glGet

NAME

glGetBooleanv, glGetDoublev, glGetFloatv, glGetIntegerv -- return the value or values of a selected parameter

C SPECIFICATION

glGetBooleanv(GLenum pname,
              GLboolean *params)
glGetDoublev(GLenum pname,
             GLdouble *params)
glGetFloatv(GLenum pname,
            GLfloat *params)
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.

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_BIT
params returns one value, the number of blue bitplanes in the accumulation buffer.

GL_ACCUM_CLEAR_VALUE
params returns four values: the red, greeen, 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 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_DST
params returns one value, the symbolic constant identifying the destination blend function. See glBlendFunc.

GL_BLEND_SRC
params returns one value, the symbolic constant identifying the source blend function. 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 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_WRITEMASK
params returns four Boolean values: the red, green, blue, and alpha write enables for the color buffers. See glColorMask.

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_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.

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_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_WRITEMASK
params returns a single Boolean value indicating if the depth buffer is enabled for writing. See glDepthMask.

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_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_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_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).

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_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.

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.

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.

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_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_EVAL_ORDER
params returns one value, the maximum equation order supported by 1-D and 2-D evaluators. See glMap1 and glMap2.

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_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_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_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_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_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_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_SMOOTH
params returns a single Boolean value indicating whether antialiasing of polygons is enabled. See glPolygonMode.

GL_POLYGON_STIPPLE
params returns a single Boolean value indicating whether stippling of polygons is enabled. See glPolygonStipple.

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_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_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_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. See 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_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_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 called between a call to glBegin and the corresponding call to glEnd.

SEE ALSO

glGetClipPlane, glGetError, glGetLight, glGetMap, glGetMaterial, glGetPixelMap, glGetPolygonStipple, glGetString, glGetTexEnv, glGetTexGen, glGetTexImage, glGetTexLevelParameter, glGetTexParameter, glIsEnabled


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© 1995 Uwe Behrens. All rights reserved.