Name

glIsEnabled — test whether a capability is enabled

C Specification

GLboolean glIsEnabled(GLenum cap);
 

Parameters

cap

Specifies a symbolic constant indicating a GL capability.

Description

glIsEnabled returns GL_TRUE if cap is an enabled capability and returns GL_FALSE otherwise. Initially all capabilities except GL_DITHER are disabled; GL_DITHER is initially enabled.

The following capabilities are accepted for cap:

Constant See
GL_ALPHA_TEST glAlphaFunc
GL_AUTO_NORMAL glEvalCoord
GL_BLEND glBlendFunc, glLogicOp
GL_CLIP_PLANEi glClipPlane
GL_COLOR_ARRAY glColorPointer
GL_COLOR_LOGIC_OP glLogicOp
GL_COLOR_MATERIAL glColorMaterial
GL_COLOR_SUM glSecondaryColor
GL_COLOR_TABLE glColorTable
GL_CONVOLUTION_1D glConvolutionFilter1D
GL_CONVOLUTION_2D glConvolutionFilter2D
GL_CULL_FACE glCullFace
GL_DEPTH_TEST glDepthFunc, glDepthRange
GL_DITHER glEnable
GL_EDGE_FLAG_ARRAY glEdgeFlagPointer
GL_FOG glFog
GL_FOG_COORD_ARRAY glFogCoordPointer
GL_HISTOGRAM glHistogram
GL_INDEX_ARRAY glIndexPointer
GL_INDEX_LOGIC_OP glLogicOp
GL_LIGHTi glLightModel, glLight
GL_LIGHTING glMaterial, glLightModel, glLight
GL_LINE_SMOOTH glLineWidth
GL_LINE_STIPPLE glLineStipple
GL_MAP1_COLOR_4 glMap1
GL_MAP1_INDEX glMap1
GL_MAP1_NORMAL glMap1
GL_MAP1_TEXTURE_COORD_1 glMap1
GL_MAP1_TEXTURE_COORD_2 glMap1
GL_MAP1_TEXTURE_COORD_3 glMap1
GL_MAP1_TEXTURE_COORD_4 glMap1
GL_MAP2_COLOR_4 glMap2
GL_MAP2_INDEX glMap2
GL_MAP2_NORMAL glMap2
GL_MAP2_TEXTURE_COORD_1 glMap2
GL_MAP2_TEXTURE_COORD_2 glMap2
GL_MAP2_TEXTURE_COORD_3 glMap2
GL_MAP2_TEXTURE_COORD_4 glMap2
GL_MAP2_VERTEX_3 glMap2
GL_MAP2_VERTEX_4 glMap2
GL_MINMAX glMinmax
GL_MULTISAMPLE glSampleCoverage
GL_NORMAL_ARRAY glNormalPointer
GL_NORMALIZE glNormal
GL_POINT_SMOOTH glPointSize
GL_POINT_SPRITE glEnable
GL_POLYGON_SMOOTH glPolygonMode
GL_POLYGON_OFFSET_FILL glPolygonOffset
GL_POLYGON_OFFSET_LINE glPolygonOffset
GL_POLYGON_OFFSET_POINT glPolygonOffset
GL_POLYGON_STIPPLE glPolygonStipple
GL_POST_COLOR_MATRIX_COLOR_TABLE glColorTable
GL_POST_CONVOLUTION_COLOR_TABLE glColorTable
GL_RESCALE_NORMAL glNormal
GL_SAMPLE_ALPHA_TO_COVERAGE glSampleCoverage
GL_SAMPLE_ALPHA_TO_ONE glSampleCoverage
GL_SAMPLE_COVERAGE glSampleCoverage
GL_SCISSOR_TEST glScissor
GL_SECONDARY_COLOR_ARRAY glSecondaryColorPointer
GL_SEPARABLE_2D glSeparableFilter2D
GL_STENCIL_TEST glStencilFunc, glStencilOp
GL_TEXTURE_1D glTexImage1D
GL_TEXTURE_2D glTexImage2D
GL_TEXTURE_3D glTexImage3D
GL_TEXTURE_COORD_ARRAY glTexCoordPointer
GL_TEXTURE_CUBE_MAP glTexImage2D
GL_TEXTURE_GEN_Q glTexGen
GL_TEXTURE_GEN_R glTexGen
GL_TEXTURE_GEN_S glTexGen
GL_TEXTURE_GEN_T glTexGen
GL_VERTEX_ARRAY glVertexPointer
GL_VERTEX_PROGRAM_POINT_SIZE glEnable
GL_VERTEX_PROGRAM_TWO_SIDE glEnable

Notes

If an error is generated, glIsEnabled returns 0.

GL_COLOR_LOGIC_OP, GL_COLOR_ARRAY, GL_EDGE_FLAG_ARRAY, GL_INDEX_ARRAY, GL_INDEX_LOGIC_OP, GL_NORMAL_ARRAY, GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, GL_POLYGON_OFFSET_POINT, GL_TEXTURE_COORD_ARRAY, and GL_VERTEX_ARRAY are available only if the GL version is 1.1 or greater.

GL_RESCALE_NORMAL, and GL_TEXTURE_3D are available only if the GL version is 1.2 or greater.

GL_MULTISAMPLE, GL_SAMPLE_ALPHA_TO_COVERAGE, GL_SAMPLE_ALPHA_TO_ONE, GL_SAMPLE_COVERAGE, GL_TEXTURE_CUBE_MAP are available only if the GL version is 1.3 or greater.

GL_FOG_COORD_ARRAY and GL_SECONDARY_COLOR_ARRAY are available only if the GL version is 1.4 or greater.

GL_POINT_SPRITE, GL_VERTEX_PROGRAM_POINT_SIZE, and GL_VERTEX_PROGRAM_TWO_SIDE are available only if the GL version is 2.0 or greater.

GL_COLOR_TABLE, GL_CONVOLUTION_1D, GL_CONVOLUTION_2D, GL_HISTOGRAM, GL_MINMAX, GL_POST_COLOR_MATRIX_COLOR_TABLE, GL_POST_CONVOLUTION_COLOR_TABLE, and GL_SEPARABLE_2D are available only if ARB_imaging is returned when glGet is called with GL_EXTENSIONS.

For OpenGL versions 1.3 and greater, or when the ARB_multitexture extension is supported, the following parameters return the associated value for the active texture unit: GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_TEXTURE_CUBE_MAP, GL_TEXTURE_GEN_S, GL_TEXTURE_GEN_T, GL_TEXTURE_GEN_R, GL_TEXTURE_GEN_Q, GL_TEXTURE_MATRIX, and GL_TEXTURE_STACK_DEPTH. Likewise, the following parameters return the associated value for the active client texture unit: GL_TEXTURE_COORD_ARRAY, GL_TEXTURE_COORD_ARRAY_SIZE, GL_TEXTURE_COORD_ARRAY_STRIDE, GL_TEXTURE_COORD_ARRAY_TYPE.

Errors

GL_INVALID_ENUM is generated if cap is not an accepted value.

GL_INVALID_OPERATION is generated if glIsEnabled is executed between the execution of glBegin and the corresponding execution of glEnd.

See Also

glEnable, glEnableClientState, glGet

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/.