plgcol0a: Returns 8-bit RGB values and double alpha value for given color from color map0.

Returns 8-bit RGB values (0-255) and double alpha value (0.0 - 1.0) for given color from color map0 (see the Section called Color Map0 in Chapter 3). Values are negative if an invalid color id is given.

icol0 (PLINT, input) Index of desired cmap0 color. r (PLINT *, output) Pointer to 8-bit red value. g (PLINT *, output) Pointer to 8-bit green value. b (PLINT *, output) Pointer to 8-bit blue value. a (PLFLT *, output) Pointer to PLFLT alpha value.

This function is used in example 30.