PhysicsProject
ActivePublic

Properties

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

Acorn Bits (AcornBits) added a comment to T50887: fluid simulation: generate mesh bug.

It is happening for us all the time, in more than 10 frames out of 180 of a simulation (resolution 550, smoothing 1, remove air bubbles Yes, speed 0.8).

Sat, Jun 24, 9:58 PM · Physics, BF Blender

Yesterday

Sebastián Barschkis (sebbas) closed T51837: Mantaflow fluid crashes as "Resolved".

Okay, here is what happened:

  1. The "crash" occurred only in Debug build configuration.
  2. When reading particle velocities from disk, the number of particles from the file header were not considered. They were only set in the particle system (positions, flags) reading routine. It's apparently safer to read them twice.
Fri, Jun 23, 9:54 PM · Physics

Wed, Jun 21

lucas veber (lucky3) added a comment to T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option).

Here is the patch:
https://developer.blender.org/D2719

Wed, Jun 21, 9:30 PM · Physics, BF Blender
lucas veber (lucky3) claimed T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option).

Sorry it's my first bug fixing time, i'm not sur to do it right.
I have a patch for this, can I claim this task?

Wed, Jun 21, 8:50 PM · Physics, BF Blender
Sebastián Barschkis (sebbas) added a comment to T51837: Mantaflow fluid crashes.

Yeah, I'm on it. Just couldn't reproduce the "instant crash" on neither Linux nor OSX. So it's either really a Windows problem or a faulty build.

Wed, Jun 21, 3:27 PM · Physics
Bastien Montagne (mont29) triaged T51837: Mantaflow fluid crashes as "Normal" priority.

Ideally would be better to communicate directly with the branch's author in that kind of cases… Will let @Sebastián Barschkis (sebbas) decide now.

Wed, Jun 21, 12:36 PM · Physics
Bastien Montagne (mont29) removed a project from T51837: Mantaflow fluid crashes: BF Blender.
Wed, Jun 21, 12:35 PM · Physics

Mon, Jun 19

Bastien Montagne (mont29) closed T51774: Children particles hair interpolation not correct with textures or dp as "Resolved" by committing rB3190eaf10942: Fix T51774: Children particles hair interpolation not correct with textures or….
Mon, Jun 19, 12:05 AM · Physics, BF Blender

Sun, Jun 18

mic lack30 (miclack) assigned T51837: Mantaflow fluid crashes to Sebastián Barschkis (sebbas).
Sun, Jun 18, 11:53 AM · Physics
mic lack30 (miclack) created T51837: Mantaflow fluid crashes.
Sun, Jun 18, 11:53 AM · Physics
Felix (BlenderSpot) renamed T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option) from "Physics: Fluid simulation. An outflow mesh doesn't remove additional, fluid mesh (fluid particles) that hits it. " to "Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option)".
Sun, Jun 18, 5:44 AM · Physics, BF Blender

Sat, Jun 17

Brecht Van Lommel (brecht) closed T51826: Fluid contour in final render is different from viewport preview as "Invalid".

In the fluid domain settings, there's different Final Display and Viewport Display modes. If those match the result is the same.

Sat, Jun 17, 6:38 PM · Physics, Rendering, BF Blender

Fri, Jun 16

Bastien Montagne (mont29) triaged T51774: Children particles hair interpolation not correct with textures or dp as "Confirmed" priority.
Fri, Jun 16, 10:57 PM · Physics, BF Blender
Serge Lyatin (SergeL) created T51826: Fluid contour in final render is different from viewport preview.
Fri, Jun 16, 6:15 PM · Physics, Rendering, BF Blender

Tue, Jun 13

Howard Matthews (howiem) added a comment to T51302: "Boid" Force field does nothing; should be removed.

OK: I've finally found some time to write some better documentation for this, but it'd be useful to check if this is correct. It seems:

Tue, Jun 13, 9:08 AM · Physics, BF Blender

Sat, Jun 10

Felix (BlenderSpot) edited the description of T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option).
Sat, Jun 10, 8:58 PM · Physics, BF Blender

Fri, Jun 9

Felix (BlenderSpot) edited the description of T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option).
Fri, Jun 9, 6:42 PM · Physics, BF Blender
Felix (BlenderSpot) created T51759: Fluid simulation. An outflow mesh doesn't remove additional fluid mesh (Generated by Fluid Particles option).
Fri, Jun 9, 7:13 AM · Physics, BF Blender

Tue, Jun 6

Manu Marin (gyakoo) added a watcher for Physics: Manu Marin (gyakoo).
Tue, Jun 6, 4:35 PM
Luca Rood (LucaRood) closed T50896: Particles behave differently in rendered animation than in viewport as "Archived".

This is an odd behavior indeed. Might be a mesh evaluation order issue...
However particles are subject to an overhaul in 2.8, so we are limiting the work on the current system to only regressions.
Thanks for the report, but as this is not a regression, archiving it for now.

Tue, Jun 6, 11:55 AM · Physics, BF Blender

Mon, May 29

Bastien Montagne (mont29) closed T51390: Blender 2 .78c will freeze or force close when adding particles at random. as "Resolved" by committing rB06ca2c9d0320: Fix T51390: Blender 2.78c will freeze or force close when adding particles at….
Mon, May 29, 4:12 PM · Physics, BF Blender
Bastien Montagne (mont29) claimed T51390: Blender 2 .78c will freeze or force close when adding particles at random..

Confirmed, issue is in DM evaluation code actually, never clears the deformedOnly flag when evaluating a generative modifier!!!

Mon, May 29, 4:07 PM · Physics, BF Blender

May 22 2017

Bastien Montagne (mont29) merged task T51111: Using an added Cube in combination with Particles > Volume > Grid results in missing particles. into T51332: Startup cube does not match other cubes' geometry - need to udate startup file.
May 22 2017, 11:13 PM · Physics, BF Blender

May 15 2017

Aaron Carlisle (Blendify) closed T51297: Use A Higher Hair Segment Limit as "Resolved" by committing rB4621583612fa: Fix T51297: Use A Higher Hair Segment Limit.
May 15 2017, 8:30 PM · User Interface, Physics, BF Blender

May 14 2017

gimble (gimble) edited the description of T51111: Using an added Cube in combination with Particles > Volume > Grid results in missing particles..
May 14 2017, 5:33 PM · Physics, BF Blender
gimble (gimble) edited the description of T51111: Using an added Cube in combination with Particles > Volume > Grid results in missing particles..
May 14 2017, 5:31 PM · Physics, BF Blender

May 10 2017

Leon Cheung (leon_cheung) added a comment to T51297: Use A Higher Hair Segment Limit.

Very nice solution, Aaron! ❤

May 10 2017, 4:59 AM · User Interface, Physics, BF Blender
Aaron Carlisle (Blendify) raised the priority of T51297: Use A Higher Hair Segment Limit from "Normal" to "Confirmed".
May 10 2017, 4:53 AM · User Interface, Physics, BF Blender
Aaron Carlisle (Blendify) added a comment to T51297: Use A Higher Hair Segment Limit.

Here is a fix which uses a soft limit of 50 and a hard limit of 128:

May 10 2017, 4:53 AM · User Interface, Physics, BF Blender

May 5 2017

Dimitar Pouchnikov (dimitarsp) added a comment to T44248: Dupligroup instances of particles instancing groups do not render in Blender Internal, but show fine in Viewport and Cycles.

I have observed the same bug. I guess it sill hasn't been addressed?

May 5 2017, 4:26 PM · Rendering, Physics, BF Blender
Bogumił (BogumilZ) added a comment to T51147: Fluid simulation - inflow - export animated mesh bug.

All I want to achieve is to fluid inflow object emit fluid the same way on non animated mesh and animated mesh. I already tried the displacement and ocean modifier, looks good but I wanted drops dripping from running character. As soon as I tick option "export animated mesh" inflow emits enormous amounts of fluid. Is there a way to make deformed mesh emit fluid like non deformed (not animated)?

May 5 2017, 11:10 AM · Physics, BF Blender
Aaron Carlisle (Blendify) moved T51390: Blender 2 .78c will freeze or force close when adding particles at random. from Backlog to Particles on the Physics board.
May 5 2017, 12:16 AM · Physics, BF Blender
Aaron Carlisle (Blendify) assigned T51390: Blender 2 .78c will freeze or force close when adding particles at random. to Luca Rood (LucaRood).
May 5 2017, 12:16 AM · Physics, BF Blender

Apr 30 2017

Howard Matthews (howiem) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Thought: perhaps renaming it to Boid Goal/Avoid field would help.

Apr 30 2017, 12:25 PM · Physics, BF Blender
Howard Matthews (howiem) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Crikey, just had a quick play—thanks Ronan!—and this is a hugely valuable feature. As he says, it lets you animate between Goals rather than moving the Goals (which produces a different effect). The lack of docs is the killer—the fact the strength needs to be negative for Goal use means it's even more unlikely folks will just stumble across its functionality.

Apr 30 2017, 12:10 PM · Physics, BF Blender

Apr 28 2017

ronan ducluzeau (zeauro) added a comment to T51147: Fluid simulation - inflow - export animated mesh bug.

I mentioned fluid control only to give trajectories to drops coherent with character movements.

Apr 28 2017, 9:42 PM · Physics, BF Blender
Bogumił (BogumilZ) added a comment to T51147: Fluid simulation - inflow - export animated mesh bug.

So to make it working right I need to put into domain a FLUID object and make character mesh a FLUID CONTROL object? As far as I imagine - this way my character will not emit any drops (as my basic intention was). Am I right?

Apr 28 2017, 7:31 PM · Physics, BF Blender
Luca Rood (LucaRood) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Ok, this makes sense. So we actually have a horrible case of misnaming, lacking documentation, and terrible code design.
I can look for a better way to handle this in the code at some point (when I start working on particles), but for now, I think it is a matter of fixing the docs. (And maybe coming up with a better name, as the field does not introduce any kind of "boyd behavior", but rather influences existing boyds particles...)

Apr 28 2017, 5:46 PM · Physics, BF Blender
ronan ducluzeau (zeauro) added a comment to T51147: Fluid simulation - inflow - export animated mesh bug.

There is a misunderstanding, here.

Apr 28 2017, 11:48 AM · Physics, BF Blender
ronan ducluzeau (zeauro) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Boïds fields are a 2.4x feature.
It only works with a Goal or Avoid rule for Boïds particles and a strength that must be negative for Goal rule and positive for Avoïd rule.
https://youtu.be/Uvltf_oBd9E?t=1m33s

Apr 28 2017, 10:47 AM · Physics, BF Blender
Howard Matthews (howiem) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Might have some weird boid uses as seen here https://www.youtube.com/watch?v=kyrhDTmPUAc

Apr 28 2017, 9:09 AM · Physics, BF Blender
Aaron Carlisle (Blendify) added a comment to T51302: "Boid" Force field does nothing; should be removed.

@Peter Boos (PGTART) It is not that, but the feature has no code behind it and literally does nothing.

Apr 28 2017, 12:12 AM · Physics, BF Blender
Peter Boos (PGTART) added a comment to T51302: "Boid" Force field does nothing; should be removed.

Might have some weird boid uses as seen here https://www.youtube.com/watch?v=kyrhDTmPUAc
Its not that if you have not used some feature inside blender that you should remove it, instead learn it.
Things might not always have up to date documentation either, but still thats no reason to remove it.

Apr 28 2017, 12:05 AM · Physics, BF Blender

Apr 26 2017

Luca Rood (LucaRood) added a comment to T51302: "Boid" Force field does nothing; should be removed.

I didn't look at boids.c, but since the code in do_physical_effector does nothing, and pdDoEffectors has no special case handling for boid (no calls to boids.c stuff), I can only see this force field being a noop.

Apr 26 2017, 6:34 PM · Physics, BF Blender
Aaron Carlisle (Blendify) triaged T51302: "Boid" Force field does nothing; should be removed as "Normal" priority.

I looked into this and I found this in the code:

case PFIELD_BOID:
	/* Boid field is handled completely in boids code. */
	return;
Apr 26 2017, 6:37 AM · Physics, BF Blender

Apr 24 2017

Leon Cheung (leon_cheung) added a comment to T51297: Use A Higher Hair Segment Limit.

+1 for soft limit.

Apr 24 2017, 3:17 PM · User Interface, Physics, BF Blender
Luca Rood (LucaRood) added a comment to T51297: Use A Higher Hair Segment Limit.

I really don't think this is the way to go about this. There is no point in slightly increasing the limit, as you can just as well find the new limit to be too low at some point in the future. I would be for keeping the 50 limit, but replacing it with a soft limit, that way, new users don't accidentally freeze their sims, but you are free to increase the the segments to whatever you want.

Apr 24 2017, 12:32 AM · User Interface, Physics, BF Blender

Apr 23 2017

Aaron Carlisle (Blendify) added projects to T51297: Use A Higher Hair Segment Limit: Physics, User Interface.
Apr 23 2017, 8:08 PM · User Interface, Physics, BF Blender

Apr 20 2017

Luca Rood (LucaRood) closed T45350: Cloth Simulator: "Free all bakes" doesn't clear bake, but "Free Bake" works as "Resolved" by committing rBee3faddfaaa1: Fix T45350: Cache not being recomputed with "Bake All Dynamics".
Apr 20 2017, 3:04 PM · Physics, BF Blender

Apr 19 2017

Germano Cavalcante (mano-wii) added a comment to T47195: Cloth penetration when the size of the faces in the cloth and collision object are different.

I have completely removed Bullet's plNearestPoints from the new cloth collision system in the cloth-improvements branch. I have instead implemented a brand new and more reliable function, tailored specifically for the new collision response system.

As a result, this issue (and many other collision issues) has been resolved in the branch, and will go either into 2.79 or 2.8.

Apr 19 2017, 5:48 PM · Physics, BF Blender