1. A computer program product for use in connection with a computer to provide a computer graphics system for generating a pixel value for a pixel in an image, the pixel being representative of a point in a scene, the computer graphics system generating the pixel value to provide a soft shadow that is represented by an evaluation of an integral of a selected function over a finite extent of a light source, the computer program product comprising a computer-readable medium having encoded thereon: A. computer-readable instructions executable to enable the computer to provide a sample point generator for generating a set of sample points representing points on the finite extent of the light source, the sample point generator using a predetermined strictly-deterministic low-discrepancy sequence to generate the sample points; B. computer-readable instructions executable to enable the computer to provide a function evaluator for generating a plurality of function values each representing an evaluation of said selected function at one of the sample points generated by said sample point generator; C. computer-readable instructions executable to enable the computer to provide an illumination value generator for generating an illumination level value for the point in the scene as the average of said function values generated by said function evaluator, and D. computer-readable instructions executable to enable the computer to provide a pixel value generator for using the illumination level value generated for the point in the scene in generating the pixel value.