Curves & Surfaces

  1. How can a parametric equation of a surface be used to render that surface in a system like OpenGL
  2. Derive the parametric equation of a sphere?
  3. What is a ruled surface? Give an example.
  4. Derive a parametric equation in two variables for a sphere of radius R centered at the origin    
  5. Derive a parametric equation in two variables for a Torus centred at the origin whose Outer radius is R and Inner radius is r.
  6. Describe an algorithm for building a polygon mesh using the explicit method for a sphere.       
  7. Write a detailed note about Bezier curves. How would you represent them parametrically?      
  8. Describe Bezier curves in terms of their properties, advantages and disadvantages
  9. With respect to Bezier curves, what is “end-point interpolation”?
  10. Why does a Bezier curve always say inside it’s convex hull?
  11. What is the role of the Blending function in Bezier curves.
  12. Given a curve, p(t), defined on the x-z plane, describe how you would rotate it around z-axis to generate a volume of rotation. Show the parametric equation for the resulting shape. How can this equation be used to build a polygon mesh.
  13. Describe (geometrically) how a Bezier curve of 3 control points is generated.
  14. How is this extended to n-control points.
  15. How is the general Bezier curve described parametrically.
  16.  A Bezier curve is defined by the following control points; {(1,1), (2,2), (3,2)}. Find the location of the curve at t=0.5.