glGetBooleanv,
glGetDoublev, glGetFloatv, glGetIntegerv
[New
- Windows 95, OEM Service Release 2]
These
functions return the value or values of a selected parameter.
void glGetBooleanv(
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GLenum pname, |
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GLboolean * params |
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); |
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void glGetDoublev(
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GLenum pname, |
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GLdouble * params |
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); |
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void glGetFloatv(
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GLenum pname, |
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GLfloat * params |
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); |
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void glGetIntegerv(
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GLenum pname, |
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GLint * params |
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); |
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Parameters
pname
The parameter
value to be returned. The following symbolic constants are accepted:
GL_ACCUM_ALPHA_BITS
The params
parameter returns one value: the number of alpha bitplanes in the accumulation
buffer.
GL_ACCUM_BLUE_BITS
The params
parameter returns one value: the number of blue bitplanes in the accumulation
buffer.
GL_ACCUM_CLEAR_VALUE
The params
parameter 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
The params
parameter returns one value: the number of green bitplanes in the accumulation
buffer.
GL_ACCUM_RED_BITS
The params
parameter returns one value: the number of red bitplanes in the accumulation
buffer.
GL_ALPHA_BIAS
The params
parameter returns one value: the alpha bias factor used during pixel transfers.
See glPixelTransfer.
GL_ALPHA_BITS
The params
parameter returns one value: the number of alpha bitplanes in each color
buffer.
GL_ALPHA_SCALE
The params
parameter returns one value: the alpha scale factor used during pixel
transfers. See glPixelTransfer.
GL_ALPHA_TEST
The params
parameter returns a single Boolean value indicating whether alpha testing of
fragments is enabled. See glAlphaFunc.
GL_ALPHA_TEST_FUNC
The params
parameter returns one value: the symbolic name of the alpha test function. See glAlphaFunc.
GL_ALPHA_TEST_REF
The params
parameter 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
The params
parameter returns one value: the depth of the attribute stack. If the stack is
empty, zero is returned. See glPushAttrib.
GL_AUTO_NORMAL
The params
parameter returns a single Boolean value indicating whether 2-D map evaluation
automatically generates surface normals. See glMap2.
GL_AUX_BUFFERS
The params
parameter returns one value: the number of auxiliary color buffers.
GL_BLEND
The params
parameter returns a single Boolean value indicating whether blending is
enabled. See glBlendFunc.
GL_BLEND_DST
The params
parameter returns one value: the symbolic constant identifying the destination
blend function. See glBlendFunc.
GL_BLEND_SRC
The params
parameter returns one value: the symbolic constant identifying the source blend
function. See glBlendFunc.
GL_BLUE_BIAS
The params
parameter returns one value: the blue bias factor used during pixel transfers.
See glPixelTransfer.
GL_BLUE_BITS
The params
parameter returns one value: the number of blue bitplanes in each color buffer.
GL_BLUE_SCALE
The params
parameter returns one value: the blue scale factor used during pixel transfers.
See glPixelTransfer.
GL_CLIP_PLANEi
The params
parameter returns a single Boolean value indicating whether the specified
clipping plane is enabled. See glClipPlane.
GL_COLOR_CLEAR_VALUE
The params
parameter 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 value. See glClearColor.
GL_COLOR_MATERIAL
The params
parameter returns a single Boolean value indicating whether one or more
material parameters are tracking the current color. See glColorMaterial.
GL_COLOR_MATERIAL_FACE
The params
parameter returns one value: a symbolic constant indicating which materials
have a parameter that is tracking the current color. See glColorMaterial.
GL_COLOR_MATERIAL_PARAMETER
The params
parameter returns one value: a symbolic constant indicating which material
parameters are tracking the current color. See glColorMaterial.
GL_COLOR_WRITEMASK
The params
parameter returns four Boolean values: the red, green, blue, and alpha write enables
for the color buffers. See glColorMask.
GL_CULL_FACE
The params
parameter returns a single Boolean value indicating whether polygon culling is
enabled. See glCullFace.
GL_CULL_FACE_MODE
The params
parameter returns one value: a symbolic constant indicating which polygon faces
are to be culled. See glCullFace.
GL_CURRENT_COLOR
The params
parameter 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
The params
parameter returns one value: the current color index. See glIndex.
GL_CURRENT_NORMAL
The params
parameter 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
The params
parameter 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
The params
parameter returns one value: the distance from the eye to the current raster
position. See glRasterPos.
GL_CURRENT_RASTER_INDEX
The params
parameter returns one value: the color index of the current raster position.
See glRasterPos.
GL_CURRENT_RASTER_POSITION
The params
parameter returns four values: the x, y, z, and w
components of the current raster position. The x, y, and z
components are in window coordinates, and w is in clip coordinates. See glRasterPos.
GL_CURRENT_RASTER_TEXTURE_COORDS
The params
parameter returns four values: the s, t, r, and q current
raster texture coordinates. See glRasterPos and glTexCoordFFHXD1.
GL_CURRENT_RASTER_POSITION_VALID
The params
parameter returns a single Boolean value indicating whether the current raster
position is valid. See glRasterPos.
GL_CURRENT_TEXTURE_COORDS
The params
parameter returns four values: the s, t, r, and q
current texture coordinates. See glTexCoord.
GL_DEPTH_BIAS
The params
parameter returns one value: the depth bias factor used during pixel transfers.
See glPixelTransfer.
GL_DEPTH_BITS
The params
parameter returns one value: the number of bitplanes in the depth buffer.
GL_DEPTH_CLEAR_VALUE
The params
parameter 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
The params
parameter returns one value: the symbolic constant that indicates the depth
comparison function. See glDepthFunc.
GL_DEPTH_RANGE
The params
parameter 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
The params
parameter returns one value: the depth scale factor used during pixel
transfers. See glPixelTransfer.
GL_DEPTH_TEST
The params
parameter returns a single Boolean value indicating whether depth testing of
fragments is enabled. See glDepthFunc and glDepthRange.
GL_DEPTH_WRITEMASK
The params
parameter returns a single Boolean value indicating if the depth buffer is
enabled for writing. See glDepthMask.
GL_DITHER
The params
parameter returns a single Boolean value indicating whether dithering of
fragment colors and indexes is enabled.
GL_DOUBLEBUFFER
The params
parameter returns a single Boolean value indicating whether double buffering is
supported.
GL_DRAW_BUFFER
The params
parameter returns one value: a symbolic constant indicating which buffers are
being drawn to. See glDrawBuffer.
GL_EDGE_FLAG
The params
parameter returns a single Boolean value indicating whether the current edge
flag is true or false. See glEdgeFlag.
GL_FOG
The params
parameter returns a single Boolean value indicating whether fogging is enabled.
See glFog.
GL_FOG_COLOR
The params
parameter 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
The params
parameter returns one value: the fog density parameter. See glFog.
GL_FOG_END
The params
parameter returns one value: the end factor for the linear fog equation. See glFog.
GL_FOG_HINT
The params
parameter returns one value: a symbolic constant indicating the mode of the
fog hint. See glHint.
GL_FOG_INDEX
The params
parameter returns one value: the fog color index. See glFog.
GL_FOG_MODE
The params
parameter returns one value: a symbolic constant indicating which fog
equation is selected. See glFog.
GL_FOG_START
The params
parameter returns one value: the start factor for the linear fog equation.
See glFog.
GL_FRONT_FACE
The params
parameter returns one value: a symbolic constant indicating whether
clockwise or counterclockwise polygon winding is treated as front-facing. See glFrontFace.
GL_GREEN_BIAS
The params
parameter returns one value: the green bias factor used during pixel
transfers.
GL_GREEN_BITS
The params
parameter returns one value: the number of green bitplanes in each color
buffer.
GL_GREEN_SCALE
The params
parameter returns one value: the green scale factor used during pixel
transfers. See glPixelTransfer.
GL_INDEX_BITS
The params
parameter returns one value: the number of bitplanes in each color-index
buffer.
GL_INDEX_CLEAR_VALUE
The params
parameter returns one value: the color index used to clear the color-index
buffers. See glClearIndex.
GL_INDEX_MODE
The params
parameter returns a single Boolean value indicating whether OpenGL is in
color-index mode (TRUE) or RGBA mode (FALSE).
GL_INDEX_OFFSET
The params
parameter returns one value: the offset added to color and stencil indexes
during pixel transfers. See glPixelTransfer.
GL_INDEX_SHIFT
The params
parameter returns one value: the amount that color and stencil indexes are
shifted during pixel transfers. See glPixelTransfer.
GL_INDEX_WRITEMASK
The params
parameter returns one value: a mask indicating which bitplanes of each
color-index buffer can be written. See glIndexMask.
GL_LIGHTi
The params
parameter returns a single Boolean value indicating whether the specified
light is enabled. See glLight
and glLightModel.
GL_LIGHTING
The params
parameter returns a single Boolean value indicating whether lighting is
enabled. See glLightModel.
GL_LIGHT_MODEL_AMBIENT
The params
parameter 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
The params
parameter 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
The params
parameter 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
The params
parameter returns a single Boolean value indicating whether antialiasing of
lines is enabled. See glLineWidth.
GL_LINE_SMOOTH_HINT
The params
parameter returns one value: a symbolic constant indicating the mode of the
line antialiasing hint. See glHint.
GL_LINE_STIPPLE
The params
parameter returns a single Boolean value indicating whether stippling of
lines is enabled. See glLineStipple.
GL_LINE_STIPPLE_PATTERN
The params
parameter returns one value: the 16-bit line stipple pattern. See glLineStipple.
GL_LINE_STIPPLE_REPEAT
The params
parameter returns one value: the line stipple repeat factor. See glLineStipple.
GL_LINE_WIDTH
The params
parameter returns one value: the line width as specified with glLineWidth.
GL_LINE_WIDTH_GRANULARITY
The params
parameter returns one value: the width difference between adjacent
supported widths for antialiased lines. See glLineWidth.
GL_LINE_WIDTH_RANGE
The params
parameter returns two values: the smallest and largest supported widths for
antialiased lines. See glLineWidth.
GL_LIST_BASE
The params
parameter returns one value: the base offset added to all names in arrays
presented to glCallLists. See glListBase.
GL_LIST_INDEX
The params
parameter 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
The params
parameter returns one value: a symbolic constant indicating the
construction mode of the display list currently being constructed. See glNewList.
GL_LOGIC_OP
The params
parameter returns a single Boolean value indicating whether fragment
indexes are merged into the frame buffer using a logical operation. See glLogicOp.
GL_LOGIC_OP_MODE
The params
parameter returns one value: a symbolic constant indicating the selected
logic operational mode. See glLogicOp.
GL_MAP1_COLOR_4
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates colors. See glMap1.
GL_MAP1_GRID_DOMAIN
The params
parameter returns two values: the endpoints of the 1-D maps grid domain.
See glMapGrid.
GL_MAP1_GRID_SEGMENTS
The params
parameter returns one value: the number of partitions in the 1-D maps grid
domain. See glMapGrid.
GL_MAP1_INDEX
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates color indexes. See glMap1.
GL_MAP1_NORMAL
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates normals. See glMap1.
GL_MAP1_TEXTURE_COORD_1
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 1-D texture coordinates. See glMap1E5BV.H.
GL_MAP1_TEXTURE_COORD_2
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 2-D texture coordinates. See glMap1.
GL_MAP1_TEXTURE_COORD_3
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 3-D texture coordinates. See glMap1E5BV.H.
GL_MAP1_TEXTURE_COORD_4
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 4-D texture coordinates. See glMap1.
GL_MAP1_VERTEX_3
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 3-D vertex coordinates. See glMap1E5BV.H.
GL_MAP1_VERTEX_4
The params
parameter returns a single Boolean value indicating whether 1-D evaluation
generates 4-D vertex coordinates. See glMap1.
GL_MAP2_COLOR_4
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates colors. See glMap2.
GL_MAP2_GRID_DOMAIN
The params
parameter returns four values: the endpoints of the 2-D maps i and j
grid domains. See glMapGrid.
GL_MAP2_GRID_SEGMENTS
The params
parameter returns two values: the number of partitions in the 2-D maps i
and j grid domains. See glMapGrid.
GL_MAP2_INDEX
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates color indexes. See glMap2.
GL_MAP2_NORMAL
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates normals. See glMap2.
GL_MAP2_TEXTURE_COORD_1
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 1-D texture coordinates. See glMap2E5BV.I.
GL_MAP2_TEXTURE_COORD_2
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 2-D texture coordinates. See glMap2.
GL_MAP2_TEXTURE_COORD_3
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 3-D texture coordinates. See glMap2E5BV.I.
GL_MAP2_TEXTURE_COORD_4
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 4-D texture coordinates. See glMap2.
GL_MAP2_VERTEX_3
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 3-D vertex coordinates. See glMap2E5BV.I.
GL_MAP2_VERTEX_4
The params
parameter returns a single Boolean value indicating whether 2-D evaluation
generates 4-D vertex coordinates. See glMap2.
GL_MAP_COLOR
The params
parameter returns a single Boolean value indicating whether colors and
color indexes are to be replaced by table lookup during pixel transfers. See glPixelTransfer.
GL_MAP_STENCIL
The params
parameter returns a single Boolean value indicating whether stencil indexes
are to be replaced by table lookup during pixel transfers. See glPixelTransfer.
GL_MATRIX_MODE
The params
parameter returns one value: a symbolic constant indicating which matrix
stack is currently the target of all matrix operations. See glMatrixMode.
GL_MAX_ATTRIB_STACK_DEPTH
The params
parameter returns one value: the maximum supported depth of the attribute
stack. See glPushAttrib.
GL_MAX_CLIP_PLANES
The params
parameter returns one value: the maximum number of application-defined
clipping planes. See glClipPlane.
GL_MAX_EVAL_ORDER
The params
parameter returns one value: the maximum equation order supported by 1-D
and 2-D evaluators. See glMap1 and glMap2.
GL_MAX_LIGHTS
The params
parameter returns one value: the maximum number of lights. See glLight.
GL_MAX_LIST_NESTING
The params
parameter returns one value: the maximum recursion depth allowed during
display-list traversal. See glCallList.
GL_MAX_MODELVIEW_STACK_DEPTH
The params
parameter returns one value: the maximum supported depth of the modelview
matrix stack. See glPushMatrix.
GL_MAX_NAME_STACK_DEPTH
The params
parameter returns one value: the maximum supported depth of the selection
name stack. See glPushName.
GL_MAX_PIXEL_MAP_TABLE
The params
parameter returns one value: the maximum supported size of a glPixelMap
lookup table. See glPixelMap.
GL_MAX_PROJECTION_STACK_DEPTH
The params
parameter returns one value: the maximum supported depth of the projection
matrix stack. See glPushMatrix.
GL_MAX_TEXTURE_SIZE
The params
parameter returns one value: the maximum width or height of any texture
image (without borders). See glTexImage1D and glTexImage2D.
GL_MAX_TEXTURE_STACK_DEPTH
The params
parameter returns one value: the maximum supported depth of the texture
matrix stack. See glPushMatrix.
GL_MAX_VIEWPORT_DIMS
The params
parameter returns two values: the maximum supported width and height of the
viewport. See glViewport.
GL_MODELVIEW_MATRIX
The params
parameter returns 16 values: the modelview matrix on the top of the
modelview matrix stack. See glPushMatrix.
GL_MODELVIEW_STACK_DEPTH
The params
parameter returns one value: the number of matrices on the modelview matrix
stack. See glPushMatrix.
GL_NAME_STACK_DEPTH
The params
parameter returns one value: the number of names on the selection name
stack. See glPushMatrix.
GL_NORMALIZE
The params
parameter 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
The params
parameter returns one value: the byte alignment used for writing pixel data
to memory. See glPixelStore.
GL_PACK_LSB_FIRST
The params
parameter 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.
GL_PACK_ROW_LENGTH
The params
parameter returns one value: the row length used for writing pixel data to
memory. See glPixelStore.
GL_PACK_SKIP_PIXELS
The params
parameter returns one value: the number of pixel locations skipped before
the first pixel is written into memory. See glPixelStore.
GL_PACK_SKIP_ROWS
The params
parameter 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
The params
parameter returns a single Boolean value indicating whether the bytes of
2-byte and 4-byte pixel indexes and components are swapped before being written
to memory. See glPixelStore.
GL_PERSPECTIVE_CORRECTION_HINT
The params
parameter returns one value: a symbolic constant indicating the mode of the
perspective correction hint. See glHint.
GL_PIXEL_MAP_A_TO_A_SIZE
The params
parameter returns one value: the size of the alpha-to-alpha
pixel-translation table. See glPixelMap.
GL_PIXEL_MAP_B_TO_B_SIZE
The params
parameter returns one value: the size of the blue-to-blue pixel-translation
table. See glPixelMap.
GL_PIXEL_MAP_G_TO_G_SIZE
The params
parameter returns one value: the size of the green-to-green
pixel-translation table. See glPixelMap.
GL_PIXEL_MAP_I_TO_A_SIZE
The params
parameter returns one value: the size of the index-to-alpha pixel
translation table. See glPixelMap.
GL_PIXEL_MAP_I_TO_B_SIZE
The params
parameter returns one value: the size of the index-to-blue pixel
translation table. See glPixelMap.
GL_PIXEL_MAP_I_TO_G_SIZE
The params
parameter returns one value: the size of the index-to-green
pixel-translation table. See glPixelMap.
GL_PIXEL_MAP_I_TO_I_SIZE
The params
parameter returns one value: the size of the index-to-index
pixel-translation table. See glPixelMap.
GL_PIXEL_MAP_I_TO_R_SIZE
The params
parameter returns one value: the size of the index-to-red pixel-translation
table. See glPixelMap.
GL_PIXEL_MAP_R_TO_R_SIZE
The params
parameter returns one value: the size of the red-to-red pixel-translation
table. See glPixelMap.
GL_PIXEL_MAP_S_TO_S_SIZE
The params
parameter returns one value: the size of the stencil-to-stencil pixel
translation table. See glPixelMap.
GL_POINT_SIZE
The params
parameter returns one value: the point size as specified by glPointSize.
GL_POINT_SIZE_GRANULARITY
The params
parameter returns one value: the size difference between adjacent supported
sizes for antialiased points. See glPointSize.
GL_POINT_SIZE_RANGE
The params
parameter returns two values: the smallest and largest supported sizes for
antialiased points. See glPointSize.
GL_POINT_SMOOTH
The params
parameter returns a single Boolean value indicating whether antialiasing of
points is enabled. See glPointSize.
GL_POINT_SMOOTH_HINT
The params
parameter returns one value: a symbolic constant indicating the mode of the
point antialiasing hint. See glHint.
GL_POLYGON_MODE
The params
parameter 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_SMOOTH
The params
parameter returns a single Boolean value indicating whether antialiasing of
polygons is enabled. See glPolygonMode.
GL_POLYGON_SMOOTH_HINT
The params
parameter returns one value: a symbolic constant indicating the mode of the
polygon antialiasing hint. See glHint.
GL_POLYGON_STIPPLE
The params
parameter returns a single Boolean value indicating whether stippling of
polygons is enabled. See glPolygonStipple.
GL_PROJECTION_MATRIX
The params
parameter returns 16 values: the projection matrix on the top of the
projection matrix stack. See glPushMatrix.
GL_PROJECTION_STACK_DEPTH
The params
parameter returns one value: the number of matrices on the projection
matrix stack. See glPushMatrix.
GL_READ_BUFFER
The params
parameter returns one value: a symbolic constant indicating which color
buffer is selected for reading. See glReadPixels and glAccum.
GL_RED_BIAS
The params
parameter returns one value: the red bias factor used during pixel
transfers. See glPixelTransfer.
GL_RED_BITS
The params
parameter returns one value: the number of red bitplanes in each color
buffer.
GL_RED_SCALE
The params
parameter returns one value: the red scale factor used during pixel
transfers. See glPixelTransfer.
GL_RENDER_MODE
The params
parameter returns one value: a symbolic constant indicating whether OpenGL
is in render, select, or feedback mode. See glRenderMode.
GL_RGBA_MODE
The params
parameter returns a single Boolean value indicating whether OpenGL is in
RGBA mode (TRUE) or color-index mode (FALSE). See glColor.
GL_SCISSOR_BOX
The params
parameter returns four values: the x and y window coordinates
of the scissor box, followed by its width and height. See glScissor.
GL_SCISSOR_TEST
The params
parameter returns a single Boolean value indicating whether scissoring is
enabled. See glScissor.
GL_SHADE_MODEL
The params
parameter returns one value: a symbolic constant indicating whether the
shading mode is flat or smooth. See glShadeModel.
GL_STENCIL_BITS
The params
parameter returns one value: the number of bitplanes in the stencil buffer.
GL_STENCIL_CLEAR_VALUE
The params
parameter returns one value: the index to which the stencil bitplanes are
cleared. See glClearStencil.
GL_STENCIL_FAIL
The params
parameter returns one value: a symbolic constant indicating what action is
taken when the stencil test fails. See glStencilOp.
GL_STENCIL_FUNC
The params
parameter returns one value: a symbolic constant indicating what function
is used to compare the stencil reference value with the stencil buffer value.
See glStencilFunc.
GL_STENCIL_PASS_DEPTH_FAIL
The params
parameter 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
The params
parameter 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
The params
parameter returns one value: the reference value that is compared with the
contents of the stencil buffer. See glStencilFunc.
GL_STENCIL_TEST
The params
parameter returns a single Boolean value indicating whether stencil testing
of fragments is enabled. See glStencilFunc and glStencilOp.
GL_STENCIL_VALUE_MASK
The params
parameter 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
The params
parameter returns one value: the mask that controls writing of the stencil
bitplanes. See glStencilMask.
GL_STEREO
The params
parameter returns a single Boolean value indicating whether stereo buffers
(left and right) are supported.
GL_SUBPIXEL_BITS
The params
parameter 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
The params
parameter returns a single Boolean value indicating whether 1-D texture
mapping is enabled. See glTexImage1D.
GL_TEXTURE_2D
The params
parameter returns a single Boolean value indicating whether 2-D texture
mapping is enabled. See glTexImage2D.
GL_TEXTURE_ENV_COLOR
The params
parameter returns four values: the red, green, blue, and alpha values of
the texture environment 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 glTexEnv.
GL_TEXTURE_ENV_MODE
The params
parameter returns one value: a symbolic constant indicating which texture
environment function is currently selected. See glTexEnv.
GL_TEXTURE_GEN_S
The params
parameter returns a single Boolean value indicating whether automatic
generation of the S texture coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_T
The params
parameter returns a single Boolean value indicating whether automatic
generation of the T texture coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_R
The params
parameter returns a single Boolean value indicating whether automatic
generation of the R texture coordinate is enabled. See glTexGen.
GL_TEXTURE_GEN_Q
The params
parameter returns a single Boolean value indicating whether automatic
generation of the Q texture coordinate is enabled. See glTexGen.
GL_TEXTURE_MATRIX
The params
parameter returns 16 values: the texture matrix on the top of the texture
matrix stack. See glPushMatrix.
GL_TEXTURE_STACK_DEPTH
The params
parameter returns one value: the number of matrices on the texture matrix
stack. See glPushMatrix.
GL_UNPACK_ALIGNMENT
The params
parameter returns one value: the byte alignment used for reading pixel data
from memory. See glPixelStore.
GL_UNPACK_LSB_FIRST
The params
parameter 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
The params
parameter returns one value: the row length used for reading pixel data
from memory. See glPixelStore.
GL_UNPACK_SKIP_PIXELS
The params
parameter returns one value: the number of pixel locations skipped before
the first pixel is read from memory. See glPixelStore.
GL_UNPACK_SKIP_ROWS
The params
parameter 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
The params
parameter returns a single Boolean value indicating whether the bytes of
2-byte and 4-byte pixel indexes and components are swapped after being read
from memory. See glPixelStore.
GL_VIEWPORT
The params
parameter returns four values: the x and y window coordinates
of the viewport, followed by its width and height. See glViewport.
GL_ZOOM_X
The params
parameter returns one value: the x pixel zoom factor. See glPixelZoom.
GL_ZOOM_Y
The params
parameter returns one value: the y pixel zoom factor. See glPixelZoom.
params
Returns the
value or values of the specified parameter.
Remarks
These four
functions return values for simple state variables in OpenGL. The pname
parameter 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 from the state
variable value being requested. If you call glGetBooleanv, 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 you call glGetIntegerv,
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 you call glGetFloatv
or glGetDoublev, Boolean values are returned as GL_TRUE or GL_FALSE, and
integer values are converted to floating-point values.
You can query
many of the Boolean parameters more easily with glIsEnabled.
Error Codes
The following
are the error codes generated and their conditions.
|
Error
Code |
Condition |
|
GL_INVALID_ENUM
|
pname was not an accepted value. |
|
GL_INVALID_OPERATION
|
glGet was called between a call to glBegin and the
corresponding call to glEnd. |
See Also