# glViewport

Definition: | include pGUI.e include opengl.e glViewport(integer x, y, w, h)
Description: | The glViewport function sets the viewport. x,y: The lower-left corner of the viewport rectangle, in pixels. The default is (0,0). width,height: The width and height of the viewport. When an OpenGL context is first attached to a window, width and height are set to the dimensions of that window. If either width or height was negative, glGetError() will return GL_INVALID_VALUE. If this routine is called between glBegin() and glEnd(), glGetError() will return GL_INVALID_OPERATION.
pwa/p2js: | Supported.
Remarks | The glViewport function specifies the affine transformation of x and y from normalized device coordinates to window coordinates. Let (xnd, ynd) be normalized device coordinates. The window coordinates (xw, yw) are then computed as follows: Viewport width and height are silently clamped to a range that depends on the implementation. This range is queried by calling glGet with argument GL_MAX_VIEWPORT_DIMS. The following functions retrieve information related to glViewport: glGet with argument GL_VIEWPORT glGet with argument GL_MAX_VIEWPORT_DIMS
See Also: | glBegin, int_to_bits DEV See also --glBegin glDepthRange