QwtRasterData::value(...) returns a value for all x/y positions inside the bounding rectangle. This is how it is defined - otherwise your implementation is insufficient.
A QwtRasterData object that sits on a 2 dimensional array always has to do an internal resampling ( in most cases simply next neighbour ) because the pixel positions never meet the raster.
Uwe
Hmmm, I lost my reply made yesterday...
From your internal resampling data, can I get back your resampled value at location (x, y)? If so, how?
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