Jump to content


  • Content count

  • Donations

    0.00 CAD 
  • Joined

  • Last visited

  • Days Won


Everything posted by ejr32123

  1. pyro smoke trail

    kinda hard to trouble shoot without a file, but can you try using a volume visualization node and set density to flame/temperature (depending on which you are using for fire). You can then visualize the flame/temp field in the viewport. Is it still disappearing/reappearing? edit: did you cache your pyro simulation? it is possible you dragged the playhead to an uncached area so its rendering incorrectly.
  2. Track pyro simulation to a moving (Alembic) object

    not really sure what you mean but if you use sparse pyro it will automatically resize the container to keep in all the areas with density/flame.
  3. shock wave

    here is a start shock.hiplc
  4. Exporting Pyro Simulation as VDB problem

    when it says out of memory its talking about ram I believe. Try doing the same process but opening up task manager and see if the ram goes to 100% How much ram does your machine have?
  5. Pyro bake volume node isnt working

    Its because you are not sourcing any temperature or burn. If you go to volume rasterize attributes and only use temperature and burn it will be empty. You need to change the coverage attribute to either nothing or change the way you are sourcing (like giving each particle a density value higher then 0). You have density as your coverage attribute and your points that have burn/temperature have a density value of 0. So you are effectively multiplying your burn/temperature by 0. So only density is being sourced.
  6. dealing with open geometry

    sorry, I cannot. But using the different methods listed above pretty much have me covered
  7. dealing with open geometry

    Hello, For some recent freelance work I have received geometry from modeling which will interact as a collider for some smoke simulations. The geometry (as often is the case it seems) isn't properly closed up in areas that are not rendered. I assume modeling thinks if something isn't being rendered the topology isn't important. It's difficult to set up sdf collisions for pyro because everything is open. Any advice for how to deal with this? Is there some alternative to pyro collisions that do not require sdf's, or do I just need to close everything up. I feel like I would spend more time fixing the geometry then doing the simulation : ) Thanks
  8. dealing with open geometry

    Thanks all for the answers
  9. Sparse Pyro Combustion Emission

    the flame range doesn't actually seem to work for me. Smoke is always emitted everywhere even from the very start.
  10. dealing with open geometry

    Unfortunately that doesn't work. The collision is way too thin. I did something similar. I use a vdb from polygons then reshape sdf on dilate to make it thicker
  11. dealing with open geometry

    oh nice, I will try that
  12. dealing with open geometry

    1000 iq move, lol. I will give that a shot
  13. dealing with open geometry

    haha, unfortunately that doesn't work in this case
  14. texture bake seams

    found the problem in an older forum post. In the bake rop driver settings, the the alpha channel is being copied to the extracted image planes. You can just leave that empty and your texture will work.
  15. texture bake seams

    Hello, I used to have no trouble baking textures, but no matter what I do I always have seams. I am not sure which version this started happening. If I use the lab bake texture node (which seems to be using an older version of the texture bake rop) it works perfectly fine. Look at my viewport render. the left side is using the texture bake rop and the right side is using the labs texture bake (as I said, I think its using an earlier version of the bake rop node). I practically mirrored bake texture rop settings to the labs bake texture, but its still not working. Any thoughts? edit: you can see the export from the regular bake has an alpha channel for some reason so you dont see the diffuse fill. bake_test.zip
  16. Is there a way(particles)

    you mean like this? hip included pop_curve.hiplc
  17. pyro look problems

    Hello: I am seem to be having trouble getting pyro to look the way I want it too, especially with stylized fire/smaller flames. (For me at least) the worst looking part of any sim I do is either the sourcing or smoke close to the source. It seems like interesting detail doesn't really happen in smoke until disturbance/turbulence hits later on in the sim's life. If you look at this fire sim I rendered, https://vimeo.com/440159408 it looks fine, but if I want the flames to be smaller it looks pretty bad (no detail or nice motion). See where my blue line is on the photo, if I add dissipation or change the flame lifespan to end around the blue arrow, the fire looks pretty bad and you don't get too see nice swirls/licks as you can once it reaches the pink-ish arrow. The TLDR is I can get nice looking sims at bigger scales, but when I need smaller flames/smoke its hard to get nice motion early on in the sim. Any tips?
  18. I do not have much experience with hair other than using xgen for a bit and watching tutorials/demos of other software like ornatrix. I recently spent a lot of time learning hair in houdini and I was wondering if other people had a similar experience. Sops vs OBJ. I hate working at obj level with hair nodes (or in general). You have to keep diving back and forth to different objects to access data, and it's really frustrating and painfully slow. So I switched to mainly using sops. However, things were really strange there too. The first thing I noticed is that none of the radial menus work. Since you can’t really freeze hair (so they won’t be affected by the brush) you can select hair then use the radial menu to get back to the brush and only brush those selected hairs. However, that doesn’t work in sops because the radial menu and most of the shelf tools only seem to work at obj level. To brush only selected hairs, you have to click the guide groom node, click the selection arrow, select the hairs you want, then hit enter, then manually switch to the brush tool. That is just way too slow. Then, if you change the amount of hairs, your selection breaks and the hair does weird things. Changing the amount of hair going into a brush node generally works fine because it interpolates, unless you made selections in the process (which is what I have been doing). Some things just don’t make sense or are slow. The tools were clearly designed to work at obj level, even though you can access them in sops. 1. Manually placing guides at sop level. I turn on shade open curves so I can see the hair width when working at sop level. When you use the guide brush tool to place guides, the guides immediately disappear. I found out that working in sops, the guide groom plant guide tool does not allow you to create a width attribute. This means the width gets assigned a value of 0 and thus disappears because you need a width attribute. The way I fix it is to unlock the digital asset and manually add the attribute. See video 2. Changing the length of the hair does not resample the width along length. This literally makes 0 sense. If I use the guide brush to lengthen tapered hair, it seems to not really get longer. However, when I rendered it my hair was much longer than the viewport. Then I learned that it's because width was not resampled to match the new length, so 60% of the hair was invisible in the viewport. To fix it, I add a resample to add a curveu attribute, then I resample the width along curveu. See video 3. Some brushes are insanely slow. The smooth brush is the slowest of them all, you can only brush a few hairs before it gets too slow to use. 4. The brushes in general just don’t seem to work well compared to other software I have seen. They are generally slower and harder to use/give you worse results. 5. The clumping can give you different results based on your uvs, and if you update the uvs the clump node doesn’t always update correctly. I have to delete the clump node then hit undo to get it to update, or restart houdini. 6. Recaching. This is so annoying. If you work in sops, the recache menu button doesn’t work so you have to manually select all the guide grooms and hit recache. I also noticed in sops that I have to do this when I load my project, otherwise I get shown incorrect results. When working at obj this was not an issue. I don’t want this to be all negative so I will say this: The parts that are procedural, the guide process nodes are amazing. The guide advect tool is amazing too. You can get very good results without ever touching a brush-this is the great part. Does anyone else have any thoughts on how grooming compares to other softwares? To reiterate, I just found manual grooming with brushes to be really slow and painful, with a lot of manual setup or switching between obj nodes.
  19. kinefx retargeting cleanup

    seemed to fix it by adding a fbik configure joints and limiting rotation to x axis
  20. edit: I figured out how to lock the foot, I used two different stabilize joints: one to keep the the foot from slipping, and one to match the rotation on the foot to the floor. I did that inside to an ik chain to update the rest of the leg hip is below on next post. Hello, A few questions about cleaning up a mocap clip from mixamo when applied to this mech character. I could not include the whole mech, but the l eg is included in the hip. If you play the clip, you see unrealistic motion because I need all the joints under the left upper leg joint to stay in the same position in x. You can see how it bends my mechanical leg outward to the left, which is no good. Basically, what ever x axis position the upper left leg joint is at, everything below it must be at the same x position. The bottom rig is the rest pose, whats circled is the way it should look. All the joints in the same x position. odforce.zip Final question is how to keep the foot resting on the ground. Is that joint stabilize? I just want the foot to lay flat while its on the ground. Thanks!
  21. kinefx retargeting cleanup

    update: I figured out the 2nd part, how to orient the rotation. As I said earlier, I used two stabilize joints, one to stop sliding, and one to fix the orientation. All that going into an ik solver. hip file included (its not prefect, but you get the idea). I still need help with the first part though. odforce.zip
  22. tube groom in houdini

    Hello, In (xgen) maya you can select tubes and create guide curves based off the initial tubes selected, given that your tubes are open and have uvs with the 0 toward the root (next to scalp). How can I recreate this setup in houdini? I found this tutorial here https://youtu.be/CqdMxq4N-uo but that method only seems to work (the part where he generates the beard from tubes) if you create the tubes in houdini, because his method uses uv's that were generated from the curves that the tubes are from, so the uv's are perfectly laid out for the tube spanning 0-1 in a square. My tubes are from the modeler and are messy and have no uvs. Any ideas on how xgen does it under the hood or any other way in houdini? Thanks
  23. Using houdini for hair in a maya pipeline

    ill look at bifrost
  24. Hey, Was wondering if anyone could offer any insight on using houdini to generate/simulate hair in a maya pipeline. One method I could use xgen to generate the hair and sim the guides in houdini then bring that back into maya. But then......I would have to use maya and xgen, which I really don't like. Since we are using redshift I know I could export the hair as a RS and bring it into maya. But then if we want to change the hair width, make it slightly longer, etc the other maya artists would not have that control it would require me to change the settings in houdini and export. Can anyone offer some knowledge on a work flow creating hair in houdini and bringing it into maya? Also side note, importing curve abc files from houdini into maya seems really inefficient. The way it imports into maya is quite strange, like a new shape for each curve or something weird like that. Thanks
  25. Hello, I am trying to use the flipbook motion vector with an explosion exported from houdini using sidefx labs tools. I followed a couple tutorials and I am pretty sure I got the motion vector intensity setting right and everything else. But for some reason it is stuttering really badly. My explosion (in real time) is pretty fast moving. Maybe its moving too fast and it is only 24 frames a second? If you notice, toward the end of the flipbook, it starts to stop stuttering when the explosion is moving slower at the end. That's why I was wondering if its maybe I just need a slower explosion or just a higher frame rate atlas, like 60 instead of 24. Has anyone gotten the sidefx labs motion vectors to work? Any thoughts?