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OpenGL MFC & openGL?

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Hi. I''m testing openGL with MFC. I have downloaded a test program about it and the only thing it does is painting a cube rotating. When it draws the cube? Well, on the function OnPaint(...). That function calls to RenderScene() function that draws the cube. If you run the application and don''t move the mouse, don''t resize de window, don''t press any key and don''t do nothing the appication continues executing the OnPaint() function, thus makeing the rotation of the cube (an animation). So, why the aplicacion calls OnPaint() function, if I don''t do nothing to invoke a redraw of the window? Has openGL internally something related?, perhaps with the active rendering context, that produce that redraw of the window. Thanks.

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I think MFC calls OnPaint whenever it needs to paint. That''s why you put the OGL rendering function in there. It''s been awhile since I messed with MFC so I could be wrong.

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