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Hi !
I am writing a 3D shader and I got this graph and I just can't figure out the function
The result value (given in greyscale values between 0=black and 1=white) depends on the two variables a and b.
It is for example,
0.5 when a=b
1 when a=1
0 when b=1
0.5+(a/2) when b=0
0.5+(b/2) when a=0
(is there a name for this kind of graph btw.?)
I think it must be a quite simple function.
Thanks in advanced for help
Ray
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Calculate the slope (or angle) from any point to (1,1) and base it on that.
Example: (0.2,0.2) ==> Slope = (1-0.2)/(1-0.2) = 1 = 45°
Example: (0.9,0.2) ==> Slope = (1-0.2)/(1-0.9) = 8 = 83°
So you could say the first point was 45°/90° = 0.5, and the second 83°/90° = 0.92
That should get you close.
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
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Thanks!
I have the solution now as:
if( (1-a) < (1-b) )
r = 1 - ( (1-a) / (1-b) ) / 2;
else
r = ( (1-b) / (1-a) ) / 2;
Ray
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