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POV-Ray / povray

The Persistence of Vision Raytracer: http://www.povray.org/
GNU Affero General Public License v3.0
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Speed up loading uncompressed bmp files #397

Open mlsomers opened 4 years ago

mlsomers commented 4 years ago

Improved the speed of loading standard 24bit BMP files (and 32bit with alpha).

Instead of reading one byte at a time, reading a whole line at a time reduces allot of "context switching". On my (slow) machine it reduced loading time from 8 minutes down to 2 minutes! (my machine is heavily swapping memory while doing the test).

mlsomers commented 4 years ago

yikes! why is this not separated from my previous pull request? It should only include the file bmp.cpp. The rest is for caching!

mlsomers commented 4 years ago

Reverted all changes related to the other pull request. Also moved conditional alpha outside the nested loops (gain was not significant).