Name: Anonymous 2011-08-29 19:11
So I'm learning OpenGL right now and trying to use glOrtho to scale my sprites correctly, but it doesn't seem to be working. No matter what arguments I pass to glOrtho, it always defaults back to (-1, 1, -1, 1). I checked for GL errors and got nothing. Here is my test code:
void Draw() {
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-100.0, 100.0, -100.0, 100.0, 0.0, 0.0);
glClear(GL_COLOR_BUFFER_BIT);
glLoadIdentity();
glBegin(GL_QUADS);
glColor3f(1.0f, 0.0f, 0.0f);
glVertex2f(-1.0f, 1.0f);
glVertex2f(1.0f, 1.0f);
glVertex2f(1.0f, -1.0f);
glVertex2f(-1.0f, -1.0f);
glEnd();
}
The quad I draw should be tiny, but it covers the entire viewport. Halp!
void Draw() {
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-100.0, 100.0, -100.0, 100.0, 0.0, 0.0);
glClear(GL_COLOR_BUFFER_BIT);
glLoadIdentity();
glBegin(GL_QUADS);
glColor3f(1.0f, 0.0f, 0.0f);
glVertex2f(-1.0f, 1.0f);
glVertex2f(1.0f, 1.0f);
glVertex2f(1.0f, -1.0f);
glVertex2f(-1.0f, -1.0f);
glEnd();
}
The quad I draw should be tiny, but it covers the entire viewport. Halp!