glGetColorTableParameterfv, glGetColorTableParameteriv
- get color lookup table parameters
C SPECIFICATION
void glGetColorTableParameterfv(
GLenum target,
GLenum pname,
GLfloat *params )
void glGetColorTableParameteriv(
GLenum target,
GLenum pname,
GLint *params )
delim $$
PARAMETERS
target
The target color table.
Must be
GL_COLOR_TABLE,
GL_POST_CONVOLUTION_COLOR_TABLE,
GL_POST_COLOR_MATRIX_COLOR_TABLE,
GL_PROXY_COLOR_TABLE,
GL_PROXY_POST_CONVOLUTION_COLOR_TABLE,
GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE.
pname
The symbolic name of a color lookup table parameter.
Must be one of
GL_COLOR_TABLE_BIAS,
GL_COLOR_TABLE_SCALE,
GL_COLOR_TABLE_FORMAT,
GL_COLOR_TABLE_WIDTH,
GL_COLOR_TABLE_RED_SIZE,
GL_COLOR_TABLE_GREEN_SIZE,
GL_COLOR_TABLE_BLUE_SIZE,
GL_COLOR_TABLE_ALPHA_SIZE,
GL_COLOR_TABLE_LUMINANCE_SIZE, or
GL_COLOR_TABLE_INTENSITY_SIZE.
params
A pointer to an array where the values of the parameter will be stored.
DESCRIPTION
Returns parameters specific to color table target.
When pname is set to GL_COLOR_TABLE_SCALE or
GL_COLOR_TABLE_BIAS, glGetColorTableParameter returns the color
table scale or bias parameters for the table specified by target.
For these queries, target must be set to
GL_COLOR_TABLE,
GL_POST_CONVOLUTION_COLOR_TABLE,
or GL_POST_COLOR_MATRIX_COLOR_TABLE and
params points to an array of four elements, which receive
the scale or bias factors for red, green, blue, and alpha, in that order.
glGetColorTableParameter can also be used to retrieve the and size parameters
for a color table. For these queries, set target to either the
color table target or the proxy color table target.
The and size parameters are set by glColorTable.
The following table lists the and size parameters that may
be queried.
For each symbolic constant listed below for pname,
params must point to an array of the
given length, and receive the values indicated.
Parameter
N
Meaning
GL_COLOR_TABLE_FORMAT
1
Internal (e.g. GL_RGBA)
GL_COLOR_TABLE_WIDTH
1
Number of elements in table
GL_COLOR_TABLE_RED_SIZE
1
Size of red component, in bits
GL_COLOR_TABLE_GREEN_SIZE
1
Size of green component
GL_COLOR_TABLE_BLUE_SIZE
1
Size of blue component
GL_COLOR_TABLE_ALPHA_SIZE
1
Size of alpha component
GL_COLOR_TABLE_LUMINANCE_SIZE
1
Size of luminance component
GL_COLOR_TABLE_INTENSITY_SIZE
1
Size of intensity component
NOTES
glGetColorTableParameter is present only if GL_ARB_imaging is returned when glGetString
is called with an argument of GL_EXTENSIONS.
ERRORS
GL_INVALID_ENUM is generated if target or pname is not
an acceptable value.
GL_INVALID_OPERATION is generated if glGetColorTableParameter is executed
between the execution of glBegin and the corresponding
execution of glEnd.