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Nodes->grid surfaces
To create a grid of surfaces from a cloud of 3D nodes. The user will be asked for the cell size
The z of the grid will be extrapolated averaging a collection neighbor nodes.
If the checkbox "Far points set nodata" is set, then grid points further of the distance specified will be set to a special nodata value (-9999 usually) , and won't generate grid surfaces
Triangles->grid surfaces
To create a grid of surfaces from a cloud of 3D triangles. The user will be asked for the cell size
The z of the grid will be get from the triangle where the grid corner is projected (in 2D), or from a close node.
If the checkbox "Far points set nodata" is set, then grid points outside the triangles will be set to a special nodata value (-9999 usually) , and won't generate grid surfaces