Concatenate your model from thousands of distinct elements to one unique GameObject with a single material, to drastically reduce draw calls. 

The Combine function creates one mesh with one baked material from a set of different meshes with different materials assigned. It will not produce any geometric changes. The original UV are preserved but repacked into a new unified texture atlas.

WARNING        Combine Mesh is rather a long function. Please expect a long execution with large input.

NOTE                Combine Mesh has been tested and validated through optimization processes containing meshes with standard materials.