[Plib-users] Pre/Post draw callbacks on ssgBranches.

[Jon A. <jan...@on...>]

Hi,

I've been working on a really simple implementation of ROAM to work with 
SSG.  It's split into two parts, a terrain class, and a patch class. Each 
patch is just a subset of the terrain, to facilitate frustum culling. Each 
frame, the terrain class initializes, and then tessellates each of its 
patches.  After all have been tessellated, it then renders them.  It 
tessellates them all at once so that it can match edges, and avoid cracks 
in the terrain.

I've implemented the terrain class as an ssgBranch class, and the patches. 
But any pre or post callbacks don't get called on branches.  It seems like 
they only get called on leafs.  So I have to activate the tessellating 
outside of the normal ssgCullAndDraw().  This isn't so bad, except it means 
no culling is done prior to tessellation.

Does anybody have any suggestions on  how to go about this?  Also, has 
anybody every tried to integrate any higherlevel organization like 
quadtrees or octrees into SSG?

Jon