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Core in version 4.6
Core since version 1.0

glPolygonMode: select a polygon rasterization mode

Function Definition

 void glPolygonMode(GLenum face​, GLenum mode​);
Specifies the polygons that mode​ applies to. Must be GL_FRONT_AND_BACK for front- and back-facing polygons.
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.


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​:

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.
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.
The interior of the polygon is filled. Polygon attributes such as GL_POLYGON_SMOOTH control the rasterization of the polygon.


To draw a surface with outlined polygons, call

glPolygonMode(, );


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.


GL_INVALID_ENUM is generated if either face​ or mode​ is not an accepted value.

Associated Gets

glGet with argument GL_POLYGON_MODE

See Also

glLineWidth, glPointSize


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