How do game engines like Unity and Unreal Engine handle 3D model integration?

Game engines like Unity and Unreal Engine handle 3D model integration through a streamlined pipeline of import, optimization, and scene integration. Import: They support standard 3D file formats (e.g., FBX, OBJ, glTF) from tools like Blender or Maya, converting files to engine-compatible formats for rendering, physics, and animation systems. Optimization: Adjust polygon counts, bake textures, or set up skeletal rigs to balance visual quality and performance, ensuring models run smoothly on target hardware. Scene integration: Models are placed into scenes, with engines managing lighting, material application, and real-time interactions to merge them into the game environment. For complex models, start with simplified versions to avoid performance issues during integration.