glGetBooleanv, glGetDoublev, glGetFloatv, glGetIntegerv

These functions return the value or values of a selected parameter.

void glGetBooleanv(
  GLenum pname,        
  GLboolean * params   
);
 
void glGetDoublev(
  GLenum pname,       
  GLdouble * params   
);
 
void glGetFloatv(
  GLenum pname,      
  GLfloat * params   
);
 
void glGetIntegerv(
  GLenum pname,   
  GLint * params  
);

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 glTexCoord.
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 glMap1.
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 glMap1.
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 glMap1.
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 glMap2.
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 glMap2.
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 glMap2.
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.

QuickInfo

  Windows NT: Use version 3.5 and later.
  Windows: Use Windows 95 and later.
  Windows CE: Unsupported.
  Header: Declared in gl.h.
  Import Library: Link with opengl32.lib.

glGetBooleanv, glGetDoublev, glGetFloatv, glGetIntegerv

Parameters

Remarks

Error Codes

QuickInfo

See Also