I have several solid/filled colored objects drawn and when they overlap I would like there colors to blend.
Basically I have things that represent stuff like a warning = yellow, error = red, safe = green, etc...
When these objects overlap I want there colors to represent the combined effect. When we have a warning with safe we have overlap of a yellow object with a green which will give a yellow-green color. If we have an error with safe we have a red-green color for the overlap. If we have a warning-error-safe overlap then we have a yellow-red-green color all in equal proportions.
Any idea how to do this in tikz or anything else in tex?