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

NAME

6       glPolygonOffset - set the scale and units used to calculate depth
7       values
8

C SPECIFICATION

10       void glPolygonOffset(GLfloat factor, GLfloat units);
11

PARAMETERS

13       factor
14           Specifies a scale factor that is used to create a variable depth
15           offset for each polygon. The initial value is 0.
16
17       units
18           Is multiplied by an implementation-specific value to create a
19           constant depth offset. The initial value is 0.
20

DESCRIPTION

22       When GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, or
23       GL_POLYGON_OFFSET_POINT is enabled, each fragment's depth value will be
24       offset after it is interpolated from the depth values of the
25       appropriate vertices. The value of the offset is factor × DZ + r ×
26       units, where DZ is a measurement of the change in depth relative to the
27       screen area of the polygon, and r is the smallest value that is
28       guaranteed to produce a resolvable offset for a given implementation.
29       The offset is added before the depth test is performed and before the
30       value is written into the depth buffer.
31
32       glPolygonOffset is useful for rendering hidden-line images, for
33       applying decals to surfaces, and for rendering solids with highlighted
34       edges.
35

ASSOCIATED GETS

37       glIsEnabled() with argument GL_POLYGON_OFFSET_FILL,
38       GL_POLYGON_OFFSET_LINE, or GL_POLYGON_OFFSET_POINT.
39
40       glGet() with argument GL_POLYGON_OFFSET_FACTOR or
41       GL_POLYGON_OFFSET_UNITS.
42

SEE ALSO

44       glDepthFunc(), glEnable(), glGet(), glIsEnabled()
45

47       Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed
48       under the SGI Free Software B License. For details, see
49       http://oss.sgi.com/projects/FreeB/.
50

AUTHORS

52       opengl.org
53
54
55
56opengl.org                        06/10/2014               GLPOLYGONOFFSET(3G)
Impressum