CMPS-3480 Computer Graphics

Lab-4 notes

Several things can go wrong in lab-4 when working with barycentric coordinates.

1. The area of a triangle might be zero. But due to how floating-point numbers
   are handled by the processor, the area might be negative zero.

   This will cause the square-root function to produce a NaN error result.

   sqrt(0) = 0

   sqrt(-0) = NaN ERROR

   An aceptable way to handle this in our lab4 program is to check triangle
   area, and if negative, set it to zero.


2. Barycentric coordinates might be invalid.

   When calling the getBarycentric function, always check the return value
   and make sure it is TRUE.

   If not TRUE, then do not use those u, v, w values. Skip them.