abdelrahman/tinyrenderer
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Move viewport matrix multiplication out of vertex shader

Browse Source
This commit is contained in:
Abdelrahman Said 2024-08-26 22:30:05 +01:00
parent 319bad9659
commit 97622d0bf7
4 changed files with 31 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
src/model/render.c
View File

@ -75,8 +75,7 @@ internal void render_triangle(const Triangle *triangle, const Model *model,
};
for (u64 i = 0; i < TRIANGLE_VERTICES; ++i) {
vertices[i] =
run_vertex_shader(shader, &vertices[i], (Buffer *)&render->img);
vertices[i] = run_vertex_shader(shader, &vertices[i]);
}
if (render_type == RENDER_TYPE_WIREFRAME) {
@ -102,11 +101,17 @@ internal void fill_triangle(Render *render, ShaderID shader,
const Model *model, RenderType type) {
Image *img = &(render->img);
Depth *depth = &(render->depth);
TriangleBBox bbox = get_triangle_bbox(img, vertices);
V3f vert0 = vertices[0];
V3f vert1 = vertices[1];
V3f vert2 = vertices[2];
V3f vp_verts[TRIANGLE_VERTICES] = {0};
for (u64 i = 0; i < TRIANGLE_VERTICES; ++i) {
vp_verts[i] = get_viewport_vertex(&vertices[i], img);
}
TriangleBBox bbox = get_triangle_bbox(img, vp_verts);
V3f vert0 = vp_verts[0];
V3f vert1 = vp_verts[1];
V3f vert2 = vp_verts[2];
V3f point;
V3f coords;
@ -140,12 +145,12 @@ internal void fill_triangle(Render *render, ShaderID shader,
continue;
}
px = vertices[0].x * coords.x + vertices[1].x * coords.y +
vertices[2].x * coords.z;
py = vertices[0].y * coords.x + vertices[1].y * coords.y +
vertices[2].y * coords.z;
pz = vertices[0].z * coords.x + vertices[1].z * coords.y +
vertices[2].z * coords.z;
px = vp_verts[0].x * coords.x + vp_verts[1].x * coords.y +
vp_verts[2].x * coords.z;
py = vp_verts[0].y * coords.x + vp_verts[1].y * coords.y +
vp_verts[2].y * coords.z;
pz = vp_verts[0].z * coords.x + vp_verts[1].z * coords.y +
vp_verts[2].z * coords.z;
position = (V3f){px, py, pz};
normalise_v3(position);
data.position = position;
@ -207,5 +212,10 @@ internal V3f get_barycentric_coords(V3f a, V3f b, V3f c, V3f p) {
internal V3f get_viewport_vertex(const V3f *vertex, const Image *img) {
V4f vh = {.x = vertex->x, .y = 0.0f - vertex->y, .z = vertex->z, .w = 1.0f};
vh = mat4x4_mul_vec4(viewport(vh.x, vh.y, img->width, img->height), vh);
return project_vec4(vh);
V3f output = project_vec4(vh);
output.x = clamp(output.x, 0.0f, img->width);
output.y = clamp(output.y, 0.0f, img->height);
return output;
}

8
src/shader/shader.c
View File

@ -28,10 +28,8 @@ ShaderID register_shader(void *shader, VertexShader *vertex,
return (ShaderID){g_repository.count};
}
V3f run_vertex_shader(ShaderID shader, const V3f *vertex,
const Buffer *out_buf) {
if (IS_INVALID_SHADER(shader) || shader.id > g_repository.count || !vertex ||
!out_buf) {
V3f run_vertex_shader(ShaderID shader, const V3f *vertex) {
if (IS_INVALID_SHADER(shader) || shader.id > g_repository.count || !vertex) {
return (V3f){0};
}
@ -42,7 +40,7 @@ V3f run_vertex_shader(ShaderID shader, const V3f *vertex,
return (V3f){0};
}
return vertex_func(shader_obj, vertex, out_buf);
return vertex_func(shader_obj, vertex);
}
FragmentResult run_fragment_shader(ShaderID shader, const FragmentData *data,

6
src/shader/shader.h
View File

@ -29,16 +29,14 @@ struct fragment_data {
#define DISCARDED_FRAGMENT ((FragmentResult){.discard = true})
#define DISCARD_FRAGMENT(RESULT) (RESULT.discard)
typedef V3f(VertexShader)(void *shader, const V3f *vertex,
const Buffer *out_buf);
typedef V3f(VertexShader)(void *shader, const V3f *vertex);
typedef FragmentResult(FragmentShader)(void *shader, const FragmentData *data,
const Colour *colour,
const Model *model);
ShaderID register_shader(void *shader, VertexShader *vertex,
FragmentShader *fragment);
V3f run_vertex_shader(ShaderID shader, const V3f *vertex,
const Buffer *out_buf);
V3f run_vertex_shader(ShaderID shader, const V3f *vertex);
FragmentResult run_fragment_shader(ShaderID shader, const FragmentData *data,
const Colour *colour, const Model *model);

15
src/shader/shaders.c
View File

@ -32,8 +32,7 @@ internal V3f g_target = {0};
internal V3f g_up = {0.0f, 1.0f, 0.0f};
internal M4x4f g_cam_matrix = mat4x4_identity;
internal V3f general_shader_vertex(void *shader, const V3f *vertex,
const Buffer *out_buf);
internal V3f general_shader_vertex(void *shader, const V3f *vertex);
internal FragmentResult phong_shader_fragment(void *shader,
const FragmentData *data,
const Colour *colour,
@ -66,22 +65,14 @@ void load_shaders(void) {
albedo_shader_fragment);
}
internal V3f general_shader_vertex(void *shader, const V3f *vertex,
const Buffer *out_buf) {
internal V3f general_shader_vertex(void *shader, const V3f *vertex) {
Shader *shader_ptr = (Shader *)shader;
V4f vh = {.x = vertex->x, .y = vertex->y, .z = vertex->z, .w = 1.0f};
vh = mat4x4_mul_vec4(shader_ptr->projection,
mat4x4_mul_vec4(shader_ptr->model_view, vh));
vh.y = 0.0 - vh.y;
vh = mat4x4_mul_vec4(viewport(vh.x, vh.y, out_buf->width, out_buf->height),
vh);
V3f output = project_vec4(vh);
output.x = clamp(output.x, 0.0f, out_buf->width);
output.y = clamp(output.y, 0.0f, out_buf->height);
return output;
return project_vec4(vh);
}
internal FragmentResult phong_shader_fragment(void *shader,