how to reduce sawtooth of polyline in osgearth2.7?

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ldj ldj
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how to reduce sawtooth of polyline in osgearth2.7?

gwaldron gwaldron
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Re: how to reduce sawtooth of polyline in osgearth2.7?

ldj,
This is a side-effect of the draping algorithm, which uses projective texturing to render the geometry as a terrain overlay. Someday we would like to create a better algorithm, perhaps one that uses cascades, but for now this is the best you can do.
Glenn Waldron / Pelican Mapping
ldj ldj
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Re: how to reduce sawtooth of polyline in osgearth2.7?

hi gwaldron :
cascades  means what?, as possible as detailed.
gwaldron gwaldron
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Re: how to reduce sawtooth of polyline in osgearth2.7?

The problem with projective texturing is that it stretches a single texture over a large area of terrain. That is why you get the aliasing artifact. A possible position would be to use multiple textures where the first is close to the camera, the second is farther away, and so on. This is similar to the approach used to implement Cascading Shadow Maps (CMS) for shadowing.
Glenn Waldron / Pelican Mapping
ldj ldj
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Re: how to reduce sawtooth of polyline in osgearth2.7?

gwaldron
  hi,   the single texture  is 4096*4096?