[GRASS-dev] lib fn to convert int color number to RGB values?
glynn at gclements.plus.com
Fri Feb 1 07:09:26 EST 2008
Ivan Shmakov wrote:
> > RGBA_Color was recently added (as was RGB support for modules' CLI
> > options) so 1) it could be used to pass RGB arround without having to
> > call the display library and 2) we could handle a color value of
> > 'none' without needing to pass a separate variable or rely on the
> > palette index number set to -1. Currently the alpha channel is just
> > set to 0 or 255 for full-transparency ('none') or full-opacity.
> Could the attached (untested) patch be of any help?
First, you would need:
+typedef struct RGBA_Color
unsigned char r, g, b, a; /* red, green, blue, and alpha */
} RGBA_Color ;
Normally, we use structure tags rather than typedefs. The RGBA_Color
structure and the STD_OPT enum are the only exceptions I see in gis.h.
But, replacing color_rgb with RGBA_Color should be straightforward.
Glynn Clements <glynn at gclements.plus.com>
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