I am no longer able to reproduce one of my scenes due to the change in 
exponentiation in 3.5, now in the form of pow(a,b) - formerly a^b.

The scene uses a particularly pathological function for an isosurface, in which 
negative floating point values are raised to floating point powers - a situation 
where the results are normally undefined.

When I was able to generate my scene using the form a^b, "legal" values were 
generated and pixels were rendered for negative floating point 'a' and floating 
point 'b'.

In 3.5, using pow(a,b) I just get black.

Is there some way of emulating the old a^b in order to render my scene?

Yes, I could go back to 3.1 but I am hoping the faster render speed of 3.5 would 
avoid my ordeal in 3.1 - I had to wait over 38 hours for a top quality 320 x 240!

What is the big difference in implementation of exponentiation in the new version, 
and why was it altered?

Many thanks for any help,


Bob Douglas

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