Particles: Fixed thread work size calculation.
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Authored by Stefan Werner (swerner) on Jan 20 2021, 11:23 AM.

Details

Reviewers

Lukas Tönne (lukastoenne)
Brecht Van Lommel (brecht)

Commits

rBcde858ae98a5: Particles: Fixed thread work size calculation.
rB927d099ec099: Particles: Fixed thread work size calculation.
rBcdf564277c4d: Particles: Fixed thread work size calculation.

Summary

Dividing the workload by number of tasks in float is imprecise and
lead in some cases to particles not being calculated at all
(example: 20000 particles, 144 tasks).

Switching this calculation to integer makes sure we don't lose count.

Diff Detail

Repository: rB Blender

Event Timeline

Stefan Werner (swerner) requested review of this revision.Jan 20 2021, 11:23 AM

Stefan Werner (swerner) created this revision.

Harbormaster completed remote builds in B12290: Diff 32955.Jan 20 2021, 11:23 AM

Unfortunately, I do not have permission to provide my test scene.

I think this fix should also be included in 2.92 and 2.83LTS.

@Lukas Tönne (lukastoenne) I'm adding you as a reviewer since git tells me you wrote the code I'm changing here.

Stefan Werner (swerner) added a reviewer: Brecht Van Lommel (brecht).Jan 21 2021, 10:34 AM

Brecht Van Lommel (brecht) accepted this revision.Jan 21 2021, 4:48 PM

This revision is now accepted and ready to land.Jan 21 2021, 4:48 PM

Closed by commit rBcdf564277c4d: Particles: Fixed thread work size calculation. (authored by Stefan Werner (swerner)). · Explain WhyJan 22 2021, 9:22 AM

This revision was automatically updated to reflect the committed changes.

Stefan Werner (swerner) added a commit: rBcdf564277c4d: Particles: Fixed thread work size calculation..

Stefan Werner (swerner) added a commit: rB927d099ec099: Particles: Fixed thread work size calculation..Jan 22 2021, 9:30 AM

Ben Thery (oxben) added a subscriber: Ben Thery (oxben).Jan 22 2021, 6:58 PM

Ben Thery (oxben) added inline comments.

source/blender/blenkernel/intern/particle_system.c
479	Out of curiosity, why not use the modulo operator here ? int remainder = numtasks > 0 ? (endpart - startpart) % numtasks : 0;

Jeroen Bakker (jbakker) added a commit: rBcde858ae98a5: Particles: Fixed thread work size calculation..Jan 25 2021, 10:14 AM

Revision Contents
Changeset List

Path

Size

source/

blender/

blenkernel/

intern/

particle_system.c

20 lines

Diff 33018

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source/blender/blenkernel/intern/particle_system.c

Particles: Fixed thread work size calculation.ClosedPublicActions