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ekubik

animated flip fluid source

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Hi everyone,

 

I'm coming from using Maya and RealFlow for effects more predominantly but am trying to work in Houdini 13 right now, and could use some advice/guidance.

 

I have an animated dragon in Maya that I'm taking into Houdini for the end result basically having the dragon melting. I brought the animation into Houdini as an alembic cache, and in Houdini saved it out as a .bgeo sequence. I'd like to use the dragon geo as a source for a flip fluid, but am not sure how to get the animation onto each frame, and if .bgeo sequence will even be usable with this situation. Sorry if I'm missing something obvious, as I'm still getting adjusted to Houdini. Any advice to ultimately get to the end goal of animated dragon geo that i can manipulate in a fluid-like manor would be greatly appreciated.

 

Thanks guys!!

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Thanks for the tip! I've actually seen that one, and it's helpful but I believe it simply covers using a static object :/

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First of all you shouldn't write abc to bgeo, if you need substepping.  Otherwise use timeblend to get floating frame out of bgeo sequence.

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I havent had the chance to take a look at Pradeep's file, but you can always scatter points in the dragon.
then have a attribute growing (your melting mask) then use a time shift to go one frame back in time and compare the mask attribute so that you get only the points that just got activated.
then delete those points out and source the flip sim from those.
merge the result of that sim with the points of the dragon which did not get activated yet and mesh that.
 

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OK I think I'm getting some ideas here! My problem is that I'm still using Maya-brain when trying to figure this out, and I'm starting to conceptually understand what I need to do... but it's still tricky getting everything set up for me. I'm looking at the file now and trying some things out. And I get the idea with the melt mask, very interesting... only my biggest thing right now is still just dealing with the dragon animation being carried over to the next frame of the flip fluid sim.

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At it's simplest, you need a state attribute (0 - 1) that decides when to allow particles to partake in fluid simulation.

 

Any particles who's state attrib isn't 1 will just have their position and velocity overwritten by the animation values in a geometry vop after the flip solve.

 

flipanim.hip

Edited by ikarus
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OK yes... that's the idea I'm looking for.... translating the position and velocity after each solve if it isn't being affected by the simulation yet. Thank you! So if I want to modify the behavior of when the fluid is/isn't being affected... i would want to do that in the state test vex?

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If its just vex based modifications yeah that would be the place to do it.

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Hi ikarus,

I was working on your setup. i am trying to melt an animated character. your setup lets me melt the object in a box or wipe way. either BBX or BBY which looks like wiping from one side. Is there anyway i can define that from this position/location particles should melt. like at the start; only the face would melt then after few frames the arms would melt. you know if i can get some control to define that which part should melt. any locator or helper object which i can manually animated to define the position or something like that?

looking for your fast reply. 

thanks so much

junyd

 

 

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