1991-2006 Silicon Graphics, Inc.
glEnable 3G
glEnable enable or disable server-side GL capabilities

## C Specification

void `glEnable` GLenum cap

## Parameters

cap

  Specifies a symbolic constant indicating a GL capability.

## C Specification

void `glDisable` GLenum cap

## Parameters

cap

  Specifies a symbolic constant indicating a GL capability.

## Description

`glEnable` and glDisable enable and disable various capabilities. Use glIsEnabled or glGet to determine the current setting of any capability. The initial value for each capability with the exception of `GL_DITHER` is `GL_FALSE`. The initial value for `GL_DITHER` is `GL_TRUE`.

Both `glEnable` and glDisable take a single argument, cap, which can assume one of the following values:

`GL_BLEND`

  If enabled, blend the computed fragment color values with the values in the color buffers. See glBlendFunc.

`GL_CULL_FACE`

  If enabled, cull polygons based on their winding in window coordinates. See glCullFace.

`GL_DEPTH_TEST`

  If enabled, do depth comparisons and update the depth buffer. Note that even if the depth buffer exists and the depth mask is non-zero, the depth buffer is not updated if the depth test is disabled. See glDepthFunc and glDepthRangef.

`GL_DITHER`

  If enabled, dither color components or indices before they are written to the color buffer.

`GL_POLYGON_OFFSET_FILL`

  If enabled, an offset is added to depth values of a polygon's fragments produced by rasterization. See glPolygonOffset.

`GL_SAMPLE_ALPHA_TO_COVERAGE`

  If enabled, compute a temporary coverage value where each bit is determined by the alpha value at the corresponding sample location. The temporary coverage value is then ANDed with the fragment coverage value.

`GL_SAMPLE_COVERAGE`

  If enabled, the fragment's coverage is ANDed with the temporary coverage value. If `GL_SAMPLE_COVERAGE_INVERT` is set to `GL_TRUE`, invert the coverage value. See glSampleCoverage.

`GL_SCISSOR_TEST`

  If enabled, discard fragments that are outside the scissor rectangle. See glScissor.

`GL_STENCIL_TEST`

  If enabled, do stencil testing and update the stencil buffer. See glStencilFunc and glStencilOp.

## Errors

`GL_INVALID_ENUM` is generated if cap is not one of the values listed previously.

## Associated Gets

glIsEnabled

glGet

## See Also

glActiveTexture, glBlendFunc, glCullFace, glDepthFunc, glDepthRangef, glGet, glIsEnabled, glLineWidth, glPolygonOffset, glScissor, glStencilFunc, glStencilOp, glTexImage2D

## Copyright

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/.