c-engine/src/main.c
2025-10-01 14:50:20 +01:00

125 lines
3.8 KiB
C

#include <GL/glew.h>
#include <SDL3/SDL.h>
#include <stdlib.h>
#include "SDL3/SDL_events.h"
#include "SDL3/SDL_keycode.h"
#include "camera.h"
#include "shader.h"
#include "window.h"
int main(int argc, char *argv[]) {
wn_window window = {0};
if (!wn_window_init(&window)) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize wn_window");
return EXIT_FAILURE;
}
wn_shader_code_location shader_code_location = {
.vertex_shader_source_path = "shaders/vert.glsl",
.fragment_shader_source_path = "shaders/frag.glsl"};
wn_shader shader = wn_shader_init(shader_code_location);
if (shader.success == false) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize shader");
return EXIT_FAILURE;
}
// set up vertex data (and buffer(s)) and configure vertex attributes
float vertices[] = {
0.5f, 0.5f, 0.0f, // top right
0.5f, -0.5f, 0.0f, // bottom right
-0.5f, -0.5f, 0.0f, // bottom left
-0.5f, 0.5f, 0.0f // top left
};
unsigned int indices[] = {
0, 1, 3, // first Triangle
1, 2, 3 // second Triangle
};
unsigned int 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, 3 * sizeof(float), (void *)0);
glEnableVertexAttribArray(0);
// 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);
// Initialise camera
Camera camera = Camera_default;
bool wants_running = true;
while (wants_running) {
// TODO: Create event handler files
while (SDL_PollEvent(&window.event)) {
switch (window.event.type) {
case SDL_EVENT_QUIT:
wants_running = false;
break;
case SDL_EVENT_KEY_DOWN:
if (window.event.key.key == SDLK_ESCAPE) {
wants_running = false;
}
break;
}
}
// Handle camera
camera_tick(&camera);
// TODO: make shader handler
mat4 mvp;
camera_calc_mvp(&mvp, &camera);
int mvp_uniform_location =
glGetUniformLocation(shader.shaderProgram, "MVP");
glUniformMatrix4fv(mvp_uniform_location, 1, GL_FALSE, &mvp[0][0]);
// render
glClearColor(0.1f, 0.3f, 0.4f, 1.f);
glClear(GL_COLOR_BUFFER_BIT);
// draw our first triangle
glUseProgram(shader.shaderProgram);
glBindVertexArray(
VAO); // 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
// 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);
wn_shader_deinit(shader);
wn_window_deinit(&window);
return EXIT_SUCCESS;
}