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Hi!

I'm trying to create heightmaps (Grayscale PNG raster based on elevation/z-value) from multiple point clouds that make up a very large area.

It can be done by combining all the point clouds with the PointcloudCombiner and then use the RasterDEMGenerator to create a large raster. This can then be clipped into smaller rasters of the desired size. However, creating the raster takes an increasingly long time (several days) when the raster becomes very large.

Because of this I instead created a raster from each separate point cloud (and in smaller combined point clouds) and then merged them into a big raster before clipping them into the desired sizes. This was insanely much faster. However, I came across a new issue. When creating a raster from the separate point clouds, the values around the edges are not consistent with the rest of the point cloud, which creates and edge along the border of the raster. When merged together, they can be seen as lines that make out the separate rasters generated.

Does anybody have a solution to adress this?

Images showing the issue:

Hi @antonlarsson,

The RasterDEMGenerator uses triangulation to create a TIN before generating the new raster DEM, and triangulation can be inconsistent at the edge of the model. My usual solution is to ensure that the extents of the input points is 5-10% larger than the final desired raster DEM (or contours). You can do this by buffering the clip boundaries before clipping the input points, then clipping the output raster with the original boundaries.

Hi @antonlarsson,

The RasterDEMGenerator uses triangulation to create a TIN before generating the new raster DEM, and triangulation can be inconsistent at the edge of the model. My usual solution is to ensure that the extents of the input points is 5-10% larger than the final desired raster DEM (or contours). You can do this by buffering the clip boundaries before clipping the input points, then clipping the output raster with the original boundaries.

Thank you, this solved it perfectly!

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