GLGETCOLORTABLEPARAMETERSGI(3gl)GLGETCOLORTABLEPARAMETERSGI(3gl)NAME
glGetColorTableParameterSGI - get color lookup table parameters
C SPECIFICATION
void glGetColorTableParameterivSGI( GLenum target,
GLenum pname
GLint* params)
void glGetColorTableParameterfvSGI( GLenum target,
GLenum pname,
GLfloat* params)
PARAMETERS
target The target color table. Must be GL_TEXTURE_COLOR_TABLE_SGI,
GL_COLOR_TABLE_SGI, GL_PROXY_TEXTURE_COLOR_TABLE_SGI, or
GL_PROXY_COLOR_TABLE_SGI.
pname The symbolic name of a color lookup table parameter. Must be
one of GL_COLOR_TABLE_BIAS_SGI, GL_COLOR_TABLE_SCALE_SGI,
GL_COLOR_TABLE_FORMAT_SGI, GL_COLOR_TABLE_WIDTH_SGI,
GL_COLOR_TABLE_RED_SIZE_SGI, GL_COLOR_TABLE_GREEN_SIZE_SGI,
GL_COLOR_TABLE_BLUE_SIZE_SGI, GL_COLOR_TABLE_ALPHA_SIZE_SGI,
GL_COLOR_TABLE_LUMINANCE_SIZE_SGI, or GL_COLOR_TABLE_INTEN‐
SITY_SIZE_SGI.
params A pointer to an array where the values of the parameter will be
stored.
DESCRIPTION
glGetColorTableParameterSGI is part of the GL_SGI_color_table exten‐
sion, which adds several color lookup tables to the pixel transfer
path. It is also used by GL_SGI_texture_color_table, which adds a color
table lookup to the texturing process.
When pname is set to GL_COLOR_TABLE_SCALE_SGI or GL_COLOR_TA‐
BLE_BIAS_SGI, glGetColorTableParameterSGI returns the color table scale
or bias parameters for the table specified by target. For these
queries, target must be set to GL_TEXTURE_COLOR_TABLE_SGI or
GL_COLOR_TABLE_SGI,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.
glGetColorTableParameterSGI 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. (For
example, set target to either GL_TEXTURE_COLOR_TABLE_SGI or
GL_PROXY_TEXTURE_COLOR_TABLE_SGI.) The format and size parameters are
set by glColorTableSGI.
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.
┌───────────────────────────────────────────────────────────────────────┐
│ pname N Meaning │
│ │
├───────────────────────────────────────────────────────────────────────┤
│GL_COLOR_TABLE_FORMAT_SGI 1 Internal format (e.g. GL_RGBA) │
│GL_COLOR_TABLE_WIDTH_SGI 1 Number of elements in table │
│GL_COLOR_TABLE_RED_SIZE_SGI 1 Size of red component, in bits │
│GL_COLOR_TABLE_GREEN_SIZE_SGI 1 Size of green component │
│GL_COLOR_TABLE_BLUE_SIZE_SGI 1 Size of blue component │
│GL_COLOR_TABLE_ALPHA_SIZE_SGI 1 Size of alpha component │
│GL_COLOR_TABLE_LUMINANCE_SIZE_SGI 1 Size of luminance component │
│GL_COLOR_TABLE_INTENSITY_SIZE_SGI 1 Size of intensity component │
└───────────────────────────────────────────────────────────────────────┘
NOTES
If target is set to GL_TEXTURE_COLOR_TABLE_SGI and the GL_SGI_tex‐
ture_color_table extension is not supported then an GL_INVALID_ENUM
error is generated.
If target is set to GL_COLOR_TABLE_SGI, and the GL_SGI_color_table
extension is not supported, then an GL_INVALID_ENUM error is generated.
ERRORS
GL_INVALID_ENUM is generated if target or pname is not an acceptable
value.
GL_INVALID_OPERATION is generated if glGetColorTableParameterSGI is
executed between the execution of glBegin and the corresponding execu‐
tion of glEnd.
SEE ALSO
glColorTableSGI, glColorTableParameterSGI
15 Mar 97 GLGETCOLORTABLEPARAMETERSGI(3gl)