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    // Example shader optimization tips for mobile XR:
    // 1. Minimize the number of texture samples.
    // 2. Use lower precision data types (e.g., half instead of float).
    // 3. Avoid complex mathematical operations and loops.
    // 4. Use baked lighting where possible to reduce real-time calculations.
    // 5. Implement LOD (Level of Detail) for materials and shaders.
    // 6. Utilize GPU instancing for repeated objects.
    // 7. Profile shader performance using tools like Unity's Frame Debugger.
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