v -0.219942 0.445036 -0.500000
+v -0.173127 0.490084 -0.500000
+v -0.123662 0.520999 -0.500000
+v -0.053881 0.544848 -0.500000
+v 0.388761 -0.595554 -1.500000
+v 0.411286 -0.648695 -1.500000
+v 0.429437 -0.709889 -1.500000
+v 0.431445 -0.746821 -1.500000
+v -0.431445 -0.746821 -1.500000
+v -0.429437 -0.709889 -1.500000
+v -0.411286 -0.648695 -1.500000
+v -0.388761 -0.595554 -1.500000
+v -0.337277 -0.541021 -1.500000
+v -0.236983 -0.475369 -1.500000
+v -0.153462 -0.378626 -1.500000
+v -0.092010 -0.250075 -1.500000
+v -0.092699 -0.093719 -1.500000
+v -0.230956 -0.072472 -1.500000
+v -0.233576 -0.054984 -1.500000
+v -0.102685 0.053978 -1.500000
+v -0.145094 0.169251 -1.500000
+v -0.170359 0.219865 -1.500000
+v -0.178909 0.262409 -1.500000
+v -0.178349 0.303202 -1.500000
+v -0.168815 0.345126 -1.500000
+v -0.144609 0.385169 -1.500000
+v -0.113949 0.414209 -1.500000
+v -0.082332 0.434104 -1.500000
+v -0.031205 0.451335 -1.500000
+v 0.000000 0.456575 -1.500000
+v 0.031205 0.451335 -1.500000
+v 0.082332 0.434104 -1.500000
+v 0.113949 0.414209 -1.500000
+v 0.144609 0.385169 -1.500000
+v 0.168815 0.345126 -1.500000
+v 0.178349 0.303202 -1.500000
+v 0.178909 0.262409 -1.500000
+v 0.170359 0.219865 -1.500000
+v 0.145094 0.169251 -1.500000
+v 0.102685 0.053978 -1.500000
+v 0.233576 -0.054984 -1.500000
+v 0.230956 -0.072472 -1.500000
+v 0.092699 -0.093719 -1.500000
+v 0.092010 -0.250075 -1.500000
+v 0.153462 -0.378626 -1.500000
+v 0.236983 -0.475369 -1.500000
+v 0.337277 -0.541021 -1.500000
+s 0
+f 42 22 14
+f 68 76 83
+f 5 4 1
+f 1 2 3
+f 3 27 26
+f 26 25 28
+f 28 29 30
+f 26 28 30
+f 1 3 26
+f 6 5 1
+f 6 1 26
+f 26 30 31
+f 6 26 31
+f 7 6 31
+f 7 31 32
+f 8 7 32
+f 33 34 35
+f 8 32 33
+f 11 10 9
+f 9 8 33
+f 33 35 36
+f 36 37 38
+f 38 39 40
+f 40 41 42
+f 42 43 44
+f 44 45 46
+f 46 47 24
+f 24 23 22
+f 22 21 20
+f 20 19 18
+f 18 17 16
+f 16 15 14
+f 14 13 12
+f 12 11 9
+f 9 33 36
+f 38 40 42
+f 9 36 38
+f 14 12 9
+f 18 16 14
+f 22 20 18
+f 46 24 22
+f 42 44 46
+f 9 38 42
+f 22 18 14
+f 14 9 42
+f 42 46 22
+f 90 48 49
+f 49 50 51
+f 51 52 53
+f 53 54 55
+f 55 56 57
+f 53 55 57
+f 49 51 53
+f 89 90 49
+f 89 49 53
+f 53 57 58
+f 89 53 58
+f 88 89 58
+f 88 58 59
+f 87 88 59
+f 60 61 62
+f 87 59 60
+f 84 85 86
+f 86 87 60
+f 60 62 63
+f 64 65 66
+f 86 60 63
+f 63 64 66
+f 66 67 68
+f 68 69 70
+f 70 71 72
+f 72 73 74
+f 74 75 76
+f 76 77 78
+f 78 79 80
+f 80 81 82
+f 83 84 86
+f 80 82 83
+f 76 78 80
+f 72 74 76
+f 68 70 72
+f 63 66 68
+f 83 86 63
+f 76 80 83
+f 68 72 76
+f 83 63 68
diff --git a/chess/queen.blend b/chess/queen.blend
new file mode 100644
index 0000000..b5d71a2
Binary files /dev/null and b/chess/queen.blend differ
diff --git a/chess/queen.hpp b/chess/queen.hpp
new file mode 100644
index 0000000..31ddd14
--- /dev/null
+++ b/chess/queen.hpp
@@ -0,0 +1,298 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace queen {
+  constexpr vec3 vertices[] = {
+    {  0.000000f, -0.817631f, -0.500000f },
+    {  0.570827f, -0.535257f, -0.500000f },
+    {  0.604407f, -0.622259f, -0.500000f },
+    {  0.601354f, -0.817631f, -0.500000f },
+    {  0.500616f, -0.480309f, -0.500000f },
+    {  0.436509f, -0.457414f, -0.500000f },
+    {  0.671566f,  0.113438f, -0.500000f },
+    {  0.729567f,  0.137859f, -0.500000f },
+    {  0.769252f,  0.185176f, -0.500000f },
+    {  0.801050f,  0.252306f, -0.500000f },
+    {  0.800167f,  0.322970f, -0.500000f },
+    {  0.775435f,  0.383035f, -0.500000f },
+    {  0.725970f,  0.435149f, -0.500000f },
+    {  0.657073f,  0.463415f, -0.500000f },
+    {  0.579342f,  0.465181f, -0.500000f },
+    {  0.516628f,  0.435149f, -0.500000f },
+    {  0.468930f,  0.382151f, -0.500000f },
+    {  0.445081f,  0.321204f, -0.500000f },
+    {  0.444198f,  0.268206f, -0.500000f },
+    {  0.462747f,  0.220507f, -0.500000f },
+    {  0.337318f,  0.085363f, -0.500000f },
+    {  0.323186f,  0.436916f, -0.500000f },
+    {  0.365584f,  0.470481f, -0.500000f },
+    {  0.403566f,  0.520829f, -0.500000f },
+    {  0.424765f,  0.591493f, -0.500000f },
+    {  0.413282f,  0.672757f, -0.500000f },
+    {  0.368234f,  0.741654f, -0.500000f },
+    {  0.296687f,  0.776103f, -0.500000f },
+    {  0.252522f,  0.786702f, -0.500000f },
+    {  0.186274f,  0.777869f, -0.500000f },
+    {  0.115610f,  0.745187f, -0.500000f },
+    {  0.067912f,  0.690423f, -0.500000f },
+    {  0.052013f,  0.629475f, -0.500000f },
+    {  0.051129f,  0.560578f, -0.500000f },
+    {  0.072329f,  0.511113f, -0.500000f },
+    {  0.105894f,  0.477548f, -0.500000f },
+    {  0.000000f,  0.197542f, -0.500000f },
+    { -0.570827f, -0.535257f, -0.500000f },
+    { -0.604407f, -0.622259f, -0.500000f },
+    { -0.601354f, -0.817631f, -0.500000f },
+    { -0.500616f, -0.480309f, -0.500000f },
+    { -0.436509f, -0.457414f, -0.500000f },
+    { -0.671566f,  0.113438f, -0.500000f },
+    { -0.729567f,  0.137859f, -0.500000f },
+    { -0.769252f,  0.185176f, -0.500000f },
+    { -0.801050f,  0.252306f, -0.500000f },
+    { -0.800167f,  0.322970f, -0.500000f },
+    { -0.775435f,  0.383035f, -0.500000f },
+    { -0.725970f,  0.435149f, -0.500000f },
+    { -0.657073f,  0.463415f, -0.500000f },
+    { -0.579342f,  0.465181f, -0.500000f },
+    { -0.516628f,  0.435149f, -0.500000f },
+    { -0.468930f,  0.382151f, -0.500000f },
+    { -0.445081f,  0.321204f, -0.500000f },
+    { -0.444198f,  0.268206f, -0.500000f },
+    { -0.462747f,  0.220507f, -0.500000f },
+    { -0.337318f,  0.085363f, -0.500000f },
+    { -0.323186f,  0.436916f, -0.500000f },
+    { -0.365584f,  0.470481f, -0.500000f },
+    { -0.403566f,  0.520829f, -0.500000f },
+    { -0.424765f,  0.591493f, -0.500000f },
+    { -0.413282f,  0.672757f, -0.500000f },
+    { -0.368234f,  0.741654f, -0.500000f },
+    { -0.296687f,  0.776103f, -0.500000f },
+    { -0.252522f,  0.786702f, -0.500000f },
+    { -0.186274f,  0.777869f, -0.500000f },
+    { -0.115610f,  0.745187f, -0.500000f },
+    { -0.067912f,  0.690423f, -0.500000f },
+    { -0.052013f,  0.629475f, -0.500000f },
+    { -0.051129f,  0.560578f, -0.500000f },
+    { -0.072329f,  0.511113f, -0.500000f },
+    { -0.105894f,  0.477548f, -0.500000f },
+    {  0.462390f, -0.549696f, -1.500000f },
+    {  0.332972f, -0.503475f, -1.500000f },
+    {  0.505640f, -0.583544f, -1.500000f },
+    {  0.525978f, -0.636236f, -1.500000f },
+    {  0.524365f, -0.739429f, -1.500000f },
+    {  0.000000f, -0.739429f, -1.500000f },
+    {  0.611523f,  0.173007f, -1.500000f },
+    {  0.681798f,  0.202596f, -1.500000f },
+    {  0.702879f,  0.227731f, -1.500000f },
+    {  0.722629f,  0.269426f, -1.500000f },
+    {  0.722159f,  0.307031f, -1.500000f },
+    {  0.708676f,  0.339775f, -1.500000f },
+    {  0.680786f,  0.369160f, -1.500000f },
+    {  0.640803f,  0.385563f, -1.500000f },
+    {  0.596256f,  0.386576f, -1.500000f },
+    {  0.564385f,  0.371313f, -1.500000f },
+    {  0.536571f,  0.340409f, -1.500000f },
+    {  0.523037f,  0.305821f, -1.500000f },
+    {  0.522644f,  0.282247f, -1.500000f },
+    {  0.553382f,  0.203206f, -1.500000f },
+    {  0.266733f, -0.105648f, -1.500000f },
+    {  0.243449f,  0.473532f, -1.500000f },
+    {  0.309188f,  0.525576f, -1.500000f },
+    {  0.332692f,  0.556731f, -1.500000f },
+    {  0.344933f,  0.597535f, -1.500000f },
+    {  0.338289f,  0.644553f, -1.500000f },
+    {  0.314695f,  0.680638f, -1.500000f },
+    {  0.270300f,  0.702013f, -1.500000f },
+    {  0.248427f,  0.707263f, -1.500000f },
+    {  0.208351f,  0.701920f, -1.500000f },
+    {  0.163605f,  0.681225f, -1.500000f },
+    {  0.138945f,  0.652911f, -1.500000f },
+    {  0.130085f,  0.618950f, -1.500000f },
+    {  0.129537f,  0.576148f, -1.500000f },
+    {  0.138274f,  0.555761f, -1.500000f },
+    {  0.196906f,  0.497129f, -1.500000f },
+    {  0.000000f, -0.023532f, -1.500000f },
+    { -0.462390f, -0.549696f, -1.500000f },
+    { -0.332971f, -0.503475f, -1.500000f },
+    { -0.505640f, -0.583544f, -1.500000f },
+    { -0.525978f, -0.636236f, -1.500000f },
+    { -0.524365f, -0.739429f, -1.500000f },
+    { -0.611523f,  0.173007f, -1.500000f },
+    { -0.681798f,  0.202596f, -1.500000f },
+    { -0.702879f,  0.227731f, -1.500000f },
+    { -0.722629f,  0.269426f, -1.500000f },
+    { -0.722159f,  0.307031f, -1.500000f },
+    { -0.708676f,  0.339775f, -1.500000f },
+    { -0.680786f,  0.369160f, -1.500000f },
+    { -0.640803f,  0.385563f, -1.500000f },
+    { -0.596256f,  0.386576f, -1.500000f },
+    { -0.564385f,  0.371313f, -1.500000f },
+    { -0.536571f,  0.340409f, -1.500000f },
+    { -0.523037f,  0.305821f, -1.500000f },
+    { -0.522644f,  0.282247f, -1.500000f },
+    { -0.553382f,  0.203206f, -1.500000f },
+    { -0.266733f, -0.105648f, -1.500000f },
+    { -0.243449f,  0.473532f, -1.500000f },
+    { -0.309188f,  0.525576f, -1.500000f },
+    { -0.332692f,  0.556731f, -1.500000f },
+    { -0.344933f,  0.597535f, -1.500000f },
+    { -0.338289f,  0.644553f, -1.500000f },
+    { -0.314695f,  0.680638f, -1.500000f },
+    { -0.270300f,  0.702013f, -1.500000f },
+    { -0.248427f,  0.707263f, -1.500000f },
+    { -0.208351f,  0.701920f, -1.500000f },
+    { -0.163605f,  0.681225f, -1.500000f },
+    { -0.138945f,  0.652911f, -1.500000f },
+    { -0.130085f,  0.618950f, -1.500000f },
+    { -0.129537f,  0.576148f, -1.500000f },
+    { -0.138274f,  0.555761f, -1.500000f },
+    { -0.196906f,  0.497129f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{139}, {135}, {129}},
+    {{ 24}, { 36}, { 41}},
+    {{ 74}, { 72}, { 73}},
+    {{ 78}, { 79}, { 80}},
+    {{ 75}, { 74}, { 73}},
+    {{ 78}, { 80}, { 81}},
+    {{ 76}, { 75}, { 73}},
+    {{ 78}, { 81}, { 82}},
+    {{ 77}, { 76}, { 73}},
+    {{ 78}, { 82}, { 83}},
+    {{ 77}, { 73}, { 78}},
+    {{112}, {113}, { 77}},
+    {{109}, {111}, {112}},
+    {{110}, {109}, {112}},
+    {{ 77}, { 78}, { 83}},
+    {{ 83}, { 84}, { 85}},
+    {{ 85}, { 86}, { 87}},
+    {{ 87}, { 88}, { 89}},
+    {{ 89}, { 90}, { 91}},
+    {{ 87}, { 89}, { 91}},
+    {{ 83}, { 85}, { 87}},
+    {{110}, {112}, { 77}},
+    {{116}, {115}, {114}},
+    {{114}, {110}, { 77}},
+    {{ 83}, { 87}, { 91}},
+    {{ 83}, { 91}, { 92}},
+    {{117}, {116}, {114}},
+    {{119}, {118}, {117}},
+    {{121}, {120}, {119}},
+    {{123}, {122}, {121}},
+    {{125}, {124}, {123}},
+    {{127}, {126}, {125}},
+    {{127}, {125}, {123}},
+    {{123}, {121}, {119}},
+    {{119}, {117}, {114}},
+    {{ 77}, { 83}, { 92}},
+    {{ 93}, { 94}, { 95}},
+    {{ 77}, { 92}, { 93}},
+    {{119}, {114}, { 77}},
+    {{127}, {123}, {119}},
+    {{128}, {127}, {119}},
+    {{ 93}, { 95}, { 96}},
+    {{ 96}, { 97}, { 98}},
+    {{ 98}, { 99}, {100}},
+    {{100}, {101}, {102}},
+    {{102}, {103}, {104}},
+    {{104}, {105}, {106}},
+    {{104}, {106}, {107}},
+    {{100}, {102}, {104}},
+    {{ 96}, { 98}, {100}},
+    {{ 93}, { 96}, {100}},
+    {{100}, {104}, {107}},
+    {{ 93}, {100}, {107}},
+    {{128}, {119}, { 77}},
+    {{131}, {130}, {129}},
+    {{129}, {128}, { 77}},
+    {{ 77}, { 93}, {107}},
+    {{ 77}, {107}, {108}},
+    {{132}, {131}, {129}},
+    {{129}, { 77}, {108}},
+    {{143}, {142}, {141}},
+    {{129}, {108}, {143}},
+    {{133}, {132}, {129}},
+    {{135}, {134}, {133}},
+    {{137}, {136}, {135}},
+    {{139}, {138}, {137}},
+    {{141}, {140}, {139}},
+    {{129}, {143}, {141}},
+    {{135}, {133}, {129}},
+    {{139}, {137}, {135}},
+    {{129}, {141}, {139}},
+    {{  1}, {  4}, {  5}},
+    {{  6}, {  7}, {  8}},
+    {{  2}, {  1}, {  5}},
+    {{  6}, {  8}, {  9}},
+    {{  3}, {  2}, {  5}},
+    {{  6}, {  9}, { 10}},
+    {{  0}, {  3}, {  5}},
+    {{  6}, { 10}, { 11}},
+    {{  0}, {  5}, {  6}},
+    {{ 38}, { 39}, {  0}},
+    {{ 40}, { 37}, { 38}},
+    {{ 41}, { 40}, { 38}},
+    {{ 38}, {  0}, {  6}},
+    {{  6}, { 11}, { 12}},
+    {{ 12}, { 13}, { 14}},
+    {{ 14}, { 15}, { 16}},
+    {{ 16}, { 17}, { 18}},
+    {{ 16}, { 18}, { 19}},
+    {{ 12}, { 14}, { 16}},
+    {{ 41}, { 38}, {  6}},
+    {{ 44}, { 43}, { 42}},
+    {{  6}, { 12}, { 16}},
+    {{  6}, { 16}, { 19}},
+    {{ 45}, { 44}, { 42}},
+    {{ 47}, { 46}, { 45}},
+    {{ 49}, { 48}, { 47}},
+    {{ 51}, { 50}, { 49}},
+    {{ 53}, { 52}, { 51}},
+    {{ 55}, { 54}, { 53}},
+    {{ 55}, { 53}, { 51}},
+    {{ 51}, { 49}, { 47}},
+    {{ 47}, { 45}, { 42}},
+    {{  6}, { 19}, { 20}},
+    {{ 21}, { 22}, { 23}},
+    {{ 41}, {  6}, { 20}},
+    {{ 21}, { 23}, { 24}},
+    {{ 41}, { 20}, { 21}},
+    {{ 47}, { 42}, { 41}},
+    {{ 55}, { 51}, { 47}},
+    {{ 56}, { 55}, { 47}},
+    {{ 41}, { 21}, { 24}},
+    {{ 24}, { 25}, { 26}},
+    {{ 26}, { 27}, { 28}},
+    {{ 28}, { 29}, { 30}},
+    {{ 30}, { 31}, { 32}},
+    {{ 32}, { 33}, { 34}},
+    {{ 32}, { 34}, { 35}},
+    {{ 28}, { 30}, { 32}},
+    {{ 24}, { 26}, { 28}},
+    {{ 56}, { 47}, { 41}},
+    {{ 59}, { 58}, { 57}},
+    {{ 60}, { 59}, { 57}},
+    {{ 62}, { 61}, { 60}},
+    {{ 64}, { 63}, { 62}},
+    {{ 66}, { 65}, { 64}},
+    {{ 68}, { 67}, { 66}},
+    {{ 70}, { 69}, { 68}},
+    {{ 71}, { 70}, { 68}},
+    {{ 68}, { 66}, { 64}},
+    {{ 64}, { 62}, { 60}},
+    {{ 64}, { 60}, { 57}},
+    {{ 71}, { 68}, { 64}},
+    {{ 36}, { 71}, { 64}},
+    {{ 64}, { 57}, { 56}},
+    {{ 24}, { 28}, { 32}},
+    {{ 24}, { 32}, { 35}},
+    {{ 36}, { 64}, { 56}},
+    {{ 24}, { 35}, { 36}},
+    {{ 36}, { 56}, { 41}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/queen.obj b/chess/queen.obj
new file mode 100644
index 0000000..3eae5e0
--- /dev/null
+++ b/chess/queen.obj
@@ -0,0 +1,288 @@
+# Blender 3.3.6
+# www.blender.org
+o Queen
+v 0.000000 -0.817631 -0.500000
+v 0.570827 -0.535257 -0.500000
+v 0.604407 -0.622259 -0.500000
+v 0.601354 -0.817631 -0.500000
+v 0.500616 -0.480309 -0.500000
+v 0.436509 -0.457414 -0.500000
+v 0.671566 0.113438 -0.500000
+v 0.729567 0.137859 -0.500000
+v 0.769252 0.185176 -0.500000
+v 0.801050 0.252306 -0.500000
+v 0.800167 0.322970 -0.500000
+v 0.775435 0.383035 -0.500000
+v 0.725970 0.435149 -0.500000
+v 0.657073 0.463415 -0.500000
+v 0.579342 0.465181 -0.500000
+v 0.516628 0.435149 -0.500000
+v 0.468930 0.382151 -0.500000
+v 0.445081 0.321204 -0.500000
+v 0.444198 0.268206 -0.500000
+v 0.462747 0.220507 -0.500000
+v 0.337318 0.085363 -0.500000
+v 0.323186 0.436916 -0.500000
+v 0.365584 0.470481 -0.500000
+v 0.403566 0.520829 -0.500000
+v 0.424765 0.591493 -0.500000
+v 0.413282 0.672757 -0.500000
+v 0.368234 0.741654 -0.500000
+v 0.296687 0.776103 -0.500000
+v 0.252522 0.786702 -0.500000
+v 0.186274 0.777869 -0.500000
+v 0.115610 0.745187 -0.500000
+v 0.067912 0.690423 -0.500000
+v 0.052013 0.629475 -0.500000
+v 0.051129 0.560578 -0.500000
+v 0.072329 0.511113 -0.500000
+v 0.105894 0.477548 -0.500000
+v 0.000000 0.197542 -0.500000
+v -0.570827 -0.535257 -0.500000
+v -0.604407 -0.622259 -0.500000
+v -0.601354 -0.817631 -0.500000
+v -0.500616 -0.480309 -0.500000
+v -0.436509 -0.457414 -0.500000
+v -0.671566 0.113438 -0.500000
+v -0.729567 0.137859 -0.500000
+v -0.769252 0.185176 -0.500000
+v -0.801050 0.252306 -0.500000
+v -0.800167 0.322970 -0.500000
+v -0.775435 0.383035 -0.500000
+v -0.725970 0.435149 -0.500000
+v -0.657073 0.463415 -0.500000
+v -0.579342 0.465181 -0.500000
+v -0.516628 0.435149 -0.500000
+v -0.468930 0.382151 -0.500000
+v -0.445081 0.321204 -0.500000
+v -0.444198 0.268206 -0.500000
+v -0.462747 0.220507 -0.500000
+v -0.337318 0.085363 -0.500000
+v -0.323186 0.436916 -0.500000
+v -0.365584 0.470481 -0.500000
+v -0.403566 0.520829 -0.500000
+v -0.424765 0.591493 -0.500000
+v -0.413282 0.672757 -0.500000
+v -0.368234 0.741654 -0.500000
+v -0.296687 0.776103 -0.500000
+v -0.252522 0.786702 -0.500000
+v -0.186274 0.777869 -0.500000
+v -0.115610 0.745187 -0.500000
+v -0.067912 0.690423 -0.500000
+v -0.052013 0.629475 -0.500000
+v -0.051129 0.560578 -0.500000
+v -0.072329 0.511113 -0.500000
+v -0.105894 0.477548 -0.500000
+v 0.462390 -0.549696 -1.500000
+v 0.332972 -0.503475 -1.500000
+v 0.505640 -0.583544 -1.500000
+v 0.525978 -0.636236 -1.500000
+v 0.524365 -0.739429 -1.500000
+v 0.000000 -0.739429 -1.500000
+v 0.611523 0.173007 -1.500000
+v 0.681798 0.202596 -1.500000
+v 0.702879 0.227731 -1.500000
+v 0.722629 0.269426 -1.500000
+v 0.722159 0.307031 -1.500000
+v 0.708676 0.339775 -1.500000
+v 0.680786 0.369160 -1.500000
+v 0.640803 0.385563 -1.500000
+v 0.596256 0.386576 -1.500000
+v 0.564385 0.371313 -1.500000
+v 0.536571 0.340409 -1.500000
+v 0.523037 0.305821 -1.500000
+v 0.522644 0.282247 -1.500000
+v 0.553382 0.203206 -1.500000
+v 0.266733 -0.105648 -1.500000
+v 0.243449 0.473532 -1.500000
+v 0.309188 0.525576 -1.500000
+v 0.332692 0.556731 -1.500000
+v 0.344933 0.597535 -1.500000
+v 0.338289 0.644553 -1.500000
+v 0.314695 0.680638 -1.500000
+v 0.270300 0.702013 -1.500000
+v 0.248427 0.707263 -1.500000
+v 0.208351 0.701920 -1.500000
+v 0.163605 0.681225 -1.500000
+v 0.138945 0.652911 -1.500000
+v 0.130085 0.618950 -1.500000
+v 0.129537 0.576148 -1.500000
+v 0.138274 0.555761 -1.500000
+v 0.196906 0.497129 -1.500000
+v 0.000000 -0.023532 -1.500000
+v -0.462390 -0.549696 -1.500000
+v -0.332971 -0.503475 -1.500000
+v -0.505640 -0.583544 -1.500000
+v -0.525978 -0.636236 -1.500000
+v -0.524365 -0.739429 -1.500000
+v -0.611523 0.173007 -1.500000
+v -0.681798 0.202596 -1.500000
+v -0.702879 0.227731 -1.500000
+v -0.722629 0.269426 -1.500000
+v -0.722159 0.307031 -1.500000
+v -0.708676 0.339775 -1.500000
+v -0.680786 0.369160 -1.500000
+v -0.640803 0.385563 -1.500000
+v -0.596256 0.386576 -1.500000
+v -0.564385 0.371313 -1.500000
+v -0.536571 0.340409 -1.500000
+v -0.523037 0.305821 -1.500000
+v -0.522644 0.282247 -1.500000
+v -0.553382 0.203206 -1.500000
+v -0.266733 -0.105648 -1.500000
+v -0.243449 0.473532 -1.500000
+v -0.309188 0.525576 -1.500000
+v -0.332692 0.556731 -1.500000
+v -0.344933 0.597535 -1.500000
+v -0.338289 0.644553 -1.500000
+v -0.314695 0.680638 -1.500000
+v -0.270300 0.702013 -1.500000
+v -0.248427 0.707263 -1.500000
+v -0.208351 0.701920 -1.500000
+v -0.163605 0.681225 -1.500000
+v -0.138945 0.652911 -1.500000
+v -0.130085 0.618950 -1.500000
+v -0.129537 0.576148 -1.500000
+v -0.138274 0.555761 -1.500000
+v -0.196906 0.497129 -1.500000
+s 0
+f 140 136 130
+f 25 37 42
+f 75 73 74
+f 79 80 81
+f 76 75 74
+f 79 81 82
+f 77 76 74
+f 79 82 83
+f 78 77 74
+f 79 83 84
+f 78 74 79
+f 113 114 78
+f 110 112 113
+f 111 110 113
+f 78 79 84
+f 84 85 86
+f 86 87 88
+f 88 89 90
+f 90 91 92
+f 88 90 92
+f 84 86 88
+f 111 113 78
+f 117 116 115
+f 115 111 78
+f 84 88 92
+f 84 92 93
+f 118 117 115
+f 120 119 118
+f 122 121 120
+f 124 123 122
+f 126 125 124
+f 128 127 126
+f 128 126 124
+f 124 122 120
+f 120 118 115
+f 78 84 93
+f 94 95 96
+f 78 93 94
+f 120 115 78
+f 128 124 120
+f 129 128 120
+f 94 96 97
+f 97 98 99
+f 99 100 101
+f 101 102 103
+f 103 104 105
+f 105 106 107
+f 105 107 108
+f 101 103 105
+f 97 99 101
+f 94 97 101
+f 101 105 108
+f 94 101 108
+f 129 120 78
+f 132 131 130
+f 130 129 78
+f 78 94 108
+f 78 108 109
+f 133 132 130
+f 130 78 109
+f 144 143 142
+f 130 109 144
+f 134 133 130
+f 136 135 134
+f 138 137 136
+f 140 139 138
+f 142 141 140
+f 130 144 142
+f 136 134 130
+f 140 138 136
+f 130 142 140
+f 2 5 6
+f 7 8 9
+f 3 2 6
+f 7 9 10
+f 4 3 6
+f 7 10 11
+f 1 4 6
+f 7 11 12
+f 1 6 7
+f 39 40 1
+f 41 38 39
+f 42 41 39
+f 39 1 7
+f 7 12 13
+f 13 14 15
+f 15 16 17
+f 17 18 19
+f 17 19 20
+f 13 15 17
+f 42 39 7
+f 45 44 43
+f 7 13 17
+f 7 17 20
+f 46 45 43
+f 48 47 46
+f 50 49 48
+f 52 51 50
+f 54 53 52
+f 56 55 54
+f 56 54 52
+f 52 50 48
+f 48 46 43
+f 7 20 21
+f 22 23 24
+f 42 7 21
+f 22 24 25
+f 42 21 22
+f 48 43 42
+f 56 52 48
+f 57 56 48
+f 42 22 25
+f 25 26 27
+f 27 28 29
+f 29 30 31
+f 31 32 33
+f 33 34 35
+f 33 35 36
+f 29 31 33
+f 25 27 29
+f 57 48 42
+f 60 59 58
+f 61 60 58
+f 63 62 61
+f 65 64 63
+f 67 66 65
+f 69 68 67
+f 71 70 69
+f 72 71 69
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+f 25 29 33
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+f 25 36 37
+f 37 57 42
diff --git a/chess/render.cpp b/chess/render.cpp
new file mode 100644
index 0000000..fd123b4
--- /dev/null
+++ b/chess/render.cpp
@@ -0,0 +1,219 @@
+#include "chess/bishop.hpp"
+#include "chess/king.hpp"
+#include "chess/knight.hpp"
+#include "chess/pawn.hpp"
+#include "chess/queen.hpp"
+#include "chess/rook.hpp"
+#include "chess/square.hpp"
+#include "chess/circle.hpp"
+#include "chess/cursor.hpp"
+
+#include "sh7091/store_queue.hpp"
+#include "sh7091/serial.hpp"
+
+#include "holly/ta_parameter.hpp"
+#include "holly/isp_tsp.hpp"
+#include "holly/ta_global_parameter.hpp"
+#include "holly/ta_vertex_parameter.hpp"
+
+#include "render.hpp"
+
+namespace render {
+
+static inline vec3 transform(const vec3 v, float cell_x, float cell_y, float scale)
+{
+  float x = v.x * 28.f * scale;
+  float y = -v.y * 28.f * scale;
+  x += 124.f + cell_x * 56.f;
+  y +=  44.f + (7 - cell_y) * 56.f;
+
+  return {x, y, 1.f/(v.z + 10.0f)};
+}
+
+static void draw_model(vec3 const * const vertices,
+		       face_v const * const faces,
+		       uint32_t num_faces,
+		       uint32_t base_color,
+		       float cell_x,
+		       float cell_y,
+		       float scale,
+		       bool always)
+{
+  const uint32_t parameter_control_word = para_control::para_type::polygon_or_modifier_volume
+                                        | para_control::list_type::opaque
+                                        | obj_control::col_type::packed_color;
+
+  const uint32_t isp_tsp_instruction_word = (always ? isp_tsp_instruction_word::depth_compare_mode::always
+					            : isp_tsp_instruction_word::depth_compare_mode::greater)
+                                          | isp_tsp_instruction_word::culling_mode::no_culling;
+
+  const uint32_t tsp_instruction_word = tsp_instruction_word::src_alpha_instr::one
+                                      | tsp_instruction_word::dst_alpha_instr::zero
+                                      | tsp_instruction_word::fog_control::no_fog;
+
+
+  for (uint32_t face_ix = 0; face_ix < num_faces; face_ix++) {
+
+    *reinterpret_cast<ta_global_parameter::polygon_type_0 *>(store_queue) =
+      ta_global_parameter::polygon_type_0(parameter_control_word,
+					  isp_tsp_instruction_word,
+					  tsp_instruction_word,
+					  0, // texture_control_word
+					  0, // data_size_for_sort_dma
+					  0  // next_address_for_sort_dma
+					  );
+    sq_transfer_32byte(ta_fifo_polygon_converter);
+
+    auto& face = faces[face_ix];
+
+    constexpr uint32_t strip_length = 3;
+    for (uint32_t i = 0; i < strip_length; i++) {
+      uint32_t vertex_ix = face[i].vertex;
+      const auto vertex = transform(vertices[vertex_ix], cell_x, cell_y, scale);
+
+      bool end_of_strip = i == strip_length - 1;
+      float z = __builtin_fabsf(vertices[vertex_ix].z);
+      uint32_t color = (z < 0.9f && z > 0.1f) ? 0xff000000 : base_color;
+      *reinterpret_cast<ta_vertex_parameter::polygon_type_0 *>(store_queue) =
+	ta_vertex_parameter::polygon_type_0(polygon_vertex_parameter_control_word(end_of_strip),
+					    vertex.x, vertex.y, vertex.z,
+					    color);
+      sq_transfer_32byte(ta_fifo_polygon_converter);
+    }
+  }
+}
+
+void draw_board()
+{
+  for (int i = 0; i < 8 * 8; i++) {
+    int x = i % 8;
+    int y = i / 8;
+    bool white = (x % 2 == 0) ^ (y % 2 == 0);
+
+    constexpr uint32_t cream = 0xffebecd0;
+    constexpr uint32_t green = 0xff739552;
+    uint32_t color = white ? cream : green;
+
+    draw_model(square::vertices,
+	       square::faces,
+	       square::num_faces,
+	       color,
+	       x, y,
+	       1.0f,  // scale
+	       true); // always
+
+  }
+}
+
+void draw_illumination(int8_t position)
+{
+  auto [x, y] = chess::position_to_xy(position);
+
+  constexpr uint32_t cream = 0xfff5f681;
+  draw_model(square::vertices,
+	     square::faces,
+	     square::num_faces,
+	     cream,
+	     x, y,
+	     1.0f,  // scale
+	     true); // always
+}
+
+void draw_moves(chess::moves_list& moves)
+{
+  for (int i = 0; i < moves.length; i++) {
+    chess::xy move_xy = chess::position_to_xy(moves.moves[i].to_position);
+
+    uint32_t color = 0xff777777;
+    draw_model(circle::vertices,
+	       circle::faces,
+	       circle::num_faces,
+	       color,
+	       move_xy.x, move_xy.y,
+	       0.5f,  // scale
+	       true); // always
+  }
+}
+
+void draw_piece(int8_t type, int8_t x, int8_t y)
+{
+  bool white = type > 0;
+  uint32_t color = white ? 0xffdddddd : 0xff444444;
+  switch (__builtin_abs(type)) {
+  case chess::piece_type::pawn:
+    draw_model(pawn::vertices,
+	       pawn::faces,
+	       pawn::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  case chess::piece_type::knight:
+    draw_model(knight::vertices,
+	       knight::faces,
+	       knight::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  case chess::piece_type::bishop:
+    draw_model(bishop::vertices,
+	       bishop::faces,
+	       bishop::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  case chess::piece_type::rook:
+    draw_model(rook::vertices,
+	       rook::faces,
+	       rook::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  case chess::piece_type::queen:
+    draw_model(queen::vertices,
+	       queen::faces,
+	       queen::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  case chess::piece_type::king:
+    draw_model(king::vertices,
+	       king::faces,
+	       king::num_faces,
+	       color, x, y,
+	       1.0f,  // scale
+	       false); // always
+    break;
+  default:
+    break;
+  }
+}
+
+void draw_pieces(const chess::game_state& game_state)
+{
+  const auto& piece_list = game_state.piece_list;
+  for (int i = 0; i < piece_list.length; i++) {
+    chess::piece * piece = piece_list.piece[i];
+    int8_t position = piece_list_to_position(game_state.board, piece);
+    auto [x, y] = chess::position_to_xy(position);
+    draw_piece(piece->type, x, y);
+  }
+}
+
+void draw_cursor(float x, float y)
+{
+  uint32_t color = 0xffff00ff;
+  draw_model(cursor::vertices,
+	     cursor::faces,
+	     cursor::num_faces,
+	     color,
+	     x, y,
+	     1.0f,  // scale
+	     true); // always
+}
+
+} // namespace render
diff --git a/chess/render.hpp b/chess/render.hpp
new file mode 100644
index 0000000..01c663c
--- /dev/null
+++ b/chess/render.hpp
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <cstdint>
+
+#include "chess.hpp"
+
+namespace render {
+
+void draw_board();
+void draw_illumination(int8_t position);
+void draw_moves(chess::moves_list& moves);
+void draw_pieces(const chess::game_state& game_state);
+void draw_cursor(float x, float y);
+
+}
diff --git a/chess/rook.blend b/chess/rook.blend
new file mode 100644
index 0000000..9f641de
Binary files /dev/null and b/chess/rook.blend differ
diff --git a/chess/rook.hpp b/chess/rook.hpp
new file mode 100644
index 0000000..0f0ac01
--- /dev/null
+++ b/chess/rook.hpp
@@ -0,0 +1,150 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace rook {
+  constexpr vec3 vertices[] = {
+    {  0.586848f, -0.813234f, -0.500000f },
+    {  0.510530f, -0.501607f, -0.500000f },
+    {  0.560137f, -0.549941f, -0.500000f },
+    {  0.585576f, -0.632617f, -0.500000f },
+    {  0.430398f, -0.463448f, -0.500000f },
+    {  0.350265f,  0.154720f, -0.500000f },
+    {  0.411318f,  0.186519f, -0.500000f },
+    {  0.453293f,  0.236125f, -0.500000f },
+    {  0.477460f,  0.295906f, -0.500000f },
+    {  0.502899f,  0.578279f, -0.500000f },
+    {  0.438029f,  0.613894f, -0.500000f },
+    {  0.354081f,  0.636789f, -0.500000f },
+    {  0.271404f,  0.639333f, -0.500000f },
+    {  0.226885f,  0.458716f, -0.500000f },
+    {  0.169648f,  0.461260f, -0.500000f },
+    {  0.144209f,  0.662228f, -0.500000f },
+    {  0.071708f,  0.676220f, -0.500000f },
+    { -0.586848f, -0.813234f, -0.500000f },
+    { -0.510530f, -0.501607f, -0.500000f },
+    { -0.560137f, -0.549941f, -0.500000f },
+    { -0.585576f, -0.632617f, -0.500000f },
+    { -0.430398f, -0.463448f, -0.500000f },
+    { -0.350265f,  0.154720f, -0.500000f },
+    { -0.411318f,  0.186519f, -0.500000f },
+    { -0.453293f,  0.236125f, -0.500000f },
+    { -0.477460f,  0.295906f, -0.500000f },
+    { -0.502899f,  0.578279f, -0.500000f },
+    { -0.438029f,  0.613894f, -0.500000f },
+    { -0.354081f,  0.636789f, -0.500000f },
+    { -0.271404f,  0.639333f, -0.500000f },
+    { -0.226885f,  0.458716f, -0.500000f },
+    { -0.169648f,  0.461260f, -0.500000f },
+    { -0.144209f,  0.662228f, -0.500000f },
+    { -0.071708f,  0.676220f, -0.500000f },
+    {  0.000000f,  0.680318f, -0.500000f },
+    {  0.351645f, -0.520584f, -1.500000f },
+    {  0.257857f,  0.202929f, -1.500000f },
+    {  0.461029f, -0.572671f, -1.500000f },
+    {  0.484886f, -0.595916f, -1.500000f },
+    {  0.500222f, -0.645759f, -1.500000f },
+    {  0.500800f, -0.740978f, -1.500000f },
+    {  0.356946f,  0.254538f, -1.500000f },
+    {  0.379213f,  0.280854f, -1.500000f },
+    {  0.393497f,  0.316187f, -1.500000f },
+    {  0.412785f,  0.530280f, -1.500000f },
+    {  0.405782f,  0.534124f, -1.500000f },
+    {  0.341350f,  0.551697f, -1.500000f },
+    {  0.337831f,  0.551805f, -1.500000f },
+    {  0.293080f,  0.370246f, -1.500000f },
+    {  0.093922f,  0.379098f, -1.500000f },
+    {  0.067218f,  0.590066f, -1.500000f },
+    {  0.061127f,  0.591241f, -1.500000f },
+    { -0.351645f, -0.520584f, -1.500000f },
+    { -0.257857f,  0.202929f, -1.500000f },
+    { -0.461029f, -0.572671f, -1.500000f },
+    { -0.484886f, -0.595916f, -1.500000f },
+    { -0.500222f, -0.645759f, -1.500000f },
+    { -0.500800f, -0.740978f, -1.500000f },
+    { -0.356946f,  0.254538f, -1.500000f },
+    { -0.379213f,  0.280854f, -1.500000f },
+    { -0.393497f,  0.316187f, -1.500000f },
+    { -0.412785f,  0.530280f, -1.500000f },
+    { -0.405782f,  0.534124f, -1.500000f },
+    { -0.341350f,  0.551697f, -1.500000f },
+    { -0.337831f,  0.551805f, -1.500000f },
+    { -0.293080f,  0.370246f, -1.500000f },
+    { -0.093922f,  0.379098f, -1.500000f },
+    { -0.067218f,  0.590066f, -1.500000f },
+    { -0.061127f,  0.591241f, -1.500000f },
+    {  0.000000f,  0.594735f, -1.500000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{65}, {61}, {53}},
+    {{28}, {24}, {22}},
+    {{36}, {41}, {42}},
+    {{42}, {43}, {44}},
+    {{44}, {45}, {46}},
+    {{46}, {47}, {48}},
+    {{49}, {50}, {51}},
+    {{44}, {46}, {48}},
+    {{49}, {51}, {69}},
+    {{42}, {44}, {48}},
+    {{49}, {69}, {68}},
+    {{42}, {48}, {49}},
+    {{36}, {42}, {49}},
+    {{49}, {68}, {67}},
+    {{49}, {67}, {66}},
+    {{35}, {36}, {49}},
+    {{38}, {37}, {35}},
+    {{40}, {39}, {38}},
+    {{56}, {57}, {40}},
+    {{54}, {55}, {56}},
+    {{52}, {54}, {56}},
+    {{56}, {40}, {38}},
+    {{35}, {49}, {66}},
+    {{56}, {38}, {35}},
+    {{52}, {56}, {35}},
+    {{35}, {66}, {65}},
+    {{65}, {64}, {63}},
+    {{63}, {62}, {61}},
+    {{61}, {60}, {59}},
+    {{59}, {58}, {53}},
+    {{53}, {52}, {35}},
+    {{65}, {63}, {61}},
+    {{53}, {35}, {65}},
+    {{61}, {59}, {53}},
+    {{ 5}, { 6}, { 7}},
+    {{ 7}, { 8}, { 9}},
+    {{ 9}, {10}, {11}},
+    {{11}, {12}, {13}},
+    {{14}, {15}, {16}},
+    {{ 9}, {11}, {13}},
+    {{14}, {16}, {34}},
+    {{ 7}, { 9}, {13}},
+    {{14}, {34}, {33}},
+    {{ 7}, {13}, {14}},
+    {{ 5}, { 7}, {14}},
+    {{14}, {33}, {32}},
+    {{14}, {32}, {31}},
+    {{ 4}, { 5}, {14}},
+    {{ 2}, { 1}, { 4}},
+    {{ 0}, { 3}, { 2}},
+    {{20}, {17}, { 0}},
+    {{18}, {19}, {20}},
+    {{21}, {18}, {20}},
+    {{20}, { 0}, { 2}},
+    {{ 4}, {14}, {31}},
+    {{20}, { 2}, { 4}},
+    {{21}, {20}, { 4}},
+    {{ 4}, {31}, {30}},
+    {{30}, {29}, {28}},
+    {{28}, {27}, {26}},
+    {{26}, {25}, {24}},
+    {{24}, {23}, {22}},
+    {{22}, {21}, { 4}},
+    {{ 4}, {30}, {28}},
+    {{28}, {26}, {24}},
+    {{22}, { 4}, {28}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/rook.obj b/chess/rook.obj
new file mode 100644
index 0000000..f98a44e
--- /dev/null
+++ b/chess/rook.obj
@@ -0,0 +1,140 @@
+# Blender 3.3.6
+# www.blender.org
+o Rook
+v 0.586848 -0.813234 -0.500000
+v 0.510530 -0.501607 -0.500000
+v 0.560137 -0.549941 -0.500000
+v 0.585576 -0.632617 -0.500000
+v 0.430398 -0.463448 -0.500000
+v 0.350265 0.154720 -0.500000
+v 0.411318 0.186519 -0.500000
+v 0.453293 0.236125 -0.500000
+v 0.477460 0.295906 -0.500000
+v 0.502899 0.578279 -0.500000
+v 0.438029 0.613894 -0.500000
+v 0.354081 0.636789 -0.500000
+v 0.271404 0.639333 -0.500000
+v 0.226885 0.458716 -0.500000
+v 0.169648 0.461260 -0.500000
+v 0.144209 0.662228 -0.500000
+v 0.071708 0.676220 -0.500000
+v -0.586848 -0.813234 -0.500000
+v -0.510530 -0.501607 -0.500000
+v -0.560137 -0.549941 -0.500000
+v -0.585576 -0.632617 -0.500000
+v -0.430398 -0.463448 -0.500000
+v -0.350265 0.154720 -0.500000
+v -0.411318 0.186519 -0.500000
+v -0.453293 0.236125 -0.500000
+v -0.477460 0.295906 -0.500000
+v -0.502899 0.578279 -0.500000
+v -0.438029 0.613894 -0.500000
+v -0.354081 0.636789 -0.500000
+v -0.271404 0.639333 -0.500000
+v -0.226885 0.458716 -0.500000
+v -0.169648 0.461260 -0.500000
+v -0.144209 0.662228 -0.500000
+v -0.071708 0.676220 -0.500000
+v 0.000000 0.680318 -0.500000
+v 0.351645 -0.520584 -1.500000
+v 0.257857 0.202929 -1.500000
+v 0.461029 -0.572671 -1.500000
+v 0.484886 -0.595916 -1.500000
+v 0.500222 -0.645759 -1.500000
+v 0.500800 -0.740978 -1.500000
+v 0.356946 0.254538 -1.500000
+v 0.379213 0.280854 -1.500000
+v 0.393497 0.316187 -1.500000
+v 0.412785 0.530280 -1.500000
+v 0.405782 0.534124 -1.500000
+v 0.341350 0.551697 -1.500000
+v 0.337831 0.551805 -1.500000
+v 0.293080 0.370246 -1.500000
+v 0.093922 0.379098 -1.500000
+v 0.067218 0.590066 -1.500000
+v 0.061127 0.591241 -1.500000
+v -0.351645 -0.520584 -1.500000
+v -0.257857 0.202929 -1.500000
+v -0.461029 -0.572671 -1.500000
+v -0.484886 -0.595916 -1.500000
+v -0.500222 -0.645759 -1.500000
+v -0.500800 -0.740978 -1.500000
+v -0.356946 0.254538 -1.500000
+v -0.379213 0.280854 -1.500000
+v -0.393497 0.316187 -1.500000
+v -0.412785 0.530280 -1.500000
+v -0.405782 0.534124 -1.500000
+v -0.341350 0.551697 -1.500000
+v -0.337831 0.551805 -1.500000
+v -0.293080 0.370246 -1.500000
+v -0.093922 0.379098 -1.500000
+v -0.067218 0.590066 -1.500000
+v -0.061127 0.591241 -1.500000
+v 0.000000 0.594735 -1.500000
+s 0
+f 66 62 54
+f 29 25 23
+f 37 42 43
+f 43 44 45
+f 45 46 47
+f 47 48 49
+f 50 51 52
+f 45 47 49
+f 50 52 70
+f 43 45 49
+f 50 70 69
+f 43 49 50
+f 37 43 50
+f 50 69 68
+f 50 68 67
+f 36 37 50
+f 39 38 36
+f 41 40 39
+f 57 58 41
+f 55 56 57
+f 53 55 57
+f 57 41 39
+f 36 50 67
+f 57 39 36
+f 53 57 36
+f 36 67 66
+f 66 65 64
+f 64 63 62
+f 62 61 60
+f 60 59 54
+f 54 53 36
+f 66 64 62
+f 54 36 66
+f 62 60 54
+f 6 7 8
+f 8 9 10
+f 10 11 12
+f 12 13 14
+f 15 16 17
+f 10 12 14
+f 15 17 35
+f 8 10 14
+f 15 35 34
+f 8 14 15
+f 6 8 15
+f 15 34 33
+f 15 33 32
+f 5 6 15
+f 3 2 5
+f 1 4 3
+f 21 18 1
+f 19 20 21
+f 22 19 21
+f 21 1 3
+f 5 15 32
+f 21 3 5
+f 22 21 5
+f 5 32 31
+f 31 30 29
+f 29 28 27
+f 27 26 25
+f 25 24 23
+f 23 22 5
+f 5 31 29
+f 29 27 25
+f 23 5 29
diff --git a/chess/square.blend b/chess/square.blend
new file mode 100644
index 0000000..5b165e7
Binary files /dev/null and b/chess/square.blend differ
diff --git a/chess/square.hpp b/chess/square.hpp
new file mode 100644
index 0000000..4a97c01
--- /dev/null
+++ b/chess/square.hpp
@@ -0,0 +1,20 @@
+#pragma once
+
+#include "geometry/geometry.hpp"
+
+namespace square {
+  constexpr vec3 vertices[] = {
+    { -1.000000f,  1.000000f, -0.000000f },
+    {  1.000000f,  1.000000f, -0.000000f },
+    { -1.000000f, -1.000000f,  0.000000f },
+    {  1.000000f, -1.000000f,  0.000000f },
+  };
+
+  constexpr face_v faces[] = {
+    {{1}, {2}, {0}},
+    {{1}, {3}, {2}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_v));
+
+}
diff --git a/chess/square.obj b/chess/square.obj
new file mode 100644
index 0000000..e0d83a7
--- /dev/null
+++ b/chess/square.obj
@@ -0,0 +1,10 @@
+# Blender 3.3.6
+# www.blender.org
+o Square
+v -1.000000 1.000000 -0.000000
+v 1.000000 1.000000 -0.000000
+v -1.000000 -1.000000 0.000000
+v 1.000000 -1.000000 0.000000
+s 0
+f 2 3 1
+f 2 4 3
diff --git a/geometry/geometry.hpp b/geometry/geometry.hpp
index c511b09..2de40a6 100644
--- a/geometry/geometry.hpp
+++ b/geometry/geometry.hpp
@@ -24,6 +24,10 @@ struct vertex__normal {
   uint16_t normal;
 };
 
+struct vertex {
+  uint16_t vertex;
+};
+
 struct position__color {
   vec3 position;
   vec3 color;
@@ -32,3 +36,5 @@ struct position__color {
 using face_vtn = vertex__texture__normal[3];
 
 using face_vn = vertex__normal[3];
+
+using face_v = vertex[3];
diff --git a/tools/obj_to_cpp.py b/tools/obj_to_cpp.py
index 12e6418..7167468 100644
--- a/tools/obj_to_cpp.py
+++ b/tools/obj_to_cpp.py
@@ -25,6 +25,10 @@ class TextureCoordinate:
     u: float
     v: float
 
+@dataclass
+class VertexIx:
+    vertex: int
+
 @dataclass
 class VertexNormal:
     vertex: int
@@ -37,7 +41,8 @@ class VertexTextureNormal:
     normal: int
 
 Face = Union[tuple[VertexTextureNormal, VertexTextureNormal, VertexTextureNormal],
-             tuple[VertexNormal, VertexNormal, VertexNormal]]
+             tuple[VertexNormal, VertexNormal, VertexNormal],
+             tuple[VertexIx, VertexIx, VertexIx]]
 
 name = None
 
@@ -76,18 +81,21 @@ def parse_face(line):
     assert h == 'f'
     assert len(tri) == 3
     def parse_ixs(ixs):
-        ix = ixs.split('/')
-        assert len(ix) == 3
-        vertex_ix, uv_ix, normal_ix = [
-            maybe_int(iix, offset=-1)
-            for iix in ix
-        ]
-        assert vertex_ix is not None
-        assert normal_ix is not None
-        if uv_ix is None:
-            return VertexNormal(vertex_ix, normal_ix)
+        if '/' in ixs:
+            ix = ixs.split('/')
+            assert len(ix) == 3
+            vertex_ix, uv_ix, normal_ix = [
+                maybe_int(iix, offset=-1)
+                for iix in ix
+            ]
+            assert vertex_ix is not None
+            assert normal_ix is not None
+            if uv_ix is None:
+                return VertexNormal(vertex_ix, normal_ix)
+            else:
+                return VertexTextureNormal(vertex_ix, uv_ix, normal_ix)
         else:
-            return VertexTextureNormal(vertex_ix, uv_ix, normal_ix)
+            return VertexIx(int(ixs))
 
     return tuple(map(parse_ixs, tri))
 
@@ -130,7 +138,9 @@ def generate_texture_coordinates(texture_coordinates):
     yield ""
 
 def face_type_str(face_type):
-    if face_type is VertexNormal:
+    if face_type is VertexIx:
+        return "face_v"
+    elif face_type is VertexNormal:
         return "face_vn"
     elif face_type is VertexTextureNormal:
         return "face_vtn"
@@ -139,10 +149,12 @@ def face_type_str(face_type):
 
 def generate_faces(faces, face_type):
     def face_coords(vtn):
-        if face_type is VertexNormal:
-            return [vtn.vertex, vtn.normal]
+        if face_type is VertexIx:
+            return [vtn.vertex - 1]
+        elif face_type is VertexNormal:
+            return [vtn.vertex - 1, vtn.normal - 1]
         elif face_type is VertexTextureNormal:
-            return [vtn.vertex, vtn.texture, vtn.normal]
+            return [vtn.vertex - 1, vtn.texture - 1, vtn.normal - 1]
         else:
             assert False, face_type
     max_ix = max(
@@ -169,14 +181,15 @@ def generate_namespace(vertices, texture_coordinates, normals, faces, face_type)
     assert name is not None
     yield "#pragma once"
     yield ""
-    yield '#include "geometry.hpp"'
+    yield '#include "geometry/geometry.hpp"'
     yield ""
     yield f"namespace {name} {{"
 
     yield from generate_vertices(vertices)
     if texture_coordinates != []:
         yield from generate_texture_coordinates(texture_coordinates)
-    yield from generate_normals(normals)
+    if normals != []:
+        yield from generate_normals(normals)
     yield from generate_faces(faces, face_type)
 
     yield "}"