glGetColorTable
- retrieve contents of a color lookup table
C SPECIFICATION
void glGetColorTable(
GLenum target,
GLenum format,
GLenum type,
GLvoid *table )
PARAMETERS
target
Must be GL_COLOR_TABLE,
GL_POST_CONVOLUTION_COLOR_TABLE,
or
GL_POST_COLOR_MATRIX_COLOR_TABLE.
format
The of the pixel data in table.
The possible values are
GL_RED,
GL_GREEN,
GL_BLUE,
GL_ALPHA,
GL_LUMINANCE,
GL_LUMINANCE_ALPHA,
GL_RGB,
GL_BGR,
GL_RGBA, and
GL_BGRA.
type
The type of the pixel data in table.
Symbolic constants
GL_UNSIGNED_BYTE,
GL_BYTE,
GL_BITMAP,
GL_UNSIGNED_SHORT,
GL_SHORT,
GL_UNSIGNED_INT,
GL_INT,
GL_FLOAT,
GL_UNSIGNED_BYTE_3_3_2,
GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5,
GL_UNSIGNED_SHORT_5_6_5_REV,
GL_UNSIGNED_SHORT_4_4_4_4,
GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1,
GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8,
GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, and
GL_UNSIGNED_INT_2_10_10_10_REV
are accepted.
table
Pointer to a one-dimensional array of pixel data containing the contents
of the color table.
DESCRIPTION
glGetColorTable returns in table the contents of the color table specified
by target. No pixel transfer operations are performed, but pixel
storage modes that are applicable to
glReadPixels are performed.
Color components that are requested in
the specified format, but which are not included in the internal
of the color lookup table, are returned as zero. The
assignments of internal color components to the components
requested by format are
Internal Component
Resulting Component
red
red
green
green
blue
blue
alpha
alpha
luminance
red
intensity
red
NOTES
glGetColorTable 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 is not one of the allowable
values.
GL_INVALID_ENUM is generated if format is not one of the allowable
values.
GL_INVALID_ENUM is generated if type is not one of the allowable
values.
GL_INVALID_OPERATION is generated if type is one of
GL_UNSIGNED_BYTE_3_3_2,
GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, or
GL_UNSIGNED_SHORT_5_6_5_REV
and format is not GL_RGB.
GL_INVALID_OPERATION is generated if type is one of
GL_UNSIGNED_SHORT_4_4_4_4,
GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1,
GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8,
GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, or
GL_UNSIGNED_INT_2_10_10_10_REV
and format is neither GL_RGBA nor GL_BGRA.
GL_INVALID_OPERATION is generated if glGetColorTable is executed
between the execution of glBegin and the corresponding
execution of glEnd.
