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rurik

Texture on Flip

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Hello

I have an imported OBJ file that has embedded UV's.

I'm transforming the object into a flip simulation so that it slowly melts over time.

I would like to have a texture map to the flip simulation as it maps to the existing geometry.

 

I'm trying to transfer the UV's from the imported OBJ to the Flip simulation by using an Attribute transfer that grabs the UV's from the vertices in the object, promotes them to points, and finally transfers them to the imported DOP geo.  However this solution doesn't seem to work, as the texture is seeminingly being mapped to each particle, instead of to the simulation as a whole (hope this makes sense).

 

Is there a better way to do this?  Using an attributefrommap SOP maybe?

 

Thanks

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If I am understanding you right, establish uv's on the points that go into the flip sim before the simulation.  Or, use a solver sop in dops to grab the flip points at their emission frame and transfer uv's there.  They should then be attached to the sim and move with the points.  I don't think transferring after the sim will work at all.

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Thanks Adam

 

The Obj I'm importing comes in with a set of UV's.  They come in as Vertex attributes, so I'm promoting them as Point attributes.

Then I put a Rest SOP at the end of my SOP tree, and then object merge that into the "my_geo_fluid" op, where all the surfacing is happening.  

I use the Object Merge to read in the color values, and then apply them to the "fluid geometry".  So far so good, which tells me the UV's are actually being read...However what I think is not being read is the Rest position...

So I'm confused as to where it needs to be set...

See the screenshots of my current setup attached.  I wonder if at a glance it is easy to see what I'm doing wrong.

 

Geo_SOP.JPGFluid_SOP.JPG

Thanks for your help!

Alex

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Check out the attached file.  I am not sure what you are trying to do with rest position.  I don't think that has much to do with uv's, just tracks initial position throughout the sim, which is useful for driving procedural noise and other procedural textures, but I don't think is useful for uv's.  You really need to track uv coordinates through the sim.

 

Anyway, the first file I am including is very simple.  A sop solver attribute transfers uv coordinates from the source geometry at frame 1.  After building the fluid mesh, the uv's are transferred to it from the sim points.   Only thing weird I did was turn off reseeding in the flip solver, just to keep a constant point count.

 

The second file is even easier, just changes the way particles are sourced into the sim.  This way, no sop solver is needed and the flip particles just inherit the uv's from the source.

 

Hope these help!

-Adam

FluidWithUVs.hipnc

FluidWithUVs_V02.hipnc

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Thanks for sending these...The second one makes a lot of sense, but I think your setup is different than what the shelf is giving me, which is maybe part of my problem.

 

I can see in your sphere object, that you are going through a pointsfromVolume SOP and then doing your attribtransfer there, which makes sense...

 

When I use the shelf tool ("FlipFluidFromObject") I get a very different setup.  I'll try to roll my own SOP>DOP>SOP chain and see if I can re-create what you did, which is exactly what I'm after...

 

Thanks for taking the time to make these example files!

Alex

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Are you using H13?  I assume you used the shelf, since you have an "autodop" and not just a dopnet?

It looks like unless I do things manually I can't quite get your setup..If you are using H13, which shelf tool did you use?

 

Thanks again

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I am using H13.  For the first file, I started with the shelf tools and then re-wired and modified the DOP network (multisolver/sop solver setup).  The second file, I just modified the first file, creating most of the nodes from scratch.  So, autodop network in that file is just a leftover remnant from the first file.  It is not properly wired up, for example, linking particle separation parameters in the points from volume and flipobject, etc, but that is only a few extra minutes to do. If you like that setup and want to make a shelf tool for yourself, it should be easy enough, if you know some basic python.  A lot can just be copy-pasted from the standard flip shelf tool.

 

-Adam

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On 4/24/2014 at 6:59 AM, bandini said:

Check out the attached file.  I am not sure what you are trying to do with rest position.  I don't think that has much to do with uv's, just tracks initial position throughout the sim, which is useful for driving procedural noise and other procedural textures, but I don't think is useful for uv's.  You really need to track uv coordinates through the sim.

 

Anyway, the first file I am including is very simple.  A sop solver attribute transfers uv coordinates from the source geometry at frame 1.  After building the fluid mesh, the uv's are transferred to it from the sim points.   Only thing weird I did was turn off reseeding in the flip solver, just to keep a constant point count.

 

The second file is even easier, just changes the way particles are sourced into the sim.  This way, no sop solver is needed and the flip particles just inherit the uv's from the source.

 

Hope these help!

-Adam

FluidWithUVs.hipnc

FluidWithUVs_V02.hipnc

I couldn't make 2nd file to work with H17.5. I assume it has something to do with how to connect the source to a FLIP solver. This has changed with the new version. If someone knows how to convert it to the new version of Houdini I would be happy to see it as well.

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