I too feel this is a major missing piece of functionality in QGIS. I often
work with large vegetation and landcover rasters, and while it is possible
to work with them in QGIS, it seems much more laborious than it needs to be.
I entered a related ticket on this issue last year
My take was slightly different, I was suggesting that there be support for
raster attribute tables that come with many of these datasets, especially
when they are in ERDAS Imagine img files. These attribute tables often
include important data like vegetation type, vegetation complex, etc. If the
table could be accessed you would then open the dataset up for both
attribute queries and styling. These attribute columns could be made
available to style the raster via the Categorized or Rule based renderers.
For example, a vegetation dataset could be brought in and styled by the
vegetation type attribute column. Or groups of vegetation/landcover types
could be assigned the same color with the Rule based renderer.
However, your solution may be easier to implement. It would be a major
improvement to the software
in my humble opinion :)
Kurt Menke, GISP
Birds Eye View
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