HP b2600 Reference Manual page 335

Each index is shifted GL_INDEX_SHIFT bits just as a color index is, then added to
GL_INDEX_OFFSET. If GL_MAP_STENCIL is true, each index is masked by 2
where n is GL_PIXEL_MAP_S_TO_S_SIZE, then replaced by the contents of
GL_PIXEL_MAP_S_TO_S indexed by the masked value.
The following table gives the type, initial value, and range of valid values for each of the
pixel transfer parameters that are set with glPixelTransfer.
pname
GL_MAP_COLOR
GL_MAP_STENCIL
GL_INDEX_OFFSET
GL_BLUE_SCALE
GL_ALPHA_SCALE
GL_DEPTH_SCALE
GL_BLUE_BIAS
glPixelTransferf can be used to set any pixel transfer parameter. If the parameter type is
boolean, 0 implies false and any other value implies true. If pname is an integer
parameter, param is rounded to the nearest integer.
Likewise, glPixelTransferi can be used to set any of the pixel transfer parameters.
Boolean parameters are set to false if param is 0 and to true otherwise. param is
converted to floating point before being assigned to real-valued parameters.
Notes
If a glCopyPixels, glCopyTexImage1D,glCopyTexImage2D, glCopyTexSubImage1D,
glCopyTexSubImage2D, glDrawPixels, glReadPixels, glTexImage1D, glTexImage2D,
glTexSubImage1D, or glTexSubImage2D command is placed in a display list (see
glNewList and glCallList), the pixel transfer mode settings in effect when the display
list is executed are the ones that are used. They may be different from the settings when
the command was compiled into the display list.
Chapter 14
GL_INDEX_SHIFT
GL_RED_SCALE
GL_GREEN_SCALE
GL_RED_BIAS
GL_GREEN_BIAS
GL_ALPHA_BIAS
GL_DEPTH_BIAS
Initial
Type
Value
boolean false
boolean false
integer 0
integer 0
float 1
float 1
float 1
float 1
float 1
float 0
float 0
float 0
float 0
float 0
glPixelTransfer
n
- 1,
Valid
Range
true/false
true/false
( -
( -
( -
( -
( -
( -
( -
( -
( -
( -
( -
( -
P
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