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Moved all the mesh init stuff to another file

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This commit is contained in:
Warwick 2026-01-09 20:17:25 +00:00
parent 009a89b907
commit 648a0466ec
3 changed files with 147 additions and 91 deletions
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89
src/main.c
View file

@ -12,6 +12,7 @@
#include "window.h"
#include "arena_allocator.h"
#include "mesh.h"
/*
void test_task(void *data) {
@ -77,7 +78,7 @@ int main(int argc, char *argv[]) {
return EXIT_FAILURE;
}
// set up vertex data (and buffer(s)) and configure vertex attributes
// Set up mesh data
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
@ -89,75 +90,12 @@ int main(int argc, char *argv[]) {
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");
// Create mesh
wn_mesh *mesh = wn_mesh_init(global_arena, vertices, 20, indices, 6, "./data/testxure.png");
if (mesh == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize mesh");
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;
@ -196,23 +134,14 @@ int main(int argc, char *argv[]) {
glClearColor(0.1f, 0.3f, 0.4f, 1.f);
glClear(GL_COLOR_BUFFER_BIT);
// draw our first triangle
// draw our 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_mesh_draw(mesh);
wn_swapwindow(window);
}
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
glDeleteBuffers(1, &EBO);
// Mesh cleanup is handled by arena deinit tasks
arena_deinit(global_arena);
return EXIT_SUCCESS;

119
src/mesh.c
View file

@ -0,0 +1,119 @@
#include "mesh.h"
#include <SDL3/SDL.h>
#include <SDL3/SDL_log.h>
#include <SDL3/SDL_surface.h>
#include <SDL3_image/SDL_image.h>
#include <stdlib.h>
void wn_mesh_deinit(wn_mesh *mesh) {
if (mesh == NULL) {
return;
}
glDeleteVertexArrays(1, &mesh->VAO);
glDeleteBuffers(1, &mesh->VBO);
glDeleteBuffers(1, &mesh->EBO);
if (mesh->texture != 0) {
glDeleteTextures(1, &mesh->texture);
}
}
wn_mesh *wn_mesh_init(Arena *arena, const float *vertices, size_t vertex_count,
const unsigned int *indices, size_t index_count,
const char *texture_path) {
wn_mesh *mesh = arena_alloc(arena, sizeof(wn_mesh));
// Generate OpenGL objects
glGenVertexArrays(1, &mesh->VAO);
glGenBuffers(1, &mesh->VBO);
glGenBuffers(1, &mesh->EBO);
// Store counts
mesh->vertex_count = vertex_count;
mesh->index_count = index_count;
mesh->texture = 0;
// Bind VAO first
glBindVertexArray(mesh->VAO);
// Set up VBO
glBindBuffer(GL_ARRAY_BUFFER, mesh->VBO);
glBufferData(GL_ARRAY_BUFFER, vertex_count * sizeof(float), vertices,
GL_STATIC_DRAW);
// Set up EBO
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mesh->EBO);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, index_count * sizeof(unsigned int),
indices, GL_STATIC_DRAW);
// Set vertex attributes
// Position attribute (location = 0)
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void *)0);
glEnableVertexAttribArray(0);
// Texture coordinate attribute (location = 1)
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float),
(void *)(3 * sizeof(float)));
glEnableVertexAttribArray(1);
// Load texture if path provided
if (texture_path != NULL) {
SDL_Surface *image = IMG_Load(texture_path);
if (image == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load texture: %s",
texture_path);
wn_mesh_deinit(mesh);
return NULL;
}
SDL_FlipSurface(image, SDL_FLIP_VERTICAL);
glActiveTexture(GL_TEXTURE0);
glGenTextures(1, &mesh->texture);
// Determine texture format
int mode = GL_RGBA;
glBindTexture(GL_TEXTURE_2D, mesh->texture);
// Set texture parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Upload texture data
glTexImage2D(GL_TEXTURE_2D, 0, mode, image->w, image->h, 0, mode,
GL_UNSIGNED_BYTE, image->pixels);
glGenerateMipmap(GL_TEXTURE_2D);
SDL_DestroySurface(image);
}
// Unbind VAO
glBindVertexArray(0);
// Register deinit task
arena_deinit_task_push(
arena, (ArenaDeinitTask){.func_param = mesh,
.func_ptr = (void (*)(void *))wn_mesh_deinit});
return mesh;
}
void wn_mesh_draw(wn_mesh *mesh) {
if (mesh == NULL) {
return;
}
// Bind texture if available
if (mesh->texture != 0) {
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, mesh->texture);
}
// Bind VAO and draw
glBindVertexArray(mesh->VAO);
glDrawElements(GL_TRIANGLES, mesh->index_count, GL_UNSIGNED_INT, 0);
glBindVertexArray(0);
}

30
src/mesh.h
View file

@ -1,14 +1,22 @@
#pragma once
#include "SDL3/SDL_opengl.h"
#include "shader.h"
#include <sys/types.h>
#include "arena_allocator.h"
#include <GL/glew.h>
#include <stddef.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;
} Mesh;
typedef struct wn_mesh wn_mesh;
struct wn_mesh {
unsigned int VAO;
unsigned int VBO;
unsigned int EBO;
unsigned int vertex_count;
unsigned int index_count;
GLuint texture;
};
wn_mesh *wn_mesh_init(Arena *arena, const float *vertices, size_t vertex_count,
const unsigned int *indices, size_t index_count,
const char *texture_path);
void wn_mesh_draw(wn_mesh *mesh);
void wn_mesh_deinit(wn_mesh *mesh);