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2D Level of Detail (LOD) Algorithm

I researched the network for an algorithm that allows you to create levels of detail (LOD) of 2D polygon representations, but I can’t find ANY decent help. I may be using the wrong search terms, but all the search results for 3D LOD algorithms that I think cannot (?) Really apply in 2D.

I am sure that before the onset of 3D graphics, many people worked on 2D LOD algorithms. Any tips or pointers to where I can get more information? Thank!

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Besides the obvious stupidest algorithm, which was to take every Nth vertex from the polygon (reducing the number of vertices by N), here is an idea inspired by some 3D algorithms.

Usually in 3D, you want to remove faces that make a smaller contribution to the total. To do this, we are trying to simplify the “flattest” areas of the model.

Now in 2D you can translate this to “simplify the segments that have the smallest angle between them. The first naive implementation could be:

  • Calculate all angles between segments of Si and Si + 1 polygon
  • Take all angles below a given threshold (or take the M smallest angles)
  • Simplify the segments identified in 2. (replace [Pi, Pi + 1] and [Pi + 1, Pi + 2] with [Pi, Pi + 2])
  • Repeat from 1. until we reduce our polygon

, , . (Pi + 1) ([Pi, Pi + 2])

:

, , :

  • Catmull-Rom
  • Tesselate

, : http://motiondraw.com/md/as_samples/t/LineGeneralization/demo.html, : http://www.geom.unimelb.edu.au/gisweb/LGmodule/LGSimplification.htm

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