On Wed, Jan 09, 2008 at 08:24:32AM +0100, Arjen Markus wrote: > > The 0.0-1.0 range is also used in Tk 8.5 with 0 completely transparant > and 1 completely opaque. So that supports your impression. > > The libgd convention seems rather arbitrary to me (127 as the maximum? > Why not 255, as with the RGB values?)
According to the comments in gd.h : gd 1.x used signed integers for colours, with negative numbers denoting special cases. For compatibility gd 2.x maintained this. With a 32-bit integer this only leaves 7 bits for the alpha values. Seems like a bit of a bodgy to me, but there we are... Andrew ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
