Houdini Stupid Questions

From bernie's
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Sometimes I struggle with stupid stuff, I'll answer to my own questions here. I'm still learning as I go so if you see something that's downright wrong or silly, email me! bernie at berniebernie.fr


How do I layout nodes nicely?

  • A + drag in a direction with mouse: align nodes
  • shift + drag node: move all nodes above current selected one
  • ctrl + drag node: move nodes below

How do I change a transforms rotation axis easily ?

Can't be done 'easily' AFAIK, you can however right click the manipulator tool to change axis pivots

How do I pin an object to an another in Geometry/SOP context ?

  • (use point deform with a single point?)

How do I get the start/end frame of an alembic read in python?

   from _alembic_hom_extensions import alembicTimeRange as abctr
   startFrame,endFrame = abctr('F:/filepathto/alembic.abc')
   print startFrame,endFrame

Why doesn't my grain wire solve work?

Check that you have:

  • @restlength on the curves (prims)
  • in the dopnetwork, Emission type: All Geometry
  • each point needs to have @targetstiffness and an attr to drive the 'animated' point (@targetweight for instance) -- then in a pop wrangle:
   if (@targetweight==1) {
    v@targetP=point(0,'P',@id);
   }

How do I scale manipulators viewport size (like +/- in maya)?

/ and * (be warned that + and - change smooth mesh preview like 1 and 3 in maya)

How do I scale uniformely using the gizmo ?

How do I interpolate motion between still frames

I might be missing something super simple because this seems unreasonably complicated

v0BqBWl.png

  • The trick is to use floor($FF) in the timeshift rather than $F otherwise you get frame jumps on half-frames
  • So 1 timeshift with floor($FF), one with floor($FF)+1, plus a blendshape with $FF-floor($FF)

How do I instance a node (reference copy)

  • ctrl-shift-alt drag nodes

How do I combine (easily) loads of vdbs

Thanks to esteemed friend&colleague Charles

  • Make sure 'Flatten all B into A is on and your vdb (source A) is the same rez

qcuClGv.png

How do I cleanly retrieve vertex info to point (like laying layout UVs in world space)

3td2zkw.png