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2

This code works for creating an OGRDataSource. Special thanks to Michael Miles-Stimson for getting me on the right track. const char* path = "C:/Test/test.shp"; OGRRegisterAll(); OGRDataSource *hDS; OGRSFDriver *driver; OGRSFDriverRegistrar *registrar = OGRSFDriverRegistrar::GetRegistrar(); driver = registrar->GetDriverByName("ESRI Shapefile"); hDS = ...


3

You're trying to use an OGR (vector) driver with GDAL (raster) tools. Here's a few lines of my working code that may help: char* BasePath = new char[FullPathMax]; // this does have a value before it's used OGRRegisterAll(); OGRDataSource *hDS = NULL; OGRSFDriver *Driver = NULL; hDS = OGRSFDriverRegistrar::Open(BasePath,FALSE,&Driver); As you can ...


0

So I think the answer is effectively no. You can't get a percent shaded from a hillshade. You can get an estimated shadowed mask. The confusing bit here is that unlike the description here gdaldem hillshade outputs 1 instead of 0 for shaded tiles. Postgis's ST_Hillshade outputs 0 but takes around 20 seconds on my system version 0.5 seconds.


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You can use gdal_calc.py see: http://www.gdal.org/gdal_calc.html if your mask is a raster of same dimension gdal_calc.py -A input.tif -B mask.tif --A_band=3 --B_band=3 --outfile=result.tif --calc="A*B" That will multiply each cell of the raster with the corresponding cell of the mask. Where the mask cell is 0,0,0 the output cell will be 0,0,0 and where ...


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Yes you can show features that evolve during a time period. I would suggest you to have a look into Anita Graser's Time Manager plugin to see if it does what you need: https://plugins.qgis.org/plugins/timemanager/ you can also check this video: https://www.youtube.com/watch?v=GkfoFFy-bao Then, since it's Open Source we are talking about, check it's code ...


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I don't know about the API, but when you add a delimited text layer you can set 'watch layer' in the layer settings. File changes are only visualised when the QGIS view is refreshed in some way (pan, zoom, etc).



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