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+--- Thread: Mesh and Fluid Problem (/thread-1555.html)
Mesh and Fluid Problem - sc00b - 12-12-2019
Good day, we have a problem when we pour liquid into a glass, if you move it, fluids pass through this glass. How to fix it?
RE: Mesh and Fluid Problem - josemendez - 12-12-2019
(12-12-2019, 11:32 AM)sc00b Wrote: Good day, we have a problem when we pour liquid into a glass, if you move it, fluids pass through this glass. How to fix it?
This is good ol' tunneling. If you move an object by changing its transform, you're essentially teleporting it from frame to frame, which causes particles that were inside the container to be outside the next frame.
Try adding a ObiKinematicVelocities component to the glass (and a kinematic rigidbody). This will calculate actual linear/angular velocities from the transform position deltas, allowing continuous collision detection to kick in and reduce tunneling. See the FaucetAndBucket sample scene for an example.
RE: Mesh and Fluid Problem - sc00b - 12-12-2019
(12-12-2019, 11:34 AM)josemendez Wrote: This is good ol' tunneling. If you move an object by changing its transform, you're essentially teleporting it from frame to frame, which causes particles that were inside the container to be outside the next frame.
Try adding a ObiKinematicVelocities component to the glass (and a kinematic rigidbody). This will calculate actual linear/angular velocities from the transform position deltas, allowing continuous collision detection to kick in and reduce tunneling. See the FaucetAndBucket sample scene for an example.
You take it and try it yourself) you have everything falling through the bowl on that scene too) make transparency to the material. And you will see that there is a problem.
RE: Mesh and Fluid Problem - josemendez - 12-12-2019
(12-12-2019, 01:57 PM)sc00b Wrote: You take it and try it yourself) you have everything falling through the bowl on that scene too) make transparency to the material. And you will see that there is a problem.
Hi,
No particles fall trough the bowl in that scene for us, and no other user has ever reported it. Also, transparency has nothing to do with physics, it only affects rendering.
See video:RE: Mesh and Fluid Problem - sc00b - 12-12-2019
(12-12-2019, 02:19 PM)josemendez Wrote: Hi,https://youtu.be/hz8KmORpuDM?t=21 - So you catch, you pour liquid through the bottom on the floor, make a transparent material and see.
No particles fall trough the bowl in that scene for us, and no other user has ever reported it. See video:
Transparency has nothing to do with physics, it only affects rendering.
RE: Mesh and Fluid Problem - josemendez - 12-12-2019
(12-12-2019, 02:22 PM)sc00b Wrote: https://youtu.be/hz8KmORpuDM?t=21 - So you catch, you pour liquid through the bottom on the floor, make a transparent material and see.
Hi
I'm not sure I understand. You mean changing the bucket material to a transparent one?
RE: Mesh and Fluid Problem - sc00b - 12-12-2019
(12-12-2019, 02:23 PM)josemendez Wrote: Hi
I'm not sure I understand. You mean changing the bucket material to a transparent one?
Yes
RE: Mesh and Fluid Problem - josemendez - 12-12-2019
(12-12-2019, 02:32 PM)sc00b Wrote: Yes
Hi,
I did that, but I fail to see any difference. I don't see how changing the rendering material of an object could alter its physical behavior, rendering and physics are entirely different systems. Here's the result:
RE: Mesh and Fluid Problem - sc00b - 12-12-2019
(12-12-2019, 02:42 PM)josemendez Wrote: Hi,And another question, where to set up the repulsion of the fluid from the fluid? And then we get jumping water)
I did that, but I fail to see any difference. I don't see how changing the rendering material of an object could alter its physical behavior, rendering and physics are entirely different systems. Here's the result:
RE: Mesh and Fluid Problem - josemendez - 13-12-2019
(12-12-2019, 08:20 PM)sc00b Wrote: And another question, where to set up the repulsion of the fluid from the fluid? And then we get jumping water)
Repulsion (pressure force) is not configurable, it is calculated to try and maintain a constant density. That's precisely what makes fluid "fluid". Artificially increasing pressure forces would make the fluid "explode", decreasing them would make it collapse.
You can increase the amount of substeps in the FixedUpdater, or the amount of density iterations in the ObiSolver to make the fluid less compressible. (increase simulation quality)
Here's a list of all configurable fluid parameters:
http://obi.virtualmethodstudio.com/tutorials/emittermaterials.html