基本の２D

#include<GL/glut.h>

void init(char *name) {
	glutInitDisplayMode(GLUT_RGBA);
	glutInitWindowSize(200, 200);
	glutCreateWindow(name);
	glClearColor(1.0, .0, 0.0, 1.0);
}

void display(void) {
	glClear(GL_COLOR_BUFFER_BIT);

	glColor3d(1.0, 1.0, 0.0);
	glBegin(GL_QUADS);
		glVertex2d(0.5, 0.5);
		glVertex2d(-0.5, 0.5);
		glVertex2d(-0.5, -0.5);
		glVertex2d(0.5 , -0.5);
	glEnd();
	
	glFlush();
}

int main(int argc, char **argv){
	glutInit(&argc, argv);
	init(argv[0]);
	glutDisplayFunc(display);
	glutMainLoop();
	return 0;
}