Use Below Range Color option doesn't seem to respect "below"

See below image. I’m noticing in my datasets that when a value is 0.0, and I have a colorbar range set to [0.0, <value>] that the Use Below Range Color option is being used for values equal to or less than the minimum value, rather than simply less than.

A simple way to replicate is to create a Box source, add a Generate Surface Normals filter, and then specify to use the Above/Below range colors:

Notice how the maximum value (+1) is respected (surface is red, not yellow), but the minimum value (-1) isn’t (surface is green, not blue). Seems like even if the cause is some floating-point nonsense, rather than a <= instead of <, that it might make sense to do a tolerant comparison.

Colormaps should really support both open and closed interval endpoints. I agree this is a missing feature; it will take some shader code to correct it.

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