my_glut/demo/main.c

#include <stdlib.h>
#include <stdio.h>

#include <GLES2/gl2.h>

#include <glut.h>
#include <glut_extensions.h>

const int TARGET_FPS = 15;
static int ONE_TICK_MS = 1000 / TARGET_FPS;

float viewSize = 2.0f;
float aspect_ratio;
int steps = 60;

/* don't want to implement */
/* also removed 
	glEnable(GL_ALPHA_TEST);
	glDisable(GL_ALPHA_TEST);
*/
GLuint GLUT_COMPATIBILITY_PROFILE = 0 ;
GLuint GLUT_SINGLE = 0 ; 
GLuint GLUT_RGBA = 0 ;
const GLuint GLUT_SCREEN_WIDTH = 0;
const GLuint GLUT_SCREEN_HEIGHT = 1;

void glutInitContextVersion( int maj, int min){}
void glutInitContextProfile( GLuint profile){}
void glutInitDisplayMode( GLuint OR_ed_FLAGS){}

int glutGet(GLuint dimension){
	switch( dimension) {
		case 0 :
			return 1920;
		break;
		case 1 :
			return 1152;
		break;
		default:
			exit(1);
	}
}

//funky stuff ahead
void renderLoop() {

	glClearColor( 0.0f, 1.0f, 0.0f, 1.0f);
	glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	glutSwapBuffers();
}

void timer(int value) {
	printf("crashes here\n");
	uint8_t touch_count;
	touch_event **touch_buffer;
	glutGetTouchProxy().get_tracked_events( &touch_buffer, &touch_count);
	printf("%d touch_events\n", touch_count);
	if( touch_count)
		free_touch_events_array( touch_buffer, touch_count);

	/*would have handled animations*/
	glutTimerFunc(ONE_TICK_MS, timer, 0);
	glutPostRedisplay();
}

void keypressed(unsigned char key, int x, int y) {
	printf("pressed key %d\n", key);
}

void mousemoved(int x, int y) {
	//camera.mouseMotion(x, y);
}

int main(int argc, char* argv[])  {
	printf("i'm alive!\n");
	glutInit(&argc, argv);
	glutInitContextVersion(4, 0);
	glutInitContextProfile(GLUT_COMPATIBILITY_PROFILE);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);

	int scrWidth = glutGet(GLUT_SCREEN_WIDTH) * 5 / 6;
	int scrHeight = glutGet(GLUT_SCREEN_HEIGHT) * 5 / 6;
	//scrWidth = 640;
	//scrHeight = 480;
	aspect_ratio = ( (float) scrWidth) / scrHeight;
	glutInitWindowSize( scrWidth , scrHeight );
	glutInitWindowPosition( 0, 0);
	glutCreateWindow("TriDi");

	glutTimerFunc(ONE_TICK_MS, timer, 0);
	glutDisplayFunc(renderLoop);
	glutKeyboardFunc(keypressed);
	glutPassiveMotionFunc(mousemoved);

	/*check what MESA has to offer*/
	const GLubyte *extensions = glGetString(GL_EXTENSIONS);
	printf("%s\n", extensions);

	glutMainLoop();
}