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The Bleu Blue

Question about planes

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I have a question about viewing frustum, for example if the field of view is 90 degrees it is shaped like a pyramid(triangle)...and there are left and right planes of the frustum - there are right and left planes of the frustum that are shaped like a triangle, so my question is, how can be a plane shaped like a triangle?

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well, there are also the front and near planes, which shapes the left/right/top/bottom triangles into quads

The planes are planes, don''t see them as triangles, unless if you want to draw the viewing frustum form another angle, for debug purposes. It''s like faces of a cube can be seen as infinite planes, but other faces cut the other planes into squares. If you want, a cube, a frustum, or any convex shape (cylinders, cones) can be defined as the set of points that backface every possible planes on the surface of the convex shape, which eventually form a pyramid volume for a frustum, or a cubic volume for a cube.

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quote:
Original post by The Bleu Blue
So basically when a plane is drawn like a triangle in the book that is basically just one part of the plane (in a triangle shape)?


Exactly.

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