Computing bounding box/sphere with index drawRange

I’ve using ‘setDrawRange’ for generating multiple submeshes with sharing same vertex/index buffer. There’s no problem in rendering submeshes and control visibility. But when computing bounding box/spehre with ‘computeBoundingBox’ and ‘computeBoundingSphere’ function, all the submesh’s bounding box is the same, including all the vertices in the vertexbuffer. This compute bounding box and sphere functions do not consider the draw range setup for geometry.

Like this image, I want to render one submesh with setDrawRange on geometry. But ‘computeBoundingBox’ function could calculate the region for all the geometry vertices, could not reduce excluded vertices.

Couldn’t you consider the draw range setting when compute bounding box or sphere with extending implementation. (or with optional api) Surely, I can implement customized compute bounding region function but it could make hesitating with existing api function calls.

(I’m using three.js r152.2. If you already resolve this issue in some higher version of three.js, please let me know about that.)

This feature isn’t implemented even in the latest version. Here is the respective issue at GitHub: