glViewport specifies the affine transformation of x and y from normalized device coordinates to window coordinates. Let x nd y nd be normalized device coordinates. Then the window coordinates x w y w are computed as follows: x w = x nd + 1 ⁢ width 2 + x y w = y nd + 1 ⁢ height 2 + y Viewport width and height are silently clamped to a range that depends on the implementation. To query this range, call glGet with argument GL_MAX_VIEWPORT_DIMS.
glViewport: man4/glViewport.xml
glViewport specifies the affine transformation of x and y from normalized device coordinates to window coordinates. Let x nd y nd be normalized device coordinates. Then the window coordinates x w y w are computed as follows: x w = x nd + 1 ⁢ width 2 + x y w = y nd + 1 ⁢ height 2 + y Viewport width and height are silently clamped to a range that depends on the implementation. To query this range, call glGet with argument GL_MAX_VIEWPORT_DIMS.