[Radiance-general] Re: Custom false color palette

[Greg Ward]

Hi Dave,

Your formula should be fine, you just need to remember there's no  
implied multiplication.  Instead of:

	if(v-5/7,1,if(v-4/7,7v-4,if(v-2/7,0,if(v-1/7,2-7v,7v))))

use:

	falsecolor -r "if(v-5/7,1,if(v-4/7,7*v-4,if(v-2/7,0,if(v-1/7,2-7*v, 
7*v))))" ...

Hope this helps.
-Greg

> From: "David Smith" <dbs176 at gmail.com>
> Date: September 17, 2008 3:10:32 PM PDT
>
> I'm trying to make a false color / pseudo color image that matches the
> color palette from a non-lighting program. It would work great with
> four nested IF statements, but falsecolor -r/g/b doesn't seem to want
> to take them. Has anybody come up with a workaround for this or am I
> better off editing the falsecolor script?
>
> Perhaps there is a way to use higher order functions?
>
> Here's an image of the scale and a close numerical pseudocolor
> traversal: http://tinyurl.com/4e2x7m
>
> This would be the if statement for the falsecolor -r argument:
> if(v-5/7,1,if(v-4/7,7v-4,if(v-2/7,0,if(v-1/7,2-7v,7v))))
>
> --Dave