diff --git a/minecraft/configuration.idx b/minecraft/configuration.idx
index ef1ac34..58df8cc 100644
Binary files a/minecraft/configuration.idx and b/minecraft/configuration.idx differ
diff --git a/minecraft/gen/blocks.py b/minecraft/gen/blocks.py
index e877391..f50d99d 100644
--- a/minecraft/gen/blocks.py
+++ b/minecraft/gen/blocks.py
@@ -1,98 +1,7 @@
 import struct
 
-def id_to_px(i):
-    x = i % 16
-    y = i // 16
-    return x * 16, y * 16
-
-def px_to_id(px, py):
-    x = px // 16
-    y = py // 16
-    i = y * 16 + x
-    return i
-
 unk = 185
 
-mapping = [
-    (1, 1, "stone"),
-    (2, 0, "grass"),
-    (31, 0, "grass"), # fixme actually tallgrass
-    (3, 2, "dirt"),
-    (4, 16, "stonebrick"),
-    (5, 4, "wood"),
-    (6, 15, "sapling"),
-    (7, 17, "bedrock"),
-    (8, 205, "water"), # flowing
-    (9, 205, "water"), # still
-    (10, 237, "lava"), # flowing
-    (11, 237, "lava"), # still
-    (12, 18, "sand"),
-    (13, 19, "gravel"),
-    (14, 32, "oreGold"),
-    (15, 33, "oreIron"),
-    (16, 34, "oreCoal"),
-    (17, 20, "log"),
-    (18, 52, "leaves"),
-    (19, 48, "sponge"),
-    (20, 49, "glass"),
-    (35, 64, "cloth"),
-    (37, 13, "flower"),
-    (38, 12, "rose"),
-    (39, 29, "mushroom"),
-    (40, 28, "mushroom"),
-    (41, 39, "blockGold"),
-    (42, 38, "blockIron"),
-    (43, 5, "stoneSlab"), # double
-    (44, 5, "stoneSlab"), # single
-    (45, 7, "brick"),
-    (46, 8, "tnt"),
-    (47, 35, "bookshelf"),
-    (48, 36, "stoneMoss"),
-    (49, 37, "obsidian"),
-    (50, 80, "torch"),
-    (51, 31, "fire"),
-    (52, 65, "mobSpawner"),
-    (53, 4, "stairsWood"),
-    (54, 27, "chest"),
-    (55, 84, "redstoneDust"),
-    (56, 50, "oreDiamond"),
-    (57, 40, "blockDiamond"),
-    (58, 43, "workbench"),
-    (59, 88, "crops"),
-    (60, 87, "farmland"),
-    (61, 44, "furnace"), # off
-    (62, 61, "furnace"), # burning
-    (63, unk, "sign"),
-    (64, 81, "doorWood"),
-    (65, 83, "ladder"),
-    (66, 128, "rail"),
-    (67, 16, "stairsStone"),
-    (68, unk, "sign"),
-    (69, 96, "lever"),
-    (70, 6, "pressurePlate"),
-    (71, 82, "doorIron"),
-    (72, 6, "pressurePlate"),
-    (73, 51, "oreRedstone"),
-    (74, 51, "oreRedstone"),
-    (75, 115, "notGate"),
-    (76, 99, "notGate"),
-    (77, unk, "button"),
-    (78, 66, "snow"),
-    (79, 67, "ice"),
-    (80, 66, "snow"),
-    (81, 70, "cactus"),
-    (82, 72, "clay"),
-    (83, 73, "reeds"),
-    (84, 74, "jukebox"),
-    (85, 4, "fence"),
-    (86, 102, "pumpkin"),
-    (87, 103, "hellrock"),
-    (88, 104, "hellsand"),
-    (89, 105, "lightgem"),
-    (90, 14, "portal"),
-    (91, 102, "pumpkin"),
-]
-
 lookup = {
     k: v for k, v, _ in mapping
 }
diff --git a/minecraft/gen/cube.obj b/minecraft/gen/cube.obj
new file mode 100644
index 0000000..6b1c27f
--- /dev/null
+++ b/minecraft/gen/cube.obj
@@ -0,0 +1,36 @@
+# Blender 5.0.0
+# www.blender.org
+o Cube
+v 1.000000 1.000000 -1.000000
+v 1.000000 -1.000000 -1.000000
+v 1.000000 1.000000 1.000000
+v 1.000000 -1.000000 1.000000
+v -1.000000 1.000000 -1.000000
+v -1.000000 -1.000000 -1.000000
+v -1.000000 1.000000 1.000000
+v -1.000000 -1.000000 1.000000
+vn -0.0000 1.0000 -0.0000
+vn -0.0000 -0.0000 1.0000
+vn -1.0000 -0.0000 -0.0000
+vn -0.0000 -1.0000 -0.0000
+vn 1.0000 -0.0000 -0.0000
+vn -0.0000 -0.0000 -1.0000
+vt 1.000000 0.000000
+vt 0.000000 1.000000
+vt 0.000000 0.000000
+vt 1.000000 1.000000
+vt -0.000000 0.000000
+vt 1.000000 -0.000000
+s 0
+f 5/1/1 3/2/1 1/3/1
+f 3/4/2 8/5/2 4/6/2
+f 7/4/3 6/5/3 8/6/3
+f 2/1/4 8/2/4 6/3/4
+f 1/4/5 4/5/5 2/6/5
+f 5/4/6 2/5/6 6/6/6
+f 5/1/1 7/4/1 3/2/1
+f 3/4/2 7/2/2 8/5/2
+f 7/4/3 5/2/3 6/5/3
+f 2/1/4 4/4/4 8/2/4
+f 1/4/5 3/2/5 4/5/5
+f 5/4/6 1/2/6 2/5/6
diff --git a/minecraft/gen/cube.py b/minecraft/gen/cube.py
deleted file mode 100644
index c771311..0000000
--- a/minecraft/gen/cube.py
+++ /dev/null
@@ -1,134 +0,0 @@
-positions = [
-    (1.0, 1.0, -1.0),
-    (1.0, -1.0, -1.0),
-    (1.0, 1.0, 1.0),
-    (1.0, -1.0, 1.0),
-    (-1.0, 1.0, -1.0),
-    (-1.0, -1.0, -1.0),
-    (-1.0, 1.0, 1.0),
-    (-1.0, -1.0, 1.0)
-]
-
-normals = [
-  (0.0, 1.0, 0.0),
-  (0.0, 0.0, 1.0),
-  (-1.0, 0.0, 0.0),
-  (0.0, -1.0, 0.0),
-  (1.0, 0.0, 0.0),
-  (0.0, 0.0, -1.0),
-]
-
-textures = [
-  (1.0, 0.0),
-  (0.0, 1.0),
-  (0.0, 0.0),
-  (1.0, 1.0),
-  (0.0, 0.0),
-  (1.0, 0.0),
-]
-
-indices = [
-  [
-    [4, 0, 0],
-    [2, 1, 0],
-    [0, 2, 0],
-  ],
-  [
-    [2, 3, 1],
-    [7, 4, 1],
-    [3, 5, 1],
-  ],
-  [
-    [6, 3, 2],
-    [5, 4, 2],
-    [7, 5, 2],
-  ],
-  [
-    [1, 0, 3],
-    [7, 1, 3],
-    [5, 2, 3],
-  ],
-  [
-    [0, 3, 4],
-    [3, 4, 4],
-    [1, 5, 4],
-  ],
-  [
-    [4, 3, 5],
-    [1, 4, 5],
-    [5, 5, 5],
-  ],
-  [
-    [4, 0, 0],
-    [6, 3, 0],
-    [2, 1, 0],
-  ],
-  [
-    [2, 3, 1],
-    [6, 1, 1],
-    [7, 4, 1],
-  ],
-  [
-    [6, 3, 2],
-    [4, 1, 2],
-    [5, 4, 2],
-  ],
-  [
-    [1, 0, 3],
-    [3, 3, 3],
-    [7, 1, 3],
-  ],
-  [
-    [0, 3, 4],
-    [2, 1, 4],
-    [3, 4, 4],
-  ],
-  [
-    [4, 3, 5],
-    [0, 1, 5],
-    [1, 4, 5],
-  ],
-]
-
-vertex_buffer = []
-index_buffer = []
-index_lookup = {}
-
-for triangle in indices:
-    for p_ix, t_ix, n_ix in triangle:
-        key = (p_ix, n_ix, t_ix)
-        if key not in index_lookup:
-            position = positions[p_ix]
-            normal = normals[n_ix]
-            texture = textures[t_ix]
-            index = len(vertex_buffer)
-            index_lookup[key] = index
-            vertex_buffer.append((tuple(position),
-                                  tuple(normal),
-                                  tuple(texture)))
-
-        index_buffer.append(index_lookup[key])
-
-def gen():
-    for position, normal, texture in vertex_buffer:
-        p = ", ".join(map(str, map(float, position)))
-        n = ", ".join(map(str, map(float, normal)))
-        t = ", ".join(map(str, map(float, texture)))
-        print(f"vertex_t(vec3({p}), vec3({n}), vec2({t})),")
-
-    for i in range(len(index_buffer) // 3):
-        tri = ", ".join(str(index_buffer[i * 3 + n]) for n in range(3))
-        print(f"{tri},")
-
-from collections import defaultdict
-by_normal = defaultdict(list)
-for i in range(len(index_buffer) // 3):
-    tri = [index_buffer[i * 3 + n] for n in range(3)]
-    s = set(vertex_buffer[j][1] for j in tri)
-    assert len(s) == 1
-    normal, = iter(s)
-    by_normal[normal].append(tri)
-
-from pprint import pprint
-pprint(dict(by_normal))
-pprint(vertex_buffer)
diff --git a/minecraft/gen/data.py b/minecraft/gen/data.py
new file mode 100644
index 0000000..da4a05e
--- /dev/null
+++ b/minecraft/gen/data.py
@@ -0,0 +1,353 @@
+from dataclasses import dataclass
+
+class BlockID:
+    AIR = 0
+    STONE = 1
+    GRASS = 2
+    DIRT = 3
+    STONEBRICK = 4
+    WOOD = 5
+    SAPLING = 6
+    BEDROCK = 7
+    WATER = 8
+    WATER_CALM = 9
+    LAVA = 10
+    LAVA_CALM = 11
+    SAND = 12
+    GRAVEL = 13
+    ORE_GOLD = 14
+    ORE_IRON = 15
+    ORE_COAL = 16
+    TREE_TRUNK = 17
+    LEAVES = 18
+    SPONGE = 19
+    GLASS = 20
+    ORE_LAPIS = 21
+    BLOCK_LAPIS = 22
+    DISPENSER = 23
+    SANDSTONE = 24
+    NOTE_BLOCK = 25
+    BED = 26
+    RAIL_POWERED = 27
+    RAIL_ACTIVATOR = 28
+    PISTON_STICKY = 29
+    COBWEB = 30
+    TALL_GRASS = 31
+    DEAD_BUSH = 32
+    PISTON = 33
+    PISTON_HEAD = 34
+    CLOTH = 35
+    PISTON_MOVING = 36
+    FLOWER = 37
+    ROSE = 38
+    MUSHROOM_1 = 39
+    MUSHROOM_2 = 40
+    BLOCK_GOLD = 41
+    BLOCK_IRON = 42
+    STONESLAB_FULL = 43
+    STONESLAB_HALF = 44
+    BRICKS = 45
+    TNT = 46
+    BOOKSHELF = 47
+    MOSS_STONE = 48
+    OBSIDIAN = 49
+    TORCH = 50
+    FIRE = 51
+    SPAWNER = 52
+    STAIRS_WOOD = 53
+    CHEST = 54
+    WIRE = 55
+    ORE_EMERALD = 56
+    BLOCK_EMERALD = 57
+    WORKBENCH = 58
+    WHEAT = 59
+    FARMLAND = 60
+    FURNACE = 61
+    FURNACE_LIT = 62
+    SIGN = 63
+    DOOR_WOOD = 64
+    LADDER = 65
+    RAIL = 66
+    STAIRS_STONE = 67
+    SIGN_WALL = 68
+    LEVER = 69
+    PLATE_STONE = 70
+    DOOR_IRON = 71
+    PLATE_WOOD = 72
+    ORE_REDSTONE = 73
+    ORE_REDSTONE_LIT = 74
+    NOT_GATE_OFF = 75
+    NOT_GATE_ON = 76
+    BUTTON_STONE = 77
+    TOPSNOW = 78
+    ICE = 79
+    SNOW = 80
+    CACTUS = 81
+    CLAY = 82
+    REEDS = 83
+    JUKEBOX = 84
+    FENCE = 85
+    PUMPKIN = 86
+    NETHERRACK = 87
+    SOUL_SAND = 88
+    GLOWSTONE = 89
+    PORTAL = 90
+    PUMPKIN_LIT = 91
+    CAKE = 92
+    REPEATER_OFF = 93
+    REPEATER_ON = 94
+    INVISIBLE = 95
+    TRAPDOOR = 96
+    STONE_MONSTER_EGG = 97
+    STONE_BRICKS = 98
+    MUSHROOM1_BLOCK = 99
+    MUSHROOM2_BLOCK = 100
+    CLOTH_00 = 101
+    CLOTH_10 = 102
+    CLOTH_20 = 103
+    CLOTH_30 = 104
+    CLOTH_40 = 105
+    CLOTH_50 = 106
+    CLOTH_60 = 107
+    CLOTH_70 = 108
+    CLOTH_01 = 109
+    CLOTH_11 = 110
+    CLOTH_21 = 111
+    CLOTH_31 = 112
+    CLOTH_41 = 113
+    CLOTH_51 = 114
+    CLOTH_61 = 115
+
+    INFO_UPDATEGAME1 = 248
+    INFO_UPDATEGAME2 = 249
+    LEAVES_CARRIED = 254
+
+class Texture:
+    GRASS_TOP = 0
+    STONE = 1
+    DIRT = 2
+    GRASS_SIDE = 3
+    PLANKS = 4
+    STONE_SLAB_SIDE = 5
+    STONE_SLAB_TOP = 6
+    BRICKS = 7
+    TNT_SIDE = 8
+    TNT_TOP = 9
+    TNT_BOTTOM = 10
+    COBWEB = 11
+    ROSE = 12
+    FLOWER = 13
+    WATER_STATIC = 14
+    SAPLING = 15
+    STONEBRICK = 16
+    BEDROCK = 17
+    SAND = 18
+    GRAVEL = 19
+    LOG_SIDE = 20
+    LOG_TOP = 21
+    IRON = 22
+    GOLD = 23
+    EMERALD = 24
+    CHEST_ONE_TOP = 25
+    CHEST_ONE_SIDE = 26
+    CHEST_ONE_FRONT = 27
+    MUSHROOM_RED = 28
+    MUSHROOM_BROWN = 29
+    OBSIDIAN_CRYING = 30
+    FIRE1 = 31
+    ORE_GOLD = 32
+    ORE_IRON = 33
+    ORE_COAL = 34
+    BOOKSHELF = 35
+    MOSSY_STONE = 36
+    OBSIDIAN = 37
+    GRASS_SIDE_OVERLAY = 38
+    TALL_GRASS = 39
+    NONE40 = 40
+    CHEST_TWO_FRONT_LEFT = 41
+    CHEST_TWO_FRONT_RIGHT = 42
+    WORKBENCH_TOP = 43
+    FURNACE_FRONT = 44
+    FURNACE_SIDE = 45
+    DISPENSER_SIDE = 46
+    FIRE2 = 47
+    SPONGE = 48
+    GLASS = 49
+    ORE_EMERALD = 50
+    ORE_RED_STONE = 51
+    LEAVES_TRANSPARENT = 52
+    LEAVES_OPAQUE = 53
+    NONE54 = 54
+    DEAD_BUSH = 55
+    NONE56 = 56
+    CHEST_TWO_BACK_LEFT = 57
+    CHEST_TWO_BACK_RIGHT = 58
+    WORKBENCH_SIDE_1 = 59
+    WORKBENCH_SIDE_2 = 60
+    FURNACE_LIT = 61
+    FURNACE_TOP = 62
+    NONE63 = 63
+    CLOTH_64 = 64
+    SPAWNER = 65
+    SNOW = 66
+    ICE = 67
+    GRASS_SIDE_SNOW = 68
+    CACTUS_TOP = 69
+    CACTUS_SIDE = 70
+    CACTUS_BOTTOM = 71
+    CLAY = 72
+    REEDS = 73
+    JUKEBOX_SIDE = 74
+    JUKEBOX_TOP = 75
+    NONE76 = 76
+    NONE77 = 77
+    NONE78 = 78
+    NONE79 = 79
+    TORCH_LIT = 80
+    DOOR_TOP = 81
+    DOOR_IRON_TOP = 82
+    LADDER = 83
+    TRAPDOOR = 84
+    NONE85 = 85
+    FARMLAND = 86
+    FARMLAND_DRY = 87
+    WHEAT_0 = 88
+    WHEAT_1 = 89
+    WHEAT_2 = 90
+    WHEAT_3 = 91
+    WHEAT_4 = 92
+    WHEAT_5 = 93
+    WHEAT_6 = 94
+    WHEAT_7 = 95
+    LEVER = 96
+    DOOR_BOTTOM = 97
+    DOOR_IRON_BOTTOM = 98
+    TORCH_RED_STONE = 99
+    NONE100 = 100
+    NONE101 = 101
+    PUMPKIN_TOP = 102
+    BLOODSTONE = 103
+    SOULSAND = 104
+    GLOWSTONE = 105
+    STICKY_PISTON = 106
+    PISTON = 107
+    NONE108 = 108
+    NONE109 = 109
+    NONE110 = 110
+    NONE111 = 111
+    RAIL_CURVED = 112
+    CLOTH_112 = 113
+    CLOTH_113 = 114
+    TORCH_RED_STONE_OFF = 115
+    LOG_SPRUCE = 116
+    LOG_BIRCH = 117
+    PUMPKIN_SIDE = 118
+    PUMPKIN_FACE = 119
+    PUMPKIN_FACE_LIT = 120
+    CAKE_TOP = 121
+    CAKE_SIDE = 122
+    CAKE_SIDE_BIT = 123
+    CAKE_BOTTOM = 124
+    NONE125 = 125
+    NONE126 = 126
+    NONE127 = 127
+    RAIL = 128
+
+    LAPIS = 144
+    ORE_LAPIS = 160
+    POWERED_RAIL = 163
+    REDSTONE_DUST = 164
+
+    DETECTOR_RAIL = 195
+
+    SANDSTONE_TOP = 176
+    SANDSTONE_SIDE = 192
+    WATER = 205
+    SANDSTONE_BOTTOM = 208
+
+    LAVA = 237
+
+    INFO_UPDATEGAME1 = 252
+    INFO_UPDATEGAME2 = 253
+
+    LAVA_PLACEHOLDER = 255
+
+@dataclass
+class Tile:
+    block_id: BlockID
+    texture: Texture
+
+tiles = [
+    Tile(BlockID.STONE, Texture.STONE),
+    Tile(BlockID.GRASS, Texture.GRASS_TOP), # fixme
+    Tile(BlockID.DIRT, Texture.DIRT),
+    Tile(BlockID.STONEBRICK, Texture.STONEBRICK),
+    Tile(BlockID.WOOD, Texture.PLANKS),
+    Tile(BlockID.BEDROCK, Texture.BEDROCK),
+    Tile(BlockID.WATER, Texture.WATER), # fixme
+    Tile(BlockID.WATER_CALM, Texture.WATER), # fixme
+    Tile(BlockID.LAVA, Texture.LAVA), # fixme
+    Tile(BlockID.LAVA_CALM, Texture.LAVA), # fixme
+    Tile(BlockID.SAND, Texture.SAND),
+    Tile(BlockID.GRAVEL, Texture.GRAVEL),
+    Tile(BlockID.ORE_GOLD, Texture.ORE_GOLD),
+    Tile(BlockID.ORE_IRON, Texture.ORE_IRON),
+    Tile(BlockID.ORE_COAL, Texture.ORE_COAL),
+    Tile(BlockID.TREE_TRUNK, Texture.LOG_SIDE), # fixme
+    Tile(BlockID.LEAVES, Texture.LEAVES_TRANSPARENT), # fixme
+    Tile(BlockID.GLASS, Texture.GLASS),
+    Tile(BlockID.ORE_LAPIS, Texture.ORE_LAPIS),
+    Tile(BlockID.BLOCK_LAPIS, Texture.LAPIS),
+    Tile(BlockID.SANDSTONE, Texture.SANDSTONE_SIDE),
+    Tile(BlockID.FLOWER, Texture.FLOWER),
+    Tile(BlockID.ROSE, Texture.ROSE),
+    Tile(BlockID.MUSHROOM_1, Texture.MUSHROOM_BROWN),
+    Tile(BlockID.MUSHROOM_2, Texture.MUSHROOM_RED),
+    Tile(BlockID.BLOCK_GOLD, Texture.GOLD),
+    Tile(BlockID.BLOCK_IRON, Texture.IRON),
+    Tile(BlockID.STONESLAB_FULL, Texture.STONE_SLAB_SIDE), # fixme
+    Tile(BlockID.STONESLAB_HALF, Texture.STONE_SLAB_SIDE), # fixme
+    Tile(BlockID.BRICKS, Texture.BRICKS),
+    Tile(BlockID.TNT, Texture.TNT_SIDE),
+    Tile(BlockID.BOOKSHELF, Texture.BOOKSHELF),
+    Tile(BlockID.MOSS_STONE, Texture.MOSSY_STONE),
+    Tile(BlockID.OBSIDIAN, Texture.OBSIDIAN),
+    Tile(BlockID.TORCH, Texture.TORCH_LIT),
+    Tile(BlockID.STAIRS_WOOD, Texture.PLANKS), # fixme
+    Tile(BlockID.ORE_EMERALD, Texture.ORE_EMERALD),
+    Tile(BlockID.BLOCK_EMERALD, Texture.EMERALD),
+    Tile(BlockID.FARMLAND, Texture.FARMLAND), # fixme
+    Tile(BlockID.DOOR_WOOD, Texture.DOOR_TOP), # fixme
+    Tile(BlockID.LADDER, Texture.LADDER),
+    Tile(BlockID.STAIRS_STONE, Texture.STONEBRICK),
+    Tile(BlockID.DOOR_IRON, Texture.DOOR_IRON_TOP), # fixme
+    Tile(BlockID.ORE_REDSTONE, Texture.ORE_RED_STONE), # fixme
+    Tile(BlockID.ORE_REDSTONE_LIT, Texture.ORE_RED_STONE), # fixme
+    Tile(BlockID.TOPSNOW, Texture.SNOW),
+    Tile(BlockID.ICE, Texture.ICE),
+    Tile(BlockID.SNOW, Texture.SNOW),
+    Tile(BlockID.CACTUS, Texture.CACTUS_SIDE),
+    Tile(BlockID.CLAY, Texture.CLAY),
+    Tile(BlockID.REEDS, Texture.REEDS),
+    Tile(BlockID.FENCE, Texture.PLANKS),
+    Tile(BlockID.INVISIBLE, Texture.STONE),
+    Tile(BlockID.WOOD, Texture.PLANKS),
+    Tile(BlockID.LEAVES_CARRIED, Texture.LEAVES_TRANSPARENT), # fixme
+    Tile(BlockID.FIRE, Texture.FIRE1),
+    Tile(BlockID.SAPLING, Texture.SAPLING),
+    Tile(BlockID.SPONGE, Texture.SPONGE),
+    Tile(BlockID.TALL_GRASS, Texture.TALL_GRASS),
+    Tile(BlockID.DEAD_BUSH, Texture.DEAD_BUSH),
+    Tile(BlockID.PUMPKIN, Texture.PUMPKIN_FACE), # fixme
+    Tile(BlockID.PUMPKIN_LIT, Texture.PUMPKIN_FACE_LIT), # fixme
+    Tile(BlockID.NETHERRACK, Texture.BLOODSTONE),
+    Tile(BlockID.SOUL_SAND, Texture.SOULSAND),
+    Tile(BlockID.GLOWSTONE, Texture.GLOWSTONE),
+    Tile(BlockID.COBWEB, Texture.COBWEB),
+    Tile(BlockID.WORKBENCH, Texture.WORKBENCH_TOP), # fixme
+    Tile(BlockID.WHEAT, Texture.WHEAT_0),
+]
+
+tiles_by_id = {
+    tile.block_id: tile for tile in tiles
+}
diff --git a/minecraft/gen/mc.py b/minecraft/gen/mc.py
index ad7dcfd..0225e32 100644
--- a/minecraft/gen/mc.py
+++ b/minecraft/gen/mc.py
@@ -7,6 +7,7 @@ from collections import defaultdict
 import mcregion
 import vec3
 import vertex_buffer
+import data
 
 def wrap_n(nc, chunk_c):
     if nc < 0:
@@ -17,9 +18,15 @@ def wrap_n(nc, chunk_c):
         chunk_c = chunk_c + 1
     return nc, chunk_c
 
+non_solid_blocks = {
+    data.BlockID.TALL_GRASS,
+    data.BlockID.MUSHROOM_1,
+    data.BlockID.MUSHROOM_2,
+}
+
 def block_neighbors(level_table, chunk_x, chunk_z, block_index):
     block_id = level_table[(chunk_x, chunk_z)].blocks[block_index]
-    if block_id == 0:
+    if block_id == data.BlockID.AIR:
         return
 
     def neighbor_exists(nx, ny, nz):
@@ -36,7 +43,9 @@ def block_neighbors(level_table, chunk_x, chunk_z, block_index):
         if key not in level_table:
             return True
         n_block_id = level_table[key].blocks[n_block_index]
-        return n_block_id != 0
+
+        has_neighbor = (n_block_id != data.BlockID.AIR) and (n_block_id not in non_solid_blocks)
+        return has_neighbor
 
     x, y, z = mcregion.xyz_from_block_index(block_index)
 
@@ -49,7 +58,7 @@ def block_neighbors(level_table, chunk_x, chunk_z, block_index):
                 yield i
 
     normal_indices = list(find_non_neighbors())
-    if normal_indices:
+    if block_id in non_solid_blocks or normal_indices:
         yield center_position, block_id, normal_indices
 
 def devoxelize_region(level_table):
@@ -82,31 +91,61 @@ def build_block_configuration_table():
                 indices.extend(vertex_buffer.faces_by_normal[vertex_buffer.normals[j]])
         yield indices
 
+non_cube_blocks = {
+    data.BlockID.TALL_GRASS,
+}
+
+def pack_instance_data(position, block_id):
+    packed = struct.pack("<hhhBB",
+                         position[0], position[1], position[2],
+                         block_id,
+                         0)
+    return packed
+
 def build_block_instances(blocks):
     by_configuration = defaultdict(list)
 
+    deferred_blocks = []
+
     for position, block_id, normal_indices in blocks:
+        if block_id in non_cube_blocks:
+            deferred_blocks.append((position, block_id))
+            continue
         configuration = normal_indices_as_block_configuration(normal_indices)
-        #print(position, block_id, block_configuration)
         by_configuration[configuration].append((position, block_id))
 
     offset = 0
     configuration_instance_count_offset = []
     with open(f"{data_path}.instance.vtx", "wb") as f:
+        ######################################################################
+        # cubes
+        ######################################################################
         for configuration in range(64):
             if configuration not in by_configuration:
                 configuration_instance_count_offset.append((0, 0))
                 continue
-            blocks = by_configuration[configuration]
-            configuration_instance_count_offset.append((len(blocks), offset))
-            for position, block_id in blocks:
-                packed = struct.pack("<hhhBB",
-                                     position[0], position[1], position[2],
-                                     block_id,
-                                     0)
+            _blocks = by_configuration[configuration]
+            configuration_instance_count_offset.append((len(_blocks), offset))
+            for position, block_id in _blocks:
+                assert block_id not in non_cube_blocks, block_id
+                packed = pack_instance_data(position, block_id)
                 f.write(packed)
                 offset += len(packed)
 
+        ######################################################################
+        # non-cubes
+        ######################################################################
+        nc_offset = offset
+        nc_instance_count = 0
+        for position, block_id in deferred_blocks:
+            if block_id not in non_cube_blocks:
+                continue
+            packed = pack_instance_data(position, block_id)
+            f.write(packed)
+            offset += len(packed)
+            nc_instance_count += 1
+        configuration_instance_count_offset.append((nc_instance_count, nc_offset))
+
     with open(f"{data_path}.instance.cfg", "wb") as f:
         for instance_count, offset in configuration_instance_count_offset:
             print(instance_count, offset)
diff --git a/minecraft/gen/obj.py b/minecraft/gen/obj.py
new file mode 100644
index 0000000..64e5a2f
--- /dev/null
+++ b/minecraft/gen/obj.py
@@ -0,0 +1,80 @@
+from dataclasses import dataclass
+
+def ignore(state, line):
+    pass
+
+def normalize_float(s):
+    f = float(s)
+    if f == -0.0:
+        return 0.0
+    return f
+
+def parse_float_components(s, length):
+    components = s.split()
+    assert len(components) == length
+    return tuple(map(normalize_float, components))
+
+def parse_position(state, line):
+    position = parse_float_components(line, 3)
+    state.position.append(position)
+
+def parse_normal(state, line):
+    normal = parse_float_components(line, 3)
+    state.normal.append(normal)
+
+def parse_texture(state, line):
+    texture = parse_float_components(line, 2)
+    state.texture.append(texture)
+
+def parse_ptn(s):
+    ptn = tuple(int(i) - 1 for i in s.split("/"))
+    assert all(c >= 0 for c in ptn), ptn
+    assert len(ptn) == 3, ptn
+    return ptn
+
+def parse_triangle(state, line):
+    indices = line.split()
+    assert len(indices) == 3, line
+    triangle = tuple(map(parse_ptn, indices))
+    state.triangle.append(triangle)
+
+prefixes = [
+    ("#", ignore),
+    ("o ", ignore),
+    ("s ", ignore),
+    ("v ", parse_position),
+    ("vn ", parse_normal),
+    ("vt ", parse_texture),
+    ("f ", parse_triangle),
+]
+
+@dataclass
+class ObjState:
+    position: list
+    normal: list
+    texture: list
+    triangle: list
+
+    def __init__(self):
+        self.position = []
+        self.normal = []
+        self.texture = []
+        self.triangle = []
+
+def parse_obj(s):
+    state = ObjState()
+    lines = s.strip().split("\n")
+    for line in lines:
+        for prefix, func in prefixes:
+            if line.startswith(prefix):
+                line = line.removeprefix(prefix)
+                func(state, line)
+                break
+        else:
+            assert False, line
+    return state
+
+def parse_obj_from_filename(filename):
+    with open(filename, "r") as f:
+        buf = f.read()
+    return parse_obj(buf)
diff --git a/minecraft/gen/obj_state.py b/minecraft/gen/obj_state.py
new file mode 100644
index 0000000..8cdb164
--- /dev/null
+++ b/minecraft/gen/obj_state.py
@@ -0,0 +1,25 @@
+from collections import defaultdict
+import obj
+
+def append_triangles(state, vertex_buffer, index_buffer, index_lookup):
+    for triangle in state.triangle:
+        for p_ix, t_ix, n_ix in triangle:
+            key = (p_ix, n_ix, t_ix)
+            if key not in index_lookup:
+                position = state.position[p_ix]
+                normal = state.normal[n_ix]
+                texture = state.texture[t_ix]
+                index = len(vertex_buffer)
+                index_lookup[key] = index
+                vertex_buffer.append((position, normal, texture))
+            index_buffer.append(index_lookup[key])
+
+def build_faces_by_normal(vertex_buffer, index_buffer):
+    by_normal = defaultdict(list)
+    for i in range(len(index_buffer) // 3):
+        tri = [index_buffer[i * 3 + n] for n in range(3)]
+        s = set(vertex_buffer[j][1] for j in tri)
+        assert len(s) == 1, s
+        normal, = iter(s)
+        by_normal[normal].extend(tri)
+    return by_normal
diff --git a/minecraft/gen/tallgrass.obj b/minecraft/gen/tallgrass.obj
new file mode 100644
index 0000000..3f84163
--- /dev/null
+++ b/minecraft/gen/tallgrass.obj
@@ -0,0 +1,24 @@
+# Blender 5.0.0
+# www.blender.org
+o TallGrass
+v 0.800011 0.600021 0.800011
+v 0.800011 -1.000000 0.800011
+v -0.800010 -1.000000 0.800011
+v -0.800011 0.600021 0.800011
+v -0.800011 0.600021 -0.800011
+v -0.800011 -1.000000 -0.800011
+v 0.800011 -1.000000 -0.800011
+v 0.800010 0.600022 -0.800011
+vn 0.7071 -0.0000 0.7071
+vn 0.7071 -0.0000 -0.7071
+vt 1.000000 1.000000
+vt 0.000000 -0.000000
+vt 1.000000 0.000000
+vt 1.000000 1.000000
+vt -0.000000 1.000000
+vt 1.000000 0.000000
+s 0
+f 3/1/1 8/2/1 4/3/1
+f 5/2/2 2/4/2 6/5/2
+f 3/1/1 7/5/1 8/2/1
+f 5/2/2 1/6/2 2/4/2
diff --git a/minecraft/gen/vertex_buffer.py b/minecraft/gen/vertex_buffer.py
index 1f1b5cd..93a5d88 100644
--- a/minecraft/gen/vertex_buffer.py
+++ b/minecraft/gen/vertex_buffer.py
@@ -1,41 +1,8 @@
 import struct
 import vec3
-
-vertex_table = [
-    ((-1.0, 1.0, -1.0), (0.0, 1.0, 0.0), (1.0, 0.0)),
-    ((1.0, 1.0, 1.0), (0.0, 1.0, 0.0), (0.0, 1.0)),
-    ((1.0, 1.0, -1.0), (0.0, 1.0, 0.0), (0.0, 0.0)),
-    ((1.0, 1.0, 1.0), (0.0, 0.0, 1.0), (1.0, 1.0)),
-    ((-1.0, -1.0, 1.0), (0.0, 0.0, 1.0), (0.0, 0.0)),
-    ((1.0, -1.0, 1.0), (0.0, 0.0, 1.0), (1.0, 0.0)),
-    ((-1.0, 1.0, 1.0), (-1.0, 0.0, 0.0), (1.0, 1.0)),
-    ((-1.0, -1.0, -1.0), (-1.0, 0.0, 0.0), (0.0, 0.0)),
-    ((-1.0, -1.0, 1.0), (-1.0, 0.0, 0.0), (1.0, 0.0)),
-    ((1.0, -1.0, -1.0), (0.0, -1.0, 0.0), (1.0, 0.0)),
-    ((-1.0, -1.0, 1.0), (0.0, -1.0, 0.0), (0.0, 1.0)),
-    ((-1.0, -1.0, -1.0), (0.0, -1.0, 0.0), (0.0, 0.0)),
-    ((1.0, 1.0, -1.0), (1.0, 0.0, 0.0), (1.0, 1.0)),
-    ((1.0, -1.0, 1.0), (1.0, 0.0, 0.0), (0.0, 0.0)),
-    ((1.0, -1.0, -1.0), (1.0, 0.0, 0.0), (1.0, 0.0)),
-    ((-1.0, 1.0, -1.0), (0.0, 0.0, -1.0), (1.0, 1.0)),
-    ((1.0, -1.0, -1.0), (0.0, 0.0, -1.0), (0.0, 0.0)),
-    ((-1.0, -1.0, -1.0), (0.0, 0.0, -1.0), (1.0, 0.0)),
-    ((-1.0, 1.0, 1.0), (0.0, 1.0, 0.0), (1.0, 1.0)),
-    ((-1.0, 1.0, 1.0), (0.0, 0.0, 1.0), (0.0, 1.0)),
-    ((-1.0, 1.0, -1.0), (-1.0, 0.0, 0.0), (0.0, 1.0)),
-    ((1.0, -1.0, 1.0), (0.0, -1.0, 0.0), (1.0, 1.0)),
-    ((1.0, 1.0, 1.0), (1.0, 0.0, 0.0), (0.0, 1.0)),
-    ((1.0, 1.0, -1.0), (0.0, 0.0, -1.0), (0.0, 1.0))
-]
-
-faces_by_normal = {
-    (-1.0, 0.0, 0.0): [6, 7, 8, 6, 20, 7],
-    (0.0, -1.0, 0.0): [9, 10, 11, 9, 21, 10],
-    (0.0, 0.0, -1.0): [15, 16, 17, 15, 23, 16],
-    (0.0, 0.0, 1.0): [3, 4, 5, 3, 19, 4],
-    (0.0, 1.0, 0.0): [0, 1, 2, 0, 18, 1],
-    (1.0, 0.0, 0.0): [12, 13, 14, 12, 22, 13]
-}
+import obj
+import obj_state
+import sys
 
 normals = [
     (-1.0, 0.0, 0.0),
@@ -46,7 +13,9 @@ normals = [
     (1.0, 0.0, 0.0),
 ]
 
-def build_configuration_index_buffers(f):
+def build_configuration_index_buffers(f, faces_by_normal):
+    assert(set(normals) == set(faces_by_normal.keys()))
+
     offset = 0
     configuration_offsets = []
     for configuration in range(64):
@@ -65,14 +34,37 @@ def build_configuration_index_buffers(f):
         if i % 8 == 7:
             print()
 
-def build_vertex_buffer(f):
-    for position, normal, texture in vertex_table:
+def build_vertex_buffer(f, vertex_buffer):
+    for position, normal, texture in vertex_buffer:
         position = vec3.mul(position, 0.5)
         f.write(struct.pack("<eeeeeeee", *position, *normal, *texture))
 
-if __name__ == "__main__":
-    with open("configuration.idx", "wb") as f:
-        build_configuration_index_buffers(f)
+def write_indices(f, index_buffer, start, count):
+    for i in range(count):
+        f.write(struct.pack("<B", index_buffer[start + i]))
 
-    with open("per_vertex.vtx", "wb") as f:
-        build_vertex_buffer(f)
+def main():
+    vertex_buffer = []
+    index_buffer = []
+    index_lookup = {}
+
+    cube_state = obj.parse_obj_from_filename("cube.obj")
+
+    obj_state.append_triangles(cube_state, vertex_buffer, index_buffer, index_lookup)
+    cube_faces_by_normal = obj_state.build_faces_by_normal(vertex_buffer, index_buffer)
+
+    tallgrass_index_start = len(index_buffer)
+    tallgrass_state = obj.parse_obj_from_filename("tallgrass.obj")
+    obj_state.append_triangles(tallgrass_state, vertex_buffer, index_buffer, index_lookup)
+    tallgrass_index_count = len(index_buffer) - tallgrass_index_start
+    print(tallgrass_index_start, tallgrass_index_count)
+
+    with open("../configuration.idx", "wb") as f:
+        build_configuration_index_buffers(f, cube_faces_by_normal)
+        write_indices(f, index_buffer, tallgrass_index_start, tallgrass_index_count)
+
+    with open("../per_vertex.vtx", "wb") as f:
+        build_vertex_buffer(f, vertex_buffer)
+
+if __name__ == "__main__":
+    main()
diff --git a/minecraft/per_vertex.vtx b/minecraft/per_vertex.vtx
index 7d5055f..497b4a4 100644
Binary files a/minecraft/per_vertex.vtx and b/minecraft/per_vertex.vtx differ
diff --git a/minecraft/region.-1.-1.instance.cfg b/minecraft/region.-1.-1.instance.cfg
index 88236cf..c925ab2 100644
Binary files a/minecraft/region.-1.-1.instance.cfg and b/minecraft/region.-1.-1.instance.cfg differ
diff --git a/minecraft/region.-1.-1.instance.vtx b/minecraft/region.-1.-1.instance.vtx
index 2361482..eb04261 100644
Binary files a/minecraft/region.-1.-1.instance.vtx and b/minecraft/region.-1.-1.instance.vtx differ
diff --git a/minecraft/region.-1.0.instance.cfg b/minecraft/region.-1.0.instance.cfg
index e8c8062..bec1c85 100644
Binary files a/minecraft/region.-1.0.instance.cfg and b/minecraft/region.-1.0.instance.cfg differ
diff --git a/minecraft/region.-1.0.instance.vtx b/minecraft/region.-1.0.instance.vtx
index aa1c7b0..df8f91d 100644
Binary files a/minecraft/region.-1.0.instance.vtx and b/minecraft/region.-1.0.instance.vtx differ
diff --git a/minecraft/region.0.-1.instance.cfg b/minecraft/region.0.-1.instance.cfg
index 7853d47..599397e 100644
Binary files a/minecraft/region.0.-1.instance.cfg and b/minecraft/region.0.-1.instance.cfg differ
diff --git a/minecraft/region.0.-1.instance.vtx b/minecraft/region.0.-1.instance.vtx
index 38a011d..33e417b 100644
Binary files a/minecraft/region.0.-1.instance.vtx and b/minecraft/region.0.-1.instance.vtx differ
diff --git a/minecraft/region.0.0.instance.cfg b/minecraft/region.0.0.instance.cfg
index f22c74c..c82cbea 100644
Binary files a/minecraft/region.0.0.instance.cfg and b/minecraft/region.0.0.instance.cfg differ
diff --git a/minecraft/region.0.0.instance.vtx b/minecraft/region.0.0.instance.vtx
index d114963..319c4df 100644
Binary files a/minecraft/region.0.0.instance.vtx and b/minecraft/region.0.0.instance.vtx differ
diff --git a/shader/test.frag b/shader/test.frag
index 113cd5c..11dce84 100644
--- a/shader/test.frag
+++ b/shader/test.frag
@@ -12,7 +12,7 @@ uniform sampler2D TerrainSampler;
 
 int Textures[256] = int[256](
   185,   1,   0,   2,  16,   4,  15,  17, 205, 205, 237, 237,  18,  19,  32,  33,
-   34,  20,  52,  48,  49, 185, 185, 185, 185, 185, 185, 185, 185, 185, 185,   0,
+   34,  20,  52,  48,  49, 185, 185, 185, 185, 185, 185, 185, 185, 185, 185,  39,
   185, 185, 185,  64, 185,  13,  12,  29,  28,  39,  38,   5,   5,   7,   8,  35,
    36,  37,  80,  31,  65,   4,  27,  84,  50,  40,  43,  88,  87,  44,  61, 185,
    81,  83, 128,  16, 185,  96,   6,  82,   6,  51,  51, 115,  99, 185,  66,  67,
@@ -46,11 +46,13 @@ void main()
     return;
   }
 
-  if (int(fs_in.BlockID) == 18) // leaves
+  if (fs_in.BlockID == 18 || fs_in.BlockID == 31) // leaves
     texture_color.xyz *= vec3(0.125, 0.494, 0.027);
 
   if (diffuse_intensity < 0.1)
     diffuse_intensity = 0.1;
+  if (fs_in.BlockID == 31) // tall_grass
+    diffuse_intensity = 1.0;
 
   FragColor = vec4(texture_color.xyz * vec3(diffuse_intensity), 1.0);
 }
diff --git a/src/test.cpp b/src/test.cpp
index 3ebf138..f4e794f 100644
--- a/src/test.cpp
+++ b/src/test.cpp
@@ -34,7 +34,7 @@ struct char_tpl {
 };
 
 static const int region_count = 4;
-static const char_tpl vertex_paths[region_count] = {
+static const char_tpl vertex_paths[] = {
   { "minecraft/region.0.0.instance.vtx", "minecraft/region.0.0.instance.cfg" },
   { "minecraft/region.-1.0.instance.vtx", "minecraft/region.-1.0.instance.cfg" },
   { "minecraft/region.0.-1.instance.vtx", "minecraft/region.0.-1.instance.cfg" },
@@ -49,11 +49,13 @@ static unsigned int per_vertex_buffer;
 static const int vertex_size = 8;
 static const int per_vertex_size = (3 + 3 + 2) * 2;
 
+static const int instance_cfg_length = 64 + 1;
+
 struct instance_cfg {
-  struct {
+  struct region_instance {
     int instance_count;
     int offset;
-  } cfg[64];
+  } cfg[instance_cfg_length];
 };
 
 static instance_cfg instance_cfg[region_count];
@@ -160,7 +162,7 @@ void load_instance_cfg(int i)
 {
   int data_size;
   void * data = read_file(vertex_paths[i].cfg, &data_size);
-  assert(data_size == 512);
+  assert(data_size == (sizeof (struct instance_cfg)));
 
   memcpy(&instance_cfg[i], data, data_size);
 }
@@ -308,6 +310,9 @@ void draw()
   for (int region_index = 0; region_index < region_count; region_index++) {
     glBindVertexBuffer(1, per_instance_vertex_buffers[region_index], 0, vertex_size);
 
+    //////////////////////////////////////////////////////////////////////
+    // cube blocks
+    //////////////////////////////////////////////////////////////////////
     for (int configuration = 1; configuration < 64; configuration++) {
       int element_count = 6 * popcount(configuration);
       const void * indices = (void *)((ptrdiff_t)index_buffer_configuration_offsets[configuration]); // index into configuration.idx
@@ -320,5 +325,18 @@ void draw()
 
       glDrawElementsInstancedBaseInstance(GL_TRIANGLES, element_count, GL_UNSIGNED_BYTE, indices, instance_count, base_instance);
     }
+
+    //////////////////////////////////////////////////////////////////////
+    // non-cube blocks
+    //////////////////////////////////////////////////////////////////////
+    {
+      int element_count = 6 * 2;
+      const void * indices = (void *)((ptrdiff_t)1152);
+      int instance_count = instance_cfg[region_index].cfg[64].instance_count;
+      int base_instance = instance_cfg[region_index].cfg[64].offset / vertex_size; // index into region.0.0.instance.vtx
+      if (instance_count == 0)
+        continue;
+      glDrawElementsInstancedBaseInstance(GL_TRIANGLES, element_count, GL_UNSIGNED_BYTE, indices, instance_count, base_instance);
+    }
   }
 }