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Everything posted by DonRomano

  1. Volcano wip

    Yeah I understand what you mean ! I'll try to change the shape, and scale down the trees so the volcano will have a more realistic scale ! Thank you !
  2. Volcano wip

    Heyy guys, Here's a wip of a volcano with Redshift. I've made the trees with a custom generator in houdini, the terrain is made with heighfields, and textures/leaves/grass is quixel. Next step is the simulations (this is not the final lighting, and of course not the final background ) Feedback is welcome Cheeers,
  3. Volcano wip

    So, to update, just added some smoke ! Tell me what you think of it ! Next step is to create some clouds and work on lighting ! Cheeers,
  4. Straighten Curve Segments?

    Maybe you can try with 2 resamples sop. Use one to straighten your curve, and then another one to add points back to your straightened curve.
  5. Create a group sop with bouding object, connect your object to the second input, and then delete the group ?
  6. Thin Sheet Fluid

    Hey everyone, so after my very long thread (https://forums.odforce.net/topic/44053-implement-kernel-maths-in-vex/) I finally found a solution. The setup works great at 0.05 res, you might have to dive inside the solver and change some parameters to get it work at other resolutions (especially to get the droplets). Here are some test : Emission threshold at 60 (depending on the situation, there might be some abusive expansion, like at the end on the rubber toy, but this seems impossible to fix when you want a full thin sheet) Stretch threshold at 0.75 / Surface Tension 0.5 Emission threshold at 15 / Stretch threshold at 1.25 / Surface Tension 1 Houdini default Flip with Surface Tension at 1 Crown test with 50 Emission threshold (problem with infinite expansion with liquid dropping from the collider) If someone has suggestion to improve it, feel free to tell me I'm still working on fixing the infinite expansion issue, but the emission threshold is doing great until 20-30 depending on the situation Cheers, thin_sheet_solver.hipnc
  7. Flip sim goes crazy when I add collision

    Try to change the division method to "division size" and put 0.005, and link it to the volume division in the collision source sop
  8. Flip sim goes crazy when I add collision

    Are you using drag in your simulation ? If yes, delete it and use a Geometry wrangle with (connected to the particle motion input) : v@v *= ch("drag_threshold"); And how many substeps do you have ? Try 3-3 it may solve your issue. Cheers,
  9. Hello guys, I try to implement the thin sheet feature (from this paper : http://www.cs.kent.edu/~zwang/schedule/zy11.pdf) but I'm stuck on this : How can I implement this, or translate this into vex ? I'm not sure if it's working with the grids and I should try to code it in a volume wrangle but I really don't know how I have to implement it. I tried this in a point wrangle (in a sop solver) : int pts[]; float kernel_result[]; pts = pcfind(0, "P", @P, ch("search_radius"), chi("search_count")); for(int i = 1; i < len(pts); i++){ vector pos1 = point(0, "P", pts[0]); vector pos2 = point(0, "P", pts[i]); float radius_mult = ch("radius_multiplier"); float radius = @pscale * radius_mult; float sum = (1 - pow(length(pos2 - pos1), 2) / pow(radius, 2)); if(0 <= length(sum) <= radius){ float result = sum; } else{ float result = 0; } append(kernel_result, result); } I'm sure it's not good and it's why I'm asking help ! If anyone here can help it would be much appreciated !! Cheers,
  10. Implement Kernel (maths) in Vex

    Interesting ! The expansion process is happening because the solver adds particles where there's a space (the min insert threshold) so wherever there's a space the solver fills it. Then, I managed to get droplets by adding a refining node that detects tendrils (using pc find and a threshold on neighbours count, as the tendrils points don't have much neighbours) and all the particles around there get snapped to form a droplet. But this technique works only with 0.05 res and it doesn't fix the infinite expansion issue. For sure the dissolve artifact is coming from the surface tension. I'm still working hard on it to find a solution but for now I'm stuck and I don't really know where to go... Cheers
  11. Implement Kernel (maths) in Vex

    Not yet.. I'm working on it !
  12. viscosity problem

    Maybe enable smooth in the particle fluid surface node and play with it ? Or you can create your own meshing system and use vdb smooth sdf , and also play with the adaptivity threshold ! Cheers,
  13. Implement Kernel (maths) in Vex

    Thanks Noobini !! So here's just a new test after some new vex trials : I'm pretty happy with the result but it only works at the resolution 0.05, and with the minimum insertion threshold set at 0.25... And I didn't manage to fix the infinite expansion of the fluid (as you can see below, he seems to be taking a shower with water coming from nowhere...) Still have a lot of work... Cheeeers, thin_sheet_test.hipnc
  14. Implement Kernel (maths) in Vex

    Thank you but I've already saw and dig those posts except for the thesis, I didn't knew about this and it's awesome, thank's a lot !! The big advantage of the method I try to implement is that it finds areas where the fluid is highly stretched and it adds particles there, so you don't loose the great amount of detail (with droplets etc..). I've already found a solution and I came up with this : but the thing that bothers me is that I have a really tiny amount of droplets and some really long tendrils that are not that beautiful... and the fluid is expanding infinitely and I didn't found yet a solution to this. Cheeeers, thin_sheet_test.hipnc
  15. Implement Kernel (maths) in Vex

    Just tried to edit the previous code for a better implementation, but I'm still sure I miss a lot of things.... int pts[]; float kernel_result[]; pts = pcfind(0, "P", @P, ch("search_radius"), chi("search_count")); float kernel(int a, int b, float c){ vector pos1 = point(0, "P", a); vector pos2 = point(0, "P", b); float sum = 1 - pow(length(pos2 - pos1), 2) / pow(c, 2); if(0 <= length(sum) <= c){ float result = sum; } else{ float result = 0.0; } return result; } for(int i = 1; i < len(pts); i++){ float radius_mult = ch("radius_multiplier"); float radius = @pscale * radius_mult; float sum = kernel(pts[0], pts[1], radius); if(0 <= length(sum) <= radius){ float result = sum; } else{ float result = 0; } append(kernel_result, result); }
  16. Hey, why not use a copy stamp with a switch node with a variable called copy with this expression : round(fit01(rand($PT), 0, 11)) and then reference stamp("copy1", "copy", 0) in the switch node ? May be much simpler Otherwise check this video :
  17. Python export flipbook as mp4

    Hey, I've written a shelf tool to create flipbooks with custom parameters, and I want to know if it's possible to export it as mp4 once it's finished ? I tried with the flipbook_options.output() but it's exporting a video for each frame (so an image sequence), and I don't want to export an image sequence, but directly a video, if it's possible ! Cheers,
  18. Python create a list of cameras

    Finally I found the solution : camera = hou.ui.selectNode(node_type_filter = hou.nodeTypeFilter.ObjCamera) Cheers,
  19. Python create a list of cameras

    Hey, I try to create a shelf tool to add parameters to a camera, but I what I have created doesn't work. I try to get a list of the cameras, and then create a pop window with this list to select one of the camera, but hou.ui.selectFromList() doesn't read my list. Here's the code : #Choose the camera cameras = hou.node("/obj").glob("cam*") camera = hou.ui.selectFromList(cameras) print cameras Cheers,
  20. Snow Volume Shading

    Hello guys, I try to shade a snow simulation by rasterizing the points to a volume and use the pyro shader to shade it. I'm pretty happy with the result but I want to add some random brightness (to get some voxels reflecting light a lot and some not) to get a better look of the snow, but I don't know how to do this. If anyone has an idea or know where to start, I'll be glad to hear you ! I already tried to use a noise in the volume to use, but it's really really heavy and long to compute. I also tried to transfer brightness from random points but it didn't work at all, maybe I was doing it the wrong way. Cheers,
  21. Point Replicate SOP is moving my points

    Finally I found out a solution : use the upres sand shelf tool But under the hood, what was causing a problem is that the points where reorienting themselves alone, so by creating a vec4 orient and set it to (0,0,0,1) they don't move anymore ! Cheers,
  22. Hey, so I try to upres a particle simulation by using a point replicate, but the replicated points are moving, like they establish themselves in their real positions, as you can see in the gif : Anyone has an idea on why this is happening ?
  23. Keeping RBD pieces from falling off

    Try to increase the stiffness of your soft constraints, and create chunks of very strong glue constraints !
  24. Can't Get Field Force To Work

    Use an enable solver in your dop setup, and just set it to work on a given frame
  25. Advise Please- Buying new desktop optimised for houdini

    Two months ago I buyed a pc for Houdini, and I'm pretty happy with it, I have : - Ryzen 7 2700X - Corsair H150i - MSI X470 Pro Carbon - RTX 2080 MSI Aero - 4 * 16 Go DDR4 Corsair Ram - 970 Evo 250 Go for Windows and Softs - 6 To Seagate Barracuda for files (I'm thinking about investing some money in a nas for the future, and more SSD's) - Corsair Carbide 270r - Be Quiet! Straight Power Gold 750W It's pretty fast, stay cool when simulating or rendering (cpu doesn't exceed 60 degrees at 100% of use), but it's doing a bit of noise (which doesn't bother me when I'm sleeping), for a total cost of 2600 euros. I know I missed the 3900X and the rtx super series but I'll upgrade later. What I can advice you is to take the max ram you can, and one gpu to begin seems honest. With redshift 2.6, my 2080 does the job nicely and fast. I suggest you to go with the new Ryzen 9 3900X, 128 Go of ram if you can afford, and a 2080 Ti. This would be a nice pc for Houdini