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wh1sp3rik
11-15-2009, 08:47 AM
Hello,
I am trying make terrain LOD using glDrawElements and VBO.
I am rendering 4096x4096 terrain using 64x64 blocks (64x64 polys).

LOD1 has 24576 indices
LOD2 has 6906 indices
LOD3 has 2298 indices
LOD4 has 3444 and that's my problem.

I need to design terrain lod. This image shows LOD3 and LOD4
Image here (ftp://78.102.70.147/terrainlod.png)

I am using only triangles. perhaps, u can use triangle fans on borders, but i don't know, how make them in one buffer, in one element.

do you know about good site ? Do anybody have experience with terrains ? Thank you

pjcozzi
11-15-2009, 08:57 AM
do you know about good site?
The Virtual Terrain Project (http://vterrain.org/LOD/Papers/) has a wealth of information on terrain LOD.

Regards,
Patrick

Aleksandar
11-15-2009, 01:46 PM
Why the number of indices rises in LOD4, and why do you have so many triangles at the border of each block?

Except the request for the link to the site, do you have any concrete question?

You cannot combine different primitives in one drawing call, but nothing prevents you to draw it in several calls, if you find it suitable. On the first glance I don't recognize the pattern that could enable drawing border in just one call, so each block requires 24 fans. Consider revision of your LOD scheme.