In the Houdini colorbar HDA under "color options", set the menus like this...


Details:

png file /svs/share/houdini/cbars/images/png/cool_warm_perceptual.png
tex file /svs/share/houdini/cbars/images/tex/cool_warm_perceptual.tex
definition /svs/share/houdini/cbars/definitions/svs/cool_warm_perceptual.csv
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