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Right And Up Vectors for Camera.

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What are the equations for camera pan up, down, left and right? I want to move the Eye and Lookat at the same time for the Camera pan, so I believe I need to use the Right (1.0, 0.0,0.0) and Up (0.0,1.0,0.0) vectors do so. Anyone have any ideas on what I should do? (Where m_position is the Eye and m_lookat is the LookAt.) 1)Here is what I am doing for doing the camera PAN up: m_lookat+=(m_lookat*distance); m_position+=(m_up*distance); 2) This code is for doing camera PAN to the right: m_lookat-=(m_lookat*distance); m_position-=(m_right*distance); Thanks for the help in advance.

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Oh, boy. Camera stuff. I''ll bet you''re discovering just how much fun it can be , and you ain''t seen nothing yet.

OK. As far as I can tell, you''re using a m_Position vector for the position of your camera in real space and an m_LookAt vector for... What? Basically, there are two possibilities, and you seem to have confused them.

(1) m_LookAt is an actual vector (describing a direction, like m_Up or m_Right) that points away from m_Position in the direction of your focus point. If this is the case, this vector won''t need to be changed - the direction will stay the same as long as you''re panning and not rotating.

(2) m_LookAt is your actual focus point. If this is the case, you will just do the same thing to m_LookAt as you do to m_Position; that is, m_LookAt += (m_Up * distance) for panning up-and-down, and m_LookAt += (m_Right * distance) for panning side-to-side.

That''s half of your problem. Hang on tight for the second part...

You''ll still want the += operator for moving to the right. Again, as in the case of the m_LookAt vector (assuming possibility #2 above is true), you''ll need to multiply the distance by the m_Right vector, not the m_LookAt. I''m not sure what you''re trying to do, adding a positional vector to itself...

That should do it. By the way, you might want to try the math and physics forum, or the game programming forum - this doesn''t seem to be a very DirectX-specific problem. Still, hope I helped.

- TythosEternal

"Who''s John Galt?"

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