GetVirtualHeightMapInBBox does not work when DEMFileRegistrationMode is Cell

[g0ro]

Trying to get heightmap in bbox, using GeoTiff dataset with Cell file format, fails when bbox is partially covered.

RasterService.GetVirtualHeightMapInBBox(...) returns a hightmap half pixel shifted. This results in incorrect height map when merging tilesHeightMap in ElevationService.GetHeightMap(....)

When DEMFileRegistrationMode is Cell, we should add (metadata.pixelSizeY / 2d) to metadata.DataEndLat, and (metadata.pixelSizeX / 2d) to metadata.DataStartLon
(File:

DEM.Net/DEM.Net.Core/Services/Raster/RasterService.cs

Line 560 in 168cd8e

double latitude = metadata.DataEndLat + (metadata.pixelSizeY * y);

, Lines: 560, 566, 567, 576)
Reference:

DEM.Net/DEM.Net.Core/IO/Raster/GeoTiff.cs

Line 440 in 168cd8e

double endLat = metadata.DataEndLat + metadata.pixelSizeY / 2d;

[xfischer]

Hi @g0ro, thanks for reporting this. Can you submit a PR ?