Merge branch 'gdal_support_mask_band' of https://github.com/rouault/mapnik into rouault-gdal_support_mask_band

This commit is contained in:
artemp 2016-06-07 13:30:45 +02:00
commit 3f224e3f4d

View file

@ -551,6 +551,32 @@ feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
MAPNIK_LOG_WARN(gdal) << "warning: nodata value (" << raster_nodata << ") used to set transparency instead of alpha band";
}
}
else if( dataset_.GetRasterCount() > 0 && dataset_.GetRasterBand(1) )
{
// Check if we have a non-alpha mask band (for example a TIFF internal mask)
int flags = dataset_.GetRasterBand(1)->GetMaskFlags();
GDALRasterBand* mask = 0;
if (flags == GMF_PER_DATASET)
{
mask = dataset_.GetRasterBand(1)->GetMaskBand();
}
if (mask)
{
MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: found and processing mask band...";
if (!raster_has_nodata)
{
raster_io_error = mask->RasterIO(GF_Read, x_off, y_off, width, height, image.bytes() + 3,
image.width(), image.height(), GDT_Byte, 4, 4 * image.width());
if (raster_io_error == CE_Failure) {
throw datasource_exception(CPLGetLastErrorMsg());
}
}
else
{
MAPNIK_LOG_WARN(gdal) << "warning: nodata value (" << raster_nodata << ") used to set transparency instead of mask band";
}
}
}
mapnik::raster_ptr raster = std::make_shared<mapnik::raster>(intersect, image, filter_factor);
// set nodata value to be used in raster colorizer
if (nodata_value_) raster->set_nodata(*nodata_value_);