Hi, Just wanted to mention a new capability of the VRT driver (https://github.com/OSGeo/gdal/pull/3303) to take into account the mask band of a source to determine which pixels must be taken into account. This is a generalization of the <NODATA> mechanism to the mask band concept. This can work with internal/external mask bands, and with alpha band too, with the limitation for the later that it will interpret any non-0 value as fully opaque (no alpha blending)
I was hesitating a bit if that new capability should be implicit or explicit. I decided for explicit, to be consistent with the existing NODATA mechanism. That said, if you create the VRT with gdalbuildvrt, it will default to using the new feature and adding the required <UseMaskBand>true</UseMaskBand> element. Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/gdal-dev
