GLGET() MachTen Programmer’s Manual 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 )

delim $$

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 vari-
ables 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 glGet-
Integerv 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 nor-
mals, 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 val-
ues used to clear the accumula-
tion buffer. Integer values, if
requested, are linearly mapped
from the internal floating-point
representation such that 1.0
returns the most positive repre-
sentable integer value, and -1.0
returns the most negative repre-
sentable integer value. The ini-
tial value is (0, 0, 0, 0). 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. The initial
value is 0. 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. The initial
value is 1. See glPixelTransfer.

GL_ALPHA_TEST params returns a single boolean
value indicating whether alpha
testing of fragments is enabled.
The initial value is GL_FALSE.
See glAlphaFunc.

GL_ALPHA_TEST_FUNC params returns one value, the
symbolic name of the alpha test
function. The initial value is
GL_ALWAYS. See glAlphaFunc.

GL_ALPHA_TEST_REF params returns one value, the
reference value for the alpha
test. The initial value is 0.
See glAlphaFunc. An integer
value, if requested, is linearly
mapped from the internal float-
ing-point representation such
that 1.0 returns the most posi-
tive representable integer value,
and -1.0 returns the most nega-
tive representable integer value.

GL_ATTRIB_STACK_DEPTH params returns one value, the
depth of the attribute stack. If
the stack is empty, 0 is
returned. The initial value is 0.
See glPushAttrib.

GL_AUTO_NORMAL params returns a single boolean
value indicating whether 2D map
evaluation automatically gener-
ates surface normals. The initial
value is GL_FALSE. See glMap2.

GL_AUX_BUFFERS params returns one value, the
number of auxiliary color
buffers. The initial value is 0.

GL_BLEND params returns a single boolean
value indicating whether blending
is enabled. The initial value is
GL_FALSE. See glBlendFunc.

GL_BLEND_COLOR_EXT params returns four values, the
red, green, blue, and alpha val-
ues which are the components of
the blend color. See glBlendCol-
orEXT.

GL_BLEND_DST params returns one value, the
symbolic constant identifying the
destination blend function. The
initial value is GL_ZERO. See
glBlendFunc.

GL_BLEND_EQUATION_EXT params returns one value, a sym-
bolic constant indicating whether
the blend equation is
GL_FUNC_ADD_EXT, GL_MIN_EXT or
GL_MAX_EXT. See glBlendEqua-
tionEXT.

GL_BLEND_SRC params returns one value, the
symbolic constant identifying the
source blend function. The ini-
tial value is GL_ONE. See
glBlendFunc.

GL_BLUE_BIAS params returns one value, the
blue bias factor used during
pixel transfers. The initial
value is 0. 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. The initial
value is 1. See glPixelTransfer.

GL_CLIENT_ATTRIB_STACK_DEPTH
params returns one value indicat-
ing the depth of the attribute
stack. The initial value is 0.
See glPushClientAttrib.

GL_CLIP_PLANEi params returns a single boolean
value indicating whether the
specified clipping plane is
enabled. The initial value is
GL_FALSE. See glClipPlane.

GL_COLOR_ARRAY params returns a single boolean
value indicating whether the
color array is enabled. The ini-
tial value is GL_FALSE. See
glColorPointer.

GL_COLOR_ARRAY_SIZE params returns one value, the
number of components per color in
the color array. The initial
value is 4. See glColorPointer.

GL_COLOR_ARRAY_STRIDE params returns one value, the
byte offset between consecutive
colors in the color array. The
initial value is 0. See glColor-
Pointer.

GL_COLOR_ARRAY_TYPE params returns one value, the
data type of each component in
the color array. The initial
value is GL_FLOAT. See glColor-
Pointer.

GL_COLOR_CLEAR_VALUE params returns four values: the
red, green, blue, and alpha val-
ues 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 repre-
sentable integer value, and -1.0
returns the most negative repre-
sentable integer value. The ini-
tial value is (0, 0, 0, 0). See
glClearColor.

GL_COLOR_LOGIC_OP params returns a single boolean
value indicating whether a frag-
ment’s RGBA color values are
merged into the framebuffer using
a logical operation. The initial
value is GL_FALSE. See glLogi-
cOp.

GL_COLOR_MATERIAL params returns a single boolean
value indicating whether one or
more material parameters are
tracking the current color. The
initial value is GL_FALSE. See
glColorMaterial.

GL_COLOR_MATERIAL_FACE params returns one value, a sym-
bolic constant indicating which
materials have a parameter that
is tracking the current color.
The initial value is
GL_FRONT_AND_BACK. See glColor-
Material.

GL_COLOR_MATERIAL_PARAMETER
params returns one value, a
symbolic constant indicating
which material parameters are
tracking the current color. The
initial value is
GL_AMBIENT_AND_DIFFUSE. See
glColorMaterial.

GL_COLOR_WRITEMASK params returns four boolean val-
ues: the red, green, blue, and
alpha write enables for the color
buffers. The initial value is
(GL_TRUE, GL_TRUE, GL_TRUE,
GL_TRUE). See glColorMask.

GL_CULL_FACE params returns a single boolean
value indicating whether polygon
culling is enabled. The initial
value is GL_FALSE. See glCull-
Face.

GL_CULL_FACE_MODE params returns one value, a sym-
bolic constant indicating which
polygon faces are to be culled.
The initial value is GL_BACK.
See glCullFace.

GL_CURRENT_COLOR params returns four values: the
red, green, blue, and alpha val-
ues of the current color. Inte-
ger 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. The initial
value is (1, 1, 1, 1).

GL_CURRENT_INDEX params returns one value, the
current color index. The initial
value is 1. 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 repre-
sentable integer value, and -1.0
returns the most negative repre-
sentable integer value. The ini-
tial value is (0, 0, 1). See
glNormal.

GL_CURRENT_RASTER_COLOR params returns four values: the
red, green, blue, and alpha val-
ues of the current raster posi-
tion. Integer values, if
requested, are linearly mapped
from the internal floating-point
representation such that 1.0
returns the most positive repre-
sentable integer value, and -1.0
returns the most negative
representable integer value. The
initial value is (1, 1, 1, 1).
See glRasterPos.

GL_CURRENT_RASTER_DISTANCE
params returns one value, the
distance from the eye to the cur-
rent raster position. The initial
value is 0. See glRasterPos.

GL_CURRENT_RASTER_INDEX params returns one value, the
color index of the current raster
position. The initial value is 1.
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. The
initial value is (0, 0, 0, 1).
See glRasterPos.

GL_CURRENT_RASTER_POSITION_VALID
params returns a single boolean
value indicating whether the cur-
rent raster position is valid.
The initial value is GL_TRUE.
See glRasterPos.

GL_CURRENT_RASTER_TEXTURE_COORDS
params returns four values: the
s, t, r, and q current raster
texture coordinates. The initial
value is (0, 0, 0, 1). See
glRasterPos and glTexCoord.

GL_CURRENT_TEXTURE_COORDS
params returns four values: the
s, t, r, and q current texture
coordinates. The initial value is
(0, 0, 0, 1). See glTexCoord.

GL_DEPTH_BIAS params returns one value, the
depth bias factor used during
pixel transfers. The initial
value is 0. 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 repre-
sentable integer value, and -1.0
returns the most negative repre-
sentable integer value. The ini-
tial value is 1. See
glClearDepth.

GL_DEPTH_FUNC params returns one value, the
symbolic constant that indicates
the depth comparison function.
The initial value is GL_LESS.
See glDepthFunc.

GL_DEPTH_RANGE params returns two values: the
near and far mapping limits for
the depth buffer. Integer val-
ues, if requested, are linearly
mapped from the internal float-
ing-point representation such
that 1.0 returns the most posi-
tive representable integer value,
and -1.0 returns the most nega-
tive representable integer value.
The initial value is (0, 1). See
glDepthRange.

GL_DEPTH_SCALE params returns one value, the
depth scale factor used during
pixel transfers. The initial
value is 1. See glPixelTransfer.

GL_DEPTH_TEST params returns a single boolean
value indicating whether depth
testing of fragments is enabled.
The initial value is GL_FALSE.
See glDepthFunc and glDepthRange.

GL_DEPTH_WRITEMASK params returns a single boolean
value indicating if the depth
buffer is enabled for writing.
The initial value is GL_TRUE.
See glDepthMask.

GL_DITHER params returns a single boolean
value indicating whether dither-
ing of fragment colors and
indices is enabled. The initial
value is GL_TRUE.

GL_DOUBLEBUFFER params returns a single boolean
value indicating whether double
buffering is supported.

GL_DRAW_BUFFER params returns one value, a sym-
bolic constant indicating which
buffers are being drawn to. See
glDrawBuffer. The initial value
is GL_BACK if there are back
buffers, otherwise it is
GL_FRONT.

GL_EDGE_FLAG params returns a single boolean
value indicating whether the cur-
rent edge flag is GL_TRUE or
GL_FALSE. The initial value is
GL_TRUE. See glEdgeFlag.

GL_EDGE_FLAG_ARRAY params returns a single boolean
value indicating whether the edge
flag array is enabled. The ini-
tial value is GL_FALSE. See
glEdgeFlagPointer.

GL_EDGE_FLAG_ARRAY_STRIDE
params returns one value, the
byte offset between consecutive
edge flags in the edge flag
array. The initial value is 0.
See glEdgeFlagPointer.

GL_FOG params returns a single boolean
value indicating whether fogging
is enabled. The initial value is
GL_FALSE. See glFog.

GL_FOG_COLOR params returns four values: the
red, green, blue, and alpha com-
ponents of the fog color. Inte-
ger 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. The initial value is (0,
0, 0, 0). See glFog.

GL_FOG_DENSITY params returns one value, the fog
density parameter. The initial
value is 1. See glFog.

GL_FOG_END params returns one value, the end
factor for the linear fog equa-
tion. The initial value is 1.
See glFog.

GL_FOG_HINT params returns one value, a sym-
bolic constant indicating the
mode of the fog hint. The initial
value is GL_DONT_CARE. See
glHint.

GL_FOG_INDEX params returns one value, the fog
color index. The initial value is
0. See glFog.

GL_FOG_MODE params returns one value, a sym-
bolic constant indicating which
fog equation is selected. The
initial value is GL_EXP. See
glFog.

GL_FOG_START params returns one value, the
start factor for the linear fog
equation. The initial value is 0.
See glFog.

GL_FRONT_FACE params returns one value, a sym-
bolic constant indicating whether
clockwise or counterclockwise
polygon winding is treated as
front-facing. The initial value
is GL_CCW. See glFrontFace.

GL_GREEN_BIAS params returns one value, the
green bias factor used during
pixel transfers. The initial
value is 0.

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. The initial
value is 1. See glPixelTransfer.

GL_INDEX_ARRAY params returns a single boolean
value indicating whether the
color index array is enabled. The
initial value is GL_FALSE. See
glIndexPointer.

GL_INDEX_ARRAY_STRIDE params returns one value, the
byte offset between consecutive
color indexes in the color index
array. The initial value is 0.
See glIndexPointer.

GL_INDEX_ARRAY_TYPE params returns one value, the
data type of indexes in the color
index array. The initial value is
GL_FLOAT. See glIndexPointer.

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. The initial
value is 0. See glClearIndex.

GL_INDEX_LOGIC_OP params returns a single boolean
value indicating whether a frag-
ment’s index values are merged
into the framebuffer using a log-
ical operation. The initial value
is GL_FALSE. See glLogicOp.

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.
The initial value is 0. See
glPixelTransfer.

GL_INDEX_SHIFT params returns one value, the
amount that color and stencil
indices are shifted during pixel
transfers. The initial value is
0. See glPixelTransfer.

GL_INDEX_WRITEMASK params returns one value, a mask
indicating which bitplanes of
each color index buffer can be
written. The initial value is all
1’s. See glIndexMask.

GL_LIGHTi params returns a single boolean
value indicating whether the
specified light is enabled. The
initial value is GL_FALSE. See
glLight and glLightModel.

GL_LIGHTING params returns a single boolean
value indicating whether lighting
is enabled. The initial value is
GL_FALSE. See glLightModel.

GL_LIGHT_MODEL_AMBIENT params returns four values: the
red, green, blue, and alpha com-
ponents of the ambient intensity
of the entire scene. Integer
values, if requested, are lin-
early 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. The initial value is (0.2,
0.2, 0.2, 1.0). See glLight-
Model.

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. The initial value is
GL_FALSE. 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. The initial
value is GL_FALSE. See glLight-
Model.

GL_LINE_SMOOTH params returns a single boolean
value indicating whether
antialiasing of lines is enabled.
The initial value is GL_FALSE.
See glLineWidth.

GL_LINE_SMOOTH_HINT params returns one value, a sym-
bolic constant indicating the
mode of the line antialiasing
hint. The initial value is
GL_DONT_CARE. See glHint.

GL_LINE_STIPPLE params returns a single boolean
value indicating whether stip-
pling of lines is enabled. The
initial value is GL_FALSE. See
glLineStipple.

GL_LINE_STIPPLE_PATTERN params returns one value, the
16-bit line stipple pattern. The
initial value is all 1’s. See
glLineStipple.

GL_LINE_STIPPLE_REPEAT params returns one value, the
line stipple repeat factor. The
initial value is 1. See
glLineStipple.

GL_LINE_WIDTH params returns one value, the
line width as specified with
glLineWidth. The initial value is
1.

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.
The initial value is 0. See
glListBase.

GL_LIST_INDEX params returns one value, the
name of the display list cur-
rently under construction. 0 is
returned if no display list is
currently under construction. The
initial value is 0. See
glNewList.

GL_LIST_MODE params returns one value, a sym-
bolic constant indicating the
construction mode of the display
list currently under construc-
tion. The initial value is 0.
See glNewList.

GL_LOGIC_OP_MODE params returns one value, a sym-
bolic constant indicating the
selected logic operation mode.
The initial value is GL_COPY.
See glLogicOp.

GL_MAP1_COLOR_4 params returns a single boolean
value indicating whether 1D eval-
uation generates colors. The ini-
tial value is GL_FALSE. See
glMap1.

GL_MAP1_GRID_DOMAIN params returns two values: the
endpoints of the 1D map’s grid
domain. The initial value is (0,
1). See glMapGrid.

GL_MAP1_GRID_SEGMENTS params returns one value, the
number of partitions in the 1D
map’s grid domain. The initial
value is 1. See glMapGrid.

GL_MAP1_INDEX params returns a single boolean
value indicating whether 1D eval-
uation generates color indices.
The initial value is GL_FALSE.
See glMap1.

GL_MAP1_NORMAL params returns a single boolean
value indicating whether 1D eval-
uation generates normals. The
initial value is GL_FALSE. See
glMap1.

GL_MAP1_TEXTURE_COORD_1 params returns a single boolean
value indicating whether 1D eval-
uation generates 1D texture coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP1_TEXTURE_COORD_2 params returns a single boolean
value indicating whether 1D eval-
uation generates 2D texture coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP1_TEXTURE_COORD_3 params returns a single boolean
value indicating whether 1D eval-
uation generates 3D texture coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP1_TEXTURE_COORD_4 params returns a single boolean
value indicating whether 1D eval-
uation generates 4D texture coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP1_VERTEX_3 params returns a single boolean
value indicating whether 1D eval-
uation generates 3D vertex coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP1_VERTEX_4 params returns a single boolean
value indicating whether 1D eval-
uation generates 4D vertex coor-
dinates. The initial value is
GL_FALSE. See glMap1.

GL_MAP2_COLOR_4 params returns a single boolean
value indicating whether 2D eval-
uation generates colors. The ini-
tial value is GL_FALSE. See
glMap2.

GL_MAP2_GRID_DOMAIN params returns four values: the
endpoints of the 2D map’s $i$ and
$j$ grid domains. The initial
value is (0,1; 0,1). See glMap-
Grid.

GL_MAP2_GRID_SEGMENTS params returns two values: the
number of partitions in the 2D
map’s $i$ and $j$ grid domains.
The initial value is (1,1). See
glMapGrid.

GL_MAP2_INDEX params returns a single boolean
value indicating whether 2D eval-
uation generates color indices.
The initial value is GL_FALSE.
See glMap2.

GL_MAP2_NORMAL params returns a single boolean
value indicating whether 2D eval-
uation generates normals. The
initial value is GL_FALSE. See
glMap2.

GL_MAP2_TEXTURE_COORD_1 params returns a single boolean
value indicating whether 2D eval-
uation generates 1D texture coor-
dinates. The initial value is
GL_FALSE. See glMap2.

GL_MAP2_TEXTURE_COORD_2 params returns a single boolean
value indicating whether 2D eval-
uation generates 2D texture coor-
dinates. The initial value is
GL_FALSE. See glMap2.

GL_MAP2_TEXTURE_COORD_3 params returns a single boolean
value indicating whether 2D eval-
uation generates 3D texture coor-
dinates. The initial value is
GL_FALSE. See glMap2.

GL_MAP2_TEXTURE_COORD_4 params returns a single boolean
value indicating whether 2D eval-
uation generates 4D texture coor-
dinates. The initial value is
GL_FALSE. See glMap2.

GL_MAP2_VERTEX_3 params returns a single boolean
value indicating whether 2D eval-
uation generates 3D vertex coor-
dinates. The initial value is
GL_FALSE. See glMap2.

GL_MAP2_VERTEX_4 params returns a single boolean
value indicating whether 2D eval-
uation generates 4D vertex coor-
dinates. The initial value is
GL_FALSE. 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. The initial value is
GL_FALSE. See glPixelTransfer.

GL_MAP_STENCIL params returns a single boolean
value indicating if stencil
indices are to be replaced by
table lookup during pixel trans-
fers. The initial value is
GL_FALSE. See glPixelTransfer.

GL_MATRIX_MODE params returns one value, a sym-
bolic constant indicating which
matrix stack is currently the
target of all matrix operations.
The initial value is
GL_MODELVIEW. See glMatrixMode.

GL_MAX_CLIENT_ATTRIB_STACK_DEPTH
params returns one value indicat-
ing the maximum supported depth
of the client attribute stack.
See glPushClientAttrib.

GL_MAX_ATTRIB_STACK_DEPTH
params returns one value, the
maximum supported depth of the
attribute stack. The value must
be at least 16. See glPushAt-
trib.

GL_MAX_CLIP_PLANES params returns one value, the
maximum number of application-
defined clipping planes. The
value must be at least 6. See
glClipPlane.

GL_MAX_EVAL_ORDER params returns one value, the
maximum equation order supported
by 1D and 2D evaluators. The
value must be at least 8. See
glMap1 and glMap2.

GL_MAX_LIGHTS params returns one value, the
maximum number of lights. The
value must be at least 8. See
glLight.

GL_MAX_LIST_NESTING params returns one value, the
maximum recursion depth allowed
during display-list traversal.
The value must be at least 64.
See glCallList.

GL_MAX_MODELVIEW_STACK_DEPTH
params returns one value, the
maximum supported depth of the
modelview matrix stack. The value
must be at least 32. See glPush-
Matrix.

GL_MAX_NAME_STACK_DEPTH params returns one value, the
maximum supported depth of the
selection name stack. The value
must be at least 64. See glPush-
Name.

GL_MAX_PIXEL_MAP_TABLE params returns one value, the
maximum supported size of a
glPixelMap lookup table. The
value must be at least 32. See
glPixelMap.

GL_MAX_PROJECTION_STACK_DEPTH
params returns one value, the
maximum supported depth of the
projection matrix stack. The
value must be at least 2. See
glPushMatrix.

GL_MAX_TEXTURE_SIZE params returns one value. The
value gives a rough estimate of
the largest texture that the GL
can handle. If the GL version is
1.1 or greater, use
GL_PROXY_TEXTURE_1D or
GL_PROXY_TEXTURE_2D to determine
if a texture is too large. See
glTexImage1D and glTexImage2D.

GL_MAX_TEXTURE_STACK_DEPTH
params returns one value, the
maximum supported depth of the
texture matrix stack. The value
must be at least 2. See glPush-
Matrix.

GL_MAX_VIEWPORT_DIMS params returns two values: the
maximum supported width and
height of the viewport. These
must be at least as large as the
visible dimensions of the display
being rendered to. See glView-
port.

GL_MODELVIEW_MATRIX params returns sixteen values:
the modelview matrix on the top
of the modelview matrix stack.
Initially this matrix is the
identity matrix. See glPushMa-
trix.

GL_MODELVIEW_STACK_DEPTH params returns one value, the
number of matrices on the mod-
elview matrix stack. The initial
value is 1. See glPushMatrix.

GL_NAME_STACK_DEPTH params returns one value, the
number of names on the selection
name stack. The initial value is
0. See glPushName.

GL_NORMAL_ARRAY params returns a single boolean
value, indicating whether the
normal array is enabled. The ini-
tial value is GL_FALSE. See
glNormalPointer.

GL_NORMAL_ARRAY_STRIDE params returns one value, the
byte offset between consecutive
normals in the normal array. The
initial value is 0. See glNor-
malPointer.

GL_NORMAL_ARRAY_TYPE params returns one value, the
data type of each coordinate in
the normal array. The initial
value is GL_FLOAT. See glNormal-
Pointer.

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.
The initial value is GL_FALSE.
See glNormal.

GL_PACK_ALIGNMENT params returns one value, the
byte alignment used for writing
pixel data to memory. The initial
value is 4. See glPixelStore.

GL_PACK_LSB_FIRST params returns a single boolean
value indicating whether single-
bit pixels being written to mem-
ory are written first to the
least significant bit of each
unsigned byte. The initial value
is GL_FALSE. See glPixelStore.

GL_PACK_ROW_LENGTH params returns one value, the row
length used for writing pixel
data to memory. The initial value
is 0. See glPixelStore.

GL_PACK_SKIP_PIXELS params returns one value, the
number of pixel locations skipped
before the first pixel is written
into memory. The initial value is
0. 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. The initial
value is 0. 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. The initial value is
GL_FALSE. See glPixelStore.

GL_PERSPECTIVE_CORRECTION_HINT
params returns one value, a sym-
bolic constant indicating the
mode of the perspective correc-
tion hint. The initial value is
GL_DONT_CARE. See glHint.

GL_PIXEL_MAP_A_TO_A_SIZE params returns one value, the
size of the alpha-to-alpha pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_B_TO_B_SIZE params returns one value, the
size of the blue-to-blue pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_G_TO_G_SIZE params returns one value, the
size of the green-to-green pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_I_TO_A_SIZE params returns one value, the
size of the index-to-alpha pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_I_TO_B_SIZE params returns one value, the
size of the index-to-blue pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_I_TO_G_SIZE params returns one value, the
size of the index-to-green pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_I_TO_I_SIZE params returns one value, the
size of the index-to-index pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_I_TO_R_SIZE params returns one value, the
size of the index-to-red pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_R_TO_R_SIZE params returns one value, the
size of the red-to-red pixel
translation table. The initial
value is 1. See glPixelMap.

GL_PIXEL_MAP_S_TO_S_SIZE params returns one value, the
size of the stencil-to-stencil
pixel translation table. The
initial value is 1. See glPix-
elMap.

GL_POINT_SIZE params returns one value, the
point size as specified by
glPointSize. The initial value is
1.

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. The
smallest size must be at most 1,
and the largest size must be at
least 1. See glPointSize.

GL_POINT_SMOOTH params returns a single boolean
value indicating whether
antialiasing of points is
enabled. The initial value is
GL_FALSE. See glPointSize.

GL_POINT_SMOOTH_HINT params returns one value, a sym-
bolic constant indicating the
mode of the point antialiasing
hint. The initial value is
GL_DONT_CARE. See glHint.

GL_POLYGON_MODE params returns two values: sym-
bolic constants indicating
whether front-facing and back-
facing polygons are rasterized as
points, lines, or filled poly-
gons. The initial value is
GL_FILL. See glPolygonMode.

GL_POLYGON_OFFSET_FACTOR params returns one value, the
scaling factor used to determine
the variable offset that is added
to the depth value of each frag-
ment generated when a polygon is
rasterized. The initial value is
0. See glPolygonOffset.

GL_POLYGON_OFFSET_UNITS params returns one value. This
value is multiplied by an imple-
mentation-specific value and then
added to the depth value of each
fragment generated when a polygon
is rasterized. The initial value
is 0. See glPolygonOffset.

GL_POLYGON_OFFSET_FILL params returns a single boolean
value indicating whether polygon
offset is enabled for polygons in
fill mode. The initial value is
GL_FALSE. See glPolygonOffset.

GL_POLYGON_OFFSET_LINE params returns a single boolean
value indicating whether polygon
offset is enabled for polygons in
line mode. The initial value is
GL_FALSE. See glPolygonOffset.

GL_POLYGON_OFFSET_POINT params returns a single boolean
value indicating whether polygon
offset is enabled for polygons in
point mode. The initial value is
GL_FALSE. See glPolygonOffset.

GL_POLYGON_SMOOTH params returns a single boolean
value indicating whether
antialiasing of polygons is
enabled. The initial value is
GL_FALSE. See glPolygonMode.

GL_POLYGON_SMOOTH_HINT params returns one value, a sym-
bolic constant indicating the
mode of the polygon antialiasing
hint. The initial value is
GL_DONT_CARE. See glHint.

GL_POLYGON_STIPPLE params returns a single boolean
value indicating whether polygon
stippling is enabled. The initial
value is GL_FALSE. See glPoly-
gonStipple.

GL_PROJECTION_MATRIX params returns sixteen values:
the projection matrix on the top
of the projection matrix stack.
Initially this matrix is the
identity matrix. See glPushMa-
trix.

GL_PROJECTION_STACK_DEPTH
params returns one value, the
number of matrices on the projec-
tion matrix stack. The initial
value is 1. See glPushMatrix.

GL_READ_BUFFER params returns one value, a
symbolic constant indicating
which color buffer is selected
for reading. The initial value is
GL_BACK if there is a back
buffer, otherwise it is GL_FRONT.
See glReadPixels and glAccum.

GL_RED_BIAS params returns one value, the red
bias factor used during pixel
transfers. The initial value is
0.

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. The initial value is
1. See glPixelTransfer.

GL_RENDER_MODE params returns one value, a sym-
bolic constant indicating whether
the GL is in render, select, or
feedback mode. The initial value
is GL_RENDER. 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, followed by its
width and height. Initially the
$x$ and $y$ window coordinates
are both 0 and the width and
height are set to the size of the
window. See glScissor.

GL_SCISSOR_TEST params returns a single boolean
value indicating whether scissor-
ing is enabled. The initial value
is GL_FALSE. See glScissor.

GL_SHADE_MODEL params returns one value, a sym-
bolic constant indicating whether
the shading mode is flat or
smooth. The initial value is
GL_SMOOTH. See glShadeModel.

GL_STENCIL_BITS params returns one value, the
number of bitplanes in the sten-
cil buffer.

GL_STENCIL_CLEAR_VALUE params returns one value, the
index to which the stencil bit-
planes are cleared. The initial
value is 0. See glClearStencil.

GL_STENCIL_FAIL params returns one value, a sym-
bolic constant indicating what
action is taken when the stencil
test fails. The initial value is
GL_KEEP. See glStencilOp.

GL_STENCIL_FUNC params returns one value, a sym-
bolic constant indicating what
function is used to compare the
stencil reference value with the
stencil buffer value. The initial
value is GL_ALWAYS. See glSten-
cilFunc.

GL_STENCIL_PASS_DEPTH_FAIL
params returns one value, a sym-
bolic constant indicating what
action is taken when the stencil
test passes, but the depth test
fails. The initial value is
GL_KEEP. See glStencilOp.

GL_STENCIL_PASS_DEPTH_PASS
params returns one value, a sym-
bolic constant indicating what
action is taken when the stencil
test passes and the depth test
passes. The initial value is
GL_KEEP. See glStencilOp.

GL_STENCIL_REF params returns one value, the
reference value that is compared
with the contents of the stencil
buffer. The initial value is 0.
See glStencilFunc.

GL_STENCIL_TEST params returns a single boolean
value indicating whether stencil
testing of fragments is enabled.
The initial value is GL_FALSE.
See glStencilFunc and glSten-
cilOp.

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. The initial
value is all 1’s. See glStencil-
Func.

GL_STENCIL_WRITEMASK params returns one value, the
mask that controls writing of the
stencil bitplanes. The initial
value is all 1’s. See glStencil-
Mask.

GL_STEREO params returns a single boolean
value indicating whether stereo
buffers (left and right) are sup-
ported.

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. The ini-
tial value is 4.

GL_TEXTURE_1D params returns a single boolean
value indicating whether 1D
texture mapping is enabled. The
initial value is GL_FALSE. See
glTexImage1D.

GL_TEXTURE_1D_BINDING params returns a single value,
the name of the texture currently
bound to the target
GL_TEXTURE_1D. The initial value
is 0. See glBindTexture.

GL_TEXTURE_2D params returns a single boolean
value indicating whether 2D tex-
ture mapping is enabled. The ini-
tial value is GL_FALSE. See
glTexImage2D.

GL_TEXTURE_2D_BINDING params returns a single value,
the name of the texture currently
bound to the target
GL_TEXTURE_2D. The initial value
is 0. See glBindTexture.

GL_TEXTURE_COORD_ARRAY params returns a single boolean
value indicating whether the tex-
ture coordinate array is enabled.
The initial value is GL_FALSE.
See glTexCoordPointer.

GL_TEXTURE_COORD_ARRAY_SIZE
params returns one value, the
number of coordinates per element
in the texture coordinate array.
The initial value is 4. See
glTexCoordPointer.

GL_TEXTURE_COORD_ARRAY_STRIDE
params returns one value, the
byte offset between consecutive
elements in the texture coordi-
nate array. The initial value is
0. See glTexCoordPointer.

GL_TEXTURE_COORD_ARRAY_TYPE
params returns one value, the
data type of the coordinates in
the texture coordinate array. The
initial value is GL_FLOAT. See
glTexCoordPointer.

GL_TEXTURE_GEN_Q params returns a single boolean
value indicating whether auto-
matic generation of the q texture
coordinate is enabled. The ini-
tial value is GL_FALSE. See
glTexGen.

GL_TEXTURE_GEN_R params returns a single boolean
value indicating whether auto-
matic generation of the r texture
coordinate is enabled. The ini-
tial value is GL_FALSE. See
glTexGen.

GL_TEXTURE_GEN_S params returns a single boolean
value indicating whether auto-
matic generation of the S texture
coordinate is enabled. The ini-
tial value is GL_FALSE. See
glTexGen.

GL_TEXTURE_GEN_T params returns a single boolean
value indicating whether auto-
matic generation of the T texture
coordinate is enabled. The ini-
tial value is GL_FALSE. See
glTexGen.

GL_TEXTURE_MATRIX params returns sixteen values:
the texture matrix on the top of
the texture matrix stack. Ini-
tially this matrix is the iden-
tity matrix. See glPushMatrix.

GL_TEXTURE_STACK_DEPTH params returns one value, the
number of matrices on the texture
matrix stack. The initial value
is 1. See glPushMatrix.

GL_UNPACK_ALIGNMENT params returns one value, the
byte alignment used for reading
pixel data from memory. The ini-
tial value is 4. See glPixel-
Store.

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. The initial value is
GL_FALSE. See glPixelStore.

GL_UNPACK_ROW_LENGTH params returns one value, the row
length used for reading pixel
data from memory. The initial
value is 0. See glPixelStore.

GL_UNPACK_SKIP_PIXELS params returns one value, the
number of pixel locations skipped
before the first pixel is read
from memory. The initial value is
0. 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. The initial
value is 0. 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. The initial value is
GL_FALSE. See glPixelStore.

GL_VERTEX_ARRAY params returns a single boolean
value indicating whether the ver-
tex array is enabled. The initial
value is GL_FALSE. See glVertex-
Pointer.

GL_VERTEX_ARRAY_SIZE params returns one value, the
number of coordinates per vertex
in the vertex array. The initial
value is 4. See glVertexPointer.

GL_VERTEX_ARRAY_STRIDE params returns one value, the
byte offset between consecutive
vertexes in the vertex array. The
initial value is 0. See glVert-
exPointer.

GL_VERTEX_ARRAY_TYPE params returns one value, the
data type of each coordinate in
the vertex array. The initial
value is GL_FLOAT. See glVertex-
Pointer.

GL_VIEWPORT params returns four values: the
$x$ and $y$ window coordinates of
the viewport, followed by its
width and height. Initially the
$x$ and $y$ window coordinates
are both set to 0, and the width
and height are set to the width
and height of the window into
which the GL will do its render-
ing. See glViewport.

GL_ZOOM_X params returns one value, the $x$
pixel zoom factor. The initial
value is 1. See glPixelZoom.

GL_ZOOM_Y params returns one value, the $y$
pixel zoom factor. The initial
value is 1. See glPixelZoom.

Many of the boolean parameters can also be queried more
easily using glIsEnabled.

NOTES
GL_COLOR_LOGIC_OP, GL_COLOR_ARRAY, GL_COLOR_ARRAY_SIZE,
GL_COLOR_ARRAY_STRIDE, GL_COLOR_ARRAY_TYPE,
GL_EDGE_FLAG_ARRAY, GL_EDGE_FLAG_ARRAY_STRIDE,
GL_INDEX_ARRAY, GL_INDEX_ARRAY_STRIDE,
GL_INDEX_ARRAY_TYPE, GL_INDEX_LOGIC_OP, GL_NORMAL_ARRAY,
GL_NORMAL_ARRAY_STRIDE, GL_NORMAL_ARRAY_TYPE,
GL_POLYGON_OFFSET_UNITS, GL_POLYGON_OFFSET_FACTOR,
GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE,
GL_POLYGON_OFFSET_POINT, GL_TEXTURE_COORD_ARRAY,
GL_TEXTURE_COORD_ARRAY_SIZE,
GL_TEXTURE_COORD_ARRAY_STRIDE,
GL_TEXTURE_COORD_ARRAY_TYPE, GL_VERTEX_ARRAY,
GL_VERTEX_ARRAY_SIZE, GL_VERTEX_ARRAY_STRIDE, and
GL_VERTEX_ARRAY_TYPE are available only if the GL version
is 1.1 or greater.

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
glGetClipPlane, glGetError, glGetLight, glGetMap, glGetMa-
terial, glGetPixelMap, glGetPointerv, glGetPolygonStipple,
glGetString, glGetTexEnv, glGetTexGen, glGetTexImage,
glGetTexLevelParameter, glGetTexParameter, glIsEnabled

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