Here is a change set with a new BitBlt rule called hsv:with:
It a rough version of a hue, saturation and brightness 
rule, with the hue, saturation and brightness passed in
a halftone form. A class called HSVConverter helps create a 
integer with the values:
HSVConverter hue: (0-360) saturation: (0.0-1.0)  brightness:(0.0-1.0)
Here is a short doIt to get you start testing:

bits _ HSVConverter hue: 60 saturation:0.0 brightness:0.4.
source _ Form fromFileNamed:'path/to/form'."32 bit depth !"
hf _ Form extent:1 at 1 depth:32 bits: bits.
dest _ Form extent:source extent depth:32.
(BitBlt
		destForm: dest
		sourceForm: source
		halftoneForm:hf
		combinationRule:39
		destOrigin:0 @ 0
		sourceOrigin:0 @ 0
		extent:source extent
		clipRect: source computeBoundingBox)copyBits."without the compiled
Plugin use copyBitsSimulated"
(SketchMorph withForm: dest) openInWorld


A BitBltPlugin compiled for MacOS 7 to 9 PPC is included.

ToDo: Pass negative values so hue, saturation and brightness can be 
reduced!

Karl
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