sebkaine

Thanks for the tips Andrii ! and sorry for the delay answer. I will try to do that in full dops, see how it goes, and post back the result if they are good enough ! Cheers E

Hi Paul, This might be interesting https://www.gerbertgosch.com/rndtextureflowpt1 Basically the default workflow in H is base on the combo - rest pose activation in the fluid solver. - rest pose reading in the shader with the rest pose solver The problem is that restsolver is mantra based, i think UE give you 4 uv channel so their might be a way to store rest in uv3/uv4 and interpret them in UE. you can access the code of mantra dualrest solver in the asset. Then you can try to reproduce that logic in the material editor of unreal. Not an easy task to get proper UV on fluid, yo will have to do your homework.

well i would like to find a way to create a proper rest pose to be able to post-process the grids in dops then post-process the grids in shops directly. basically the goal is always the same get the extra detail without having to pay the full price of it at sim time. i agree with you that now computer are really faster and a brute force approach might now be the best things in 2019 ? But actually to do upres things in H you basically have by default : - rest / rest 2 + restsolver -> which is not a convincing method imo for reason describe previously - upres -> which can be an efficient / convincing way but is also very tedious , setup the proper noise, second solve , lot of disk cache needeed to save the grid. I think it would be possible to replace those 2 methods, (uprez + displace), with a proper rest pose. Actually many great pyro guys who i ask the question, use the gradient stuff describe by andrii, i was just curious to know if some have other approach. The point base technics describe by Mainroad always put my interest cursor to the max, maybe because i still find that their pyro are the best i have ever seen in H.

Yes sorry for my bad english it's more a pulsing effect, but at the end it's not so good. it works for fast whispy smoke, but you could get the exact same idea with displace and gradient. So that's why i would classify rest/rest2 tricks to the bad tricks , that can sometime save you. but it remain an awkward method imo. For Pop , you just nail it . while it sound easy at first to advect some points on pyro to store some att. The hard part start when you whant - a coherent point cloud with always a correct distance beetween each point to get a proper sampling - how to reseed and manage the point when density disapear or when some area with high divergence in the previous frame , have very few point to store the data on the current frame Coherent space beetween each point + reseeding -> that start to sound like a FLIP things ? This concept of blending MAC grid / particles velocities to compute high detail with point is not new , on this 9 years old article , they already talk about that : Wrenninge-CapturingThinFeaturesInSmokeSimulations.pdf

Hi Bunker ! Thanks for your answer. You mean that it would be better to generate the restP i input in the noise function, not only base on the gradient but by combining the output of the dual rest solver and the gradient ? What type of operation do you have in mind to combine the two ? Add / Mix / Mult .... ? Are you sure that it will kill that nasty sliding effect that inherently come with dual rest ? I haven't done fluid for a long time, my skill on the subject are quite rusty. But i always find that dual rest was a bad idea to create a restP, because it force you to store 2 more fields and thus add some heaviness / slowness in the process. I also think that it work with interpolation and my guts tell me that it is either a bad idea / nor the most elegant idea to create implicit UV on a pyro. Andrii advise to use gradient for this, and it's not the first to tell me about this. While it look to work , i think it's more a way to have something that follow your simulation without sliding effects. But the gradient in itself is imo not a way to generate implicit UV. It's a trick that do work to apply noise without sliding. I feel that the most elegant way , was the mainroadpost way https://www.sidefx.com/community/main-road-post-stalingrad/ Because i have always love to mix pop and fluids, pops are light / fast / very easy to controll / fast to transfer info / light to store. It's also what i use a lot to inject stuff in the grid like density / temp / div etc ... It's also useful for tricks like vorticles. Switching from a fluid grid to particles is exactly what FLIP do. In my mind the best way would be to use the invert process for pyro , you work with a grid but you process each time a point cloud were you can operate things like uv computation and transfer that to the grid. But it's all theory and in practice i never succeed with the POP way ... ( sorry for long / wordy post ) Cheers E

thanks again for your hardwork guys ! MOPS is a beautiful project !

would it be possible to neutralize the transform of your char , in order to stick it at the center of the world , then work on a static char by using forces for wind, you could also take a certain percentage of the animation like 10% or 20%, to inject this in your sims for better result. then you reset to the correct transform with the baked anim of your cloth, and see if the tricks works ?

Well i have try to apply your method directly in shop by displacing directly the grid in mantra, i wasn't expecting much, but i must said i find that it work better than expected. The noise doesn't slide, i just have some unatural pattern that appears, but it's definitly interesting. I still can't figure why the grad can be used as restP , it's kinda counter intuitive imo, you might expect to use grad as a vector to push along the normal, not as a restP ... Here is a comparison with no mantra displace vs mantra displace. gradL05.hiplc gradL05.mp4

Ok i have made a stupid mistake , i load restP as a float not a vector, it looks to works on static field. Now i will have to try your tricks on a moving grid. gradL02.hiplc EDIT : well i have try on a moving grid , it's not bad, it does follow the fluid without sliding effects, but i get some artefact when i try to push things too much, i need to investigate more with this. But sound like a good tricks. gradL03.hiplc

Hi thanks for your answer Andrii, It looks very interesting. I don't see exactly how you interpret the grad value for displacement ? you normalize the grad , then input it in @P for noise computation ? but how do you combine it in the shader ? Thanks again for your time ! Cheers E grad.hiplc

Hi Guys, I haven't done any fluid sims in H for a while, and was wondering if i haven't miss any new fancy method to generate, implicit UV on a Pyro Object. The goal is to get a correct P position to displace the volume at rendertime in order to mimic exactly what Igor Kharitonov has done with FLIP object in these 2 scenario : https://www.gerbertgosch.com/rndtextureflowpt1 https://www.gerbertgosch.com/rndtextureflowpt2 Basically replicate this exact workflow but with Pyro Solver would be cool. Of course the goal is to stay away from dual rest pose. At the time i have try to replicate this with a POP sims advected in the Pyro that transmit P to a P rest field , but i never get a 100% good enough solution. I would be curious to know your pov and suggestion on wich direction , methods , technics , article that might help to find a proper answer to this problem. Thanks for your Lights ! Cheers E

- Better svg / font / text tools - Better UI for basic deformer Twist / Bend / Wire ... - listing and preview of shaders from external renderers in the material palette - glsl context were we can control all the viewport shaders with a nodal network like ShaderFx - Ability to work with a glsl PBR shader in the viewport without being forced to use a mantra shader - ability to export the glsl PBR shader to UE or Unity - new UI paradigm for task requiring manual interactivity with the viewport like modeling / sculpting / uv layout - COPS on steroid + UI enhancement of all CC tools Hue Curves / Curves / Histo - Faster Mantra / Faster Bake

@cinnamonMetal, well i do but not in digital format, it's on printed version of cinefex and computer graphic world magazine. You have and ipad app that sell old cinefex issue for only 5 bucks, lot of nice Maya and XSI ads there, sesi ad were kinda minimalist at the time. Maya best ad period were beetween 1999 and 2005 ... before the arrival of the dark ages. I will send you a PM with some few i have find online. and i will stop talking about Maya on a Houdini nerds forum, i think it will be a clever idea if i want to avoid any stoning scenario ...

I like their new old school advertising It remind me Alias / Wavefront prints for Maya 1.0 -> Maya 4.0

Looks great jordi. As a side note, you might already know but you can plug this directly in houdini https://github.com/wjakob/instant-meshes By using the Gamedev tools instant meshes https://www.sidefx.com/tutorials/houdini-game-dev-tools-instant-meshes-bridge/