Question 1 (a) Appraise the use of ray-tracing in computer graphics. How is ray-tracing different from normal OpenGL rendering? How have advancements in modern Graphics Processing Units contributed greatly towards ray-tracing? (12 marks) (b) When not using ray-tracing, illustrate what difficulties exist when achieving physically perfect results when rendering semi-transparent or translucent surfaces. How would you go about dealing with the issues? Discuss and show examples.