GLISENABLED(3G)

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/.