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Everything posted by symek

  1. VEX quaternion to vectors

    If by reverse you mean how to get original matrix (or N and up): matrix3 m = qconvert(@orient);
  2. Hacked site

    Oh, How pity. I discovered new sport today
  3. Hacked site

    Admins are on it.
  4. Limit Houdini RAM usage

    On Linux you can limit Houdini's memory with cgroups on kernel level. -j just limits the number of cores Houdini will attempt to use, but doesn't constrain memory access. Simplest way is to tune your sim as proposed by Atom. hth, skk.
  5. Substance plugin uses default Houdini material, which is not built from scratch either (plugin will pick up what ever comes with Houdini, you can also customize it - checkout Substance plugin config file, which specifies which material is to be used and its textures->parms mapping). Nothing fancy here. The same goes for Mari, albeit it is still a matter of figuring out whether mantra's principled shader is currently in sync with Mari default PBR (which is targeted towards Arnolds afaik). Either way, neither Substance nor Mari don't expect anything fancy. It's a beauty of current PBR pipelines, most PBR shaders do match (to the reasonable extend of BRDF implementations or falsely design of a particular shader obviously).
  6. Substance plugin for Houdini simply renders material into a textures and applies them on Houdini's standard shader. It's less flexible and somewhat more confusing than applying those textures by yourself. Shorty put, you don't need this plugin to work with Substance in Houdini. Some advantage is that you can manipulate materials parameters from Houdini UI without having Substance running. Practically speaking not so useful anyway. The same goes for Substance Designer. btw this is what all Substance users are doing, since even unreal plugin renders materials to disk as textures to pick up by the engine. Mari is the same story since it stores its output to a standard set of textures which can be digested by any renderer - you don't need any plugin .
  7. RAM cleanup

    ye, dropping cache requires sudo privilege, and helps only freeing memory allocated by kernel to amortize disk read, not belonging to Houdini process itself. Interestingly freeing memory used by Houdini might also be outside Houdini jurisdiction. Jemalloc might keep it even after Houdini deallocates it. It's a trade off for fast multithreaded malloc. As a side note, although I haven't looked into it much, it feels like a slowdown of Houdini in case of long sessions has more to do with viewport caches, GPU memory etc, rather them RAM utilization. If you render heavy smoke sequence cached on disk, after couple of minutes of jumping between frames, Houdini becomes slow, but only if you have a viewport open (at least last time I did it, which was a ~year ago). Maybe OpenGL driver doesn't free texture3d?
  8. Rendering Scene to another computer ?

    You typically install Hqueue client on second machine. It also has to have an access to Houdini installation, either locally, or via shared network storage. Hqueue documentation is quite thorough and describes installation and setup process. AFAIK you will need at least Houdini Indie license for every computer taking part in rendering.
  9. Controlling Focus Distance

    It's because adding Pz/Depth extra plane for Redshift works differently. Possibly camera parameter might have different name on RS rop. It's an easy fix if you have RS around (I don't till Monday, sorry). skk. damn you OSX with no X server anymore.
  10. Nvidia Flex implementation

    Flex doesn't give you anything more than what you already have in Houdini with Grains on OpenCL. It's only as fast as your updates of simulation - which usually involve CPU (meshes, volumes) in real scenario. It's good for games I suppose (specially that they support AMD and Intel finally), but in FX you will quickly get back to realm of ordinary people using DOPs with total control and directibility. Saying that, I have to admit that having even basic hair simulation working in SOPs in realtime while animating rigged character is super fun to watch. You can check my messy github account for wire solver in Flex. But it useless in current state (I have slightly better implementation, but can't share it, sorry, and it isn't very practical anyway).
  11. timeblend Orient Quaternion

    Does't "Smooth interpolate Normals, Quaternions..."option on TimeBlendSOP work for you? It should interpolate orient attribute. If for some reason it doesn't, you can use VEX's slerp function to tinker up own timeblend.
  12. Particle Exporter for Octane CSV

    Houdini doesn't store particles (or points) transform matrix explicitly, so you don't need any special functionality for it. You can make it by your self from: position (P attribute) optional scale (pscale attribute) optional rotation (orient attribute) Perhaps the easiest way is to use Make Instance Transform VOP inside AttributeVOP. It will create nice 4x4 matrix for you given the above (and possibly other) attributes are provided... Export it to a point attribute called, say, 'xform' and use Python to save subset of this matrix to a file (google says Octane stores 12 out of 16 floats of 4x4 matrix). Super easy (there are more elegant but verbose ways too): xforms = hou.node("/obj/my_particles/OUT").geometry().pointAttribValues('xform') xform is now a tuple of 16 x #particles floats, which can be saved to a file suitable for Octane. hth, skk.
  13. HQ server getting job ID

    I don't think jobid is saved anywhere in a scene / node itself. I guess you need to query hqueue server for a jobs recently submitted with API: http://www.sidefx.com/docs/hqueue16.5/help/api.html Alternatively you could add some logic to $HFS/python2.7lib/hqrop.py (or $HFS/houdini/soho/pythonx.x/HQRender.py maybe?) o retrieve jobid just sent.
  14. Great speech from Mark also. Totally cool.
  15. It's actually quite demonstrative attitude towards them...
  16. Render to pointcloud?

    Check out pcwrite function help for working example of such shader: http://www.sidefx.com/docs/houdini/vex/functions/pcwrite.html hth, skk.
  17. Houdini and hython/hbatch/engine is simple: hou.isUIAvailable() // spots the difference For python in Mantra filtering, check if you can import mantra module, and handle exception properly is_this_mantra_filter = False try: import mantra is_this_mantra_filter = True except: pass For python running inside HDA instanced by Mantra afaik it is less obvious. I can deduce it from a details like content of sys.argv. From what I see in Mantra case it's empty: import sys if not sys.argv[0]: # this seems to be Engine running inside Mantra pass highly unreliable. hth, skk.
  18. Create HDA using python

    hou.Node.createDigitalAsset() + 10 other hou.Node's methods dealing with hda.
  19. Yes. Use RAT texture. Mantra doesn't use tilling nor mipmapping in EXR format (even if file itself is tiled and mipmapped).
  20. Ubuntu will work minus graphic card drivers (better to switch to default video driver at old machine). Windows probably won't (at least it never was with Win7).
  21. Afaik HDK doesn't expose any headers for Mantra's camera, but you might take a look into lens shaders, like ASAD lens shader (v_asadlens shop) to control camera projection.
  22. kwargs in python shell ?

    print hou.node("/obj/myHDA").hdaModule().kwargs
  23. Is OpenCL 2.0 Faster than HFS OpenCL?

    You can always confront your imagination with reality measuring Houdini's performance in both cases. I wouldn't be surprised if lso OCL 1.2 code could run faster on OCL 2.0 driver. Aside of language's changes, new versions usually evolves compilation for better vectorization (I also imagine that dynamic parallelism might be used for work stealing).
  24. Maybe they have been bought?
  25. On a single computer, right? I don't see why not. You can always open multiply session of Houdini on a single computer without consuming license. Moreover, if you start hbatch on a computer used already by Houdini, it will not consume another license too. Shorty speaking Houdini will always consume a single license on a single node what ever number of processes are running on it given previously accounted license is sufficient to run new process (HoudiniFX + Houdini Core + hbatch running at the same time will consume single license, while hbatch + Houdini Core + Houdini FX, will except three distinct licenses...).