glEnable(3G)
glEnable, glDisable - enable or disable server-side GL capabilities
As shipped in IRIX 6.5.19. Last changed in IRIX 6.5.19.
NAME glEnable, glDisable - 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_ALPHA_TEST If enabled, do alpha testing. See glAlphaFunc. GL_ASYNC_DRAW_PIXELS_SGIX If enabled, allow subsequent glDrawPixels commands to operate in asynchronous mode. See glDrawPixels. GL_ASYNC_READ_PIXELS_SGIX If enabled, allow subsequent glReadPixels commands to operate in asynchronous mode. See glReadPixels. GL_ASYNC_TEX_IMAGE_SGIX If enabled, allow subsequent glTexImage commands to operate in asynchronous mode. See glTexImage1D, glTexImage2D, glTexImage3D, glTexSubImage1D, glTexSubImage2D, and glTexSubImage3D. GL_AUTO_NORMAL If enabled, generate normal vectors when either GL_MAP2_VERTEX_3 or GL_MAP2_VERTEX_4 is used to generate vertices. See glMap2. GL_BLEND If enabled, blend the incoming RGBA color values with the values in the color buffers. See glBlendFunc. GL_CALLIGRAPHIC_FRAGMENT_SGIX If enabled, send fragment information to the calligraphic interface as fragments are written to the color buffer(s). GL_CLIP_PLANEi If enabled, clip geometry against user-defined clipping plane i. See glClipPlane. GL_COLOR_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer colors from the array supplied to glColorPointerEXT. See glColorPointerEXT. GL_COLOR_LOGIC_OP If enabled, apply the currently selected logical operation to the incoming RGBA color and color buffer values. See glLogicOp. GL_COLOR_MATERIAL If enabled, have one or more material parameters track the current color. See glColorMaterial. GL_COLOR_TABLE If enabled, preform a color table lookup on the incoming RGBA color values. See glColorTable. GL_CONVOLUTION_1D If enabled, perform a 1D convolution operation on incoming RGBA color values. See glConvolutionFilter1D. GL_CONVOLUTION_2D If enabled, perform a 2D convolution operation on incoming RGBA color values. See glConvolutionFilter2D. 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 glDepthRange. GL_DITHER If enabled, dither color components or indices before they are written to the color buffer. GL_EDGE_FLAG_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer edge flags from the array supplied to glEdgeFlagPointerEXT. See glEdgeFlagPointerEXT. GL_FOG If enabled, blend a fog color into the posttexturing color. See glFog. GL_FOG_OFFSET_SGIX If enabled, apply an offset to the Z value used for computing fog. See glFog. GL_FRAGMENT_COLOR_MATERIAL_SGIX If enabled, have one or more fragment material parameters track the current color. See glFragmentColorMaterial. GL_FRAGMENT_LIGHTi_SGIX If enabled, include fragment light i in the evaluation of the lighting equation. See glFragmentLightModel and glFragmentLight. GL_FRAGMENT_LIGHTING_SGIX If enabled, use the current fragment lighting parameters to compute the fragment color or index. Otherwise, simply interpolate the vertex colors or indices across the fragment. See glFragmentMaterial, glFragmentLightModel, and glFragmentLight. GL_HISTOGRAM If enabled, histogram incoming RGBA color values. See glHistogram. GL_INDEX_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer color indices from the array supplied to glIndexPointerEXT. See glIndexPointerEXT. GL_INDEX_LOGIC_OP If enabled, apply the currently selected logical operation to the incoming index and color buffer indices. See glLogicOp. GL_INTERLACE_SGIX If enabled, modifies the behavior of glDrawPixels, glCopyPixels, glTexImage2D, glTexSubImage2DEXT, glCopyTexImage2DEXT and glCopyTexSubImage2DEXT, such that the source image is considered to be a field of an "interlaced" frame. That is, the effective source image has height equal to twice the original height, with rows $(0,2,4,...)$ corresponding to rows $(0,1,2,...)$ of original source image, and rows $(1,3,5,...)$ made of "transparent" pixels that do not affect the corresponding destination pixels in the target image. Thus, two successive operations can be used to assemble a complete frame by interlacing two fields. See the reference pages for the above commands for more details. GL_INTERLACE_READ_INGR If enabled, modifies the behavior of glReadPixels, glCopyPixels, glCopyTexImage2DEXT and glCopyTexSubImage2DEXT. The pixels that are read or copied represent one field of an interlaced frame. The source image height in the framebuffer is equivalent to twice the specified height. Source rows $(0,2,4,...)$ correspond to rows $(0,1,2,...)$ in the destination or intermediate copy image. Rows $(1,3,5,...)$ of the source image are skipped. Two successive operations can be used to extract a pair of interlace fields from an interlaced image in the framebuffer. See the reference pages for the above commands for more details. GL_IR_INSTRUMENT1_SGIX If enabled, allows the gathering of instrument measurements that can be used to identify graphics pipeline bottlenecks. See the reference pages for glFlushRasterSGIX, glGetInstrumentsSGIX, glInstrumentsBufferSGIX, glPollInstrumentsSGIX, glReadInstrumentsSGIX, glStartInstrumentsSGIX, and glStopInstrumentsSGIX for more details. GL_LIGHTi If enabled, include light i in the evaluation of the lighting equation. See glLightModel and glLight. GL_LIGHTING If enabled, use the current lighting parameters to compute the vertex color or index. Otherwise, simply associate the current color or index with each vertex. See glMaterial, glLightModel, and glLight. GL_LINE_SMOOTH If enabled, draw lines with correct filtering. Otherwise, draw aliased lines. See glLineWidth. GL_LINE_STIPPLE If enabled, use the current line stipple pattern when drawing lines. See glLineStipple. GL_MAP1_COLOR_4 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate RGBA values. See glMap1. GL_MAP1_INDEX If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate color indices. See glMap1. GL_MAP1_NORMAL If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate normals. See glMap1. GL_MAP1_TEXTURE_COORD_1 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s texture coordinates. See glMap1. GL_MAP1_TEXTURE_COORD_2 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s and t texture coordinates. See glMap1. GL_MAP1_TEXTURE_COORD_3 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s, t, and r texture coordinates. See glMap1. GL_MAP1_TEXTURE_COORD_4 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s, t, r, and q texture coordinates. See glMap1. GL_MAP1_VERTEX_3 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate x, y, and z vertex coordinates. See glMap1. GL_MAP1_VERTEX_4 If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate homogeneous x, y, z, and w vertex coordinates. See glMap1. GL_MAP2_COLOR_4 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate RGBA values. See glMap2. GL_MAP2_INDEX If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate color indices. See glMap2. GL_MAP2_NORMAL If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate normals. See glMap2. GL_MAP2_TEXTURE_COORD_1 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s texture coordinates. See glMap2. GL_MAP2_TEXTURE_COORD_2 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s and t texture coordinates. See glMap2. GL_MAP2_TEXTURE_COORD_3 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s, t, and r texture coordinates. See glMap2. GL_MAP2_TEXTURE_COORD_4 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s, t, r, and q texture coordinates. See glMap2. GL_MAP2_VERTEX_3 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate x, y, and z vertex coordinates. See glMap2. GL_MAP2_VERTEX_4 If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate homogeneous x, y, z, and w vertex coordinates. See glMap2. GL_MINMAX If enabled, compute the minimum and maximum values of incoming RGBA color values. See glMinmax. GL_MULTISAMPLE_SGIS If enabled, perform multisampling of fragments for single-pass antialiasing and other effects. See glSampleMaskSGIS and glSamplePatternSGIS. GL_NORMAL_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer surface normals from the array supplied to glNormalPointerEXT. See glNormalPointerEXT. GL_NORMALIZE If enabled, normal vectors specified with glNormal are scaled to unit length after transformation. See glNormal. GL_PIXEL_TEX_GEN_SGIX If enabled, pixels drawn with glDrawPixels and glCopyPixels are individually texture-mapped at texture coordinates derived from each pixel's color components. See glPixelTexGenSGIX. GL_PIXEL_TEXTURE_SGIS If enabled, pixels drawn with glDrawPixels and glCopyPixels are individually texture-mapped at texture coordinates derived from color components. See glPixelTexGenParameterSGIS. GL_POINT_SMOOTH If enabled, draw points with proper filtering. Otherwise, draw aliased points. See glPointSize. GL_POLYGON_OFFSET_FILL If enabled, and if the polygon is rendered in GL_FILL mode, an offset is added to depth values of a polygon's fragments before the depth comparison is performed. See glPolygonOffset. GL_POLYGON_OFFSET_LINE If enabled, and if the polygon is rendered in GL_LINE mode, an offset is added to depth values of a polygon's fragments before the depth comparison is performed. See glPolygonOffset. GL_POLYGON_OFFSET_POINT If enabled, an offset is added to depth values of a polygon's fragments before the depth comparison is performed, if the polygon is rendered in GL_POINT mode. See glPolygonOffset. GL_POLYGON_SMOOTH If enabled, draw polygons with proper filtering. Otherwise, draw aliased polygons. For correct anti-aliased polygons, an alpha buffer is needed and the polygons must be sorted front to back. GL_POLYGON_STIPPLE If enabled, use the current polygon stipple pattern when rendering polygons. See glPolygonStipple. GL_POST_COLOR_MATRIX_COLOR_TABLE If enabled, preform a color table lookup on RGBA color values after color matrix transformation. See glColorTable. GL_POST_CONVOLUTION_COLOR_TABLE If enabled, preform a color table lookup on RGBA color values after convolution. See glColorTable. GL_REFERENCE_PLANE_SGIX If enabled, depth values for pixel fragments are computed from a reference plane rather than from the primitive being drawn. See glReferencePlaneSGIX. GL_SAMPLE_ALPHA_TO_MASK_SGIS If enabled, convert fragment alpha values to multisample coverage modification masks. See glSampleMaskSGIS. GL_SAMPLE_ALPHA_TO_ONE_SGIS If enabled, set fragment alpha to the maximum permissible value after computing multisample coverage modification masks. See glSampleMaskSGIS. GL_SAMPLE_MASK_SGIS If enabled, apply a mask to modify fragment coverage during multisampling. See glSampleMaskSGIS. GL_RESCALE_NORMAL If enabled, normal vectors specified with glNormal are scaled to unit length after transformation. See glNormal. GL_SEPARABLE_2D If enabled, perform a two-dimensional convolution operation using a separable convolution filter on incoming RGBA color values. See glSeparableFilter2D. GL_SCISSOR_TEST If enabled, discard fragments that are outside the scissor rectangle. See glScissor. GL_SEPARABLE_2D_EXT If enabled, perform separable two-dimensional convolution during pixel transfers. See glSeparableFilter2DEXT. GL_SPRITE_SGIX If enabled, rotate geometry to face the viewer. See glSpriteParameterSGIX. GL_STENCIL_TEST If enabled, do stencil testing and update the stencil buffer. See glStencilFunc and glStencilOp. GL_TEXTURE_1D If enabled, one-dimensional texturing is performed (unless two- or three-dimensional texturing is also enabled). See glTexImage1D. GL_TEXTURE_2D If enabled, two-dimensional texturing is performed (unless three-dimensional texturing is also enabled). See glTexImage2D. GL_TEXTURE_3D If enabled, three-dimensional texturing is performed. See glTexImage3D. GL_TEXTURE_COLOR_TABLE_SGI If enabled, the colors produced by texturing are mapped by a lookup table before being used to generate pixel fragments. See glColorTableSGI. GL_TEXTURE_COORD_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer texture coordinates from the array supplied to glTexCoordPointerEXT. See glTexCoordPointerEXT. GL_TEXTURE_GEN_Q If enabled, the q texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current q texture coordinate is used. See glTexGen. GL_TEXTURE_GEN_R If enabled, the r texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current r texture coordinate is used. See glTexGen. GL_TEXTURE_GEN_S If enabled, the s texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current s texture coordinate is used. See glTexGen. GL_TEXTURE_GEN_T If enabled, the t texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current t texture coordinate is used. See glTexGen. GL_VERTEX_ARRAY_EXT If enabled, glArrayElementEXT and glDrawArraysEXT will transfer vertex coordinates from the array supplied to glVertexPointerEXT. See glVertexPointerEXT. GL_VERTEX_PRECLIP_SGIX If enabled, vertex data will be preprocessed, and if necessary the vertices will be preclipped, in order to enhance the precision of parameter interpolation over the area of the primitive. NOTES GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, GL_POLYGON_OFFSET_POINT, GL_COLOR_LOGIC_OP, and GL_INDEX_LOGIC_OP 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_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 GL_ARB_imaging is returned from glGet with an argument of GL_EXTENSIONS. ERRORS GL_INVALID_ENUM is generated if cap is not one of the values listed previously. GL_INVALID_OPERATION is generated if glEnable or glDisable is executed between the execution of glBegin and the corresponding execution of glEnd. MACHINE DEPENDENCIES The SGIX_async and SGIX_async_pixel extensions are implemented only on Octane2 VPro systems. GL_COLOR_TABLE_SGI, GL_POST_COLOR_MATRIX_COLOR_TABLE_SGI and GL_POST_CONVOLUTION_COLOR_TABLE_SGI are part of the SGI_color_table extension which is not supported on RealityEngine, RealityEngine2, and VTX systems. The SGIX_fragment_lighting extension is supported only on Octane2 VPro systems. On Octane2 VPro systems, glLightModel with GL_SEPARATE_SPECULAR_COLOR is not compatible with fragment lighting. If fragment lighting is enabled, it will override the separate specular color light model. The SGIX_interlace extension is supported only on InfiniteReality systems, on RealityEngine, RealityEngine2, and VTX systems, on Octane2 VPro systems, and on O2 systems. The INGR_interlace_read extension is supported only on Octane2 VPro systems, and on O2 systems. GL_PIXEL_TEXTURE_SGIS is part of the SGIS_pixel_texture extension, which is supported only on Octane2 VPro systems. On Octane2 VPro systems, use of the texture q coordinate to achieve projective texture effects will be processed on a per-vertex basis instead of a per-pixel basis, unless the texture matrix is set up to be projective. (A projective texture matrix, specified as 16-element array M, is defined to be one in which any of the M[3], M[7], or M[11] array elements is non-zero.) In addition, if either two-sided lighting or fragment lighting or separate specular lighting is in effect, projective texture effects will always be processed on a per-vertex basis. On RealityEngine, RealityEngine2, and VTX systems, do not enable or disable GL_VERTEX_ARRAY, GL_VERTEX_ARRAY_EXT, GL_NORMAL_ARRAY, GL_NORMAL_ARRAY_EXT, GL_COLOR_ARRAY, GL_COLOR_ARRAY_EXT, GL_INDEX_ARRAY,GL_INDEX_ARRAY_EXT, GL_TEXTURE_COORD_ARRAY, GL_TEXTURE_COORD_ARRAY_EXT, GL_EDGE_FLAG_ARRAY or GL_EDGE_FLAG_ARRAY_EXT between a call to glNewList and the corresponding call to glEndList. Instead, enable or disable before the call to glNewList. The SGIX_vertex_preclip extension is supported only on Octane2 VPro systems. SEE ALSO glAlphaFunc, glBlendFunc, glClipPlane, glColorMaterial, glCullFace, glDepthFunc, glDepthRange, glEnableClientState, glFog, glFragmentColorMaterial, glFragmentLight, glFragmentLightModel, glFragmentMaterial, glGet, glIsEnabled, glLight, glLightModel, glLineWidth, glLineStipple, glLogicOp, glMap1, glMap2, glMaterial, glNormal, glPixelTexGenParameterSGIS, glPointSize, glPolygonMode, glPolygonOffset, glPolygonStipple, glReferencePlaneSGIX, glScissor, glStencilFunc, glStencilOp, glTexGen, glTexImage1D, glTexImage2D, glTexImage3D