The goal here is to compare 3Delight's OSL rendering core with other renderers using C++ for for shading (namely Arnold and RenderMan/RIS). Since all renderers are quite different, we will try to get to a most common denominator, in terms of setup, to be able to compare apples to apples. We want to know: can we go as fast, in OSL, as highly optimized C++ ray-tracer ? How does OSL compare to our optimized RSL SIMD just-in-time compiler ?
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- We will just use diffuse reflectors.
- We will disable any adaptive sampling so to make sure we have very close ray-counts.
- We will use only one diffuse bounce. This will circumvent some complex variables from the equation (Russian roulette and other tricks of the trade). When looking at the statistics, all renders have a path length of 3.
- The scene is easy to load, setup and render. It is available for all tested renderers.
All renders are done in Maya 2015 Extension 1.
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We will be testing the wall clock time for all renderers. Every renderer will be run 3 times in succession and the average time will be taken. We make sure that nothing is running on the machines machine so not to slow down the poor renderers. The render is launched from Maya 2015 Extension 1. We are using a mid level Linux machine for our tests :
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- We use non-normalized area lights. This is because 3Delight OSL doesn't support normalized lights yet.
- There is a slight difference in tint between Arnold and 3Delight. We think it's due to differences in color management between the two renderers
- RenderMan/RIS area lights sources had to be set with higher intensity. We are unsure why.
- RenderMan/RIS has very different diffuse lighting component. Again, we are unsure why. One hint might be how the shading normals are treated
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