Transforms a world position and size (in world units) to their equivalent local position and size on given panel, using provided camera for internal WorldToScreen transformation. <param name="panel">The local coordinates reference panel.</param> <param name="worldPosition">The world position to transform.</param> <param name="worldSize">The world size to transform. The object in the panel will appear to have that size when compared to other 3D objects at neighboring positions.</param> <param name="camera">The Camera used for internal WorldToScreen transformation.</param> <returns>A (position, size) Rect in panel coordinates that corresponds to the provided world position and size.</returns>