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Multiple Views

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To draw multiple views in OpenGL you can use what I call "glViewport & glScissor" technique. Draw windows one-by-one.

Drawing window 1

Window 1. If you want to draw a window at bottom left of (x = 100 pixels, y = 80 pixels) with width = 200 pixels, height = 150 pixels.

glEnable(GL_SCISSOR_TEST);
glScissor(100,80,200,150);
glMatrixMode(GL_VIEWPORT);
glViewport(100,80,200,150);
glMatrixMode(GL_MODELVIEW);

As you see - you need to supply SAME coordinates to both viewport and scissor calls.

You might also need to call gluPerspective to update the aspect ratio.

Drawing window 2

Then do the same for Window 2 (with different coordinates)

glEnable(GL_SCISSOR_TEST);
glScissor(320,90,120,150);
glMatrixMode(GL_VIEWPORT);
glViewport(320,90,120,150);
glMatrixMode(GL_MODELVIEW);

Finishing

Then after you are done, you can disable scissoring:

glDisable(GL_SCISSOR_TEST);

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