plgcolbga: Returns the background color (cmap0[0]) by 8-bit RGB value and double alpha transparency value

plgcolbga (r,
 g,
 b,
 alpha);
 

Returns the background color (cmap0[0]) by 8-bit RGB value and double alpha transparency value.

r (PLINT *, output)

Pointer to an unsigned 8-bit integer (0-255) representing the degree of red in the color.

g (PLINT *, output)

Pointer to an unsigned 8-bit integer (0-255) representing the degree of green in the color.

b (PLINT *, output)

Pointer to an unsigned 8-bit integer (0-255) representing the degree of blue in the color.

alpha (PLFLT *, output)

Pointer to PLFLT alpha transparency value.

This function is used in example 31.