Bullet Physics - btConvexShape to Softbody

Question

I have a simple question: How do I convert a btConvexShape to a btSoftBody? By using btSoftBodyHelpers::CreateFromConvexHull? If so, I'm not clear on how I pass the convex hull to the softbody helper based on bullets documentation for the helper and convex shape

Answer 1

btConvexShape can be any convex object in bullet, not just a convex hull. You should implement different approaches depending on the concrete subclass. Use btCollisionShape::getShapeType() (return values) to find out the concrete implementation, then cast. Eg:

btSoftBody* convexShapeToSoft(const btConvexShape& shape)
{
    if(shape.getShapeType() == BOX_SHAPE_PROXYTYPE)
    {
        const btBoxShape& boxShape = static_cast<const btBoxShape&>(shape);

        // Build btSoftBody using the box vertices
    }
    else if(shape.getShapeType() == SPHERE_SHAPE_PROXYTYPE)
    {
        const btSphereShape& shpereShape = static_cast<const btSphereShape&>(shape);

        // Build btSoftBody using the box vertices
    }
    // ....
}