I have made a special 3D engine that use only the CPU and I have a performance issue (below 10 fps for min graphics element required).
by Jeff Andrews
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.
I am casting a large number of rays from a compact ray-casting source into a static geometry scene. This is not for rendering. The geometry may have a very large # of triangles.
Particle systems are an ideal candidate for multi-threading in games. Most games have particle systems and their general nature of independent entities lends well to parallelism.
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