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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

Yesterday

Philipp Oeser (lichtwerk) added projects to T67654: Particle Settings Title in Properties Panel Won't Update Until Mouse Over: Physics, User Interface.
Wed, Aug 21, 9:57 PM · User Interface, Physics, BF Blender
Philipp Oeser (lichtwerk) added a project to T67720: Smoke Cache deleted when hiding the smoke domain: Physics.
Wed, Aug 21, 9:41 PM · Physics, BF Blender
Philipp Oeser (lichtwerk) added a comment to T69000: Hair particle system refresh and crash problem .

This is the backtracke for deleting a whole particle, then Undo (cannot reproduce an Undo crash if I only delete a particle key...)
There, some ParticleCacheKey is broken...

Wed, Aug 21, 8:27 PM · Dependency Graph, Physics, BF Blender
Philipp Oeser (lichtwerk) added a comment to T69000: Hair particle system refresh and crash problem .

Blender, you keep confusing me.

Wed, Aug 21, 8:19 PM · Dependency Graph, Physics, BF Blender
Philipp Oeser (lichtwerk) added projects to T69000: Hair particle system refresh and crash problem : Physics, Dependency Graph.

Can confirm

Wed, Aug 21, 5:22 PM · Dependency Graph, Physics, BF Blender
Dalai Felinto (dfelinto) updated the task description for T66307: Nodes & Physics Module.
Wed, Aug 21, 3:44 PM · Physics, Nodes, BF Blender
Dalai Felinto (dfelinto) created T68981: New hair system.
Wed, Aug 21, 3:44 PM · Physics, BF Blender
Philipp Oeser (lichtwerk) added projects to T68979: Decouple physics and animation clock: Animation, Dependency Graph.
Wed, Aug 21, 3:40 PM · Dependency Graph, Animation, Physics, BF Blender
Philipp Oeser (lichtwerk) added a project to T68978: Depsgraph integration of physics: Dependency Graph.
Wed, Aug 21, 3:39 PM · Dependency Graph, Physics, BF Blender
Jacques Lucke (JacquesLucke) merged task T52238: Gravity ignores units scale into T61313: Physics ignores unit scale.
Wed, Aug 21, 3:35 PM · Physics, BF Blender
Bauke Conijn (bcmpinc) added a comment to T52238: Gravity ignores units scale.

Then it's still a UI bug. Because if the unit scale only affects the UI, then changing it should affect how the gravity is displayed in the UI.

Wed, Aug 21, 3:33 PM · Physics, BF Blender
Dalai Felinto (dfelinto) created T68980: Everything nodes.
Wed, Aug 21, 3:32 PM · Physics, Nodes, BF Blender
Dalai Felinto (dfelinto) created T68979: Decouple physics and animation clock.
Wed, Aug 21, 3:31 PM · Dependency Graph, Animation, Physics, BF Blender
Dalai Felinto (dfelinto) created T68978: Depsgraph integration of physics.
Wed, Aug 21, 3:30 PM · Dependency Graph, Physics, BF Blender
Philipp Oeser (lichtwerk) added projects to T68396: Unable to change any Collision input value after it has been keyframed: Physics, Animation, Dependency Graph.
Wed, Aug 21, 3:24 PM · Dependency Graph, Animation, Physics, BF Blender
Jacques Lucke (JacquesLucke) added a comment to T52238: Gravity ignores units scale.

As mentioned by @LazyDodo (LazyDodo), this is working as designed currently. The unit scale only affects the UI. We might change this at some point, but for now this is not a bug.

Wed, Aug 21, 3:24 PM · Physics, BF Blender
Philipp Oeser (lichtwerk) added a project to T68290: Baked particles dont render in final frame: Physics.
Wed, Aug 21, 2:10 PM · Physics, BF Blender
Philipp Oeser (lichtwerk) added projects to T68712: particle rotation phase breaks after keyframing.: Physics, Animation, Dependency Graph.
Wed, Aug 21, 2:01 PM · Dependency Graph, Animation, Physics, BF Blender

Tue, Aug 20

Dalai Felinto (dfelinto) updated the task description for T66307: Nodes & Physics Module.
Tue, Aug 20, 7:12 PM · Physics, Nodes, BF Blender
Garry R. Osgood (grosgood) added a comment to T68681: hair dynamics simulation doesn't work.

Thank you for the confirmation and the added information about edit mode effects. I think the object setting of flat/smooth shading is key - and that NVIDIA cards are in place. Those are the two salient aspects of this bug. People without an NVIDIA card cannot observe or confirm this bug.

Tue, Aug 20, 3:03 PM · Physics, BF Blender
Bastien Montagne (mont29) added a comment to T67335: particle system glitchy.

More than a week without reply or activity. Due to the policy of the tracker archiving for until required info/data are provided.

Tue, Aug 20, 11:15 AM · Physics, BF Blender

Mon, Aug 19

Jacques Lucke (JacquesLucke) updated the task description for T66307: Nodes & Physics Module.
Mon, Aug 19, 11:30 AM · Physics, Nodes, BF Blender

Sun, Aug 18

Yevgeny Makarov (jenkm) closed T51302: "Boid" Force field does nothing; should be removed as Resolved.
Sun, Aug 18, 3:18 PM · Documentation, Physics, BF Blender
Imre Varga (imrevarga) added a comment to T68681: hair dynamics simulation doesn't work.

Hi Garry,

Sun, Aug 18, 3:12 PM · Physics, BF Blender

Fri, Aug 16

Jacques Lucke (JacquesLucke) updated the task description for T66307: Nodes & Physics Module.
Fri, Aug 16, 5:22 PM · Physics, Nodes, BF Blender
Imre Varga (imrevarga) added a comment to T68681: hair dynamics simulation doesn't work.

Ok, thanks so far, I will go on trying on Sunday since I am travelling right now ...

Fri, Aug 16, 1:57 PM · Physics, BF Blender
Garry R. Osgood (grosgood) added a comment to T68681: hair dynamics simulation doesn't work.

Hi Imre,
At first glance, I see nothing unusual in system-info_imrevarga.txt. I need to spend further time with it, but not right now - I'm off to my job and won't be home again until quite late tonight - 22:00 zulu or so.
It seems that when you set mesh smoothing to flat, the simulation runs properly. (Here, linux/amd card, smooth/flat is irrelevant. The simulation runs correctly in both settings).
That suggests a workaround: First, set mesh smoothing to flat, then bake the simulation - in the cache settings, Particle properties, click on the "Bake" button and let the bake run for the full length of the animation. This is similar to what @Philipp Oeser (lichtwerk) proposed (Delete cache, set smooth off, Bake, test animation in the timeline - new step in bold). I propose that this approach will at least give you a sane cache of the simulation to save and work with and you can move forward with your project. If it does, I'd appreciate a confirmation here. Thanks!

Fri, Aug 16, 1:35 PM · Physics, BF Blender
Philipp Oeser (lichtwerk) added a comment to T68548: Mirrored Hair Particles has inverted normals for particle hairs.

OKi, lets close this then, its unlikely to be considered a bug atm...

Fri, Aug 16, 11:35 AM · Rendering, Physics, BF Blender
Hurşit (Xill) added a comment to T68548: Mirrored Hair Particles has inverted normals for particle hairs.

Thanks that solves my problem, i wasn't aware there was a work around like this.

Fri, Aug 16, 11:32 AM · Rendering, Physics, BF Blender
Imre Varga (imrevarga) added a comment to T68681: hair dynamics simulation doesn't work.

Thank you for your work so far,

Fri, Aug 16, 6:12 AM · Physics, BF Blender
Garry R. Osgood (grosgood) added a comment to T68681: hair dynamics simulation doesn't work.

@Imre Varga (imrevarga)
Similar to @Philipp Oeser (lichtwerk), I can confirm your observations up to, but excluding, your last step:

changing settings, clearing cash ... all to no avail

I do not have that issue here. Changing settings clears cache. Baking sucessfully caches a new simulation that shows none of the issues you report. Particulars:

  1. I temporarily cleared the Dynamic Hair checkbox, which cleared the cache loaded with your file.
  2. Then, probably unnecessarily, ran the animation with Dynamic Hair unchecked, just to satisfy myself that there were zero frames cached in memory.
  3. Finally, I restored the Dynamic Hair checkbox and baked all 100 frames. Blender reported a cache of 100 frames, consuming about 25.2 MB

This gave me a clean animation. See T68681.mkv Compare with the animation made with your original file and its original cached data. See T68681_original_cache.mkv
To make these animations, I modified your file slightly: I put a damped track constraint on the camera so that it would follow the head.

Fri, Aug 16, 2:44 AM · Physics, BF Blender

Thu, Aug 15

Stephen Swaney (stiv) closed T68691: Can't animate object after characterising it as smoke flow emitter as Resolved.
Thu, Aug 15, 8:09 PM · Physics, Animation, BF Blender
Paul (Magicmix) added a comment to T68691: Can't animate object after characterising it as smoke flow emitter.

Oh dear. Keyframes do work after all.

Thu, Aug 15, 8:02 PM · Physics, Animation, BF Blender
Paul (Magicmix) added a comment to T68691: Can't animate object after characterising it as smoke flow emitter.

Sorry - Blender info here: Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: rBf6cb5f54494e
Worked: (optional)

Thu, Aug 15, 7:59 PM · Physics, Animation, BF Blender
Paul (Magicmix) added a comment to T68691: Can't animate object after characterising it as smoke flow emitter.

Hi Philipp,

Thu, Aug 15, 7:58 PM · Physics, Animation, BF Blender
Philipp Oeser (lichtwerk) added projects to T68691: Can't animate object after characterising it as smoke flow emitter: Animation, Physics.

Cannot reproduce in a simple file [can animate, keys stay there, can change key values etc., all working fine]

Thu, Aug 15, 5:36 PM · Physics, Animation, BF Blender
Joselu (Xeluaxeman) added a comment to T68681: hair dynamics simulation doesn't work.

I installed previous nvidia driver but the bug persists in all windows 10 64bit Blender versions.

Thu, Aug 15, 2:50 PM · Physics, BF Blender
Joselu (Xeluaxeman) added a comment to T68681: hair dynamics simulation doesn't work.

Forgot to say that in linux ubuntu os did not find issues and seems to be more stable and faster with everything.

Thu, Aug 15, 12:40 PM · Physics, BF Blender
Joselu (Xeluaxeman) added a comment to T68681: hair dynamics simulation doesn't work.

I had similar unstable issues with windows 10 v1903 and gtx 1070.

Thu, Aug 15, 12:36 PM · Physics, BF Blender
Imre Varga (imrevarga) added a comment to T68681: hair dynamics simulation doesn't work.

I tried everything, bake, delete bake, bake again, go in and out of edit mode, change settings ... just doesn't work. There is a suspicion that it might be related to the RTX2070 or the latest driver of that since I also get the following issues:

Thu, Aug 15, 10:28 AM · Physics, BF Blender
Philipp Oeser (lichtwerk) added a comment to T68681: hair dynamics simulation doesn't work.

Cannot really reproduce, if I rebake (or change any setting -- which also clears the cache), everything is fine...

Thu, Aug 15, 9:38 AM · Physics, BF Blender
Philipp Oeser (lichtwerk) added a comment to T68681: hair dynamics simulation doesn't work.

T67958 might be related, will check

Thu, Aug 15, 9:33 AM · Physics, BF Blender
Philipp Oeser (lichtwerk) updated the task description for T68681: hair dynamics simulation doesn't work.
Thu, Aug 15, 9:33 AM · Physics, BF Blender

Wed, Aug 14

Philipp Oeser (lichtwerk) added projects to T68639: Modifier stack skin->subdiv->cloth corrupts the output mesh on simulation: Modifiers, Physics.

Confirmed, 2.79 has the same issues...

Wed, Aug 14, 5:20 PM · Physics, Modifiers, BF Blender
Philipp Oeser (lichtwerk) added projects to T65624: Python Write Access to Hair Particle Data Broken (2.8 vs. 2.79): Python, Physics.

@Olivier Maury (omaury): I assume this can be closed now? (from reading this, all issues seem to be resolved?)

Wed, Aug 14, 1:29 PM · Physics, Python, BF Blender
Philipp Oeser (lichtwerk) added projects to T68548: Mirrored Hair Particles has inverted normals for particle hairs: Physics, Rendering.
Wed, Aug 14, 1:02 PM · Rendering, Physics, BF Blender
Jacques Lucke (JacquesLucke) updated the task description for T66307: Nodes & Physics Module.
Wed, Aug 14, 11:20 AM · Physics, Nodes, BF Blender
Bauke Conijn (bcmpinc) added a comment to T52238: Gravity ignores units scale.

No, this is still an issue in 2.80.

Wed, Aug 14, 2:19 AM · Physics, BF Blender
dark999 (dark999) added a comment to T52238: Gravity ignores units scale.

@stewie mazen (stewie) you can check it youself, just dowbload Blender 2.80 Stable from here

Wed, Aug 14, 1:42 AM · Physics, BF Blender
Everton Schneider (eversimo) added a comment to T68627: Simulations do update animations on frame rate change.

In my tests here I just cleaned the cache and the new frame rate works as it should. What happens is if you cache rigidbody at 24fps and then change the frame rate to another value like 60fps the playback will use that cached frames at 24fps and playback that cache with the new 60fps, resulting in a faster playback only on that cached(at 24fps) section of the timeline. that's why you should clean your cache (just changing some physics values) when you change the frame rate of your project.
What could help here is if you change the fps value it could clean the cache for you... but I'm not sure if it "should" clean the cache...

Wed, Aug 14, 12:07 AM · Physics, BF Blender