Moved all the mesh stuff to another file (introduced memory leak)

src/main.c

@@ -5,9 +5,8 @@
 
 #include "SDL3/SDL_events.h"
 #include "SDL3/SDL_keycode.h"
-#include "SDL3/SDL_surface.h"
-#include "SDL3_image/SDL_image.h"
 #include "camera.h"
+#include "mesh.h"
 #include "shader.h"
 #include "window.h"
 
@@ -77,87 +76,7 @@ int main(int argc, char *argv[]) {
     return EXIT_FAILURE;
   }
 
-  // set up vertex data (and buffer(s)) and configure vertex attributes
+  wn_mesh *mesh = wn_mesh_init(global_arena, shader);
-  float vertices[] = {
-      0.5f,  0.5f,  0.0f, 1.0f, 1.0f, // top right
-      0.5f,  -0.5f, 0.0f, 1.0f, 0.0f, // bottom right
-      -0.5f, -0.5f, 0.0f, 0.0f, 0.0f, // bottom left
-      -0.5f, 0.5f,  0.0f, 0.0f, 1.0f  // top left
-  };
-  unsigned int indices[] = {
-      0, 1, 3, // first Triangle
-      1, 2, 3  // second Triangle
-  };
-
-  GLuint VBO, VAO, EBO;
-  glGenVertexArrays(1, &VAO);
-  glGenBuffers(1, &VBO);
-  glGenBuffers(1, &EBO);
-  // bind the Vertex Array Object first, then bind and set vertex buffer(s), and
-  // then configure vertex attributes(s).
-  glBindVertexArray(VAO);
-
-  glBindBuffer(GL_ARRAY_BUFFER, VBO);
-  glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
-
-  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
-  glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices,
-               GL_STATIC_DRAW);
-
-  glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void *)0);
-  glEnableVertexAttribArray(0);
-  glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float),
-                        (void *)(3 * sizeof(float)));
-  glEnableVertexAttribArray(1);
-
-  // note that this is allowed, the call to glVertexAttribPointer registered VBO
-  // as the vertex attribute's bound vertex buffer object so afterwards we can
-  // safely unbind
-  // glBindBuffer(GL_ARRAY_BUFFER, 0);
-
-  // remember: do NOT unbind the EBO while a VAO is active as the bound element
-  // buffer object IS stored in the VAO; keep the EBO bound.
-  // glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
-
-  // You can unbind the VAO afterwards so other VAO calls won't accidentally
-  // modify this VAO, but this rarely happens. Modifying other VAOs requires a
-  // call to glBindVertexArray anyways so we generally don't unbind VAOs (nor
-  // VBOs) when it's not directly necessary.
-  // glBindVertexArray(0);
-
-  // Texture Load
-  SDL_Surface *image = IMG_Load("./data/testxure.png");
-  if (image == NULL) {
-    SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load texture");
-    return EXIT_FAILURE;
-  }
-  SDL_FlipSurface(image, SDL_FLIP_VERTICAL);
-
-  GLuint texture;
-  glActiveTexture(GL_TEXTURE0);
-  glGenTextures(1, &texture);
-
-  // Handle different SDL Surface data types
-  int mode = GL_RGBA;
-  //  if (image->format->BytesPerPixel == 4) {
-  //    mode = GL_RGBA;
-  //  }
-
-  glBindTexture(GL_TEXTURE_2D, texture);
-  // set the texture wrapping parameters
-  glTexParameteri(
-      GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
-      GL_REPEAT); // set texture wrapping to GL_REPEAT (default wrapping method)
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-  // set texture filtering parameters
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-
-  glTexImage2D(GL_TEXTURE_2D, 0, mode, image->w, image->h, 0, mode,
-               GL_UNSIGNED_BYTE, image->pixels);
-
-  glGenerateMipmap(GL_TEXTURE_2D);
-  SDL_DestroySurface(image);
 
   // Initialise camera
   Camera camera = Camera_default;
@@ -196,24 +115,11 @@ int main(int argc, char *argv[]) {
     glClearColor(0.1f, 0.3f, 0.4f, 1.f);
     glClear(GL_COLOR_BUFFER_BIT);
 
-    // draw our first triangle
+    wn_mesh_draw(mesh);
-    glUseProgram(shader->shaderProgram);
-
-    // seeing as we only have a single VAO there's no need to bind it
-    // every time, but we'll do so to keep things a bit more organized
-    glBindVertexArray(VAO);
-
-    // glDrawArrays(GL_TRIANGLES, 0, 6);
-    glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
-    // glBindVertexArray(0); // no need to unbind it every time
 
     wn_swapwindow(window);
   }
 
-  glDeleteVertexArrays(1, &VAO);
-  glDeleteBuffers(1, &VBO);
-  glDeleteBuffers(1, &EBO);
-
   arena_deinit(global_arena);
   return EXIT_SUCCESS;
 }

src/mesh.c

@@ -0,0 +1,117 @@
+#include <GL/glew.h>
+
+#include "SDL3/SDL_surface.h"
+#include "SDL3_image/SDL_image.h"
+#include "arena_allocator.h"
+#include "mesh.h"
+
+wn_mesh *wn_mesh_init(Arena *arena, wn_shader *shader) {
+  // set up vertex data (and buffer(s)) and configure vertex attributes
+  wn_mesh *mesh = (wn_mesh *)arena_init(arena, sizeof(wn_mesh));
+  arena_deinit_task_push(arena, (ArenaDeinitTask){.func_ptr = *wn_mesh_deinit,
+                                                  .func_param = mesh,
+                                                  .next = NULL});
+  mesh->shader = shader;
+  float vertices[] = {
+      0.5f,  0.5f,  0.0f, 1.0f, 1.0f, // top right
+      0.5f,  -0.5f, 0.0f, 1.0f, 0.0f, // bottom right
+      -0.5f, -0.5f, 0.0f, 0.0f, 0.0f, // bottom left
+      -0.5f, 0.5f,  0.0f, 0.0f, 1.0f  // top left
+  };
+  unsigned int indices[] = {
+      0, 1, 3, // first Triangle
+      1, 2, 3  // second Triangle
+  };
+
+  glGenVertexArrays(1, &mesh->VAO);
+  glGenBuffers(1, &mesh->VBO);
+  glGenBuffers(1, &mesh->EBO);
+  // bind the Vertex Array Object first, then bind and set vertex buffer(s), and
+  // then configure vertex attributes(s).
+  glBindVertexArray(mesh->VAO);
+
+  glBindBuffer(GL_ARRAY_BUFFER, mesh->VBO);
+  glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mesh->EBO);
+  glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices,
+               GL_STATIC_DRAW);
+
+  glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void *)0);
+  glEnableVertexAttribArray(0);
+  glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float),
+                        (void *)(3 * sizeof(float)));
+  glEnableVertexAttribArray(1);
+
+  // note that this is allowed, the call to glVertexAttribPointer registered VBO
+  // as the vertex attribute's bound vertex buffer object so afterwards we can
+  // safely unbind
+  // glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+  // remember: do NOT unbind the EBO while a VAO is active as the bound element
+  // buffer object IS stored in the VAO; keep the EBO bound.
+  // glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
+  // You can unbind the VAO afterwards so other VAO calls won't accidentally
+  // modify this VAO, but this rarely happens. Modifying other VAOs requires a
+  // call to glBindVertexArray anyways so we generally don't unbind VAOs (nor
+  // VBOs) when it's not directly necessary.
+  // glBindVertexArray(0);
+
+  // Texture Load
+  SDL_Surface *image = IMG_Load("./data/testxure.png");
+  if (image == NULL) {
+    SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load texture");
+    return NULL;
+  }
+  SDL_FlipSurface(image, SDL_FLIP_VERTICAL);
+
+  GLuint texture;
+  glActiveTexture(GL_TEXTURE0);
+  glGenTextures(1, &texture);
+
+  // Handle different SDL Surface data types
+  // int mode = GL_RGB;
+  //  if (image->format->BytesPerPixel == 4) {
+  int mode = GL_RGBA;
+  //    mode = GL_RGBA;
+  //  }
+
+  glBindTexture(GL_TEXTURE_2D, texture);
+  // set the texture wrapping parameters
+  glTexParameteri(
+      GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
+      GL_REPEAT); // set texture wrapping to GL_REPEAT (default wrapping method)
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+  // set texture filtering parameters
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+  glTexImage2D(GL_TEXTURE_2D, 0, mode, image->w, image->h, 0, mode,
+               GL_UNSIGNED_BYTE, image->pixels);
+
+  glGenerateMipmap(GL_TEXTURE_2D);
+  SDL_DestroySurface(image);
+
+  return mesh;
+}
+
+void wn_mesh_draw(wn_mesh *mesh) {
+  // draw our first triangle
+  glUseProgram(mesh->shader->shaderProgram);
+
+  // seeing as we only have a single VAO there's no need to bind it
+  // every time, but we'll do so to keep things a bit more organized
+  glBindVertexArray(mesh->VAO);
+
+  // glDrawArrays(GL_TRIANGLES, 0, 6);
+  glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+  // glBindVertexArray(0); // no need to unbind it every time
+}
+
+void wn_mesh_deinit(void *mesh) {
+  wn_mesh *cast_mesh = (wn_mesh *)mesh;
+  glDeleteVertexArrays(1, &cast_mesh->VAO);
+  glDeleteBuffers(1, &cast_mesh->VBO);
+  glDeleteBuffers(1, &cast_mesh->EBO);
+}

src/mesh.h

@@ -1,14 +1,20 @@
 #pragma once
 
 #include "SDL3/SDL_opengl.h"
+#include "arena_allocator.h"
 #include "shader.h"
 #include <sys/types.h>
 
 typedef struct {
-  float *vertex_buffer;
-  uint vertex_buffer_size;
-  float *element_buffer;
-  uint element_buffer_size;
   wn_shader *shader;
-  GLuint VBO, VAO, EBO, diffuse_texture;
+  GLuint VBO, VAO, EBO;
-} Mesh;
+} wn_mesh;
+
+// Initialise a model
+wn_mesh *wn_mesh_init(Arena* arena, wn_shader *shader);
+
+// Draw the model with it's linked shader
+void wn_mesh_draw(wn_mesh *mesh);
+
+// Clear up linked buffers
+void wn_mesh_deinit(void* mesh);