Re: [Plib-users] <<code review>> Bounding sphere of a branch node

[Steve B. <sjb...@ai...>]

Steve Baker wrote:

> > But think about a scenario where a Branch group has a
> > leaf ssgRahulLeaf which is derived from ssgLeaf and
> > has a different constrcutor which does not invoke
> > recalcBSphere in it. Also imagine that the user of the
> > ssg API did not call flatten on the scene graph before
> > renedering it. Will the bounding spheres of the branch
> > nodes be updated in this case ?

Oops - missed that comment.

If you fail to tell ssgRahulLeaf to do a recalcBSphere
then the leaf node's bsphere will not have been computed,
and (in theory) the first time the node is called upon to
getBSphere, it *should* be computed.  That will typically
happen the first time the scene graph is rendered.

I noticed though that ssgEntity (the base class for all
scene graph nodes) does not dirty the sphere in its
constructor function - so if you really did do that,
things would be a little undefined.

I just fixed that by setting invalidBSphere TRUE in
the ssgEntity constructor.

-- 
Steve Baker                  http://web2.airmail.net/sjbaker1
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