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Everything posted by catchyid

  1. hi, I have a digital asset that has menu A and menu B --> I use "Menu Script" to generate dynamically the contents of each menu, however I have this dependency : Menu B contents depend on A (so if user changes menu A selection, menu B needs to dynamically regenerate itself). Currently the only way to "refresh" menu B when A is changed is to manually select Menu B which calls its "Menu Script" (counter-intuitive for end user!). So my question : is there a way to force Menu B to run its "Menu Script" when Menu A is changed?
  2. how to update a menu items (not using menu script)

    Thank you guys I've tested calling back the menu pressButton() function and does is exactly what I want I have not tested the first solution bc my knowledge with hou.ui is limited... Once more, thank you guys for your help
  3. how to update a menu items (not using menu script)

    B only gets update when I click on it (to display its items). So if A changes, B won't until I click on B
  4. how to run a bash command and show result to user?

    what can I say , thank you is not enough , really appreciate your help thx
  5. hi, houdini 17.5, linux, python 2.7 (the version that ships with houdini :)) i want to launch a hython script in a shell (e.g. xterm) and show its progress to end user (basically, I need to show to artist the progress of this script, also, I want this xterm to be independent of houdini, meaning, if the user shuts down houdini, i want xterm to be running and finishe the job). I am new to python, so I checked quickly and found a way to use subprocess.Popen(['xterm'],stdout=PIPE,stderr=PIPE) which starts a shell, but could not find anyway to send the command (e.g. my hython script) to the shell (tried process.communicate, ...but nothing worked!) I am thinking, maybe there is another ready to use gui/API in houdini to allow that? note: i don't want to use "run in the background" in file cache node because I need to run a script, plus i might run multiple instances of the same script (each one is doing processing different part of the hip file, it's all done on the fly, so I don't even know how many file cache node I need) Thx
  6. hda to get called back when hip file saved?

    thaaaaaaaaaaaanks Drew
  7. hi, I am developing an hda, and some of its parameters need to update themselves when the file is saved (e.g. if the user changes the file name, then i need to run a code in hda to update some paths accordingly). I found some event handlers (e.g. on Created, On Loaded, ...), but could not find a handler such as (On File Saved?) ... thx,
  8. Hi, When I create a digital asset, I go to Scripts->OnCreated() method and write some python script to change some parameters in the newly created digital asset, HOWEVER, I don't know the name of the asset, hence I don't know the path to any node inside the digital asset? When I type hou.pwd(), I get "obj"... Thanks, onCreated.hip
  9. using packed primitives did it, thanks everyone
  10. Hello, I have some "transforms" (similar to maya locators) to be read in a rendering software. Is this possible? I can export easily points but not transforms? Thx
  11. vdb combine produces "errors" in combined volumes

    hi Karl, I am using 17.5...it's an older houdini version, so I assume it should be OpenVDB 7.1.0, however, I am pretty confident now that vdb merge in this houdini version as well is buggy: when exporting each cloud alone I get good render, when I merge all clouds I get flickering and bands...maybe it was not noticed/reported in houdini 17.5, but i think it's still there... thank you Karl
  12. Hello, I have 4 cloud vdbs that I combine at the end using vdb combine. The problem is if I render each cloud individually they look right in rendering, however if I combine the four in one big vdb the render looks "almost" perfect, meaning some areas could flicker for couple frames then go back to normal? has anyone experienced this problem before? the only solution now is to export each cloud independently instead.... thx
  13. vdb combine produces "errors" in combined volumes

    thx, will check that node to see how it works...i am using vdb for fog, so i am not sure a SDF function would work, anyways, will double check, thx
  14. Hi, Would increasing bullet sub-steps improve stability (I think will just give more "resolution")? same for constraints sub-steps? What should I except from increasing sub-steps specially for constraints sub-steps? I know that bullet has continuous collision detection so we will have "right" collision regardless of the simulation step length? Also, are there any guidelines or good numbers for sub-steps? defaults are 10 and 10, are they good? Finally, why there are two sub-steps : one for bullet sim and one for constraints? for example, If I increase bullet sub-step, would it automatically increase collision sub-steps as well? Thx
  15. break dop constraints in python dop solver

    did some investigating, it's possible to break constraints also but they must be attached to objects (and not the generic relationship subdata), attached file is an example if someone is interested pythonrbdscript.hip
  16. Hi, I am using Script solver inside a DOP RBD bullet sim, I was able to change velocities of individual RBD packed objects, however I don't know how to access/modify constraints network parameters (e.g strength, add/remove broken group, etc.)? The constraint network in defined globally "Relationships" subdata (i.e. not attached to each object), below is the code I am trying to write : from __future__ import with_statement def solveForObjects( solver_data, new_dop_objects, existing_dop_objects, time, timestep): dopsim = solver_data.simulation() relationships = dopsim.findRelationship("constraintnetwork1") constraintsnetwork = relationships.findSubData("constraintnetwork") # geometry lives inside 'constraintnetwork' subdata geo = constraintsnetwork.findSubData("Geometry") #that works, but it's not a hou.Geometry that can be edited! with constraintsnetwork.editableGeometry() as geo: #error: AttributeError: 'DopData' object has no attribute 'editableGeometry #.... do something here
  17. pieces explodes once constraints break?

    nope, even if pieces are intersecting intially it won't blow up bullet --> i fixed it, but the fix was super "silly" --> just use the default values for bullet ! (the one that was causing the issue is rotational stiffness, when i set it to default, things got back to normal)
  18. hi, in a bullet solver, once I break the constraints between pieces they fly super quickly in different directions, any idea why? thx
  19. pieces explodes once constraints break?

    yet another update: i applied the same setup on a simple box and it work ... so my guess is : i am destroying a bridge model and there are many intersecting pieces (actually some pieces are 80% inside another pieces), see image, so when constraints break pieces fly fast, hence the explosive behavior...will verify
  20. pieces explodes once constraints break?

    just an update: i increased/decreased collision padding on the packed rbd object but still the same explosive behavior ??
  21. hi, in a bullet solver, once I break the constraints between pieces they fly super quickly in different directions, any idea why? thx
  22. Workflow for RBD fracture/destruction

    thx guys
  23. Hi, This is an open question on workflow for RBD fracture/destruction. I have a bridge where it gets destroyed by a magical force (i.e. pieces must initially fly in predefined directions). In addition, I want be able to control pieces sizes when they get initially detached from the bridge, and when big pieces hit the ground they should break further. Couple challenges here: (a) deattach pieces in bug chunks, (c) control their initial velocity (for 1 or 2 frames right after they deattach), (b) break big chunks when hitting the ground. (by 'chunk' I mean pieces constrained together using glue constraints). So far I have tested two workflow : a ) Use built-in RBD Material node to create hierarchical fracture, use other built-in nodes to constraint pieces together, and apply a deformed static object to break the bridge. However, when I do so : (1) I have no control over the pieces initial directions, and (2) it will be super difficult to control how pieces break in a hierarchical way such that big chunks break first then when hitting ground they break further (e.g. measure constraints impulses, compare to constraints strength, adjust, retest) ==> This workflow seems hard/near impossible to control b ) Still use houdini nodes to fracture pieces, but then rely on vex code/logic to break pieces (i.e. no static deformed collider), cluster big/small pieces, break constraints further when chunks hitting the ground (i.e. check collision with grounds and break more constraints) --> this is working but painful to write!! I am wondering what other artists/TD do when they have super artistically controlled destruction? Thanks
  24. [Houdini 17.5.173] I have solid mesh with holes in it. I use RBD Material Fracture to break it (concrete mode), however : 1) If I don't enable "Detail" option, it works correctly 2) If I enable "Detail" option, I get bad geometry? Seems like a bug in Houdini! Has anyone managed to find a workaround? The only workaround it to fracture massively and glue pieces but this is a heavy solution? Thanks, fractureTest_DeatilsProblem.hip
  25. RBD Constraints from Rules

    hi, plz ignore previous question another question below: Question: why constraints are not coming from the same center of mass as the previous constraints? rbdfromrules_2.hip