1GLPIXELZOOM(3G)                  OpenGL Manual                 GLPIXELZOOM(3G)
2
3
4

NAME

6       glPixelZoom - specify the pixel zoom factors
7

C SPECIFICATION

9       void glPixelZoom(GLfloat xfactor, GLfloat yfactor);
10

PARAMETERS

12       xfactor, yfactor
13           Specify the x and y zoom factors for pixel write operations.
14

DESCRIPTION

16       glPixelZoom specifies values for the x and y zoom factors. During the
17       execution of glDrawPixels() or glCopyPixels(), if (xr, yr) is the
18       current raster position, and a given element is in the mth row and nth
19       column of the pixel rectangle, then pixels whose centers are in the
20       rectangle with corners at
21
22       (xr + n ⋅ xfactor, yr + m ⋅ yfactor)
23
24       (xr + n + 1 ⋅ xfactor, yr + m + 1 ⋅ yfactor)
25
26       are candidates for replacement. Any pixel whose center lies on the
27       bottom or left edge of this rectangular region is also modified.
28
29       Pixel zoom factors are not limited to positive values. Negative zoom
30       factors reflect the resulting image about the current raster position.
31

ERRORS

33       GL_INVALID_OPERATION is generated if glPixelZoom is executed between
34       the execution of glBegin() and the corresponding execution of glEnd().
35

ASSOCIATED GETS

37       glGet() with argument GL_ZOOM_X
38
39       glGet() with argument GL_ZOOM_Y
40

SEE ALSO

42       glCopyPixels(), glDrawPixels()
43

45       Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed
46       under the SGI Free Software B License. For details, see
47       http://oss.sgi.com/projects/FreeB/.
48

AUTHORS

50       opengl.org
51
52
53
54opengl.org                        06/10/2014                   GLPIXELZOOM(3G)
Impressum