Silicon Graphics

Appendix B
OpenGL State Variables

This appendix lists the queryable OpenGL state variables, their default values, and the commands for obtaining the values of these variables. It also describes OpenGL's error handling facility, and how to save and restore sets of state variables. The OpenGL Reference Manual contains detailed information on all the commands and constants discussed in this appendix. This appendix has these major sections:

The Query Commands

There are four commands for obtaining simple state variables, and one for determining whether a particular state is enabled or disabled.void glGetBooleanv(GLenum pname, GLboolean *params);
void glGetIntegerv(GLenum pname, GLint *params);
void glGetFloatv(GLenum pname, GLfloat *params);
void glGetDoublev(GLenum pname, GLdouble *params);

Obtains Boolean, integer, floating-point, or double-precision state variables. The pname argument is a symbolic constant indicating the state variable to return, and params is a pointer to an array of the indicated type in which to place the returned data. The possible values for pname are listed in the tables in "OpenGL State Variables." A type conversion is performed if necessary to return the desired variable as the requested data type.

GLboolean glIsEnabled(GLenum cap)

Returns GL_TRUE if the mode specified by cap is enabled; otherwise, returns GL_FALSE. The possible values for cap are listed in the tables in "OpenGL State Variables"

Other specialized commands return specific state variables. The prototypes for these commands are listed here; to find out when you need to use these commands, use the tables in "OpenGL State Variables" Also see the OpenGL Reference Manual. OpenGL's error handling facility and the glGetError() command are described in more detail in the next section.

void glGetClipPlane(GLenum plane, GLdouble *equation);

GLenum glGetError(void);

void glGetLight{if}v(GLenum light, GLenum pname, TYPE *params);

void glGetMap{ifd}v(GLenum target, GLenum query, TYPE *v);

void glGetMaterial{if}v(GLenum face, GLenum pname, TYPE *params);

void glGetPixelMap{f ui us}v(GLenum map, TYPE *values);

void glGetPolygonStipple(GLubyte *mask);

const GLubyte * glGetString(GLenum name);

void glGetTexEnv{if}v(GLenum target, GLenum pname, TYPE *params);

void glGetTexGen{ifd}v(GLenum coord, GLenum pname, TYPE *params);

void glGetTexImage(GLenum target, GLint level, GLenum format, GLenum type, GLvoid *pixels);

void glGetTexLevelParameter{if}v(GLenum target, GLint level, GLenum pname, TYPE *params);

void glGetTexParameter{if}v(GLenum target, GLenum pname, TYPE *params);

Error Handling

When OpenGL detects an error, it records a current error code. The command that caused the error is ignored, so it has no effect on OpenGL state or on the framebuffer contents. (If the error recorded was GL_OUT_OF_MEMORY, however, the results of the command are undefined.) Once recorded, the current error code isn't cleared - that is, additional errors aren't recorded - until you call the query command glGetError(), which returns the current error code. In distributed implementations of OpenGL, there might be multiple current error codes, each of which remains set until queried. Once you've queried all the current error codes, or if there's no error, glGetError() returns GL_NO_ERROR. Thus, if you obtain an error code, it's good practice to continue to call glGetError() until GL_NO_ERROR is returned to be sure you've discovered all the errors. Table B-1 lists the defined OpenGL error codes.

You can use the GLU routine gluErrorString() to obtain a descriptive string corresponding to the error code passed in. This routine is described in more detail in "Describing Errors." Note that GLU routines often return error values if an error is detected. Also, the GLU defines the error codes GLU_INVALID_ENUM, GLU_INVALID_VALUE, and GLU_OUT_OF_MEMORY, which have the same meaning as the related OpenGL codes.
Table B-1 : OpenGL Error Codes
Error Code Description
GL_INVALID_ENUM GLenum argument out of range
GL_INVALID_VALUE Numeric argument out of range
GL_INVALID_OPERATION Operation illegal in current state
GL_STACK_OVERFLOW Command would cause a stack overflow
GL_STACK_UNDERFLOW Command would cause a stack underflow
GL_OUT_OF_MEMORY Not enough memory left to execute command

 

Saving and Restoring Sets of State Variables

You can save and restore the values of a collection of state variables on an attribute stack with the commands glPushAttrib() and glPopAttrib(). The attribute stack has a depth of at least 16, and the actual depth can be obtained using GL_MAX_ATTRIB_STACK_DEPTH with glGetIntegerv(). Pushing a full stack or popping an empty one generates an error.

In general, it's faster to use glPushAttrib() and glPopAttrib() than to get and restore the values yourself. Some values might be pushed and popped in the hardware, and saving and restoring them might be expensive. Also, if you're operating on a remote client, all the attribute data has to be transferred across the network connection and back as it's saved and restored. However, your OpenGL implementation keeps the attribute stack on the server, avoiding unnecessary network delays. void glPushAttrib(GLbitfield mask);

Saves all the attributes indicated by bits in mask by pushing them onto the attribute stack. Table B-2 lists the possible mask bits that can be logically ORed together to save any combination of attributes. Each bit corresponds to a collection of individual state variables. For example, GL_LIGHTING_BIT refers to all the state variables related to lighting, which include the current material color, the ambient, diffuse, specular, and emitted light, a list of the lights that are enabled, and the directions of the spotlights. When glPopAttrib() is called, all those variables are restored. To find out exactly which attributes are saved for particular mask values, see the tables in "OpenGL State Variables."
Table B-2 : Attribute Groups
Mask Bit Attribute Group
GL_ACCUM_BUFFER_BIT accum-buffer
GL_ALL_ATTRIB_BITS --
GL_COLOR_BUFFER_BIT color-buffer
GL_CURRENT_BIT current
GL_DEPTH_BUFFER_BIT depth-buffer
GL_ENABLE_BIT enable
GL_EVAL_BIT eval
GL_FOG_BIT fog
GL_HINT_BIT hint
GL_LIGHTING_BIT  lighting
GL_LINE_BIT line
GL_LIST_BIT list
GL_PIXEL_MODE_BIT pixel
GL_POINT_BIT point
GL_POLYGON_BIT polygon
GL_POLYGON_STIPPLE_BIT polygon-stipple
GL_SCISSOR_BIT scissor
GL_STENCIL_BUFFER_BIT stencil-buffer
GL_TEXTURE_BIT texture
GL_TRANSFORM_BIT transform
GL_VIEWPORT_BIT  viewport

 

void glPopAttrib(void);

Restores the values of those state variables that were saved with the last glPushAttrib().

OpenGL State Variables

The following pages contain tables that list the names of queryable state variables. For each variable, the tables list a description of it, its attribute group, its initial or minimum value, and the suggested glGet*() command to use for obtaining it. State variables that can be obtained using glGetBooleanv(), glGetIntegerv(), glGetFloatv(), or glGetDoublev() are listed with just one of these commands - the one that's most appropriate given the type of data to be returned. These state variables can't be obtained using glIsEnabled(). However, state variables for which glIsEnabled() is listed as the query command can also be obtained using glGetBooleanv(), glGetIntegerv(), glGetFloatv(), and glGetDoublev(). State variables for which any other command is listed as the query command can be obtained only by using that command. If no attribute group is listed, the variable doesn't belong to any group. All queryable state variables except the implementation-dependent ones have initial values. If no initial value is listed, you need to consult the section where that variable is discussed (or the OpenGL Reference Manual) to determine its initial value.

Current Values and Associated Data

Table B-3 : State Variables for Current Values and Associated Data
State Variable Description Attribute Group Initial Value Get Command
GL_CURRENT_COLOR Current color current 1, 1, 1, 1 glGetIntegerv() , glGetFloatv()
GL_CURRENT_INDEX Current color index current 1 glGetIntegerv() , glGetFloatv()
GL_CURRENT_TEXTURE_COORDS Current texture coordinates current 0, 0, 0, 1 glGetFloatv()
GL_CURRENT_NORMAL Current normal current 0, 0, 1 glGetFloatv()
GL_CURRENT_RASTER_POSITION Current raster position current 0, 0, 0, 1 glGetFloatv()
 
 
 
GL_CURRENT_RASTER_DISTANCE Current raster distance current 0 glGetFloatv()
GL_CURRENT_RASTER_COLOR Color associated with raster position current 1, 1, 1, 1 glGetIntegerv() , glGetFloatv()
GL_CURRENT_RASTER_INDEX Color index associated with raster position current 1 glGetIntegerv() , glGetFloatv()
GL_CURRENT_RASTER_TEXTURE_ COORDS Texture coordinates associated with raster position current 0, 0, 0, 1 glGetFloatv()
GL_CURRENT_RASTER_POSITION_ VALID Raster position valid bit current GL_TRUE glGetBooleanv( )
GL_EDGE_FLAG Edge flag current GL_TRUE glGetBooleanv( )

 

Transformation

Table B-4 : Transformation State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_MODELVIEW_MATRIX Modelview matrix stack -- Identity glGetFloatv()
GL_PROJECTION_MATRIX Projection matrix stack -- Identity glGetFloatv()
GL_TEXTURE_MATRIX Texture matrix stack -- Identity glGetFloatv()
GL_VIEWPORT Viewport origin and extent viewport -- glGetIntegerv()
GL_DEPTH_RANGE Depth range near and far viewport 0, 1 glGetFloatv()
GL_MODELVIEW_STACK_DEPTH Modelview matrix stack pointer -- 1 glGetIntegerv()
GL_PROJECTION_STACK_DEPTH Projection matrix stack pointer -- 1 glGetIntegerv()
GL_TEXTURE_STACK_DEPTH Texture matrix stack pointer -- 1 glGetIntegerv()
GL_MATRIX_MODE Current matrix mode transform GL_MODELVI EW glGetIntegerv()
GL_NORMALIZE Current normal normalization on/off transform/ enable GL_FALSE glIsEnabled()
GL_CLIP_PLANEi User clipping plane coefficients transform 0, 0, 0, 0 glGetClipPlane()
GL_CLIP_PLANEi ith user clipping plane enabled transform/ enable GL_FALSE glIsEnabled()

 

Coloring

Table B-5 : Coloring State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_FOG_COLOR Fog color fog 0, 0, 0, 0 glGetFloatv()
GL_FOG_INDEX Fog index fog 0 glGetFloatv()
GL_FOG_DENSITY Exponential fog density fog 1.0 glGetFloatv()
GL_FOG_START Linear fog start fog 0.0 glGetFloatv()
GL_FOG_END Linear fog end fog 1.0 glGetFloatv()
GL_FOG_MODE Fog mode fog GL_EXP glGetIntegerv()
GL_FOG True if fog enabled fog/enable GL_FALSE glIsEnabled()
GL_SHADE_MODEL glShadeModel() setting lighting GL_SMOOTH glGetIntegerv()

 

Lighting

See also Table 6-1 and Table 6-2 for initial values.
Table B-6 : Lighting State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_LIGHTING True if lighting is enabled lighting /enable GL_FALSE glIsEnabled()
GL_COLOR_MATERIAL True if color tracking is enabled lighting GL_FALSE glIsEnabled()
GL_COLOR_MATERIAL_PARAME TER Material properties tracking current color lighting GL_AMBIENT_
AND_DIFFUSE		 glGetIntegerv()
GL_COLOR_MATERIAL_FACE Face(s) affected by color tracking lighting GL_FRONT_
AND_BACK		 glGetIntegerv()
GL_AMBIENT Ambient material color lighting (0.2, 0.2, 0.2, 1.0) glGetMaterialfv()
GL_DIFFUSE Diffuse material color lighting (0.8, 0.8, 0.8, 1.0) glGetMaterialfv()
GL_SPECULAR Specular material color lighting (0.0, 0.0, 0.0, 1.0) glGetMaterialfv()
GL_EMISSION Emissive material color lighting (0.0, 0.0, 0.0, 1.0) glGetMaterialfv()
GL_SHININESS Specular exponent of material lighting 0.0 glGetMaterialfv()
GL_LIGHT_MODEL_AMBIENT Ambient scene color lighting (0.2, 0.2, 0.2, 1.0) glGetFloatv()
GL_LIGHT_MODEL_LOCAL_VIE WER Viewer is local lighting GL_FALSE glGetBooleanv()
GL_LIGHT_MODEL_TWO_SIDE Use two-sided lighting lighting GL_FALSE glGetBooleanv()
GL_AMBIENT Ambient intensity of light i lighting (0.0,0.0,0.0,1.0) glGetLightfv()
GL_DIFFUSE Diffuse intensity of light i lighting -- glGetLightfv()
GL_SPECULAR Specular intensity of light i lighting -- glGetLightfv()
GL_POSITION Position of light i lighting (0.0, 0.0, 1.0, 0.0) glGetLightfv()
GL_CONSTANT_ATTENUATION Constant attenuation factor lighting 1.0 glGetLightfv()
GL_LINEAR_ATTENUATION Linear attenuation factor lighting 0.0 glGetLightfv()
GL_QUADRATIC_ATTENUATION Quadratic attenuation factor lighting 0.0 glGetLightfv()
GL_SPOT_DIRECTION Spotlight direction of light i lighting (0.0, 0.0, -1.0)
 
 
 		 glGetLightfv()
GL_SPOT_EXPONENT Spotlight exponent of light i lighting 0.0 glGetLightfv()
GL_SPOT_CUTOFF Spotlight angle of light i lighting 180.0 glGetLightfv()
GL_LIGHTi True if light i enabled lighting /enable GL_FALSE glIsEnabled()
GL_COLOR_INDEXES ca, cd, and cs for color-index lighting lighting /enable 0, 1, 1 glGetFloatv()

 

Rasterization

Table B-7 : Rasterization State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_POINT_SIZE Point size point 1.0 glGetFloatv()
GL_POINT_SMOOTH Point antialiasing on point/enable GL_FALSE glIsEnabled()
GL_LINE_WIDTH Line width line 1.0 glGetFloatv()
GL_LINE_SMOOTH Line antialiasing on line/enable GL_FALSE glIsEnabled()
GL_LINE_STIPPLE_PATTERN Line stipple line 1's glGetIntegerv()
GL_LINE_STIPPLE_REPEAT Line stipple repeat line 1 glGetIntegerv()
GL_LINE_STIPPLE Line stipple enable line/enable GL_FALSE glIsEnabled()
GL_CULL_FACE Polygon culling enabled polygon/enable GL_FALSE glIsEnabled()
GL_CULL_FACE_MODE Cull front-/back-facing polygons polygon GL_BACK glGetIntegerv()
GL_FRONT_FACE Polygon front-face CW/CCW indicator polygon GL_CCW glGetIntegerv()
GL_POLYGON_SMOOTH Polygon antialiasing on polygon/enable GL_FALSE glIsEnabled()
GL_POLYGON_MODE Polygon rasterization mode (front and back) polygon GL_FILL glGetIntegerv()
GL_POLYGON_STIPPLE Polygon stipple enable polygon/enable GL_FALSE glIsEnabled()
-- Polygon stipple pattern polygon-stipple 1's glGetPolygon-S tipple()

 

Texturing

Table B-8 : Texturing State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_TEXTURE_x True if x-D texturing enabled (x is 1D or 2D) texture/ enable GL_FALSE glIsEnabled()
GL_TEXTURE x-D texture image at level of detail i -- -- glGetTexImage()
GL_TEXTURE_WIDTH x-D texture image i's width -- 0 glGetTexLevelParameter()
GL_TEXTURE_HEIGHT x-D texture image i's height -- 0 glGetTexLevelParameter()
GL_TEXTURE_BORDER x-D texture image i's border width -- 0 glGetTexLevelParameter()
GL_TEXTURE_COMPONENTS Texture image components -- 1 glGetTexLevelParameter()
GL_TEXTURE_BORDER_COL OR Texture border color texture 0, 0, 0, 0 glGetTexParameter()
GL_TEXTURE_MIN_FILTER Texture minification function texture GL_NEAREST_ MIPMAP_LINEA R glGetTexParameter()
GL_TEXTURE_MAG_FILTER Texture magnification function texture GL_LINEAR glGetTexParameter()
GL_TEXTURE_WRAP_x Texture wrap mode (x is S or T) texture GL_REPEAT glGetTexParameter()
GL_TEXTURE_ENV_MODE Texture application function texture GL_MODULATE glGetTexEnviv()
GL_TEXTURE_ENV_COLOR Texture environment color texture 0, 0, 0, 0 glGetTexEnvfv()
GL_TEXTURE_GEN_x Texgen enabled (x is S, T, R, or Q) texture/ enable GL_FALSE glIsEnabled()
GL_EYE_LINEAR Texgen plane equation coefficients texture -- glGetTexGenfv()
GL_OBJECT_LINEAR Texgen object linear coefficients texture -- glGetTexGenfv()
GL_TEXTURE_GEN_MODE Function used for texgen texture GL_EYE_LINEA R glGetTexGeniv()

 

Pixel Operations

Table B-9 : Pixel Operations
State Variable Description Attribute Group Initial Value Get Command
GL_SCISSOR_TEST Scissoring enabled scissor/enable GL_FALSE glIsEnabled()
GL_SCISSOR_BOX Scissor box scissor -- glGetIntegerv()
GL_STENCIL_TEST Stenciling enabled stencil-buffer/ enable GL_FALSE glIsEnabled()
GL_STENCIL_FUNC Stencil function stencil-buffer GL_ALWAYS glGetIntegerv()
GL_STENCIL_VALUE_MASK Stencil mask stencil-buffer 1's glGetIntegerv()
GL_STENCIL_REF Stencil reference value stencil-buffer 0 glGetIntegerv()
GL_STENCIL_FAIL Stencil fail action stencil-buffer GL_KEEP glGetIntegerv()
GL_STENCIL_PASS_DEPTH_FAI L Stencil depth buffer fail action stencil-buffer GL_KEEP glGetIntegerv()
GL_STENCIL_PASS_DEPTH_PAS S Stencil depth buffer pass action stencil-buffer GL_KEEP glGetIntegerv()
GL_ALPHA_TEST Alpha test enabled color-buffer/e nable GL_FALSE glIsEnabled()
GL_ALPHA_TEST_FUNC Alpha test function color-buffer GL_ALWAYS glGetIntegerv()
GL_ALPHA_TEST_REF Alpha test reference value color-buffer 0 glGetIntegerv()
GL_DEPTH_TEST Depth buffer enabled depth-buffer/ enable GL_FALSE glIsEnabled()
GL_DEPTH_FUNC Depth buffer test function depth-buffer GL_LESS glGetIntegerv()
GL_BLEND Blending enabled color-buffer/e nable GL_FALSE glIsEnabled()
GL_BLEND_SRC Blending source function color-buffer GL_ONE glGetIntegerv()
GL_BLEND_DST Blending destination function color-buffer GL_ZERO glGetIntegerv()
GL_LOGIC_OP Logical operation enabled color-buffer/e nable GL_FALSE glIsEnabled()
GL_LOGIC_OP_MODE Logical operation function color-buffer GL_COPY glGetIntegerv()
GL_DITHER Dithering enabled color-buffer/e nable GL_TRUE glIsEnabled()

 

Framebuffer Control

Table B-10 : Framebuffer Control State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_DRAW_BUFFER Buffers selected for drawing color-buffer -- glGetIntegerv()
GL_INDEX_WRITEMASK Color-index writemask color-buffer 1's glGetIntegerv()
GL_COLOR_WRITEMASK Color write enables; R, G, B, or A color-buffer GL_TRUE glGetBooleanv()
GL_DEPTH_WRITEMASK Depth buffer enabled for writing depth-buffer GL_TRUE glGetBooleanv()
GL_STENCIL_WRITEMASK Stencil-buffer writemask stencil-buffer 1's glGetIntegerv()
GL_COLOR_CLEAR_VALUE Color-buffer clear value (RGBA mode) color-buffer 0, 0, 0, 0 glGetFloatv()
GL_INDEX_CLEAR_VALUE Color-buffer clear value (color-index mode) color-buffer 0 glGetFloatv()
GL_DEPTH_CLEAR_VALUE Depth-buffer clear value depth-buffer 1 glGetIntegerv()
GL_STENCIL_CLEAR_VALUE Stencil-buffer clear value stencil-buffer 0 glGetIntegerv()
GL_ACCUM_CLEAR_VALUE Accumulation-buffer clear value accum-buffer 0 glGetFloatv()

 

Pixels

Table B-11 : Pixel State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_UNPACK_SWAP_BYTES Value of GL_UNPACK_SWAP_BYTES -- GL_FALSE glGetBooleanv()
GL_UNPACK_LSB_FIRST Value of GL_UNPACK_LSB_FIRST -- GL_FALSE glGetBooleanv()
GL_UNPACK_ROW_LENGTH Value of GL_UNPACK_ROW_LENGT H -- 0 glGetIntegerv()
GL_UNPACK_SKIP_ROWS Value of GL_UNPACK_SKIP_ROWS -- 0 glGetIntegerv()
GL_UNPACK_SKIP_PIXELS Value of GL_UNPACK_SKIP_PIXELS -- 0 glGetIntegerv()
GL_UNPACK_ALIGNMENT Value of GL_UNPACK_ALIGNMENT -- 4 glGetIntegerv()
GL_PACK_SWAP_BYTES Value of GL_PACK_SWAP_BYTES -- GL_FALSE glGetBooleanv()
GL_PACK_LSB_FIRST Value of GL_PACK_LSB_FIRST -- GL_FALSE glGetBooleanv()
GL_PACK_ROW_LENGTH Value of GL_PACK_ROW_LENGTH -- 0 glGetIntegerv()
GL_PACK_SKIP_ROWS Value of GL_PACK_SKIP_ROWS -- 0 glGetIntegerv()
GL_PACK_SKIP_PIXELS Value of GL_PACK_SKIP_PIXELS -- 0 glGetIntegerv()
GL_PACK_ALIGNMENT Value of GL_PACK_ALIGNMENT -- 4 glGetIntegerv()
GL_MAP_COLOR True if colors are mapped pixel GL_FALSE glGetBooleanv()
GL_MAP_STENCIL True if stencil values are mapped pixel GL_FALSE glGetBooleanv()
GL_INDEX_SHIFT Value of GL_INDEX_SHIFT pixel 0 glGetIntegerv()
GL_INDEX_OFFSET Value of GL_INDEX_OFFSET pixel 0 glGetIntegerv()
GL_x_SCALE Value of GL_x_SCALE; x is GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, or GL_DEPTH pixel 1 glGetFloatv()
GL_x_BIAS Value of GL_x_BIAS; x is one of GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, or GL_DEPTH pixel 0 glGetFloatv()
GL_ZOOM_X x zoom factor pixel 1.0 glGetFloatv()
GL_ZOOM_Y y zoom factor pixel 1.0 glGetFloatv()
GL_x glPixelMap() translation tables; x is a map name from Table 8-5 pixel 0's glGetPixelMap()
GL_x_SIZE Size of table x pixel 1 glGetIntegerv()
GL_READ_BUFFER Read source buffer pixel -- glGetIntegerv()

 

Evaluators

Table B-12 : Evaluator State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_ORDER 1D map order -- 1 glGetMapiv()
GL_ORDER 2D map orders -- 1, 1 glGetMapiv()
GL_COEFF 1D control points -- -- glGetMapfv()
GL_COEFF 2D control points -- -- glGetMapfv()
GL_DOMAIN 1D domain endpoints -- -- glGetMapfv()
GL_DOMAIN 2D domain endpoints -- -- glGetMapfv()
GL_MAP1_x 1D map enables: x is map type eval/enable GL_FALSE glIsEnabled()
GL_MAP2_x 2D map enables: x is map type eval/enable GL_FALSE glIsEnabled()
GL_MAP1_GRID_DOMAIN 1D grid endpoints eval 0, 1 glGetFloatv()
GL_MAP2_GRID_DOMAIN 2D grid endpoints eval 0, 1; 0, 1 glGetFloatv()
GL_MAP1_GRID_SEGMENTS 1D grid divisions eval 1 glGetFloatv()
GL_MAP2_GRID_SEGMENTS 2D grid divisions eval 1,1 glGetFloatv()
GL_AUTO_NORMAL True if automatic normal generation enabled eval GL_FALSE glIsEnabled()

 

Hints

Table B-13 : Hint State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_PERSPECTIVE_CORRECTION_ HINT Perspective correction hint hint GL_DONT_CARE glGetIntegerv()
GL_POINT_SMOOTH_HINT Point smooth hint hint GL_DONT_CARE glGetIntegerv()
GL_LINE_SMOOTH_HINT Line smooth hint hint GL_DONT_CARE glGetIntegerv()
GL_POLYGON_SMOOTH_HINT Polygon smooth hint hint GL_DONT_CARE glGetIntegerv()
GL_FOG_HINT Fog hint hint GL_DONT_CARE glGetIntegerv()

 

Implementation-Dependent Values

Table B-14 : Implementation-Dependent State Variables
State Variable Description Attribute Group Minimum Value Get Command
GL_MAX_LIGHTS Maximum number of lights -- 8 glGetIntegerv()
GL_MAX_CLIP_PLANES Maximum number of user clipping planes -- 6 glGetIntegerv()
GL_MAX_MODELVIEW_STACK_ DEPTH Maximum modelview-matrix stack depth -- 32 glGetIntegerv()
GL_MAX_PROJECTION_STACK_ DEPTH Maximum projection-matrix stack depth -- 2 glGetIntegerv()
GL_MAX_TEXTURE_STACK_DE PTH Maximum depth of texture matrix stack -- 2 glGetIntegerv()
GL_SUBPIXEL_BITS Number of bits of subpixel precision in x and y -- 4 glGetIntegerv()
GL_MAX_TEXTURE_SIZE Maximum height or width of a texture image (w/o borders) -- 64 glGetIntegerv()
GL_MAX_PIXEL_MAP_TABLE Maximum size of a glPixelMap() translation table -- 32 glGetIntegerv()
GL_MAX_NAME_STACK_DEPT H Maximum selection-name stack depth -- 64 glGetIntegerv()
GL_MAX_LIST_NESTING Maximum display-list call nesting -- 64 glGetIntegerv()
GL_MAX_EVAL_ORDER Maximum evaluator polynomial order -- 8 glGetIntegerv()
GL_MAX_VIEWPORT_DIMS Maximum viewport dimensions -- -- glGetIntegerv()
GL_MAX_ATTRIB_STACK_DEPT H Maximum depth of the attribute stack -- 16 glGetIntegerv()
GL_AUX_BUFFERS Number of auxiliary buffers -- 0 glGetBooleanv( )
GL_RGBA_MODE True if color buffers store RGBA -- -- glGetBooleanv( )
GL_INDEX_MODE True if color buffers store indices -- -- glGetBooleanv( )
GL_DOUBLEBUFFER True if front & back buffers exist -- -- glGetBooleanv( )
GL_STEREO True if left & right buffers exist -- -- glGetFloatv()
GL_POINT_SIZE_RANGE Range (low to high) of antialiased point sizes -- 1, 1 glGetFloatv()
GL_POINT_SIZE_GRANULARIT Y Antialiased point-size granularity -- -- glGetFloatv()
GL_LINE_WIDTH_RANGE Range (low to high) of antialiased line widths -- 1, 1 glGetFloatv()
GL_LINE_WIDTH_GRANULARI TY Antialiased line-width granularity -- -- glGetFloatv()

 

Implementation-Dependent Pixel Depths

Table B-15 : Implementation-Dependent Pixel-Depth State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_RED_BITS Number of bits per red component in color buffers -- -- glGetIntegerv()
GL_GREEN_BITS Number of bits per green component in color buffers -- -- glGetIntegerv()
GL_BLUE_BITS Number of bits per blue component in color buffers -- -- glGetIntegerv()
GL_ALPHA_BITS Number of bits per alpha component in color buffers -- -- glGetIntegerv()
GL_INDEX_BITS Number of bits per index in color buffers -- -- glGetIntegerv()
GL_DEPTH_BITS Number of depth-buffer bitplanes -- -- glGetIntegerv()
GL_STENCIL_BITS Number of stencil bitplanes -- -- glGetIntegerv()
GL_ACCUM_RED_BITS Number of bits per red component in the accumulation buffer -- -- glGetIntegerv()
GL_ACCUM_GREEN_BITS Number of bits per green component in the accumulation buffer  -- -- glGetIntegerv()
GL_ACCUM_BLUE_BITS Number of bits per blue component in the accumulation buffer -- -- glGetIntegerv()
GL_ACCUM_ALPHA_BITS Number of bits per alpha component in the accumulation buffer -- -- glGetIntegerv()

 

Miscellaneous

Table B-16 : Miscellaneous State Variables
State Variable Description Attribute Group Initial Value Get Command
GL_LIST_BASE Setting of glListBase() list 0 glGetIntegerv()
GL_LIST_INDEX Number of display list under construction; 
0 if none		 -- 0 glGetIntegerv()
GL_LIST_MODE Mode of display list under construction; undefined if none -- 0 glGetIntegerv() 
GL_ATTRIB_STACK_DEPTH Attribute stack pointer -- 0 glGetIntegerv()
GL_NAME_STACK_DEPTH Name stack depth -- 0 glGetIntegerv()
GL_RENDER_MODE glRenderMode() setting -- GL_RENDER glGetIntegerv()
-- Current error code(s) -- 0 glGetError()

 

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