How do I query accelerate the triangles from a StaticMesh?

[Spankenstein]

I usually use:

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Space.BroadPhase.QueryAccelerator.GetEntries

to obtain all the entities that intersect a bounding sphere.

How can I do the same thing but with the triangles of a StaticMesh without have to test against all the triangles in the mesh (i.e. using a built in "accelerator")?

[Norbo]

This would work:

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if(staticMesh.Mesh.Tree.GetOverlaps(boundingShape, overlapsList))
{
      //Do stuff
}

StaticMeshes are special amongst meshes in that they have a world space hierarchy which can be queried directly. Other meshes, like the Terrain and InstancedMesh, have local space hierarchies. Querying them is a little trickier, but still possible.

[Spankenstein]

Thanks Norbo. Here's what I've done:

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                    List<int> triangleIndices = new List<int>();
                    
                    // Test for overlapping triangles in the static mesh
                    StaticMesh mesh = c as StaticMesh;
                    mesh.Mesh.Tree.GetOverlaps(boundingSphere, triangleIndices);

                    Vector3 vertexA;
                    Vector3 vertexB;
                    Vector3 vertexC;

                    int numIntersected = triangleIndices.Count;

                    for (int t = 0; t < numIntersected; ++t)
                    {
                        mesh.Mesh.Tree.TriangleMeshData.GetTriangle(triangleIndices[t], out vertexA, out vertexB, out vertexC);
                        triangles[numTriangles++] = new Triangle(vertexA, vertexC, vertexB);
                    }