Reduced render time for bars by 60-80%, by caching IsSpatial #5026
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In my profiling, GetSpatialColor represents 33% of the time spent inside BarsEffect::Render, just checking buffer.palette.IsSpatial(colorIdx) for every pixel. If you're not using spatial colors, this time is pure wastage. The optimiser can't see deep enough to know that it can cache IsSpatial, so I've done it manually. Despite expecting a saving of only 33%, it's actually more like 60%, because skipping the GetSpatialColor function call also skips all of the maths done to build its parameters, such as `(float)x / (float)buffer.BufferWi`, and `(float)(n % barHt) / (float)barHt`. 5.878s -> 2.184s for my test sequence, that is one bars effect with 3 colours, across all channels. More savings could undoubtedly be had by performing this same optimisation on other effects.
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Build failure is unrelated to PR; looks like 602444a is the cause. |
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In my profiling,
GetSpatialColorrepresents 33% of the time spent insideBarsEffect::Render, just checkingbuffer.palette.IsSpatial(colorIdx)for every pixel. If you're not using spatial colors, this time is pure wastage. The optimiser can't see deep enough to know that it can cacheIsSpatial, so I've done it manually. Despite expecting a saving of only 33%, it's actually more like 60%, because skipping theGetSpatialColorfunction call also skips all of the maths done to build its parameters, such as(float)x / (float)buffer.BufferWi, and(float)(n % barHt) / (float)barHt.5.878s -> 2.184s for my test sequence, that is one bars effect with 3 colours, across all channels.
More savings could undoubtedly be had by performing this same optimisation on other effects.