Ray-tracing is a classic example of an embarrassingly parallel algorithm; since each pixel is typically independent of the rest, theoretically every pixel can be done in parallel (given enough core
The N-Body problem is a classic example used frequently to demonstrate parallelization and how it improves performance.
Several authors from DreamWorks Animation, Pixar, Side Effects, AMD and Intel got together to write a book based on the Siggraph 2013 course on Multithreading in Visual Effects.
General Matrix Multiply
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