Spring 2009 CSG140 Computer Graphics

Assignment 1

Professor Harriet Fell


In this assignment, you will generate a realistic image of a 3-dimensional scene composed of spheres floating between you and the view plane. You will use ray-tracing and a local illumination model to generate your image.

General description

Develop your program in five stages.

  1. Generate a flat image using only ambient light. This way you will know that your program is finding the spheres before you go on to work on shading and shadows.

  2. Add shading to your image using Lambert's Law for diffuse lighting.

  3. Add shadows cast on the spheres by following a ray from a visible point on a sphere to the light source.

  4. Add Phong highlights on the spheres.
  5. Make the viewplane visible (i,e, not black) and add shadows cast on the view plane by following a ray from each visible back-plane pixel to the light source.

See Building a Ray Tracer - Page One for sample images. Note that the small images on that page are links to larger images.


By midnight Thursday, January 29, 2009.


These grading guidelines will be used for all programming assignments:
Your project will be graded on:

Some points may be subtracted (up to 10%) if you need substantial help from the professor to make your program run.

The penalty for a late homework is 5% per calendar day for up to one week late.
No homework will be accepted later than that.

Turn in:

Harriet Fell
College of Computer Science, Northeastern University
360 Huntington Avenue #202WVH,
Boston, MA 02115
email: fell@ccs.neu.edu
Phone: (617) 373-2198 / Fax: (617) 373-5121

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