glPolygonMode.3G - Man Page
select a polygon rasterization mode
C Specification
void glPolygonMode(GLenum face, GLenum mode);
Parameters
- face
Specifies the polygons that mode applies to. Must be GL_FRONT_AND_BACK for front- and back-facing polygons.
- mode
Specifies how polygons will be rasterized. Accepted values are GL_POINT, GL_LINE, and GL_FILL. The initial value is GL_FILL for both front- and back-facing polygons.
Description
glPolygonMode controls the interpretation of polygons for rasterization. face describes which polygons mode applies to: both front and back-facing polygons (GL_FRONT_AND_BACK). The polygon mode affects only the final rasterization of polygons. In particular, a polygon's vertices are lit and the polygon is clipped and possibly culled before these modes are applied.
Three modes are defined and can be specified in mode:
- GL_POINT
Polygon vertices that are marked as the start of a boundary edge are drawn as points. Point attributes such as GL_POINT_SIZE and GL_POINT_SMOOTH control the rasterization of the points. Polygon rasterization attributes other than GL_POLYGON_MODE have no effect.
- GL_LINE
Boundary edges of the polygon are drawn as line segments. Line attributes such as GL_LINE_WIDTH and GL_LINE_SMOOTH control the rasterization of the lines. Polygon rasterization attributes other than GL_POLYGON_MODE have no effect.
- GL_FILL
The interior of the polygon is filled. Polygon attributes such as GL_POLYGON_SMOOTH control the rasterization of the polygon.
Examples
To draw a surface with outlined polygons, call
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
Notes
Vertices are marked as boundary or nonboundary with an edge flag. Edge flags are generated internally by the GL when it decomposes triangle stips and fans.
Errors
GL_INVALID_ENUM is generated if either face or mode is not an accepted value.
Associated Gets
glGet() with argument GL_POLYGON_MODE
Version Support
| OpenGL Version | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Function / Feature Name | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5 |
| glPolygonMode | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
See Also
glLineWidth(), glPointSize()
Copyright
Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2014 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.
Copyright
Copyright © 1991-2006 Silicon Graphics, Inc.
Copyright © 2010-2014 Khronos Group
Referenced By
glEdgeFlag.3G(3), glEnable.3G(3), glFeedbackBuffer.3G(3).