I am able to style the colors of a geology polygon shapefile according to the Red, Green and Blue fields of the attribute table using data defined override with the expression: "color_rgb("RED" , "GREEN" , "BLUE")", which works great and the colors on the map canvas render properly. However the colors in the legend symbols are totally random and don't correspond to the colors on the map. I see a similar issue used to arise where the legend symbols were all black in older versions of QGIS...

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  • The random colors you see are the ones assigned by the categorized renderer. They have nothing to do with the data-defined settings.
    – underdark
    Commented Jun 6, 2017 at 17:41
  • So basically I'm out of luck until the feature request is implemented? Commented Jun 6, 2017 at 21:40
  • The best option might be a user-driven funding round to get this feature implemented. But someone has to be the driver for such an effort.
    – underdark
    Commented Jun 7, 2017 at 16:17


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