Starting data

The starting data is the file 'topo_nlc.dat', that is a text file with xyz of a grid (5800 points)

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A common graphical problems is that topographic models are mapped from the curved earth to a planar representation with UTM projection and this could become in too big x,y 2D coordinates (model box far from the origin). This is a graphic problem drawing with OpenGL that uses float real numbers for coordinates (about 7-8 significant digits). Staircase graphical artifacts, and the selection in screen could become a little displaced of the entity drawn. An easy solution is to translate the model in XY near the origin.

How to create a surface model?

The model has only points, not surfaces. There are different ways to create surfaces

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