orca/examples/triangleGLES/main.c

165 lines
3.4 KiB
C

/************************************************************//**
*
* @file: main.cpp
* @author: Martin Fouilleul
* @date: 30/07/2022
* @revision:
*
*****************************************************************/
#include<stdlib.h>
#include<string.h>
#define _USE_MATH_DEFINES //NOTE: necessary for MSVC
#include<math.h>
#define MG_INCLUDE_GL_API 1
#include"milepost.h"
#define LOG_SUBSYSTEM "Main"
unsigned int program;
const char* vshaderSource =
//"#version 320 es\n"
"attribute vec4 vPosition;\n"
"uniform mat4 transform;\n"
"void main()\n"
"{\n"
" gl_Position = transform*vPosition;\n"
"}\n";
const char* fshaderSource =
//"#version 320 es\n"
"precision mediump float;\n"
"void main()\n"
"{\n"
" gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n"
"}\n";
void compile_shader(GLuint shader, const char* source)
{
glShaderSource(shader, 1, &source, 0);
glCompileShader(shader);
int err = glGetError();
if(err)
{
printf("gl error: %i\n", err);
}
int status = 0;
glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
if(!status)
{
char buffer[256];
int size = 0;
glGetShaderInfoLog(shader, 256, &size, buffer);
printf("shader error: %.*s\n", size, buffer);
}
}
int main()
{
LogLevel(LOG_LEVEL_DEBUG);
mp_init();
mp_rect rect = {.x = 100, .y = 100, .w = 800, .h = 600};
mp_window window = mp_window_create(rect, "test", 0);
//NOTE: create surface
mg_surface surface = mg_surface_create_for_window(window, MG_BACKEND_GLES);
mg_surface_prepare(surface);
//NOTE: init shader and gl state
GLuint vao;
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
GLuint vertexBuffer;
glGenBuffers(1, &vertexBuffer);
GLfloat vertices[] = {
-0.866/2, -0.5/2, 0, 0.866/2, -0.5/2, 0, 0, 0.5, 0};
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
unsigned int vshader = glCreateShader(GL_VERTEX_SHADER);
unsigned int fshader = glCreateShader(GL_FRAGMENT_SHADER);
program = glCreateProgram();
compile_shader(vshader, vshaderSource);
compile_shader(fshader, fshaderSource);
glAttachShader(program, vshader);
glAttachShader(program, fshader);
glLinkProgram(program);
int status = 0;
glGetProgramiv(program, GL_LINK_STATUS, &status);
if(!status)
{
char buffer[256];
int size = 0;
glGetProgramInfoLog(program, 256, &size, buffer);
printf("link error: %.*s\n", size, buffer);
}
glUseProgram(program);
mp_window_bring_to_front(window);
// mp_window_focus(window);
while(!mp_should_quit())
{
mp_pump_events(0);
mp_event event = {0};
while(mp_next_event(&event))
{
switch(event.type)
{
case MP_EVENT_WINDOW_CLOSE:
{
mp_request_quit();
} break;
default:
break;
}
}
mg_surface_prepare(surface);
glClearColor(0.3, 0.3, 1, 1);
glClear(GL_COLOR_BUFFER_BIT);
static float alpha = 0;
//f32 aspect = frameSize.x/frameSize.y;
f32 aspect = 800/(f32)600;
GLfloat matrix[] = {cosf(alpha)/aspect, sinf(alpha), 0, 0,
-sinf(alpha)/aspect, cosf(alpha), 0, 0,
0, 0, 1, 0,
0, 0, 0, 1};
alpha += 2*M_PI/120;
glUniformMatrix4fv(0, 1, false, matrix);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);
glEnableVertexAttribArray(0);
glDrawArrays(GL_TRIANGLES, 0, 3);
mg_surface_present(surface);
}
mp_terminate();
return(0);
}