Hello,
I am trying to load NOAA raster charts into the background of QwtPlot. I used GDAL to read the charts to create a geotiff file, so let's say I have a geotiff chart with dimensions roughly 12,000 by 8,000.
I was thinking about using GDAL_translate to crop according to geospatial coordinates (-projwin option) and to resample according to number of pixels and lines (-outsize option) to create an image (bitmap). This is done whenever the user pans or zooms the plot, and then I would load the generated image (bitmap) in my QwtPlotItem to draw the background.
However, then I saw the QwtRasterItem class and thought that I would be able to load the whole 12,000 by 8,000 geotiff (converted to bitmap) into a rasterData and let the rasterItem automatically re-sample and draw the background.
Is this approach possible? And has anyone else ever had experience loading a huge background image and then resampling for the zoom/pan?
Thank you
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