Coloring surface by predefined RGB values

Dear All,

I have a surface on which I have RBG values stored in each cell. I am trying to see color defined by those RGB values. But I cannot figure out how to do it, or if this is possible to do it at all.
I would appreciate help a lot.

Thank you.

Uncheck MapScalars

Dear Mathieu,

Thanks for suggestion. I have 3D terrain on which I want to show Google Map photo. So I interpolate RGB values in my cells on the ground but do not know how to get a color out of it since Paraview reads these values as variable. I hope I managed to explain it.

That still sounds like the unchecking of the Map Scalars feature that @mwestphal suggested. In case you did not see that feature, here is a screenshot showing that checkbox.

If that is not the feature you’re looking for, you may need to explain further. It helps to post example data that we can load in ParaView and/or images of what you are getting and an example of what you would like to see.

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Dear Kenneth,
Here is the file. You will see the R G B values defined in the list of variables. They can be open separately but not jointly which would give a right color to the surface.

https://mega.nz/file/i8NikL5b#yUFcSsUQwi0TxPSZHQuHGkE7WILOVEzldmAFwAnenPY

Here you can see Paraview visualization of just B values out of three RGB values, and Tecplot visualization of RGB. I would like to get in Paraview the same colors as in Tecplot.

You have to combine the R color, G color, and B color fields into a single vector field. The easiest way to do that is to use the Calculator filter. The Calculator filter expression can convert a scalar to a 3D vector by multiplying it by iHat, jHat, or kHat, which represent the 3 unit axis vectors. You also need to divide the result by 255 because Calculator creates floating point fields, and floating point colors have to have the range of [0,1] instead of [0,255].

In all, the expression you want for the calculator is (R color*iHat + G color*jHat + B color*kHat)/255.

Here is a state file that properly shows the colors: color-terrain.pvsm (280.6 KB)

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Dear Kenneth,

I works perfectly. I cannot thank you enough. I would hug you even risking corona infection (well I was infected :smile: a month ago).
Thanks again. All the best.
Muhamed.