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Help with view frustum

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Maybe this question was asked a lot :o How can I get if an object is inside the view frustum? For example: I have a box, and while I move the camera, I want to know if the box is inside the frustum or not. Thanks.

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I think your the 4th this week (my self included) :)

Basically your frustum is made up of 6 planes that all face inward, so we simply find the distance of a point (pt) to each plane. If any are negative then the point must be outside of the frustum.

int p;
for( p = 0; p < 6; p++ )
if( viewFrustum[p].a * pt.x + viewFrustum[p].b * pt.y + viewFrustum[p].c * pt.z + viewFrustum[p].d <= 0 )
return NEGATIVE;
return POSITIVE;

If you don’t have those 6 planes then you need to construct them each frame.
You can find more GL related info here

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