glGetColorTableParameter(3G) OpenGL Reference glGetColorTableParameter(3G)NAME
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 )
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 format 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 format and size
parameters are set by glColorTable.
The following table lists the format 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.
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glGetColorTableParameter(3G) OpenGL Reference glGetColorTableParameter(3G)
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Parameter N Meaning
__________________________________________________________________
GL_COLOR_TABLE_FORMAT 1 Internal format (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
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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.
MACHINE DEPENDENCIES
The SGI_color_table extension is not supported on RealityEngine,
RealityEngine2, and VTX systems.
SEE ALSO
glColorTable, glTexParameter, glColorTableParameter
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