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<p>Hi people,</p>
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<p>I'm currently writing a patch to rework the state of blending operations inside of Blender. Right now the operations are defined in multiple places around the code base so I thought it could be good to ease out maintenance of that part of the code and to have them all defined in one place. So far, so good.</p>
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<p>By running some speed-tests, out of curiosity, I noticed that (at least in the compositor) the Hue, Saturation, Color and Value modes were the slowest. And that is apparently due to multiple RGB <-> HSV conversions. So I did some searches and found some interesting simple formulas which do not rely on those conversions.</p>
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<p>Now, these modes are a little faster (~10-12%), but they do look a little different than before, especially the Value blend mode(, and that is a little strange).</p>
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<p>So the question is: would the users (especially module members) agree on that change ?</p>
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<p>To have a look at the patch, or to test it, or just to see the difference between the before and after for those above mentioned operations, please head over to http://developer.blender.org/D539 . I have uploaded there a few images demonstrating the changes.</p>
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<div>Sincerely,</div>
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<div>Kévin Dietrich.</div>
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