glGet
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 0.0 (or 0). 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.
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.
- GL_AUTO_NORMAL
-
params returns a single Boolean value indicating
whether 2D 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_DST_ALPHA_EXT
-
params returns one value, the symbolic constant
identifying the destination blend function for alpha.
See glBlendFuncSeparateEXT.
- GL_BLEND_DST_RGB_EXT
-
params returns one value, the symbolic constant
identifying the destination blend function for red, green, and blue.
See glBlendFuncSeparateEXT.
- 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_SRC_ALPHA_EXT
-
params returns one value, the symbolic constant
identifying the source blend function for alpha.
See glBlendFuncSeparateEXT.
- GL_BLEND_SRC_RGB_EXT
-
params returns one value, the symbolic constant
identifying the source blend function for red, green, and blue.
See glBlendFuncSeparateEXT.
- 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
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_EXT
-
params returns sixteen values: the color matrix
on the top of the color matrix stack.
See glPushMatrix and
glPixelTransfer.
- GL_COLOR_MATRIX_STACK_DEPTH_EXT
-
params returns one value, the maximum supported
depth of the color matrix stack.
See glPushMatrix and
glPixelTransfer.
- GL_COLOR_TABLE_EXT
-
params returns a single Boolean value indicating
whether colors are passed through a lookup table
before being used by convolution.
See glColorTableEXT.
- 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.
- 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. glRasterPos.
- GL_CURRENT_RASTER_TEXTURE_COORDS
-
params returns four values: the s,
t, r, and q current raster
texture coordinates. See
glRasterPos and
glTexCoord.
- 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_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_EXT
-
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_EXT. See glFog and
glFogFuncEXT.
- GL_FOG_FUNC_POINTS_EXT
-
params returns one value, the number of points
in the current custom fog blending function.
See glFog and
glFogFuncEXT.
- 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_EXT
-
params returns a single Boolean value indicating
whether fog offset is enabled. See glFog.
- GL_FOG_OFFSET_VALUE_EXT
-
params returns four values, a reference point
(x, y, z) in eye
coordinates, and an 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_GENERATE_MIPMAP_HINT_EXT
-
params returns one value, a symbolic constant
indicating the mode of the mipmap generation hint. See
glHint.
- 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_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 (GL_TRUE) or
RGBA mode (GL_FALSE).
- 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_EXT
-
params returns a single Boolean value indicating
whether pixel draw and copy operations
skip every other line in the destination pixel
array. See glCopyPixels and
glDrawPixels.
- GL_INTERLACE_READ_I3D
-
params returns a single Boolean value indicating
whether pixel read and copy operations
skip every other line in the destination pixel
array. See glReadPixels and
glCopyPixels.
- 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.
- LIGHT_MODEL_COLOR_CONTROL
-
params returns a single value indicating the
color control 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.
- 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
frame buffer 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.
- GL_MAP1_GRID_DOMAIN
-
params returns two values: the endpoints of the
1D map's grid domain. See glMapGrid.
- GL_MAP1_GRID_SEGMENTS
-
params returns one value, the number of
partitions in the 1D 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 2D map's i and j grid domains. See
glMapGrid.
- GL_MAP2_GRID_SEGMENTS
-
params returns two values: the number of
partitions in the 2D map's i and j grid
domains. See glMapGrid.
- 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_EXT
-
params returns one value, the maximum width,
height, or depth of any texture image (without
borders). See glTexImage3DEXT.
- GL_MAX_ATTRIB_STACK_DEPTH
-
is currently the
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_COLOR_MATRIX_STACK_DEPTH_EXT
-
params returns one value, the maximum supported
depth of the color matrix stack. See
glPushMatrix and
glPixelTransfer.
- GL_MAX_ELEMENTS_INDICES
-
params returns one value, the recommended maximum
number of indices that can efficiently be handled by
glDrawRangeElementsEXT.
- GL_MAX_ELEMENTS_VERTICES
-
params returns one value, the recommended maximum
number of vertices that can efficiently be handled by
glDrawRangeElementsEXT.
- GL_MAX_EVAL_ORDER
-
params returns one value, the maximum equation
order supported by 1D and 2D evaluators. See
glMap1 and
glMap2.
- GL_MAX_FOG_FUNC_POINTS_EXT
-
params returns one value, the maximum number of
control points supported in custom fog blending
functions. See glFog and
glFogFuncEXT.
- 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.
- 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_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_EXT
-
params returns a single Boolean value indicating
whether multisampling is enabled. See glEnable.
- 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_OCCLUSION_TEST_EXT
-
params returns a single Boolean value indicating whether
the occlusion test is enabled. See glEnable.
- GL_OCCLUSION_TEST_RESULT_EXT
-
params returns a single Boolean value indicating the result
of the occlusion test. A value of GL_TRUE indicates that a depth test
passed; therefore, the object must be rendered.
See glEnable.
- 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.
- 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.
- 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_PIXEL_TEX_GEN_EXT
-
params returns a single Boolean value indicating whether
pixel texture generation is enabled. See glEnable.
- GL_PIXEL_TEX_GEN_MODE_EXT
-
params returns one value, the pixel texture generation mode
as specified by glPixelTexGenEXT.
- 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
-
params returns a single Boolean value indicating
whether polygon offset is enabled. See
glPolygonOffset.
- GL_POLYGON_OFFSET_BIAS
-
params returns one value, the constant which is
added to the z value of each fragment generated
when a polygon is rasterized. See
glPolygonOffset.
- GL_POLYGON_OFFSET_FACTOR
-
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
glPolygonOffset.
- 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_EXT
-
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_EXT
-
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_EXT
-
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_EXT
-
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_EXT
-
params returns a single Boolean value indicating
whether colors are passed through a lookup table
after begin processed by the color matrix
operation. See glColorTableEXT.
- GL_POST_COLOR_MATRIX_GREEN_BIAS_EXT
-
params returns a single value, the bias term to
be added to green immediately after
multiplication by the top of the color matrix
stack. See glPixelTransfer.
- GL_POST_COLOR_MATRIX_GREEN_SCALE_EXT
-
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_EXT
-
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_EXT
-
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_EXT
-
params returns a single Boolean value indicating
whether colors are passed through a lookup table
before being processed by the color matrix
operation. See glColorTableEXT.
- 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_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.
- 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_RENDER_MODE
-
params returns one value, a symbolic constant
indicating whether the GL is in render, select,
or feedback mode. See glRenderMode.
- GL_RESCALE_NORMAL_EXT
-
params returns a single Boolean value indicating whether
rescale normal is enabled. See glEnable.
- 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_EXT
-
params returns a single Boolean value indicating whether
fragment alpha values will modify the multisampling fragment mask.
See glEnable.
- GL_SAMPLE_ALPHA_TO_ONE_EXT
-
params returns a single Boolean value indicating
whether fragment alpha will be set to the maximum possible
alpha value. See glEnable.
- GL_SAMPLE_BUFFERS_EXT
-
params returns one value, the number of multisample
buffers.
- GL_SAMPLE_MASK_INVERT_EXT
-
params returns a single Boolean value indicating
whether the temporary mask generated from the value of
GL_SAMPLE_MASK_VALUE_EXT will be inverted before it is
ANDed with the multisampling fragment mask. See
glSampleMaskEXT.
- GL_SAMPLE_MASK_EXT
-
params returns a single Boolean value indicating
whether the multisampling fragment mask will be
modified by a coverage mask. See
glSampleMaskEXT.
- GL_SAMPLE_MASK_VALUE_EXT
-
params returns one value, the coverage of the
multisampling fragment modification mask. See
glSampleMaskEXT.
- GL_SAMPLE_PATTERN_EXT
-
params returns one value, a symbolic constant
indicating the multisampling pattern. See
glSamplePatternEXT.
- GL_SAMPLES_EXT
-
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
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_2D
-
params returns a single Boolean value indicating
whether 2D texture mapping is enabled. See
glTexImage2D.
- GL_TEXTURE_3D_EXT
-
params returns a single Boolean value indicating
whether 3D texture mapping is enabled. See
glTexImage3DEXT.
- GL_TEXTURE_BINDING_1D
-
params returns a single value, the name of the
texture currently bound to the target
GL_TEXTURE_1D. See glBindTexture.
- GL_TEXTURE_BINDING_2D
-
params returns a single value, the name of the
texture currently bound to the target
GL_TEXTURE_2D. See glBindTexture.
- 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 glBindTexture.
- GL_TEXTURE_COLOR_TABLE_EXT
-
params returns a single Boolean value indicating
whether the texture color table is enabled. See
glColorTableEXT.
- 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.
- 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_EXT
-
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.
EXTENSIONS
Some routines and constants for this function are part of an extension, not part of the
core GL command set. The following extension names must be present in the string returned by
glGetString when called with argument GL_EXTENSIONS
to use these routines and constants.
- GL_EXT_blend_color
-
GL_BLEND_COLOR_EXT
is part of the EXT_blend_color extension.
- GL_EXT_blend_func_separate
-
GL_BLEND_DST_ALPHA_EXT, GL_BLEND_DST_RGB_EXT,
GL_BLEND_SRC_ALPHA_EXT and GL_BLEND_SRC_RGB_EXT
are part of the EXT_blend_func_separate extension.
- GL_EXT_blend_minmax
-
GL_BLEND_EQUATION_EXT
is part of the EXT_blend_minmax extension.
- GL_EXT_color_matrix
-
GL_COLOR_MATRIX_EXT, GL_COLOR_MATRIX_STACK_DEPTH_EXT,
GL_MAX_COLOR_MATRIX_STACK_DEPTH_EXT, GL_POST_COLOR_MATRIX_ALPHA_BIAS_EXT,
GL_POST_COLOR_MATRIX_ALPHA_SCALE_EXT, GL_POST_COLOR_MATRIX_BLUE_BIAS_EXT,
GL_POST_COLOR_MATRIX_BLUE_SCALE_EXT, GL_POST_COLOR_MATRIX_COLOR_TABLE_EXT,
GL_POST_COLOR_MATRIX_GREEN_BIAS_EXT, GL_POST_COLOR_MATRIX_GREEN_SCALE_EXT,
GL_POST_COLOR_MATRIX_RED_BIAS_EXT, and GL_POST_COLOR_MATRIX_RED_SCALE_EXT
are part of the EXT_color_matrix extension.
- GL_EXT_color_table
-
GL_COLOR_TABLE_EXT, GL_POST_CONVOLUTION_COLOR_TABLE_EXT, and
GL_POST_COLOR_MATRIX_COLOR_TABLE_EXT
are part of the EXT_color_table extension.
- GL_EXT_convolution
-
GL_CONVOLUTION_1D_EXT, GL_CONVOLUTION_2D_EXT, GL_SEPARABLE_2D_EXT,
GL_POST_CONVOLUTION_ALPHA_BIAS_EXT, GL_POST_CONVOLUTION_ALPHA_SCALE_EXT,
GL_POST_CONVOLUTION_BLUE_BIAS_EXT, GL_POST_CONVOLUTION_BLUE_SCALE_EXT,
GL_POST_CONVOLUTION_GREEN_BIAS_EXT, GL_POST_CONVOLUTION_GREEN_SCALE_EXT,
GL_POST_CONVOLUTION_RED_BIAS_EXT, and GL_POST_CONVOLUTION_RED_SCALE_EXT
are part of the EXT_convolution extension.
- GL_EXT_draw_range_elements
- GL_MAX_ELEMENTS_VERTICES_EXT and GL_MAX_ELEMENTS_INDICES_EXT
are part of the EXT_draw_range_elements extension.
- GL_EXT_fog_function
-
GL_FOG_FUNC_EXT, GL_FOG_FUNC_POINTS_EXT, and GL_MAX_FOG_FUNC_POINTS_EXT
are part of the EXT_fog_function extension.
- GL_EXT_fog_offset
-
GL_FOG_OFFSET_EXT and GL_FOG_OFFSET_VALUE_EXT
are part of the EXT_fog_offset extension.
- GL_EXT_generate_mipmap
-
GL_GENERATE_MIPMAP_HINT_EXT
is part of the EXT_generate_mipmap extension.
- EXT_interlace
-
GL_INTERLACE_EXT
is part of the EXT_interlace extension.
- EXT_interlace_read
- GL_INTERLACE_READ_I3D is part of the EXT_interlace_read
extension.
- GL_EXT_multisample
-
GL_MULTISAMPLE_EXT, GL_SAMPLE_ALPHA_TO_MASK_EXT, GL_SAMPLE_ALPHA_TO_ONE_EXT,
GL_SAMPLE_BUFFERS_EXT, GL_SAMPLE_MASK_INVERT_EXT, GL_SAMPLE_MASK_EXT,
GL_SAMPLE_MASK_VALUE_EXT, GL_SAMPLE_PATTERN_EXT, and GL_SAMPLES_EXT
are part of the EXT_multisample extension.
- GL_EXT_occlusion_test
-
GL_OCCLUSION_TEST_EXT and GL_OCCLUSION_TEST_RESULT_EXT
are part of the EXT_occlusion_test extension.
- GL_EXT_pixel_texture
-
GL_PIXEL_TEX_GEN_EXT and GL_PIXEL_TEX_GEN_MODE_EXT
are part of the EXT_pixel_texture extension.
- GL_EXT_rescale_normal
-
GL_RESCALE_NORMAL_EXT
is part of the EXT_rescale_normal extension.
- GL_EXT_separate_specular_color
-
GL_LIGHT_MODEL_COLOR_CONTROL_EXT
is part of the EXT_separate_specular_color extension.
- GL_EXT_texture3D
-
GL_TEXTURE_3D_EXT, GL_TEXTURE_3D_BINDING_EXT,
GL_MAX_3D_TEXTURE_SIZE_EXT, GL_PACK_IMAGE_HEIGHT_EXT,
GL_PACK_SKIP_IMAGES_EXT, and GL_UNPACK_IMAGE_HEIGHT_EXT
are part of the EXT_texture3D extension.
- GL_EXT_texture_color_table
- GL_TEXTURE_COLOR_TABLE_EXT is part of the EXT_texture_color_table
extension.
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.
SEE ALSO
glGetError,
glGetString