Transparency in plot and scale

I tend to use transparency (-t[n]) on layers with grids plotted with grdimage and a CPT.

When plotting the color scale with psscale, the colors are opaque, so they have a different look than what is present in the actual map. One solution is to use -t[n] in the psscale command, but this makes everything in that layer transparent - including text. Any way to make the colors in the scale have the same transparency as in the grdimage-layer without affecting the text?

Mmm, Have you try using a @transparency after the color?

Thanks for the tip Esteban82; I’ll try this!

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Strange, the transparency doesn’t seem to affect the psscale - it is plotted with no transparency.

Shouldn’t this give a bar with transparent colors?

gmt makecpt -A50 -Cturbo -T-4000/-1000/500 -D > temp-col
gmt psscale -Ctemp-col -R0/10/0/10 -JX10c -pdf temp-col

I think that is a “feature”, i.e., something that has not been implemented. There would also be some limitations on this. If you have a continuous colorbar and you have a section of it with transparency then we cannot do it - it would have to be all of them with a constant transparency. But discrete colorbars one can have some individual transparent colors, or all.

Please open an issue for a feature request to allow psscale to place transparent CPTs.

Understood. Thanks Paul. Will open an issue.

Esteban82: your suggestion was my solution. Paul just needed to implement the feature before I could use it!

This is a textbook example of how software development should be done. I continue to be amazed, but I shouldn’t be - I’ve experiencedd it over and over again.

Great work!!