How do you reduce draw calls in 3D rendering for improved performance?

To reduce draw calls in 3D rendering for improved performance, key methods include mesh combining, instancing, and texture atlases. Draw calls are commands from the CPU to the GPU; fewer calls reduce communication overhead, directly enhancing performance. Mesh combining merges small, separate meshes into larger ones, lowering the number of individual render commands. Instancing renders multiple identical objects (e.g., trees, particles) with a single call by reusing the same mesh data. Texture atlases pack multiple small textures into one large texture, minimizing state changes between draws. For scenes with repeated elements (e.g., game environments), instancing is often the most practical first step to effectively reduce draw calls.