Quote - So we have to approach the question by testing assumptions.

The most important assumption is this - does SM keep hypocolors (less than 0) or does it clamp them at 0?

This is a fundamental thing I talked about early on in this thread - that Poser allows us to manipulate colors as arbitrary numbers, even if the intermediate results cannot be "looked at" on a computer monitor.

This is easy to test.

Start with the original texture. Use a brick to subtract white. Then use another brick to add white.

This is (x - k) in the first brick.

Then (x - k) + k in the second brick.

If you do not see x, the original image, then something non-linear happened in the middle. If it is completely white, the intermediate value was clamped.

If SM clamps intermediate results (no less than 0, no more than 1) then you are screwed and cannot make the same things as we can in Poser.

(NOTE: Had to edit - earlier I sad completely black. I meant white.)

Precisely what I was thinking...

And I apologise for not being clearer in what I was trying to say.

What I'm trying to establish is where SM bricks differ from Poser node in behaviour... what they do beneath the surface. There's no Bagginsbill for Brick behaviour... well, perhaps the developers themselves, but they ain't talking.

So, I'm using your testing methods to make sure what I think I see is actually what is happening. The Microscope/magnifying glass approach. So, I'm re-doing all the exercises we did in this thread both in Poser, and then setting them up in SM.

Sorry for wasting your time, Bill, because I was unclear... and thank you again for all the help you have given over the past years! Your patience and tolerance does you credit! Not to mention your generosity with your time!

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

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