From 6d6d4781ff9d9049c346319bcb22fac9475c3a40 Mon Sep 17 00:00:00 2001
From: Abdelrahman <said.abdelrahman89@gmail.com>
Date: Sun, 18 Aug 2024 01:53:49 +0100
Subject: [PATCH] Extract shader into its own header

---
 src/main.c   |  7 +++----
 src/obj.c    |  2 +-
 src/obj.h    | 14 +-------------
 src/shader.h | 19 +++++++++++++++++++
 4 files changed, 24 insertions(+), 18 deletions(-)
 create mode 100644 src/shader.h

diff --git a/src/main.c b/src/main.c
index 1696294..1d2fe9d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -26,7 +26,7 @@ enum {
 
 internal M4x4f get_projection_matrix(ProjectionType projection_type);
 internal V3f main_shader_vertex(const V3f *vertex, M4x4f *model_view,
-                                M4x4f *projection, const Render *render);
+                                M4x4f *projection, const Image *img);
 
 int main(void) {
   Arena *arena = NULL;
@@ -82,12 +82,11 @@ internal M4x4f get_projection_matrix(ProjectionType projection_type) {
 }
 
 internal V3f main_shader_vertex(const V3f *vertex, M4x4f *model_view,
-                                M4x4f *projection, const Render *render) {
+                                M4x4f *projection, const Image *img) {
   V4f vh = {.x = vertex->x, .y = vertex->y, .z = vertex->z, .w = 1.0f};
   vh = mat4x4_mul_vec4((*projection), mat4x4_mul_vec4((*model_view), vh));
   vh.y = 0.0 - vh.y;
-  vh = mat4x4_mul_vec4(
-      viewport(vh.x, vh.y, render->img.width, render->img.height), vh);
+  vh = mat4x4_mul_vec4(viewport(vh.x, vh.y, img->width, img->height), vh);
 
   return project_vec4(vh);
 }
diff --git a/src/obj.c b/src/obj.c
index 0094a9e..d408f39 100644
--- a/src/obj.c
+++ b/src/obj.c
@@ -162,7 +162,7 @@ internal void render_triangle(const Triangle *triangle, const Model *model,
 
   for (u64 i = 0; i < TRIANGLE_VERTICES; ++i) {
     vertices[i] = shader->vertex(&vertices[i], shader->model_view,
-                                 shader->projection, render);
+                                 shader->projection, &render->img);
   }
 
   if (render_type == RENDER_TYPE_WIREFRAME) {
diff --git a/src/obj.h b/src/obj.h
index 03ee5a0..7ac49bf 100644
--- a/src/obj.h
+++ b/src/obj.h
@@ -4,8 +4,8 @@
 #include "aliases.h"
 #include "img.h"
 #include "mem_arena.h"
+#include "shader.h"
 #include "typed_list.h"
-#include "vec.h"
 
 #define INVALID_MODEL ((Model){0})
 #define IS_INVALID_MODEL(m) (m.vertices == NULL || m.triangles == NULL)
@@ -55,18 +55,6 @@ struct render {
   Depth depth;
 };
 
-typedef V3f(VertexShader)(const V3f *vertex, M4x4f *model_view,
-                          M4x4f *projection, const Render *render);
-typedef bool(FragmentShader)(Colour colour);
-
-typedef struct shader Shader;
-struct shader {
-  VertexShader *vertex;
-  FragmentShader *fragment;
-  M4x4f *model_view;
-  M4x4f *projection;
-};
-
 Model load_obj_file(Arena *arena, const char *filename, const char *texture);
 bool init_render(Arena *arena, Render *render, u64 width, u64 height);
 void render_model(const Model *model, Render *render, const Shader *shader,
diff --git a/src/shader.h b/src/shader.h
new file mode 100644
index 0000000..42817d8
--- /dev/null
+++ b/src/shader.h
@@ -0,0 +1,19 @@
+#ifndef SHADER_H
+#define SHADER_H
+
+#include "img.h"
+#include "vec.h"
+
+typedef V3f(VertexShader)(const V3f *vertex, M4x4f *model_view,
+                          M4x4f *projection, const Image *img);
+typedef bool(FragmentShader)(Colour colour);
+
+typedef struct shader Shader;
+struct shader {
+  VertexShader *vertex;
+  FragmentShader *fragment;
+  M4x4f *model_view;
+  M4x4f *projection;
+};
+
+#endif // SHADER_H