glEnable(3G) OpenGL Reference glEnable(3G)
glEnable, glDisable - enable or disable server-side GL capabilities
void glEnable( GLenum cap )
cap Specifies a symbolic constant indicating a GL capability.
void glDisable( GLenum cap )
cap Specifies a symbolic constant indicating a GL capability.
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 [Toc] [Back]
If enabled, allow subsequent glDrawPixels
commands to operate in asynchronous mode. See
glDrawPixels.
GL_ASYNC_READ_PIXELS_SGIX [Toc] [Back]
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
GL_CALLIGRAPHIC_FRAGMENT_SGIX [Toc] [Back]
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
GL_FOG_OFFSET_SGIX If enabled, apply an offset to the Z value used
for computing fog. See glFog.
GL_FRAGMENT_COLOR_MATERIAL_SGIX [Toc] [Back]
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 [Toc] [Back]
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
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glEnable(3G) OpenGL Reference glEnable(3G)
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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 [Toc] [Back]
If enabled, preform a color table lookup on RGBA
color values after color matrix transformation.
See glColorTable.
GL_POST_CONVOLUTION_COLOR_TABLE [Toc] [Back]
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 [Toc] [Back]
If enabled, convert fragment alpha values to
multisample coverage modification masks. See
glSampleMaskSGIS.
GL_SAMPLE_ALPHA_TO_ONE_SGIS [Toc] [Back]
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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 [Toc] [Back]
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 [Toc] [Back]
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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.
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.
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.
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glEnable(3G) OpenGL Reference glEnable(3G)
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 the texture matrix is set up to
be projective. (A projective texture matrix is defined to be one in
which any of the 13th, 14th or 15th elements is non-zero.) In addition,
if either two-sided lighting or fragment 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.
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
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