glget - Man Page
glGet(3G) OpenGL Reference glGet(3G)
NAME
glGetBooleanv, glGetDoublev, glGetFloatv, glGetIntegerv - return the
value or values of a selected parameter
C SPECIFICATION
void glGetBooleanv( GLenum pname,
GLboolean *params )
C SPECIFICATION
void glGetDoublev( GLenum pname,
GLdouble *params )
C SPECIFICATION
void glGetFloatv( GLenum pname,
GLfloat *params )
C SPECIFICATION
void glGetIntegerv( GLenum pname,
GLint *params )
PARAMETERS
pname Specifies the parameter value to be returned. The symbolic
constants in the list below are accepted.
params Returns the value or values of the specified parameter.
DESCRIPTION
These four commands return values for simple state variables in GL. pname
is a symbolic constant indicating the state variable to be returned, and
params is a pointer to an array of the indicated type in which to place
the returned data.
Type conversion is performed if params has a different type than the
state variable value being requested. If glGetBooleanv is called, a
floating-point or integer value is converted to GL_FALSE if and only if
it is zero. Otherwise, it is converted to GL_TRUE. If glGetIntegerv is
called, Boolean values are returned as GL_TRUE or GL_FALSE, and most
floating-point values are rounded to the nearest integer value.
Floating-point colors and normals, however, are returned with a linear
mapping that maps 1.0 to the most positive representable integer value,
and -1.0 to the most negative representable integer value. If
glGetFloatv or glGetDoublev is called, Boolean values are returned as
GL_TRUE or GL_FALSE, and integer values are converted to floating-point
values.
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glGet(3G) OpenGL Reference glGet(3G)
The following symbolic constants are accepted by pname:
GL_ACCUM_ALPHA_BITS params returns one value, the number of alpha
bitplanes in the accumulation buffer.
GL_ACCUM_BLUE_BITS params returns one value, the number of blue
bitplanes in the accumulation buffer.
GL_ACCUM_CLEAR_VALUE params returns four values: the red, green,
blue, and alpha values used to clear the
accumulation buffer. Integer values, if
requested, are linearly mapped from the internal
floating-point representation such that 1.0
returns the most positive representable integer
value, and -1.0 returns the most negative
representable integer value. See glClearAccum.
GL_ACCUM_GREEN_BITS params returns one value, the number of green
bitplanes in the accumulation buffer.
GL_ACCUM_RED_BITS params returns one value, the number of red
bitplanes in the accumulation buffer.
GL_ALPHA_BIAS params returns one value, the alpha bias factor
used during pixel transfers. See
glPixelTransfer.
GL_ALPHA_BITS params returns one value, the number of alpha
bitplanes in each color buffer.
GL_ALPHA_SCALE params returns one value, the alpha scale factor
used during pixel transfers. See
glPixelTransfer.
GL_ALPHA_TEST params returns a single Boolean value indicating
whether alpha testing of fragments is enabled.
See glAlphaFunc.
GL_ALPHA_TEST_FUNC params returns one value, the symbolic name of
the alpha test function. See glAlphaFunc.
GL_ALPHA_TEST_REF params returns one value, the reference value
for the alpha test. See glAlphaFunc. An
integer value, if requested, is linearly mapped
from the internal floating-point representation
such that 1.0 returns the most positive
representable integer value, and -1.0 returns
the most negative representable integer value.
GL_ATTRIB_STACK_DEPTH params returns one value, the depth of the
attribute stack. If the stack is empty, zero is
returned. See glPushAttrib.
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glGet(3G) OpenGL Reference glGet(3G)
GL_AUTO_NORMAL params returns a single Boolean value indicating
whether 2-D map evaluation automatically
generates surface normals. See glMap2.
GL_AUX_BUFFERS params returns one value, the number of
auxiliary color buffers.
GL_BLEND params returns a single Boolean value indicating
whether blending is enabled. See glBlendFunc.
GL_BLEND_COLOR_EXT params returns four values, the red, green,
blue, and alpha values which are the components
of the blend color. See glBlendColorEXT.
GL_BLEND_DST params returns one value, the symbolic constant
identifying the destination blend function. See
glBlendFunc.
GL_BLEND_EQUATION_EXT params returns one value, a symbolic constant
identifying the blend equation. See
glBlendEquationEXT.
GL_BLEND_SRC params returns one value, the symbolic constant
identifying the source blend function. See
glBlendFunc.
GL_BLEND_OP_SGI params returns one value, the symbolic constant
identifying the blend operator. See
glBlendFunc.
GL_BLUE_BIAS params returns one value, the blue bias factor
used during pixel transfers. See
glPixelTransfer.
GL_BLUE_BITS params returns one value, the number of blue
bitplanes in each color buffer.
GL_BLUE_SCALE params returns one value, the blue scale factor
used during pixel transfers. See
glPixelTransfer.
GL_CLIP_PLANEi params returns a single Boolean value indicating
whether the specified clipping plane is enabled.
See glClipPlane.
GL_COLOR_CLEAR_VALUE params returns four values: the red, green,
blue, and alpha values used to clear the color
buffers. Integer values, if requested, are
linearly mapped from the internal floating-point
representation such that 1.0 returns the most
positive representable integer value, and -1.0
returns the most negative representable integer
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glGet(3G) OpenGL Reference glGet(3G)
value. See glClearColor.
GL_COLOR_MATERIAL params returns a single Boolean value indicating
whether one or more material parameters are
tracking the current color. See
glColorMaterial.
GL_COLOR_MATERIAL_FACE params returns one value, a symbolic constant
indicating which materials have a parameter that
is tracking the current color. See
glColorMaterial.
GL_COLOR_MATERIAL_PARAMETER
params returns one value, a symbolic constant
indicating which material parameters are
tracking the current color. See
glColorMaterial.
GL_COLOR_MATRIX_SGI params returns sixteen values: the color matrix
on the top of the color matrix stack. See
glPushMatrix, glPixelTransfer.
GL_COLOR_MATRIX_STACK_DEPTH_SGI
params returns one value, the maximum supported
depth of the color matrix stack. See
glPushMatrix, glPixelTransfer.
GL_COLOR_TABLE_SGI params returns a single Boolean value indicating
whether colors are passed through a lookup table
before being used by convolution. See
glColorTableSGI.
GL_COLOR_WRITEMASK params returns four Boolean values: the red,
green, blue, and alpha write enables for the
color buffers. See glColorMask.
GL_CONVOLUTION_1D_EXT params returns a single Boolean value indicating
whether one-dimensional convolution will be
performed during pixel transfers. See
glConvolutionFilter1DEXT.
GL_CONVOLUTION_2D_EXT params returns a single Boolean value indicating
whether two-dimensional convolution will be
performed during pixel transfers. See
glConvolutionFilter2DEXT.
GL_CULL_FACE params returns a single Boolean value indicating
whether polygon culling is enabled. See
glCullFace.
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glGet(3G) OpenGL Reference glGet(3G)
GL_CULL_FACE_MODE params returns one value, a symbolic constant
indicating which polygon faces are to be culled.
See glCullFace.
GL_CURRENT_COLOR params returns four values: the red, green,
blue, and alpha values of the current color.
Integer values, if requested, are linearly
mapped from the internal floating-point
representation such that 1.0 returns the most
positive representable integer value, and -1.0
returns the most negative representable integer
value. See glColor.
GL_CURRENT_INDEX params returns one value, the current color
index. See glIndex.
GL_CURRENT_NORMAL params returns three values: the x, y, and z
values of the current normal. Integer values,
if requested, are linearly mapped from the
internal floating-point representation such that
1.0 returns the most positive representable
integer value, and -1.0 returns the most
negative representable integer value. See
glNormal.
GL_CURRENT_RASTER_COLOR params returns four values: the red, green,
blue, and alpha values of the current raster
position. Integer values, if requested, are
linearly mapped from the internal floating-point
representation such that 1.0 returns the most
positive representable integer value, and -1.0
returns the most negative representable integer
value. See glRasterPos.
GL_CURRENT_RASTER_DISTANCE
params returns one value, the distance from the
eye to the current raster position. See
glRasterPos.
GL_CURRENT_RASTER_INDEX params returns one value, the color index of the
current raster position. See glRasterPos.
GL_CURRENT_RASTER_POSITION
params returns four values: the x, y, z, and w
components of the current raster position. x,
y, and z are in window coordinates, and w is in
clip coordinates. See glRasterPos.
GL_CURRENT_RASTER_TEXTURE_COORDS
params returns four values: the s, t, r, and q
current raster texture coordinates. See
glRasterPos and glTexCoord.
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glGet(3G) OpenGL Reference glGet(3G)
GL_CURRENT_RASTER_POSITION_VALID
params returns a single Boolean value indicating
whether the current raster position is valid.
See glRasterPos.
GL_CURRENT_TEXTURE_COORDS
params returns four values: the s, t, r, and q
current texture coordinates. See glTexCoord.
GL_DEPTH_BIAS params returns one value, the depth bias factor
used during pixel transfers. See
glPixelTransfer.
GL_DEPTH_BITS params returns one value, the number of
bitplanes in the depth buffer.
GL_DEPTH_CLEAR_VALUE params returns one value, the value that is used
to clear the depth buffer. Integer values, if
requested, are linearly mapped from the internal
floating-point representation such that 1.0
returns the most positive representable integer
value, and -1.0 returns the most negative
representable integer value. See glClearDepth.
GL_DEPTH_FUNC params returns one value, the symbolic constant
that indicates the depth comparison function.
See glDepthFunc.
GL_DEPTH_RANGE params returns two values: the near and far
mapping limits for the depth buffer. Integer
values, if requested, are linearly mapped from
the internal floating-point representation such
that 1.0 returns the most positive representable
integer value, and -1.0 returns the most
negative representable integer value. See
glDepthRange.
GL_DEPTH_SCALE params returns one value, the depth scale factor
used during pixel transfers. See
glPixelTransfer.
GL_DEPTH_TEST params returns a single Boolean value indicating
whether depth testing of fragments is enabled.
See glDepthFunc and glDepthRange.
GL_DEPTH_WRITEMASK params returns a single Boolean value indicating
if the depth buffer is enabled for writing. See
glDepthMask.
GL_DETAIL_TEXTURE_2D_BINDING_SGIS
params returns a single value, the name of the
detail texture bound to
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glGet(3G) OpenGL Reference glGet(3G)
GL_DETAIL_TEXTURE_2D_SGIS (or zero if there is
none). See glDetailTexFuncSGIS.
GL_DITHER params returns a single Boolean value indicating
whether dithering of fragment colors and indices
is enabled.
GL_DOUBLEBUFFER params returns a single Boolean value indicating
whether double buffering is supported.
GL_DRAW_BUFFER params returns one value, a symbolic constant
indicating which buffers are being drawn to.
See glDrawBuffer.
GL_EDGE_FLAG params returns a single Boolean value indication
whether the current edge flag is true or false.
See glEdgeFlag.
GL_FOG params returns a single Boolean value indicating
whether fogging is enabled. See glFog.
GL_FOG_COLOR params returns four values: the red, green,
blue, and alpha components of the fog color.
Integer values, if requested, are linearly
mapped from the internal floating-point
representation such that 1.0 returns the most
positive representable integer value, and -1.0
returns the most negative representable integer
value. See glFog.
GL_FOG_DENSITY params returns one value, the fog density
parameter. See glFog.
GL_FOG_END params returns one value, the end factor for the
linear fog equation. See glFog.
GL_FOG_FUNC_POINTS_SGIS params returns one value, the number of points
in the current custom fog blending function.
See glFog and glFogFuncSGIS.
GL_FOG_FUNC_SGIS params returns an array of fog blending function
control points. Each control point consists of
two values, an eye-space distance and a blending
factor, in that order. The control points are
listed in order of increasing eye-space
distance. The number of control points may be
queried by glGet with argument
GL_FOG_FUNC_POINTS_SGIS. See glFog and
glFogFuncSGIS.
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glGet(3G) OpenGL Reference glGet(3G)
GL_FOG_HINT params returns one value, a symbolic constant
indicating the mode of the fog hint. See
glHint.
GL_FOG_INDEX params returns one value, the fog color index.
See glFog.
GL_FOG_MODE params returns one value, a symbolic constant
indicating which fog equation is selected. See
glFog.
GL_FOG_OFFSET_SGIX params returns a single Boolean value indicating
whether fog offset is enabled. See glFog.
GL_FOG_OFFSET_VALUE_SGIX params returns four values, a reference point
(X,Y,Z) in eye coordinates, and a Z offset in
eye coordinates. See glFog.
GL_FOG_START params returns one value, the start factor for
the linear fog equation. See glFog.
GL_FRONT_FACE params returns one value, a symbolic constant
indicating whether clockwise or counterclockwise
polygon winding is treated as front-facing. See
glFrontFace.
GL_GREEN_BIAS params returns one value, the green bias factor
used during pixel transfers.
GL_GREEN_BITS params returns one value, the number of green
bitplanes in each color buffer.
GL_GREEN_SCALE params returns one value, the green scale factor
used during pixel transfers. See
glPixelTransfer.
GL_HISTOGRAM_EXT params returns a single Boolean value indicating
whether histogramming is enabled. See
glHistogramEXT.
GL_INDEX_BITS params returns one value, the number of
bitplanes in each color index buffer.
GL_INDEX_CLEAR_VALUE params returns one value, the color index used
to clear the color index buffers. See
glClearIndex.
GL_INDEX_MODE params returns a single Boolean value indicating
whether the GL is in color index mode (true) or
RGBA mode (false).
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glGet(3G) OpenGL Reference glGet(3G)
GL_INDEX_OFFSET params returns one value, the offset added to
color and stencil indices during pixel
transfers. See glPixelTransfer.
GL_INDEX_SHIFT params returns one value, the amount that color
and stencil indices are shifted during pixel
transfers. See glPixelTransfer.
GL_INDEX_WRITEMASK params returns one value, a mask indicating
which bitplanes of each color index buffer can
be written. See glIndexMask.
GL_INTERLACE_SGIX params returns a single Boolean value indicating
whether glCopyPixels and glCopyTexSubImage2DEXT
skip every other line in the destination pixel
array. See glCopyPixels and
glCopyTexSubImage2DEXT.
GL_LIGHTi params returns a single Boolean value indicating
whether the specified light is enabled. See
glLight and glLightModel.
GL_LIGHTING params returns a single Boolean value indicating
whether lighting is enabled. See glLightModel.
GL_LIGHT_MODEL_AMBIENT params returns four values: the red, green,
blue, and alpha components of the ambient
intensity of the entire scene. Integer values,
if requested, are linearly mapped from the
internal floating-point representation such that
1.0 returns the most positive representable
integer value, and -1.0 returns the most
negative representable integer value. See
glLightModel.
GL_LIGHT_MODEL_LOCAL_VIEWER
params returns a single Boolean value indicating
whether specular reflection calculations treat
the viewer as being local to the scene. See
glLightModel.
GL_LIGHT_MODEL_TWO_SIDE params returns a single Boolean value indicating
whether separate materials are used to compute
lighting for front- and back-facing polygons.
See glLightModel.
GL_LINE_SMOOTH params returns a single Boolean value indicating
whether antialiasing of lines is enabled. See
glLineWidth.
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glGet(3G) OpenGL Reference glGet(3G)
GL_LINE_SMOOTH_HINT params returns one value, a symbolic constant
indicating the mode of the line antialiasing
hint. See glHint.
GL_LINE_STIPPLE params returns a single Boolean value indicating
whether stippling of lines is enabled. See
glLineStipple.
GL_LINE_STIPPLE_PATTERN params returns one value, the 16-bit line
stipple pattern. See glLineStipple.
GL_LINE_STIPPLE_REPEAT params returns one value, the line stipple
repeat factor. See glLineStipple.
GL_LINE_WIDTH params returns one value, the line width as
specified with glLineWidth.
GL_LINE_WIDTH_GRANULARITY
params returns one value, the width difference
between adjacent supported widths for
antialiased lines. See glLineWidth.
GL_LINE_WIDTH_RANGE params returns two values: the smallest and
largest supported widths for antialiased lines.
See glLineWidth.
GL_LIST_BASE params returns one value, the base offset added
to all names in arrays presented to glCallLists.
See glListBase.
GL_LIST_INDEX params returns one value, the name of the
display list currently under construction. Zero
is returned if no display list is currently
under construction. See glNewList.
GL_LIST_MODE params returns one value, a symbolic constant
indicating the construction mode of the display
list currently being constructed. See
glNewList.
GL_LOGIC_OP params returns a single Boolean value indicating
whether fragment indexes are merged into the
framebuffer using a logical operation. See
glLogicOp.
GL_LOGIC_OP_MODE params returns one value, a symbolic constant
indicating the selected logic operational mode.
See glLogicOp.
GL_MAP1_COLOR_4 params returns a single Boolean value indicating
whether 1D evaluation generates colors. See
glMap1.
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glGet(3G) OpenGL Reference glGet(3G)
GL_MAP1_GRID_DOMAIN params returns two values: the endpoints of the
1-D map's grid domain. See glMapGrid.
GL_MAP1_GRID_SEGMENTS params returns one value, the number of
partitions in the 1-D map's grid domain. See
glMapGrid.
GL_MAP1_INDEX params returns a single Boolean value indicating
whether 1D evaluation generates color indices.
See glMap1.
GL_MAP1_NORMAL params returns a single Boolean value indicating
whether 1D evaluation generates normals. See
glMap1.
GL_MAP1_TEXTURE_COORD_1 params returns a single Boolean value indicating
whether 1D evaluation generates 1D texture
coordinates. See glMap1.
GL_MAP1_TEXTURE_COORD_2 params returns a single Boolean value indicating
whether 1D evaluation generates 2D texture
coordinates. See glMap1.
GL_MAP1_TEXTURE_COORD_3 params returns a single Boolean value indicating
whether 1D evaluation generates 3D texture
coordinates. See glMap1.
GL_MAP1_TEXTURE_COORD_4 params returns a single Boolean value indicating
whether 1D evaluation generates 4D texture
coordinates. See glMap1.
GL_MAP1_VERTEX_3 params returns a single Boolean value indicating
whether 1D evaluation generates 3D vertex
coordinates. See glMap1.
GL_MAP1_VERTEX_4 params returns a single Boolean value indicating
whether 1D evaluation generates 4D vertex
coordinates. See glMap1.
GL_MAP2_COLOR_4 params returns a single Boolean value indicating
whether 2D evaluation generates colors. See
glMap2.
GL_MAP2_GRID_DOMAIN params returns four values: the endpoints of
the 2-D map's i and j grid domains. See
glMapGrid.
GL_MAP2_GRID_SEGMENTS params returns two values: the number of
partitions in the 2-D map's i and j grid
domains. See glMapGrid.
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glGet(3G) OpenGL Reference glGet(3G)
GL_MAP2_INDEX params returns a single Boolean value indicating
whether 2D evaluation generates color indices.
See glMap2.
GL_MAP2_NORMAL params returns a single Boolean value indicating
whether 2D evaluation generates normals. See
glMap2.
GL_MAP2_TEXTURE_COORD_1 params returns a single Boolean value indicating
whether 2D evaluation generates 1D texture
coordinates. See glMap2.
GL_MAP2_TEXTURE_COORD_2 params returns a single Boolean value indicating
whether 2D evaluation generates 2D texture
coordinates. See glMap2.
GL_MAP2_TEXTURE_COORD_3 params returns a single Boolean value indicating
whether 2D evaluation generates 3D texture
coordinates. See glMap2.
GL_MAP2_TEXTURE_COORD_4 params returns a single Boolean value indicating
whether 2D evaluation generates 4D texture
coordinates. See glMap2.
GL_MAP2_VERTEX_3 params returns a single Boolean value indicating
whether 2D evaluation generates 3D vertex
coordinates. See glMap2.
GL_MAP2_VERTEX_4 params returns a single Boolean value indicating
whether 2D evaluation generates 4D vertex
coordinates. See glMap2.
GL_MAP_COLOR params returns a single Boolean value indicating
if colors and color indices are to be replaced
by table lookup during pixel transfers. See
glPixelTransfer.
GL_MAP_STENCIL params returns a single Boolean value indicating
if stencil indices are to be replaced by table
lookup during pixel transfers. See
glPixelTransfer.
GL_MATRIX_MODE params returns one value, a symbolic constant
indicating which matrix stack is currently the
target of all matrix operations. See
glMatrixMode.
GL_MAX_3D_TEXTURE_SIZE params returns one value, the maximum width,
height, or depth of any texture image (without
borders). See glTexImage3DEXT.
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glGet(3G) OpenGL Reference glGet(3G)
GL_MAX_ATTRIB_STACK_DEPTH
params returns one value, the maximum supported
depth of the attribute stack. See glPushAttrib.
GL_MAX_CLIP_PLANES params returns one value, the maximum number of
application-defined clipping planes. See
glClipPlane.
GL_MAX_CLIPMAP_DEPTH_SGIX
params returns one value, the maximum number of
levels permitted in a clipmap. See
glTexParameter.
GL_MAX_COLOR_MATRIX_STACK_DEPTH_SGI
params returns one value, the maximum supported
depth of the color matrix stack. See
glPushMatrix, glPixelTransfer.
GL_MAX_EVAL_ORDER params returns one value, the maximum equation
order supported by 1-D and 2-D evaluators. See
glMap1 and glMap2.
GL_MAX_FOG_FUNC_POINTS_SGIS
params returns one value, the maximum number of
control points supported in custom fog blending
functions. See glFog and glFogFuncSGIS.
GL_MAX_LIGHTS params returns one value, the maximum number of
lights. See glLight.
GL_MAX_LIST_NESTING params returns one value, the maximum recursion
depth allowed during display-list traversal.
See glCallList.
GL_MAX_MODELVIEW_STACK_DEPTH
params returns one value, the maximum supported
depth of the modelview matrix stack. See
glPushMatrix.
GL_MAX_NAME_STACK_DEPTH params returns one value, the maximum supported
depth of the selection name stack. See
glPushName.
GL_MAX_PIXEL_MAP_TABLE params returns one value, the maximum supported
size of a glPixelMap lookup table. See
glPixelMap.
GL_MAX_PROJECTION_STACK_DEPTH
params returns one value, the maximum supported
depth of the projection matrix stack. See
glPushMatrix.
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glGet(3G) OpenGL Reference glGet(3G)
GL_MAX_TEXTURE_SIZE params returns one value, the maximum width or
height of any texture image (without borders).
See glTexImage1D and glTexImage2D.
GL_MAX_TEXTURE_STACK_DEPTH
params returns one value, the maximum supported
depth of the texture matrix stack. See
glPushMatrix.
GL_MAX_VIEWPORT_DIMS params returns two values: the maximum
supported width and height of the viewport. See
glViewport.
GL_MINMAX_EXT params returns a single Boolean value indicating
whether the pixel transfer min/max computation
is enabled. See glMinmaxEXT.
GL_MODELVIEW_MATRIX params returns sixteen values: the modelview
matrix on the top of the modelview matrix stack.
See glPushMatrix.
GL_MODELVIEW_STACK_DEPTH params returns one value, the number of matrices
on the modelview matrix stack. See
glPushMatrix.
GL_MULTISAMPLE_SGIS params returns a single Boolean value indicating
whether multisampling is enabled. See
glSamplePatternSGIS.
GL_NAME_STACK_DEPTH params returns one value, the number of names on
the selection name stack. See glPushMatrix.
GL_NORMALIZE params returns a single Boolean value indicating
whether normals are automatically scaled to unit
length after they have been transformed to eye
coordinates. See glNormal.
GL_PACK_ALIGNMENT params returns one value, the byte alignment
used for writing pixel data to memory. See
glPixelStore.
GL_PACK_IMAGE_HEIGHT_EXT params returns one value, the image height used
for writing (3D) pixel data to memory. See
glPixelStore.
GL_PACK_LSB_FIRST params returns a single Boolean value indicating
whether single-bit pixels being written to
memory are written first to the least
significant bit of each unsigned byte. See
glPixelStore.
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glGet(3G) OpenGL Reference glGet(3G)
GL_PACK_ROW_LENGTH params returns one value, the row length used
for writing pixel data to memory. See
glPixelStore.
GL_PACK_SKIP_IMAGES_EXT params returns one value, the number of 2D
images skipped before the first pixel is written
into memory. See glPixelStore.
GL_PACK_SKIP_PIXELS params returns one value, the number of pixel
locations skipped before the first pixel is
written into memory. See glPixelStore.
GL_PACK_SKIP_ROWS params returns one value, the number of rows of
pixel locations skipped before the first pixel
is written into memory. See glPixelStore.
GL_PACK_SWAP_BYTES params returns a single Boolean value indicating
whether the bytes of two-byte and four-byte
pixel indices and components are swapped before
being written to memory. See glPixelStore.
GL_PERSPECTIVE_CORRECTION_HINT
params returns one value, a symbolic constant
indicating the mode of the perspective
correction hint. See glHint.
GL_PIXEL_MAP_A_TO_A_SIZE params returns one value, the size of the
alpha-to-alpha pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_B_TO_B_SIZE params returns one value, the size of the blue-
to-blue pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_G_TO_G_SIZE params returns one value, the size of the
green-to-green pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_I_TO_A_SIZE params returns one value, the size of the
index-to-alpha pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_I_TO_B_SIZE params returns one value, the size of the
index-to-blue pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_I_TO_G_SIZE params returns one value, the size of the
index-to-green pixel translation table. See
glPixelMap.
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glGet(3G) OpenGL Reference glGet(3G)
GL_PIXEL_MAP_I_TO_I_SIZE params returns one value, the size of the
index-to-index pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_I_TO_R_SIZE params returns one value, the size of the
index-to-red pixel translation table. See
glPixelMap.
GL_PIXEL_MAP_R_TO_R_SIZE params returns one value, the size of the red-
to-red pixel translation table. See glPixelMap.
GL_PIXEL_MAP_S_TO_S_SIZE params returns one value, the size of the
stencil-to-stencil pixel translation table. See
glPixelMap.
GL_POINT_SIZE params returns one value, the point size as
specified by glPointSize.
GL_POINT_SIZE_GRANULARITY
params returns one value, the size difference
between adjacent supported sizes for antialiased
points. See glPointSize.
GL_POINT_SIZE_RANGE params returns two values: the smallest and
largest supported sizes for antialiased points.
See glPointSize.
GL_POINT_SMOOTH params returns a single Boolean value indicating
whether antialiasing of points is enabled. See
glPointSize.
GL_POINT_SMOOTH_HINT params returns one value, a symbolic constant
indicating the mode of the point antialiasing
hint. See glHint.
GL_POLYGON_MODE params returns two values: symbolic constants
indicating whether front-facing and back-facing
polygons are rasterized as points, lines, or
filled polygons. See glPolygonMode.
GL_POLYGON_OFFSET_EXT params returns a single Boolean value indicating
whether polygon offset is enabled. See
glPolygonOffsetEXT.
GL_POLYGON_OFFSET_BIAS_EXT
params returns one value, the constant which is
added to the z value of each fragment generated
when a polygon is rasterized. See
glPolygonOffsetEXT.
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glGet(3G) OpenGL Reference glGet(3G)
GL_POLYGON_OFFSET_FACTOR_EXT
params returns one value, the scaling factor
used to determine the variable offset which is
added to the z value of each fragment generated
when a polygon is rasterized. See
glPolygonOffsetEXT.
GL_POLYGON_SMOOTH params returns a single Boolean value indicating
whether antialiasing of polygons is enabled.
See glPolygonMode.
GL_POLYGON_SMOOTH_HINT params returns one value, a symbolic constant
indicating the mode of the polygon antialiasing
hint. See glHint.
GL_POLYGON_STIPPLE params returns a single Boolean value indicating
whether stippling of polygons is enabled. See
glPolygonStipple.
GL_POST_COLOR_MATRIX_ALPHA_BIAS_SGI
params returns a single value, the bias term to
be added to alpha immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_ALPHA_SCALE_SGI
params returns a single value, the scale factor
to be applied to alpha immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_BLUE_BIAS_SGI
params returns a single value, the bias term to
be added to blue immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_BLUE_SCALE_SGI
params returns a single value, the scale factor
to be applied to blue immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_COLOR_TABLE_SGI
params returns a single Boolean value indicating
whether colors are passed through a lookup table
before being processed by the histogram
operation. See glColorTableSGI.
GL_POST_COLOR_MATRIX_GREEN_BIAS_SGI
params returns a single value, the bias term to
be added to green immediately after
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glGet(3G) OpenGL Reference glGet(3G)
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_GREEN_SCALE_SGI
params returns a single value, the scale factor
to be applied to green immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_COLOR_MATRIX_RED_BIAS_SGI
params returns a single value, the bias term to
be added to red immediately after multiplication
by the top of the color matrix stack. See
glPixelTransfer.
GL_POST_COLOR_MATRIX_RED_SCALE_SGI
params returns a single value, the scale factor
to be applied to red immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
GL_POST_CONVOLUTION_ALPHA_BIAS_EXT
params returns a single value, the bias term to
be added to alpha immediately after convolution.
See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_ALPHA_SCALE_EXT
params returns a single value, the scale factor
to be applied to alpha immediately after
convolution. See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_BLUE_BIAS_EXT
params returns a single value, the bias term to
be added to blue immediately after convolution.
See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_BLUE_SCALE_EXT
params returns a single value, the scale factor
to be applied to blue immediately after
convolution. See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_COLOR_TABLE_SGI
params returns a single Boolean value indicating
whether colors are passed through a lookup table
Page 18
glGet(3G) OpenGL Reference glGet(3G)
before being processed by the color matrix
operation. See glColorTableSGI.
GL_POST_CONVOLUTION_GREEN_BIAS_EXT
params returns a single value, the bias term to
be added to green immediately after convolution.
See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_GREEN_SCALE_EXT
params returns a single value, the scale factor
to be applied to green immediately after
convolution. See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_RED_BIAS_EXT
params returns a single value, the bias term to
be added to red immediately after convolution.
See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_CONVOLUTION_RED_SCALE_EXT
params returns a single value, the scale factor
to be applied to red immediately after
convolution. See glConvolutionFilter1DEXT,
glConvolutionFilter2DEXT, and
glSeparableFilter2DEXT.
GL_POST_TEXTURE_FILTER_BIAS_RANGE_SGIX
params returns two values: the minimum and
maximum values for the texture bias factors.
See glTexParameterfv and glTexParameteriv.
GL_POST_TEXTURE_FILTER_SCALE_RANGE_SGIX
params returns two values: the minimum and
maximum values for the texture scale factors.
GL_PROJECTION_MATRIX params returns sixteen values: the projection
matrix on the top of the projection matrix
stack.
See glPushMatrix.
GL_PROJECTION_STACK_DEPTH
params returns one value, the number of matrices
on the projection matrix stack. See
glPushMatrix.
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glGet(3G) OpenGL Reference glGet(3G)
GL_READ_BUFFER params returns one value, a symbolic constant
indicating which color buffer is selected for
reading.
See glReadPixels and glAccum.
GL_RED_BIAS params returns one value, the red bias factor
used during pixel transfers.
GL_RED_BITS params returns one value, the number of red
bitplanes in each color buffer.
GL_RED_SCALE params returns one value, the red scale factor
used during pixel transfers. See
glPixelTransfer.
GL_REFERENCE_PLANE_EQUATION_SGIX
params returns four values, the coefficients of
the plane equation for the reference plane,
expressed in clip coordinates. See
glReferencePlaneSGIX.
GL_REFERENCE_PLANE_SGIX params returns a single Boolean value indicating
whether depth values for pixel fragments are
computed from the reference plane (true) or from
the primitive being drawn (false). See
glReferencePlaneSGIX.
GL_RENDER_MODE params returns one value, a symbolic constant
indicating whether the GL is in render, select,
or feedback mode. See glRenderMode.
GL_RGBA_MODE params returns a single Boolean value indicating
whether the GL is in RGBA mode (true) or color
index mode (false). See glColor.
GL_SAMPLE_ALPHA_TO_MASK_SGIS
params returns a single Boolean value indicating
whether fragment alpha values will modify the
multisampling fragment mask. See
glSampleMaskSGIS.
GL_SAMPLE_ALPHA_TO_ONE_SGIS
params returns a single Boolean value indicating
whether fragment alpha will be set to the
maximum possible value after modifying the
multisampling fragment mask. See
glSampleMaskSGIS.
GL_SAMPLE_BUFFERS_SGIS params returns one value, the number of
multisample buffers.
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glGet(3G) OpenGL Reference glGet(3G)
GL_SAMPLE_MASK_INVERT_SGIS
params returns a single Boolean value indicating
whether the multisampling fragment modification
mask is to be inverted. See glSampleMaskSGIS.
GL_SAMPLE_MASK_SGIS params returns a single Boolean value indicating
whether the multisampling fragment mask will be
modified by a coverage mask. See
glSampleMaskSGIS.
GL_SAMPLE_MASK_VALUE_SGIS
params returns one value, the coverage of the
multisampling fragment modification mask. See
glSampleMaskSGIS.
GL_SAMPLE_PATTERN_SGIS params returns one value, a symbolic constant
indicating the multisampling pattern. See
glSamplePatternSGIS.
GL_SAMPLES_SGIS params returns one value, the number of samples
per pixel used for multisampling.
GL_SCISSOR_BOX params returns four values: the x and y window
coordinates of the scissor box, follow by its
width and height. See glScissor.
GL_SCISSOR_TEST params returns a single Boolean value indicating
whether scissoring is enabled. See glScissor.
GL_SEPARABLE_2D_EXT params returns a single Boolean value indicating
whether separable two-dimensional convolution
will be performed during pixel transfers. See
glSeparableFilter2DEXT.
GL_SHADE_MODEL params returns one value, a symbolic constant
indicating whether the shading mode is flat or
smooth. See glShadeModel.
GL_STENCIL_BITS params returns one value, the number of
bitplanes in the stencil buffer.
GL_STENCIL_CLEAR_VALUE params returns one value, the index to which the
stencil bitplanes are cleared. See
glClearStencil.
GL_STENCIL_FAIL params returns one value, a symbolic constant
indicating what action is taken when the stencil
test fails. See glStencilOp.
GL_STENCIL_FUNC params returns one value, a symbolic constant
indicating what function is used to compare the
stencil reference value with the stencil buffer
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glGet(3G) OpenGL Reference glGet(3G)
value. See glStencilFunc.
GL_STENCIL_PASS_DEPTH_FAIL
params returns one value, a symbolic constant
indicating what action is taken when the stencil
test passes, but the depth test fails. See
glStencilOp.
GL_STENCIL_PASS_DEPTH_PASS
params returns one value, a symbolic constant
indicating what action is taken when the stencil
test passes and the depth test passes. See
glStencilOp.
GL_STENCIL_REF params returns one value, the reference value
that is compared with the contents of the
stencil buffer. See glStencilFunc.
GL_STENCIL_TEST params returns a single Boolean value indicating
whether stencil testing of fragments is enabled.
See glStencilFunc and glStencilOp.
GL_STENCIL_VALUE_MASK params returns one value, the mask that is used
to mask both the stencil reference value and the
stencil buffer value before they are compared.
See glStencilFunc.
GL_STENCIL_WRITEMASK params returns one value, the mask that controls
writing of the stencil bitplanes.
glStencilMask.
GL_STEREO params returns a single Boolean value indicating
whether stereo buffers (left and right) are
supported.
GL_SUBPIXEL_BITS params returns one value, an estimate of the
number of bits of subpixel resolution that are
used to position rasterized geometry in window
coordinates.
GL_TEXTURE_1D params returns a single Boolean value indicating
whether 1D texture mapping is enabled. See
glTexImage1D.
GL_TEXTURE_1D_BINDING_EXT
params returns a single value, the name of the
texture currently bound to the target
GL_TEXTURE_1D. See glBindTextureEXT.
GL_TEXTURE_2D params returns a single Boolean value indicating
whether 2D texture mapping is enabled. See
glTexImage2D.
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glGet(3G) OpenGL Reference glGet(3G)
GL_TEXTURE_2D_BINDING_EXT
params returns a single value, the name of the
texture currently bound to the target
GL_TEXTURE_2D. See glBindTextureEXT.
GL_TEXTURE_3D_EXT params returns a single Boolean value indicating
whether 3D texture mapping is enabled. See
glTexImage3DEXT.
GL_TEXTURE_3D_BINDING_EXT
params returns a single value, the name of the
texture currently bound to the target
GL_TEXTURE_3D_EXT. See glBindTextureEXT.
GL_TEXTURE_COLOR_TABLE_SGI
params returns a single Boolean value indicating
whether texture colors are passed through a
lookup table before being used to generate pixel
fragments. See glColorTableSGI.
GL_TEXTURE_GEN_S params returns a single Boolean value indicating
whether automatic generation of the S texture
coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_T params returns a single Boolean value indicating
whether automatic generation of the T texture
coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_R params returns a single Boolean value indicating
whether automatic generation of the R texture
coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_Q params returns a single Boolean value indicating
whether automatic generation of the Q texture
coordinate is enabled. See glTexGen.
GL_TEXTURE_MATRIX params returns sixteen values: the texture
matrix on the top of the texture matrix stack.
See glPushMatrix.
GL_TEXTURE_STACK_DEPTH params returns one value, the number of matrices
on the texture matrix stack. See glPushMatrix.
GL_UNPACK_ALIGNMENT params returns one value, the byte alignment
used for reading pixel data from memory. See
glPixelStore.
GL_UNPACK_IMAGE_HEIGHT_EXT
params returns one value, the image height used
for reading (3D) pixel data from memory. See
glPixelStore.
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glGet(3G) OpenGL Reference glGet(3G)
GL_UNPACK_LSB_FIRST params returns a single Boolean value indicating
whether single-bit pixels being read from memory
are read first from the least significant bit of
each unsigned byte. See glPixelStore.
GL_UNPACK_ROW_LENGTH params returns one value, the row length used
for reading pixel data from memory. See
glPixelStore.
GL_UNPACK_SKIP_IMAGES params returns one value, the number of images
skipped before the first (3D) pixel is read from
memory. See glPixelStore.
GL_UNPACK_SKIP_PIXELS params returns one value, the number of pixel
locations skipped before the first pixel is read
from memory. See glPixelStore.
GL_UNPACK_SKIP_ROWS params returns one value, the number of rows of
pixel locations skipped before the first pixel
is read from memory. See glPixelStore.
GL_UNPACK_SWAP_BYTES params returns a single Boolean value indicating
whether the bytes of two-byte and four-byte
pixel indices and components are swapped after
being read from memory. See glPixelStore.
GL_VIEWPORT params returns four values: the x and y window
coordinates of the viewport, follow by its width
and height. See glViewport.
GL_ZOOM_X params returns one value, the x pixel zoom
factor. See glPixelZoom.
GL_ZOOM_Y params returns one value, the y pixel zoom
factor. See glPixelZoom.
Many of the Boolean parameters can also be queried more easily using
glIsEnabled.
ERRORS
GL_INVALID_ENUM is generated if pname is not an accepted value.
GL_INVALID_OPERATION is generated if glGet is executed between the
execution of glBegin and the corresponding execution of glEnd.
MACHINE DEPENDENCIES
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.
Page 24
glGet(3G) OpenGL Reference glGet(3G)
RealityEngine, RealityEngine2, and VTX and High Impact and Maximum Impact
systems do not support GL_DETAIL_TEXTURE_2D_BINDING_SGIS.
The SGIX_interlace extension is supported only on InfiniteReality systems
and on RealityEngine, RealityEngine2, and VTX systems.
On InfiniteReality systems, if the post-texture filter scale and bias
values are set to values other than the defaults, they are limited to the
range [0.0, 1.0). (note: this range excludes 1.0.) The
SGIX_texture_scale_bias extension is not supported on RealityEngine,
RealityEngine2, and VTX systems or on High Impact and Maximum Impact
systems.
SEE ALSO
glGetClipPlane, glGetError, glGetLight, glGetMap, glGetMaterial,
glGetPixelMap, glGetPolygonStipple, glGetString, glGetTexEnv,
glGetTexGen, glGetTexImage, glGetTexLevelParameter, glGetTexParameter,
glIsEnabled
Page 25