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2.10.1 Controlling the Viewport
The viewport transformation is determined by the viewport's
width and height in pixels,
The factor and offset applied to
void DepthRange ( clampd n, clampd f ) ;
Each of n and f are clamped to lie within Viewport transformation parameters are specified using
void Viewport ( int x, int y, sizei w, sizei h ) ;
where x and y give the x and y
window coordinates of the viewport's lower-left
corner
and w and h give the viewport's width and height, respectively.
The viewport parameters shown in the above equations are found from these
values as
Viewport width and height are clamped to implementation-dependent maximums when specified. The maximum width and height may be found by issuing an appropriate Get command (see Chapter 6). The maximum viewport dimensions must be greater than or equal to the visible dimensions of the display being rendered to. INVALID_VALUE is generated if either w or h is negative.
The state required to implement the viewport transformation is 6
integers.
In the initial state,
w and h are set to the width and height,
respectively,
of the window into which the GL is to do its rendering.
![]() ![]() ![]() ![]() ![]() Next: 2.10.2 Matrices Up: 2.10 Coordinate Transformations Previous: 2.10 Coordinate Transformations David Blythe Sat Mar 29 02:23:21 PST 1997
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