plgcol0a: Returns 8-bit RGB values and PLFLT alpha transparency value for given color index from cmap0
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plgcol0a: Returns 8-bit RGB values and PLFLT alpha transparency value for given color index from cmap0

plgcol0a (icol0,
 r,
 g,
 b,
 alpha);
 

Returns 8-bit RGB values (0-255) and PLFLT alpha transparency value (0.0-1.0) for given color from cmap0 (see the section called “Color Map0”). Values are negative if an invalid color id is given.

icol0 (PLINT, input)

Index of desired cmap0 color.

r (PLINT_NC_SCALAR, output)

Returned value of the red intensity in the range from 0 to 255.

g (PLINT_NC_SCALAR, output)

Returned value of the green intensity in the range from 0 to 255.

b (PLINT_NC_SCALAR, output)

Returned value of the blue intensity in the range from 0 to 255.

alpha (PLFLT_NC_SCALAR, output)

Returned value of the alpha transparency in the range from (0.0-1.0).

Redacted form: plgcola(r, g, b)

This function is used in example 30.

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plgcol0: Returns 8-bit RGB values for given color index from cmap0  Home  plgcolbg: Returns the background color (cmap0[0]) by 8-bit RGB value