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Date: Mon, 9 Jul 2012 21:21:46 +0200 From: calculemus1988 gmail com To: gimp-developer-list gnome org Subject: [Gimp-developer] Multiply blend mode in GIMP I am reading this: docs.gimp.org/en/gimp-concepts-layer-modes.html and I wonder why is the formula for "Multiply", E = (M * I) / 255? Why divide with 255, that is the part that confuses me. Should it not be just M * I and then clamp the result in range 0 to 255? Thanks _______________________________________________ gimp-developer-list mailing list gimp-developer-list gnome org https://mail.gnome.org/mailman/listinfo/gimp-developer-list Other people have answered it already, but an alternate way of looking at the Multiply formula is: E = M * (I / 255) ...or... E = (M/255) * I Where M (the multiply layer) values are expressed in a 0...255 range, therefore, (M/255) yields a 0-1.0 percentage and that is exactly the behavior we need. The documentation could probably be phrased just a little better. -- Stratadrake strata_ranger hotmail com -------------------- Numbers may not lie, but neither do they tell the whole truth. |