Worked on stabilizing shader code within the playcanvas/engine repository, focusing on resolving rendering errors caused by duplicate camera_params uniform definitions. Addressed this issue by implementing a preprocessor guard in GLSL, ensuring that camera_params is only declared when CAMERAPLANES is not already defined. This targeted fix improved the reliability and stability of the pickPS shader path, reducing platform-specific failures and user-visible glitches. The work demonstrated a strong grasp of graphics programming and shader programming, enhancing the maintainability of the rendering pipeline and minimizing future defect risks by introducing robust guard logic into the shader codebase during the development period.