plscolbga: Set the background color by 8-bit RGB value and double alpha transparency value.

plscolbga (r,
 g,
 b,
 alpha);
 

Set the background color (color 0 in color map 0) by 8-bit RGB value (see the section called “Color Map0”) and double alpha transparency value.

r (PLINT, input)

Unsigned 8-bit integer (0-255) representing the degree of red in the color.

g (PLINT, input)

Unsigned 8-bit integer (0-255) representing the degree of green in the color.

b (PLINT, input)

Unsigned 8-bit integer (0-255) representing the degree of blue in the color.

alpha (PLFLT, input)

double value (0.0-1.0) representing the alpha transparency value of the color.

This function is used in example 31.