GlScissor: Difference between revisions

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{{PageSyntax}}
{{PageSyntax}}
: SUB _glScissor (BYVAL x AS LONG, BYVAL y AS LONG, BYVAL width AS LONG, BYVAL height AS LONG)
; QB64: SUB _glScissor (BYVAL {{Parameter|x}} AS LONG, BYVAL {{Parameter|y}} AS LONG, BYVAL {{Parameter|width}} AS LONG, BYVAL {{Parameter|height}}) AS LONG)
: void '''_glScissor'''(GLint {{Parameter|x}}, GLint {{Parameter|y}}, GLsizei {{Parameter|width}}, GLsizei {{Parameter|height}});
; C/C++: void '''_glScissor'''(GLint {{Parameter|x}}, GLint {{Parameter|y}}, GLsizei {{Parameter|width}}, GLsizei {{Parameter|height}});




{{PageParameters}}
{{PageParameters}}
;x, y
;x, y: Specify the lower left corner of the scissor box. Initially (0, 0).
: Specify the lower left corner of the scissor box. Initially (0, 0).
; width, height: Specify the width and height of the scissor box. When a GL context is first attached to a window, {{Parameter|width}} and {{Parameter|height}} are set to the dimensions of that window.
; width, height
: Specify the width and height of the scissor box. When a GL context is first attached to a window, {{Parameter|width}} and {{Parameter|height}} are set to the dimensions of that window.




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{{PageCopyright}}
{{PageCopyright}}
Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see [http://oss.sgi.com/projects/FreeB/ http://oss.sgi.com/projects/FreeB/].

Revision as of 08:42, 30 April 2022

This will define the scissor box.


Syntax

QB64
SUB _glScissor (BYVAL x AS LONG, BYVAL y AS LONG, BYVAL width AS LONG, BYVAL height) AS LONG)
C/C++
void _glScissor(GLint x, GLint y, GLsizei width, GLsizei height);


Parameters

x, y
Specify the lower left corner of the scissor box. Initially (0, 0).
width, height
Specify the width and height of the scissor box. When a GL context is first attached to a window, width and height are set to the dimensions of that window.


Description

_glScissor defines a rectangle, called the scissor box, in window coordinates. The first two arguments, x and y, specify the lower left corner of the box. width and height specify the width and height of the box.

To enable and disable the scissor test, call Template:KW and Template:KW with argument Template:KW. The test is initially disabled. While the test is enabled, only pixels that lie within the scissor box can be modified by drawing commands. Window coordinates have integer values at the shared corners of frame buffer pixels. Template:Code allows modification of only the lower left pixel in the window, and Template:Code doesn't allow modification of any pixels in the window.

When the scissor test is disabled, it is as though the scissor box includes the entire window.


Template:PageErrors

Template:KW is generated if either width or height is negative.


Template:PageUseWith

Template:KW with argument Template:KW

Template:KW with argument Template:KW


See also

SUB _GL Template:KW, Template:KW, Template:KW, Template:KW


Template:PageCopyright