Deborah R. Fowler
Houdini Troubleshooting
Posted Dec 13 2017Updated on June 24 2024
WINDOWS 11 NOTE - If your geometry disappears
RENDERFARM ISSUES see troubleshooting on the renderfarm
REDSHIFT ISSUES see my page on Redshift
If it is an OpenGL issue (Geometry not showing up) it is either out of date drivers or the NVIDIA GE Force Experience not being set to Studio Drivers - described here
Generally speaking, walking up and down the node network with the display node is the best way to debug your networks in Houdini. What do I mean by that? Houdini is non-destructive - all your history is there. As Jeff Wagner put it, you can "change anything - anywhere - anytime"
This allows you to work your way up the network and see where/when something has gone wrong.
- Working modularly is extremely important in life, not just Houdini. If a job is too big to tackle, break it into smaller tasks. The process of debugging or troubleshooting is similar. Isolate the problem. To do this, you can also create sample files to test a node for example.
- Trust but verify - these are not just clichéd sayings. If you think a node is doing something correctly, confirm and also on the negative side - if you think a node is causing a problem - confirm - bypass it and see if it goes away, try to reproduce the problem in a simple case.
- Isolate. Go the the place you suspect the problem might be - that is what experience is - knowing where to look first - eliminate red herrings - narrow it down to the exact place - prove it. Don't assume , narrow it down and show that it is broken. From there you can solve it.
Also do not trust the GL viewport - always render to Mplay or command line to confirm.
Remember to check the Geometry Spreadsheet
Common Problems:
- Not able to write to the license file on Windows 10?
run Houdini as administrator
- You can set this to be the default behavior (right click on the icon to select this option)
- Under Compatibility tab check off "Run this program as an administrator"
- Wrangles - if you change the name of a node the reference in your expression in point wrangle does not auto update (hscript does)
- No copy node? Check that you are in SOP or what is called Geometry context, not in obj
- As of Houdini 19.5 they have hidden the copy stamp node from the tab menu - you can easily retrieve it from the textport window (use Technical desktop setup) and type
- opunhide Sop copy
- alternatively you could type
- opcf /obj/geo1; opadd copy
- in the above, geo1 could be whatever your container node is called
- colors disappearing when you pack? Make sure on your shader you have use packed color
- materials disappearing? Corollary to the above: If you materials are still not showing with packed, DO NOT unpack, set your Rendering/Render property to Save All Materials in your mantra node
- Boolean not working? Ensure that you are not
feeding in already packed geometry. Also, check that you
are feeding in solids, and if not, change the property to
surface. The behaviors of the boolean will be different for
these settings. Hipfile to
examine here (created in H18.0.499).
- Glass (principled shader) in mantra Glass not giving
transparent shadow? Turn on Fake Caustics to ensure you have
transparent shadows of the glass object
- Glass appearing shattered in the render before impact? As
of Houdini 18.0 this has been taking care of but there are a few
steps you have to take. I used this in 18.0.287 with my
platonic solids study.
- I created an example file that uses the material fracture
node at the bottom of this page http://deborahrfowler.com/HoudiniResources/RBD-PlatonicStudy.html
- However, the material fracture node is not required, but what is required is an RBD Connect Faces SOP as well as a RBD Disconnect Faces SOP with the mode set to Delete Connected
- I have create an example file in H18.0.499 glassLooksBrokenFix.hipnc
- This is discussed in SideFX documentation at https://www.sidefx.com/docs/houdini/destruction/glass.html
- Motion Blur adjustments needed? Remember to
check on motion blur in your mantra node and velocity blur on
your object container node render tab options.
- Motion blur settings come into play in particular with compositing elements of Maya and Houdini - be sure to match using forward, backward or mid motion blur frames (Shutter Offset parameter on mantra node).
- Our current peer tutor also suggests if you want to adjust a motion blur effect after the fact, you can manipulate the velocity. Excellent tip Felipe.
- Below is a comparison with blur manipulation mentioned above. Left is regular velocity blur, right I have increased blur by 2x. Example file manipulateMotionBlur.hipnc
- Motion Blur optimization using Motion Factor (in the mantra Dicing tab) - Example file manipulateMotion Factor.hipnc
- for object super blurry you can reduce render
calculations by using Motion Factor - below is a quick
example with motion factor 0 and then motion factor 3 giving
11 to 1 sec results.
- Motion Blur on camera can be controlled in the camera
tab shutter value (different from the shutter offset)
- Simming even though cached? Ensure load from disk and
display is on file or filecache node. See caching section
