Jump to content


  • Content count

  • Joined

  • Last visited

Everything posted by tagosaku

  1. apply boolean twice problem

    hi, when I try to use a boolean node twice, second boolean result is always broken because I guess a connectivity issue. Houdini cannot understand the connectivity from first boolean result. I know some people says to cut together with many cutters, but I have a certain situation to cut separately. For instance first boolean produces 500 pieces, and keep 300 pieces and use second booleans for other 200 pieces, and so on. Some artist do after-1st-boolean > loop start > delete all pieces(groups) except one favorite piece > do-2nd-boolean > loopEnd > merge together. Or, I do translate and separate each other of pieces in order to make spaces between each pieces, then apply 2nd boolean, and it works I wonder if anyone knows smarter methods, instead of translating or looping booleanTwice.hipnc
  2. hi, I tried to use sourceVolume node as dynamics collision. So far, I tried the both of FLIP sim and pyro sim and can see a little bit influence, but it's almost not colliding at all. For instance with FLIP sim, I set: 1 - source volume > initialize > collision. 2 - check binding is correct. 3 - FLIP object > Guides > visualization > collision. I can confirm collision exists in viewpoint. The result looks almost zero collision. I knew this method is not accurate compared to staticObject method, but I could ignore a little lower precision. In fact, it's absolutely NOT acceptable result. On the other hands, when using staticObject, it always works perfect. Is this the exact reason that people combine to use staticObject node for collsionSurface and sourceVolume to add collsionVelocity? In conclusion, Have anyone succeed to use volumeSource as dynamicCollsion? What's differences of colliding mechanism between staticObject and sourceVolume?
  3. use sourceVolume node as collsion for flip and pyro sim

    To jamesr, Yes, I did. That's why I can see correct collsion shape in visualizer. Hopefully someone provides me a collision sample file of either flip or pyro sim...
  4. use sourceVolume node as collsion for flip and pyro sim

    hi, Peon Do you mean VDB surface won't work as collision with sourceVolume node? I tried pyro sim and FLIP sim with sourceVolume node using as static collsion, and I clearly see collision shape by FLIP/pyro object > Guides > visualization > collision, but it's not colliding very well. I guess a visualizer shows the exact collision shape but actual collision sim does not happen.
  5. hi, I have a question about pyroshader in houdini16. There are fire shading and smoke shading parameters separately. That's why I was thinking we could control alpha of fire and smoke separately, too. However, when I change general > smoke > Density Scale value, it influences to fire alpha, too. Then if I set the density scale to zero, actually fire alpha also becomes zero although fire's RGB shows red-yellow color. Thus questions are: 1 - what's the reason/concept we don't have a separate "fire density(alpha) scale" parameter? (Of course, we can separate fire and smoke by AOV with smoke_mask and fire_mask.) 2 - Let's say I need to create a custom shader for it. What kinds of two volume fields should I use for fire and smoke's alphas? Also, inside of pyroshader, there is a pyroshadercore node, which is an essential node but cannot be unlocked.
  6. Because I needed to reformat Windows7, I also reinstalled Houdini, and got strange UI. The node info is broken. Does anyone have thought how to fix? OS, hardware, videocard, and houdini version should be also same as before. I tried houdini 16.0.600,630, 504, but all same result.
  7. apply boolean twice problem

    it sounds boolean node is really designed to use once. Thanks for your tip. I will check it out!
  8. Because I needed to reformat Windows7, I also reinstalled Houdini, and got strange UI. The node info is broken. Does anyone have ideas how to fix? OS, hardware, videocard, and houdini version should be also same as before. I tried houdini 16.0.600,630, 504, but all same strange result.
  9. Yes, I installed SP1, but it happened. The solution was to reinstall windows from reformat again. The second round worked out. Thanks, guy!
  10. substep settings for dopnetwork

    Hi, I have substep setting questions when an object(emitter and collider) moves very fast. I am expecting to change 3 points: 1 dopnetwork > simulation tab > substeps 2 pyroSolver > advanced > min/max substeps I am not sure which one I need to change the above?? 3 emitter (collider) should be produced substep volume(denisty/SDF). From the volume/VDB, can we produce inbetween volume/SDF objects with timeBlend and/or attributeInterpolate? Or actually houdini will automatically handle all the substep sources?? I guess if meshes which are before converting to volume are able to create substep, FluidSOurce and VDBfromPoly nodes could create substep volume. But what if mesh is cached, what's happen? Ultimately, I believe ex-colleague showed me that he made a pyro tiny smoke, and created 4x slower motion post-smoke by somehow interpolating. Thus, if anyone knows substep settings and post-slowmotion voxel anim, I really appreciate it!
  11. expression for cache path

    hi, I have a question about filecache node. Basically I want to construct folders - project folder - HIP folder (save hip file here) - geo folder (cache here) I think 'project set' set $JOBS a file path, then we can use $JOB to make relative path. However, I try to skip that process because I don't like so much, also most productions don't use it. Then I use this expression in file cache node > geometry file `strreplace("$HIP/geo/$OS.bgeo.sc", "HIP/", "")` It seems to be working well, but I wonder if anyone knows a smarter way, let me know.
  12. expression for cache path

    umm, the result is not right..
  13. Hi, I am looking for auto-activation for source volume node in DOP based on an input object(VDB, houdiniSDF). This is because sim is broken, if the sourceVolume set to collision and there is no SDF primitive(@name=density or surface). So far, I tried 2 methods, but not working. A - use expression in activation, but something not right. B - use enableSolver, but probably it needs to place inside of the sourceVolume. If anyone has better ideas, please let me know, thanks sourceVolumeActivation.hipnc
  14. create auto-activation for source volume DOP

    I solved it by F1's help, thanks activation> (strcmp(prims("../../IN_coll", 0, "name"), "density") == 0) || (strcmp(prims("../../IN_coll", 0, "name"), "surface") == 0)
  15. I have a question about houdini cloth. I am looking for nCloth feature 'paint input mesh attract'. Basically I paint influences on mesh then attach an animated mesh which has same topology as nCloth's one. When siming it, nCloth mesh tries to follow the animated mesh as closely as possible. Non-influence vertexes are fully dynamics. Do we have a similar function in Houdini16?
  16. nCloth's input mesh attract for houdini cloth

    that's great. I will test it out, thanks!
  17. Hi, I am looking for expression to automatically activate source volume node in DOP by input object(VDB, houdiniSDF). This is because sim is broken, if the sourceVolume set to collision but there is no SDF primitive. my idea is that the inside of the node, sourcevolume > SOP solver(source_density)>objectMerge(fetch_density). After this node, I add primitiveWrangle: if(@name == "density" || @name == "surface") f@activeSwitch =1; then I made float parameter(activation), and paste expression. prim(".", "activeSwitch", 0) After that, I plan to paste the parameter value to sourcevolume>activation. Then it should automatically set activation ON/OFF. The wrangleVEX is working but prim's expression is not working. How can I fix it??
  18. prim expression for source volume activation

    Oh, I am sorry too that I just knew there are TWO expressions, "prim" and "prims" !! I completely misunderstood them. Thank you, f1, so much for providing a sample file. I am checking it out right now!
  19. nCloth's input mesh attract for houdini cloth

    Where can I find the node "Target Deformation" in Dopnetwork ?
  20. prim expression for source volume activation

    actually code should be : (strcmp(prim("/path/to/operator", 0, "name", 0), "density") == 0) || (strcmp(prim("/path/to/operator", 0, "name", 0), "surface") == 0) However, this method won't work because prim does not return density name but will return actual density value. I need to figure out different way.
  21. removepoint - basic question

    hi, I always use this removepoint vex as example; removepoint(geoself(), @ptnum) I just wonder if we have any other situations not to write 'geoself()' or '0' ? In other words, do we have different use of this VEX, instead of removing incoming points/particle?(I believe @ptnum is always like that, not other @XXXX, right?)
  22. removepoint - basic question

    thanks, then I just remember the simple syntax!
  23. Hi, I am a very beginner of coding and looking for a custom save shell by python. This time, especially I'd like to ask for how to replace ".comment." part. Example file is "fx_dest_vocity_v051.04.comment.hip" and a procedure is : 1 - click shelf dock 2 - show a popUpWindow and type a comment 3 - click the popUpWindow, close it, and a script replaces "comment" part and new file name is saved, for example, "fx_dest_vocity_v051.04.vel2xfaster.hip" my best guess is; fileName = hou.hipFile.basename() ## for instance, file name is "fx_dest_vocity_v051.04.comment.hip" hou.ui.displayMessage("type comments", variable ) ## save comment hou.ui.displayMessage.close result = re.search( "([0-9]{2})\.???????\.hip", fileName ) ## get comment part newFileName = fileName.replace( result.group(1), variable ) hou.hipFile.save(newFileName) ## new file name "fx_dest_vocity_v051.04.vel2xfaster.hip" I know it's so many broken lines, so if someone helps to rewrite it, it would be great, thanks!
  24. custom save python script - a very beginner

    F1, thanks for your quick reply. Whole codes are changed and I can understand 70%. That's ok, and I tried your code and working well. I would like to ask for two things, When typing comment and hitting 'enter key', it executes as cancel, but prefer to execute as 'ok'. Then I changed to default_choice=1 Is that correct approach? Second questions, Actually I want to sometimes add comment words, not always. For instance, sometimes name "fx_dest_vocity_v051.04.comment.hip" or "fx_dest_vocity_v051.04.hip" Then I tried to change your code, but messed up. (sometime it loses last two digit numbers in a condition...) Could you add the feature that I can save a file with blank text?
  25. Hi, I am looking for measuring volume by VEX and/or attributeVOP, instead of measureSOP node. Basically I have mega voronoi fracture model. After that, I want to apply for volume calculation with loop node and compile node. Key is that I cannot use hscript expression in measure>center with compile node. That's why I am looking for another method.