include/rasteriser/rasteriser.h

@@ -18,7 +18,6 @@ typedef struct {
 MAKE_LIST_TYPE(f32);
 MAKE_LIST_TYPE(vec2i_t);
 MAKE_LIST_TYPE(vec3f_t);
-MAKE_LIST_TYPE(vec4f_t);
 MAKE_LIST_TYPE(scene_triangle_t);
 
 typedef struct {
@@ -52,21 +51,11 @@ typedef struct {
   transform_t transform;
 } instance_t;
 
-typedef struct {
-  vec3f_t normal;
-  f32 distance;
-} clipping_plane_t;
-
 typedef struct {
   u64 instance_count;
   instance_t *instances;
   camera_t *camera;
   const mat3x4f_t *proj_matrix;
-  clipping_plane_t near;
-  clipping_plane_t left;
-  clipping_plane_t right;
-  clipping_plane_t bottom;
-  clipping_plane_t top;
 } rasteriser_scene_t;
 
 void render_scene(window_t *wnd, Arena *arena, const rasteriser_scene_t *scene);

include/vector/vec.h

@@ -128,7 +128,6 @@ mat4x4f_t get_scaling_matrix(vec3f_t scale);
 mat3x3f_t get_rotation_mat3x3f(vec3f_t rotation);
 vec3f_t mul_mat3x4f_by_vec4f(mat3x4f_t mat, vec4f_t vec);
 mat3x4f_t mul_mat3x4f_by_mat4x4f(mat3x4f_t mat1, mat4x4f_t mat2);
-vec4f_t mul_mat4x4f_by_vec4f(mat4x4f_t mat, vec4f_t vec);
 mat4x4f_t mul_mat4x4f(mat4x4f_t mat1, mat4x4f_t mat2);
 
 #endif // !VEC_H

src/rasteriser/main.c

@@ -8,7 +8,6 @@
 #include "window/window.h"
 #include <SDL2/SDL_events.h>
 #include <SDL2/SDL_keycode.h>
-#include <math.h>
 #include <stdlib.h>
 
 int main(void) {
@@ -98,40 +97,11 @@ int main(void) {
       (vec4f_t){0.0f, 0.0f, 1.0f, 0.0f},
   };
 
-  f32 sqrt_2 = sqrtf(2.0f);
-  f32 one_div_sqrt_2 = 1.0f / sqrt_2;
-  f32 neg_one_div_sqrt_2 = -1.0f / sqrt_2;
-
   rasteriser_scene_t scene = {
       .instance_count = ARR_LEN(instances),
       .instances = instances,
       .camera = &camera,
       .proj_matrix = &proj_matrix,
-      .near =
-          (clipping_plane_t){
-              .normal = (vec3f_t){0.0f, 0.0f, 1.0f},
-              .distance = viewport.z,
-          },
-      .left =
-          (clipping_plane_t){
-              .normal = (vec3f_t){one_div_sqrt_2, 0.0f, one_div_sqrt_2},
-              .distance = 0.0f,
-          },
-      .right =
-          (clipping_plane_t){
-              .normal = (vec3f_t){neg_one_div_sqrt_2, 0.0f, one_div_sqrt_2},
-              .distance = 0.0f,
-          },
-      .bottom =
-          (clipping_plane_t){
-              .normal = (vec3f_t){0.0f, one_div_sqrt_2, one_div_sqrt_2},
-              .distance = 0.0f,
-          },
-      .top =
-          (clipping_plane_t){
-              .normal = (vec3f_t){0.0f, neg_one_div_sqrt_2, one_div_sqrt_2},
-              .distance = 0.0f,
-          },
   };
 
   bool running = true;
@@ -171,7 +141,7 @@ int main(void) {
 
     clear_window(&window, bg);
 
-    render_scene(&window, frame_arena, &scene);
+    render_scene(&window, arena, &scene);
 
     swap_buffers(&window);
 

src/rasteriser/rasteriser.c

@@ -31,9 +31,9 @@ void render_scene(window_t *wnd, Arena *arena,
 
 void render_instance(window_t *wnd, Arena *arena, mat4x4f_t camera_matrix,
                      mat3x4f_t projection_matrix, const instance_t *instance) {
-  list_vec4f_t *transformed = list_create_with_capacity(
+  list_vec2i_t *projected = list_create_with_capacity(
-      vec4f_t, arena, instance->model->vertices->count * sizeof(vec4f_t));
+      vec2i_t, arena, instance->model->vertices->count * sizeof(vec3f_t));
-  if (!transformed) {
+  if (!projected) {
     return;
   }
 
@@ -47,25 +47,14 @@ void render_instance(window_t *wnd, Arena *arena, mat4x4f_t camera_matrix,
 
   mat4x4f_t xf_cam_mat = mul_mat4x4f(camera_matrix, trs_mat);
 
+  mat3x4f_t xf_proj_mat = mul_mat3x4f_by_mat4x4f(projection_matrix, xf_cam_mat);
+
   vec3f_t vertex = {0};
-  vec4f_t xf_vertex = {0};
+  vec2i_t point = {0};
   for (u64 i = 0; i < instance->model->vertices->count; ++i) {
     vertex = list_get(instance->model->vertices, i);
-    xf_vertex = mul_mat4x4f_by_vec4f(
+    vertex = mul_mat3x4f_by_vec4f(
-        xf_cam_mat, (vec4f_t){vertex.x, vertex.y, vertex.z, 1.0f});
+        xf_proj_mat, (vec4f_t){vertex.x, vertex.y, vertex.z, 1.0f});
-    list_append(vec4f_t, arena, transformed, xf_vertex);
-  }
-
-  list_vec2i_t *projected = list_create_with_capacity(
-      vec2i_t, arena, instance->model->vertices->count * sizeof(vec2i_t));
-  if (!projected) {
-    return;
-  }
-
-  vec2i_t point = {0};
-  for (u64 i = 0; i < transformed->count; ++i) {
-    xf_vertex = list_get(transformed, i);
-    vertex = mul_mat3x4f_by_vec4f(projection_matrix, xf_vertex);
     point = (vec2i_t){(i32)(vertex.x / vertex.z), (i32)(vertex.y / vertex.z)};
     list_append(vec2i_t, arena, projected, point);
   }

src/vector/vec.c

@@ -342,19 +342,6 @@ mat3x4f_t mul_mat3x4f_by_mat4x4f(mat3x4f_t mat1, mat4x4f_t mat2) {
   };
 }
 
-vec4f_t mul_mat4x4f_by_vec4f(mat4x4f_t mat, vec4f_t vec) {
-  f32 x = mat.row0.x * vec.x + mat.row0.y * vec.y + mat.row0.z * vec.z +
-          mat.row0.w * vec.w;
-  f32 y = mat.row1.x * vec.x + mat.row1.y * vec.y + mat.row1.z * vec.z +
-          mat.row1.w * vec.w;
-  f32 z = mat.row2.x * vec.x + mat.row2.y * vec.y + mat.row2.z * vec.z +
-          mat.row2.w * vec.w;
-  f32 w = mat.row3.x * vec.x + mat.row3.y * vec.y + mat.row3.z * vec.z +
-          mat.row3.w * vec.w;
-
-  return (vec4f_t){x, y, z, w};
-}
-
 mat4x4f_t mul_mat4x4f(mat4x4f_t mat1, mat4x4f_t mat2) {
   f32 row0_col0 = mat1.row0.x * mat2.row0.x + mat1.row0.y * mat2.row1.x +
                   mat1.row0.z * mat2.row2.x + mat1.row0.w * mat2.row3.x;