[osg-users] VBO questions

[Robert Osfield]

Hi Terry,

On 3 May 2015 at 07:11, Terry Welsh <mogumbo at gmail.com> wrote:
> A couple questions about OSG exposing specific VBO features:
>
> Looking at the body of DrawElementsUInt::draw(), it appears the size
> of its base std::vector is directly used for the elements count. I'm
> doing dynamic geometry and usually want to draw fewer elements. Is
> there a way to do this with OSG's API?

The core OSG doesn't support this, you could subclass from
DrawElements to implement a custom apply method that has a user
defined number of elements.


> Right now I'm using Geometry::setVertexArray() and
> Geometry::setNormalArray(), but I'd like to see if I can get better
> performance from an interleaved array. Is there a way to do this?
> Perhaps some example code somewhere?

Again the core OSG doesn't support it, so you'd need to subclass from
osg::Drawable and implement the OpenGL calls for the interleaved
array.

Robert.