Name

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/.