[Plib-users] Need advices to use Plib for a Roam algo

[Maltez <ma...@no...>]

HI
I have implemented a terrain engine with a ROAM like algo. It's all =
coded from scratch using Opengl with Glut and without a scene graph =
hierarchy of classes.
I am evaluating to use a scene graph toolkit to port my engine and the =
add other functionality like sky, tree,... with Plib.
Plib seems to be very lightweight but powerfull and let a clear access =
to OpenGl. Such small and clever thin toolkit i like.

I'm new to Plib and i would like to have some advices to make the right =
(or not too wrong) use of Plib classes and right use of sub-classing =
shema.
My current architecture is as usual : a manager class containing a grid =
of 10x10 tiles each containing 2 bintrees. The manager class refine the =
mesh with splits/merges when the camera frustrum change in a method =
Update(). The Render() method feeds arrays of =
vertices/normal/texcoord/colors for each tile and then draw them with a =
glDrawElements() call.

Now the dumb questions :
- Is it correct to subclass the ssgBranch class to implement my tile =
manager class and subclass the ssgVtxArray for my tiles class ?
- another approach seems to use the predraw callback on a ssgBranch =
containing ssgVtxArray and doing all the work in my manager and tile =
classes (which will not be subclasses of ssgBranch and ssgVtxTable) ? in =
that case how to get the frustrum i need to the cull the triangles ?
- i plan to share one instance of ssgVertexArray, ssgNormalArray,... for =
all the ssgVtxArray tiles and a refresh the vertices before each draw of =
each tile. Is there some pitfall with that ?
- how to skip the culled out tile in the cull (and draw) traversal ?
- another approach is put all in a fresh new subclass of ssgLeaf (and no =
use of ssgVtxArray or ssgBranch). What about this technic ?=20

I would be glad to have some advices, critics or ideas to use Plib for =
my Roam engine.
Thanks