Add texture loading

7 files changed, 85 insertions, 56 deletions

diff --git a/src/core/src/loop.c b/src/core/src/loop.c
index 534acce..d083e6f 100644
--- a/src/core/src/loop.c
+++ b/src/core/src/loop.c
@@ -44,12 +44,6 @@ static Camera default_camera = {
 input_callback_t* callbacks[128];
 usize callbacks_len;
 
-/* TODO: MOVE ME */
-#include <glad/gl.h>
-char *img_filename = "test.png";
-unsigned char *test_image = NULL;
-GLuint img_texture;
-
 i32 nproc(void) {
   return get_nprocs();
 }
@@ -247,28 +241,6 @@ Platform* engine_init(const char* windowtitle, i32 windowWidth, i32 windowHeight
   p->cam = &default_camera;
   glm_ortho_default(45.f, p->cam->per);
 
-  {
-    int width;
-    int height;
-    int components_per_pixel;
-    test_image =
-        stbi_load(img_filename, &width, &height, &components_per_pixel, 0);
-    if (test_image == NULL) {
-      ERROR("Failed to load image %s", img_filename);
-    } else {
-      const GladGLContext* gl = w->context;
-      gl->GenTextures(1, &img_texture);
-      gl->BindTexture(GL_TEXTURE_2D, img_texture);
-
-      gl->TexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA,
-                     GL_UNSIGNED_BYTE, test_image);
-
-      gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-      gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-
-      stbi_image_free(test_image);
-    }
-  }
   // TODO: Add global bindings
 
   INFO("Available cores: %d", nproc());
diff --git a/src/rendering/include/engine/rendering/rendering.h b/src/rendering/include/engine/rendering/rendering.h
index 87de0b2..1412cb4 100644
--- a/src/rendering/include/engine/rendering/rendering.h
+++ b/src/rendering/include/engine/rendering/rendering.h
@@ -20,6 +20,7 @@ extern "C" {
 #define RGB(_r, _g, _b) RGBA(_r, _g, _b, 0xFF)
 
 /* Types */
+/* TODO: Cleanup these types. */
 typedef struct {
   u8 r;
   u8 g;
@@ -28,6 +29,14 @@ typedef struct {
 } Engine_color;
 
 typedef struct {
+  /* Maybe implement types, such as `atlas` (default), `standalone`, or
+   * something idk. */
+  u32 id;
+  i32 width;
+  i32 height;
+} Texture;
+
+typedef struct {
   u32 texture_id;
   v2_i32 coord;
 } Sprite;
@@ -145,6 +154,8 @@ u32 ComposeShader(u32 *shaders, usize shaders_len);
 
 ShaderType guess_shadertype_from_filename(const char *restrict fname);
 
+Texture createTextureFromImageData(unsigned char* image_data, i32 width, i32 height);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/rendering/src/rendering.c b/src/rendering/src/rendering.c
index aa9306e..d475ee2 100644
--- a/src/rendering/src/rendering.c
+++ b/src/rendering/src/rendering.c
@@ -252,3 +252,28 @@ Sprite sprite_new(u64 tid, u8 coord) {
         .y = ts * ((coord & 0xF0) >> 4),
       }};
 }
+
+Texture createTextureFromImageData(unsigned char* image_data, i32 width, i32 height) {
+  Window* restrict w = GLOBAL_PLATFORM->window;
+  Texture t;
+  t.width = width;
+  t.height = height;
+
+  if (w->renderer != WINDOW_RENDERER_OPENGL) {
+    ERROR("createTextureFromImageData not implemented for chosen renderer!");
+    return (Texture){.id = 0, .width = 0, .height = 0};
+  }
+
+  const GladGLContext* gl = w->context;
+
+  gl->GenTextures(1, &t.id);
+  gl->BindTexture(GL_TEXTURE_2D, t.id);
+
+  gl->TexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA,
+                 GL_UNSIGNED_BYTE, image_data);
+
+  gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+  gl->TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+  return t;
+}
diff --git a/src/resources/include/engine/resources.h b/src/resources/include/engine/resources.h
index fe78a7d..707bbde 100644
--- a/src/resources/include/engine/resources.h
+++ b/src/resources/include/engine/resources.h
@@ -65,8 +65,8 @@ typedef struct {
 typedef struct {
   enum Asset type;
   const char* path;
-  i32 width;
-  i32 height;
+  /* Bits per component, set to zero if you don't want to change the format. */
+  i32 bpc;
 } Asset_TextureSpec;
 
 typedef union {
@@ -90,21 +90,25 @@ typedef struct {
   /* Loaded assets */
   usize shader_len;
   Shader* shader;
+
+  usize texture_len;
+  Texture* texture;
 } Resources;
 
 #define TextureDefinition(_path, ...) unimplemented
 #define Resource_AudioDefinition(_path, ...) unimplemented
-#define Declare_Shader(_path) (const asset_t){.shader = {.type = Asset_shader, .path=_path}}
+#define Declare_Shader(PATH) (const asset_t){.shader = {.type = Asset_shader, .path=PATH}}
 #define Declare_ShaderProgram(SHADERS, NUMSHADERS) (const asset_t){.shaderprog = {.type = Asset_shaderprog, .shader=SHADERS, .shader_len=NUMSHADERS}}
+#define Declare_Texture(PATH) (const asset_t){.texture = {.type = Asset_texture, .path=PATH, .bpc=0}}
 
 void* get_asset(Resources* r, u32 idx);
 
 /* Each of resource_load_font, resource_load_texture, and resource_load_audio
  * loads a given resource into the engines memory and returns an identifier.
  */
-isize resource_load_font(Asset_FontSpec font_def);
-isize resource_load_texture(Asset_TextureSpec texture_def);
-isize resource_load_audio(Asset_AudioSpec audio_def);
+//isize resource_load_font(Asset_FontSpec font_def);
+//isize resource_load_texture(Asset_TextureSpec texture_def);
+//isize resource_load_audio(Asset_AudioSpec audio_def);
 
 // Loads all resources specified in `assets` and populates corresponding
 // resources members.
diff --git a/src/resources/include/engine/resources/texture.h b/src/resources/include/engine/resources/texture.h
index 979dd25..9f533d6 100644
--- a/src/resources/include/engine/resources/texture.h
+++ b/src/resources/include/engine/resources/texture.h
@@ -6,14 +6,10 @@ extern "C" {
 #endif
 
 #include <engine/core/types.h>
+#include <engine/resources.h>
+#include <engine/rendering/rendering.h>
 
-typedef struct {
-  const i32 tilesize;
-  const i32 width;
-  const i32 height;
-} Texture;
-
-Texture* load_texture(void* render, const Asset_TextureSpec* ts);
+Texture load_texture(const Asset_TextureSpec *restrict ts);
 
 #ifdef __cplusplus
 }
diff --git a/src/resources/src/resources.c b/src/resources/src/resources.c
index 99f6f99..a42a864 100644
--- a/src/resources/src/resources.c
+++ b/src/resources/src/resources.c
@@ -42,6 +42,7 @@ i32 resources_load(Resources *resources) {
 
   isize i = 0;
 
+  // Count each type of resource so we can allocate appropriate sizes.
   for (i = 0; i < resources->assets_len; i++) {
     isize idx = 0;
 
@@ -50,7 +51,7 @@ i32 resources_load(Resources *resources) {
       case Asset_font:       idx = font_len++;       WARN("Font resource type not implemented!"); break;
       case Asset_shader:     idx = shader_len++;     break;
       case Asset_shaderprog: idx = shaderprog_len++; break;
-      case Asset_texture:    idx = texture_len++;    WARN("Texture resource type not implemented!");break;
+      case Asset_texture:    idx = texture_len++;    break;
 
       case Asset_error:
       default:
@@ -59,13 +60,14 @@ i32 resources_load(Resources *resources) {
         break;
     }
 
+    // Update index translation table.
     resources->get[i] = idx;
   }
 
   //resources->audio = calloc(audio_len, sizeof());
   //resources->font = calloc(font_len, sizeof());
   resources->shader = calloc(shaderprog_len, sizeof(Shader));
-  //resources->texture = calloc(texture_len, sizeof());
+  resources->texture = calloc(texture_len, sizeof(Texture));
 
   Shader* imm_shader = calloc(shader_len, sizeof(Shader));
 
@@ -110,8 +112,8 @@ i32 resources_load(Resources *resources) {
         resources->shader[resources->shader_len++] = s;
     } break;
     case Asset_texture:
-        texture_len++;
-        WARN("Texture resource type not implemented!");
+        resources->texture[resources->texture_len++] = load_texture(&resources->assets[i].texture);
+        resources->texture_len++;
         break;
 
     case Asset_error:
diff --git a/src/resources/src/textures.c b/src/resources/src/textures.c
index cde56b7..7c205ef 100644
--- a/src/resources/src/textures.c
+++ b/src/resources/src/textures.c
@@ -1,22 +1,41 @@
 #include <engine/core/logging.h>
 #include <engine/resources.h>
+#include <stb/stb_image.h>
 
-// Use the engine/render.h backend to create a renderer-specific texture
-
-Texture* load_texture(void* render, const Asset_TextureSpec* ts) {
-  Texture* t = NULL;
+/* Uses stb_image to load an image, and passes it to the renderer for
+ * backend-specific texture creation. */
+Texture load_texture(const Asset_TextureSpec *restrict ts) {
+  int width;
+  int height;
+  int components_per_pixel;
+  unsigned char* img;
+  Texture t;
+  const Texture err = (Texture){.id = 0, .width = 0, .height = 0};
 
   if (ts == NULL) {
     ERROR("Invalid Asset_TextureSpec\n");
-    return NULL;
+    return err;
+  }
+
+  if (ts->path == NULL) {
+    ERROR("Missing path in Asset_TextureSpec\n");
+    return err;
   }
 
-  //t = (Texture*)malloc(sizeof(Texture));
-  //t->texture = new_texture;
-  ///* Assigning const value */
-  //*(i32*)&t->tilesize = tw;
-  //*(i32*)&t->width = ts->width;
-  //*(i32*)&t->height = ts->height;
+  img = stbi_load(ts->path, &width, &height, &components_per_pixel, 0);
+
+  if (img == NULL) {
+    ERROR("Failed to load image %s", ts->path);
+    return err;
+  } else {
+    t = createTextureFromImageData(img, width, height);
+    stbi_image_free(img);
+  }
+
+  if (t.id == 0) {
+    ERROR("Failed to create texture %s!", ts->path);
+    return err;
+  }
 
   return t;
 }