UsingFrustum.cpp

Propane::Math::Frustum myNewFrustum;
// To initialize your frustum with whatever you have now, do this:
GLfloat modelView[16];
GLfloat projection[16];

glGetFloatv(GL_MODELVIEW_MATRIX, modelView);
glGetFloatv(GL_PROJECTION_MATRIX, projection);

// In future versions of PI you will be able to use Propane::Math::getMatrix to
// get and wrap the GL matrices and then use them here, which will
// handle the conversion automatically.
myNewFrustum.calculate(modelView, projection);

// Now, to check if a sphere is in our scene, we can go
if(myNewFrustum.isSphereVisible(Vector3(0,0,0), 60)) {
        drawSphere();
}
// Voila! If we can't "see" the sphere, why bother drawing it, right?

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