PhysicsProject
ActivePublic

Details

Description

Physics simulation systems including rigid bodies, cloth, softbodies, smoke fluids and particles.

Developers

Bullet: @Erwin Coumans (erwin)
Rigid Body: @Sergej Reich (sergof)
Cloth: @Daniel Genrich (genscher)
Smoke: @Miika Hamalainen (miikah) @Daniel Genrich (genscher)
Fluids: @Daniel Genrich (genscher) @Nils Thuerey (n_t)
Particles: @Janne Karhu (jhk) @Lukas Toenne (lukastoenne)
Softbody: @Jens Ole Wund(bjornmose) (bjornmose)

Recent Activity

Today

Campbell Barton (campbellbarton) requested changes to D2948: T50630: Fixed Windows fluid simulation with Unicode characters in path.

I don't have access to Win32 at the moment, P576 @João Esteves (Joao611), could you check if this works?

Thu, Dec 14, 1:50 AM · Physics, BF Blender

Yesterday

Campbell Barton (campbellbarton) accepted D2948: T50630: Fixed Windows fluid simulation with Unicode characters in path.

Nice fix but uses bad level calls, think we can use defines in CMake to pass in gzopen overrides.

Wed, Dec 13, 12:42 PM · Physics, BF Blender

Fri, Dec 8

João Esteves (Joao611) added a reviewer for D2948: T50630: Fixed Windows fluid simulation with Unicode characters in path: BF Blender.
Fri, Dec 8, 10:06 PM · Physics, BF Blender

Thu, Dec 7

ronan ducluzeau (zeauro) added a comment to T53472: Cycles doesn't render smoke properly with adjusted clipping distances.

There is no plan that goes into details for refactoring of smokes or a developer currently working on it for first 2.8. A refactoring of modifiers is expected for the end of 2.8 series but to convert modifiers's stack into modifiers nodes. Addition of an OpenVDB primitive can be done next year or more years later.

Thu, Dec 7, 12:34 PM · Rendering, Physics, Cycles, BF Blender
Felix (BlenderSpot) added a comment to T53472: Cycles doesn't render smoke properly with adjusted clipping distances.

@ronan ducluzeau (zeauro)
Thanks for the workaround but the thing is that I need to render like 20 slices along Z and 10 on X and Y each, so 40 slices in total. And then I need to do the same thing with another smoke sim, maybe bigger, so even more slices.

Thu, Dec 7, 10:31 AM · Rendering, Physics, Cycles, BF Blender

Wed, Dec 6

ronan ducluzeau (zeauro) added a comment to T53472: Cycles doesn't render smoke properly with adjusted clipping distances.

I think it is a known limitation that Camera Clipping is not working with smokes at rendering.

Wed, Dec 6, 4:19 PM · Rendering, Physics, Cycles, BF Blender
Felix (BlenderSpot) added a project to T53472: Cycles doesn't render smoke properly with adjusted clipping distances: Rendering.
Wed, Dec 6, 9:14 AM · Rendering, Physics, Cycles, BF Blender

Tue, Dec 5

Felix (BlenderSpot) created T53472: Cycles doesn't render smoke properly with adjusted clipping distances.
Tue, Dec 5, 11:21 AM · Rendering, Physics, Cycles, BF Blender

Fri, Dec 1

ronan ducluzeau (zeauro) triaged T53440: v2.79 - Particle System "Current Cache to Bake" Not Work as Confirmed priority.

Same on ubuntu 16.04 with 2.79 and master 1d33843

Fri, Dec 1, 2:25 PM · Physics, BF Blender

Fri, Nov 24

Bastien Montagne (mont29) raised the priority of T53159: OpenVDB cache doesn't support unicode characters in filename from Incomplete to Confirmed.

Did a quick check here on linux (which is utf-8 unicode system since… ages), with non-ascii chars in file name, and it works perfectly well.

Fri, Nov 24, 10:00 AM · Physics, Platform: Windows, BF Blender

Oct 31 2017

Sergey Sharybin (sergey) added a commit to T52533: Blender Shuts down when rendering duplicated smoke domain.: rC5238b1982e2b: Fix T52533: Blender shuts down when rendering duplicated smoke domain.
Oct 31 2017, 4:38 PM · Physics, Cycles, Rendering, BF Blender

Oct 23 2017

Peter (RockonWater) added a comment to T52791: Upon opening simple smoke simulation .blend file => Windows dialog: Blender has stoped working..

I just tested if it would work on my PC this blend (different hardware) also windows 10, it worked on both GPU gforce410M and CPU i7.

Oct 23 2017, 8:34 AM · Physics, BF Blender

Oct 16 2017

ronan ducluzeau (zeauro) added a project to T53083: Bake All Dynamics doesn't work when baking particle hair: Physics.
Oct 16 2017, 11:32 AM · Physics, BF Blender

Oct 15 2017

ronan ducluzeau (zeauro) triaged T53073: Force destroys particles rotation as Confirmed priority.

I can confirm that there is same problem on linux, too.

Oct 15 2017, 3:07 PM · Physics, BF Blender
Serge Lyatin (SergeL) created T53073: Force destroys particles rotation.
Oct 15 2017, 11:06 AM · Physics, BF Blender

Oct 10 2017

Kent Holt (kholt) added a comment to T52785: Blender2.79_animate_particles_crash.

Yes, close it. The problem seems to be related to the rate at which blender/other uses CPU SIMD memory. The assembler code is not easy to read into why values returned are causing an exception.

Oct 10 2017, 6:21 PM · Physics, BF Blender
Bastien Montagne (mont29) closed T52785: Blender2.79_animate_particles_crash as Archived.

OKI, closing then, since it seems it’s not related to Blender.

Oct 10 2017, 10:50 AM · Physics, BF Blender

Oct 2 2017

Kent Holt (kholt) added a comment to T52785: Blender2.79_animate_particles_crash.

With further research into the NT kernel library functions have seen that this is sometimes the case.
Blender does work with the objects and scene given. It is something in the low level OS that
caused the first few crashes. Thanks.

Oct 2 2017, 4:30 PM · Physics, BF Blender
Kent Holt (kholt) added a comment to T52785: Blender2.79_animate_particles_crash.

I've added a debug file that shows it is doing nothing very slowly. "blender_debug.txt"
Very slow at less than 1 fps.
I can lower the number of particles/hairs and does great.
The crashes started then stopped, and now animation is very slow. That crash data is in the original post.
Would be interested to see the differences in computer systems.

Oct 2 2017, 12:56 AM · Physics, BF Blender

Oct 1 2017

LazyDodo (LazyDodo) added a comment to T52785: Blender2.79_animate_particles_crash.

First animation play though is a little slow , but once cached it seems to play flawlessly at 18fps , what's steps are required to make it crash?

Oct 1 2017, 10:05 PM · Physics, BF Blender
Kent Holt (kholt) added a comment to T52785: Blender2.79_animate_particles_crash.

Oct 1 2017, 9:33 PM · Physics, BF Blender

Sep 29 2017

Kent Holt (kholt) added a comment to T52785: Blender2.79_animate_particles_crash.

Sep 29 2017, 7:54 PM · Physics, BF Blender

Sep 28 2017

LazyDodo (LazyDodo) assigned T52873: Vertex Weight Proximity breaks Rigid Body simulation to Sergey Sharybin (sergey).

Can confirm the behavior, unable to say if this expected behavior though. @Sergey Sharybin (sergey) ?

Sep 28 2017, 7:46 PM · Modifiers, Physics, BF Blender
LazyDodo (LazyDodo) closed T52238: Gravity ignores units scale as Archived.

Can confirm the behavior, however, it's working as designed, and even if we were to go out and change this behavior it's not and easy fix and it is likely that the physics will get some rework in 2.8 anyhow, so I'm gonna have to classify it as a feature request and close it, we'll revisit once the physics code in 2.8 gets some love.

Sep 28 2017, 7:43 PM · Physics, BF Blender
LazyDodo (LazyDodo) closed T52832: Segfault when playing baked particle + explode simulation as Archived.

I can't seem to be repro at all, given you solved the issue your self i'm gonna close the ticket, if you ever come up with a fool proof set of steps to trigger the issue we'd happily take a look at it though.

Sep 28 2017, 4:30 PM · Physics, BF Blender
LazyDodo (LazyDodo) triaged T52785: Blender2.79_animate_particles_crash as Incomplete priority.

Please attach a .blend exhibiting the issue.

Sep 28 2017, 4:16 PM · Physics, BF Blender

Sep 22 2017

Serge Lyatin (SergeL) added a comment to T52873: Vertex Weight Proximity breaks Rigid Body simulation.

Well it seems Vertex Weight Proximity is not the problem, another modifiers like Subsurf or Triangulation placed before second Displace also break simulation

Sep 22 2017, 1:57 PM · Modifiers, Physics, BF Blender
Serge Lyatin (SergeL) created T52873: Vertex Weight Proximity breaks Rigid Body simulation.
Sep 22 2017, 1:26 PM · Modifiers, Physics, BF Blender

Sep 21 2017

Bastien (Pik) added a comment to T52832: Segfault when playing baked particle + explode simulation.

Disabling the disk cache (after invalidating it) for all objects solves both problems.

Sep 21 2017, 1:57 PM · Physics, BF Blender

Sep 19 2017

Bastien (Pik) added a comment to T52832: Segfault when playing baked particle + explode simulation.

The result of my tests so far:

  • If I free all bakes and invalidate the cache, the simulation runs ok at first. Replaying it makes it crash.
  • Disabling the disk cache makes it crash.
  • If I free all bakes, invalidate the cache, and run the simulation again, it doesn't crash. I still have the bug where I can't see all particle systems though. Strangely enough, this time I see two of them, the active one and another that "jumps" between meshes. Here's a video.
Sep 19 2017, 5:14 PM · Physics, BF Blender
Bastien (Pik) created T52832: Segfault when playing baked particle + explode simulation.
Sep 19 2017, 5:02 PM · Physics, BF Blender

Sep 18 2017

Campbell Barton (campbellbarton) added a comment to T52794: When i play animation, move timeline, or Bake, my Blender crashes.

This is caused by dynamic paint doing its own object data updating (BKE_object_modifier_update_subframe) which runs at the same time as the scene_update_object_func task see:

Sep 18 2017, 8:39 AM · Physics, BF Blender
Muhammad Aamir (Aamir) added a comment to T52794: When i play animation, move timeline, or Bake, my Blender crashes.

I removed dynamic paint and and applied again now its working.
Thank you for your help.

Sep 18 2017, 8:33 AM · Physics, BF Blender
Joshua Leung (aligorith) added a project to T52785: Blender2.79_animate_particles_crash: Physics.
Sep 18 2017, 6:05 AM · Physics, BF Blender
Joshua Leung (aligorith) added a project to T52791: Upon opening simple smoke simulation .blend file => Windows dialog: Blender has stoped working.: Physics.
Sep 18 2017, 6:04 AM · Physics, BF Blender
Joshua Leung (aligorith) triaged T52794: When i play animation, move timeline, or Bake, my Blender crashes as Confirmed priority.

Confirmed. This crashes here.

Sep 18 2017, 6:03 AM · Physics, BF Blender

Sep 17 2017

Dennis Fassbaender (dafassi) closed T52768: Smoke with artifacts, stripes as Resolved.

Allrigt, i see! Very nice from you- thank you very much. I understand what was going wrong!

Sep 17 2017, 7:06 PM · Physics, BF Blender
ronan ducluzeau (zeauro) added a comment to T52768: Smoke with artifacts, stripes.

Sep 17 2017, 5:33 PM · Physics, BF Blender
Dennis Fassbaender (dafassi) added a comment to T52768: Smoke with artifacts, stripes.

Thank you for this information!

Sep 17 2017, 2:38 PM · Physics, BF Blender
ronan ducluzeau (zeauro) added a comment to T52768: Smoke with artifacts, stripes.

Stripes are not due to adaptive domain. Blockyness was due to adaptive domain .
Stripes are consequences of physics settings.

Sep 17 2017, 12:13 PM · Physics, BF Blender
Dennis Fassbaender (dafassi) added a comment to T52768: Smoke with artifacts, stripes.

Thank you for the quick answer.
Ive checked this with a new domain, applyed scale, disabled addaptive domain. The effect is still there.
See the screenshot:

Sep 17 2017, 4:35 AM · Physics, BF Blender

Sep 16 2017

ronan ducluzeau (zeauro) added a comment to T52768: Smoke with artifacts, stripes.

It is a side effect of using adaptive domain.
Disable it. Recenter and scale a little bit the domain. And blockyness in simulation should be gone.

Sep 16 2017, 8:27 PM · Physics, BF Blender
Dennis Fassbaender (dafassi) added a comment to T52768: Smoke with artifacts, stripes.

Ive made a test with the maximal resolution of 512 and highres 2 - of course artifacts become smaller and less visible - but they are still there. It looks like smoke would have friction/is sticky to the simulation´s grid cells.
https://www.youtube.com/watch?v=EInB32aKuNo

Sep 16 2017, 4:07 PM · Physics, BF Blender

Sep 15 2017

Dennis Fassbaender (dafassi) created T52768: Smoke with artifacts, stripes.
Sep 15 2017, 7:43 PM · Physics, BF Blender

Sep 6 2017

Sergey Sharybin (sergey) added a commit to T52533: Blender Shuts down when rendering duplicated smoke domain.: rC0ea653a16d29: Fix T52533: Blender shuts down when rendering duplicated smoke domain.
Sep 6 2017, 3:03 PM · Physics, Cycles, Rendering, BF Blender

Sep 5 2017

Sergej Reich (sergof) added a comment to T50765: Rigid body dynamics: Initially deactivated objects are not activated on collision, but on bounding box intersection.

This is not really a bug but more of a limitation.
I have a patch that does proper deactivation in the rigid body improvements branch, but it wasn't committed because it wasn't clear how deactivation should be handled in blender in general.
I might dust if off since this really can be preveived as a bug.

Sep 5 2017, 1:12 PM · Physics, BF Blender
Sergej Reich (sergof) added a comment to T51233: Deformation checkbox should be visible but isn't.

This is intentional behaviour. "Final" includes generative modifiers which don't just deform the mesh but generate a new one.
Now we could do shenanigans like rebuilding the collision shapes every frame, but that would be extremely slow and unstable.

Sep 5 2017, 1:06 PM · User Interface, Physics, BF Blender

Sep 4 2017

Sergey Sharybin (sergey) closed T52533: Blender Shuts down when rendering duplicated smoke domain. as Resolved by committing rB33249f698780: Fix T52533: Blender shuts down when rendering duplicated smoke domain.
Sep 4 2017, 1:15 PM · Physics, Cycles, Rendering, BF Blender

Aug 31 2017

Bastien Montagne (mont29) reassigned T51214: Dynamic Paint Works Only in Viewport Render from Bastien Montagne (mont29) to Sergey Sharybin (sergey).

Bah, am now getting a straight crash when trying to switch to Cycles viewport render…

Aug 31 2017, 4:43 PM · Physics, BF Blender

Aug 29 2017

Dalai Felinto (dfelinto) assigned T52533: Blender Shuts down when rendering duplicated smoke domain. to Sergey Sharybin (sergey).

And the bug was introduced on rB272412f9c0d26.

Aug 29 2017, 4:33 PM · Physics, Cycles, Rendering, BF Blender