Chapter 6: Hidden Surfaces

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Questions

1. Define the hidden surface problem.

   (Appeared in: 2009, 2010, 2013, 2015, 2017, 2019, 2021)

2. Why are hidden surface algorithms needed?

   (Appeared in: 2009)

3. Write down the z-buffer algorithm.

   (Appeared in: 2010, 2014, 2016, 2018, 2020)

4. How does the z-buffer algorithm determine which surface is hidden?

   Or, Describe the z-buffer algorithm for removing hidden surfaces from pictures.

   (Appeared in: 2009, 2015, 2017, 2021)

   Or, Name and describe an efficient algorithm used to overcome the hidden surface problem.

5. Why is it called the Z-buffer algorithm?

   (Appeared in: 2013)

6. What is coherence? Explain the different types of coherence.

   (Appeared in: 2016)

7. Given points P1(1,2,0),P2(3,6,20),P3(2,4,6)P_1(1, 2, 0), P_2(3, 6, 20), P_3(2, 4, 6) & a viewpoint C(0,0,10)C(0, 0, 10), determine which points obscure the others when viewed from CC.

   (Appeared in: 2014, 2019)

8. What is ray tracing?

   (Appeared in: 2010, 2015, 2017)

9. How are visible surfaces determined using ray tracing algorithms?

   (Appeared in: 2013)

10. What kinds of problems do we face in the hidden surface problem?

11. Discuss Painter’s algorithm for visible surface determination.

    (Appeared in: 2021)

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Let me know if further refinements are needed!