example/viewing_system: add "viewer" concept

example/viewing_system.cpp

@@ -19,6 +19,7 @@
 
 #include "geometry/geometry.hpp"
 #include "geometry/suzanne2.hpp"
+#include "geometry/plane2.hpp"
 
 #include "viewing_system/view_space.hpp"
 #include "viewing_system/screen_space.hpp"
@@ -28,17 +29,15 @@ uint32_t _ta_parameter_buf[((32 * 8192) + 32) / 4];
 struct viewer {
   vec3 position;
   vec3 orientation;
+  float azimuth;
+  float colatitude;
 };
 
-constexpr mat4x4 world_transform = { 1.f, 0.f, 0.f, 0.f,
-                                     0.f, 1.f, 0.f, 0.f,
-                                     0.f, 0.f, 1.f, 3.f,
-                                     0.f, 0.f, 0.f, 1.f };
-
 void ta_upload(ta_parameter_writer& parameter,
                const position__color * vertices,
                const face_vtn * faces,
                const uint32_t num_faces,
+	       const mat4x4 world_transform,
                const mat4x4 screen_transform
                )
 {
@@ -80,7 +79,7 @@ void ta_upload(ta_parameter_writer& parameter,
       vec4 v = transform * vertex;
 
       float x = v.x / v.w;
-      float y = v.y / v.w;
+      float y = -v.y / v.w;
       float z = v.w / v.z;
 
       x = x * 240.f + 320.f;
@@ -145,21 +144,24 @@ void main()
   core_init();
   init_texture_memory(opb_size);
 
+  float delta = 0;
+
+  uint32_t frame_ix = 0;
+  constexpr uint32_t num_frames = 1;
+
+  while (true) {
+
     viewer viewer {
-    .position    = {0.f, -3.f, 0.f},
+      .position    = {0.f, -1.f, -2.f},
       .orientation = {0.f, -1.f,  0.f}, // approximate "up" orientation
+      .azimuth     = 0,
+      .colatitude  = pi / 4.f * sin(delta) * 0.9f,
     };
 
-  vec3 plane_normal = view_space::viewing_direction(pi / 2.f, // azimuth
+    const vec3 plane_normal = view_space::viewing_direction(viewer.azimuth, viewer.colatitude);
-                                                    pi / 4.f  // colatitude
+    const vec3 up_vector = view_space::project_vector_to_plane(plane_normal, viewer.orientation);
-                                                    );
-  vec3 up_vector = view_space::project_vector_to_plane(plane_normal,
-                                                       viewer.orientation
-                                                       );
 
-  const mat4x4 view_space_transform = view_space::transformation_matrix(viewer.position,
+    const mat4x4 view_space_transform = view_space::transformation_matrix(viewer.position, plane_normal, up_vector);
-                                                                        plane_normal,
-                                                                        up_vector);
 
     const mat4x4 perspective_transform = screen_space::transformation_matrix(1.f,   // the z-coordinate of the view window
 									     100.f, // the z-coordinate of the far clip plane
@@ -169,22 +171,40 @@ void main()
     const mat4x4 screen_transform = perspective_transform * view_space_transform;
 
 
-  uint32_t frame_ix = 0;
-  constexpr uint32_t num_frames = 1;
-
-  while (true) {
     ta_polygon_converter_init(opb_size.total(),
 			      ta_alloc,
 			      640 / 32,
 			      480 / 32);
     auto parameter = ta_parameter_writer(ta_parameter_buf);
 
+
+    {
+      constexpr mat4x4 world_transform = { 1.f, 0.f, 0.f, 0.f,
+					   0.f, 1.f, 0.f, 0.f,
+					   0.f, 0.f, 1.f, 3.f,
+					   0.f, 0.f, 0.f, 1.f };
       ta_upload(parameter,
 		suzanne::vertices,
 		suzanne::faces,
 		suzanne::num_faces,
+		world_transform,
 		screen_transform
 		);
+    }
+
+    {
+      constexpr mat4x4 world_transform = { 0.1f, 0.f,  0.f,  0.f,
+					   0.f,  0.1f, 0.f,  1.2f,
+					   0.f,  0.f,  0.1f, 3.f,
+					   0.f,  0.f,  0.f,  1.f };
+      ta_upload(parameter,
+		plane::vertices,
+		plane::faces,
+		plane::num_faces,
+		world_transform,
+		screen_transform
+		);
+    }
 
     // end of opaque list
     parameter.append<ta_global_parameter::end_of_list>() = ta_global_parameter::end_of_list(para_control::para_type::end_of_list);
@@ -194,9 +214,10 @@ void main()
 
     core_start_render(frame_ix, num_frames);
 
-    v_sync_in();
+    v_sync_out();
     core_wait_end_of_render_video(frame_ix, num_frames);
 
     frame_ix += 1;
+    delta += pi * 2 / 360;
   }
 }

geometry/plane2.hpp

@@ -0,0 +1,31 @@
+#pragma once
+
+#include "geometry.hpp"
+
+namespace plane {
+  constexpr position__color vertices[] = {
+    { {-10.000000f,  0.000000f, -10.000000f}, { 0.011800f,  1.000000f,  1.000000f} },
+    { {10.000000f,  0.000000f, -10.000000f}, { 1.000000f,  0.003900f,  0.066700f} },
+    { {-10.000000f,  0.000000f, 10.000000f}, { 0.019600f,  1.000000f,  0.019600f} },
+    { {10.000000f,  0.000000f, 10.000000f}, { 1.000000f,  0.952900f,  0.011800f} },
+  };
+
+  constexpr vec2 texture[] = {
+    {  1.000000f,  0.000000f },
+    {  0.000000f,  1.000000f },
+    {  0.000000f,  0.000000f },
+    {  1.000000f,  1.000000f },
+  };
+
+  constexpr vec3 normals[] = {
+    { -0.000000f, -1.000000f, -0.000000f },
+  };
+
+  constexpr face_vtn faces[] = {
+    {{1, 0, 0}, {2, 1, 0}, {0, 2, 0}},
+    {{1, 0, 0}, {3, 3, 0}, {2, 1, 0}},
+  };
+
+  constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face_vtn));
+
+}

geometry/plane2.obj

@@ -0,0 +1,15 @@
+# Blender 3.3.6
+# www.blender.org
+o Plane
+v -10.000000 0.000000 -10.000000 0.0118 1.0000 1.0000
+v 10.000000 0.000000 -10.000000 1.0000 0.0039 0.0667
+v -10.000000 0.000000 10.000000 0.0196 1.0000 0.0196
+v 10.000000 0.000000 10.000000 1.0000 0.9529 0.0118
+vn -0.0000 -1.0000 -0.0000
+vt 0.000000 0.000000
+vt 1.000000 0.000000
+vt 0.000000 1.000000
+vt 1.000000 1.000000
+s 0
+f 2/2/1 3/3/1 1/1/1
+f 2/2/1 4/4/1 3/3/1