glViewport

C Specification

void glViewport(
    GLint	 x,
    GLint	 y,
    GLsizei	 width,
    GLsizei	 height)

Parameters

x, y

Specify the lower left corner of the viewport rectangle, in pixels. The initial value is (0, 0).

width, height

Specify the width and height of the viewport. When a GL context is first attached to a window, width and height are set to the dimensions of that window.

Description

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.

Errors

• GL_INVALID_VALUE is generated if either width or height is negative.
• GL_INVALID_OPERATION is generated if glViewport is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

See Also