Deborah R. Fowler
Houdini Tips and Tricks related
to complex scenes / layout:
Posted 2013
Updated on Oct 11 2020
Files created by Deborah R. Fowler unless
otherwise noted. Click
the link or picture for the hipnc
Reminder: when experimenting with simulations to REDUCE TO A SIMPLE CASE, TEST, BUILD FROM THERE
Simple case files are faster to test - and remember to VIEW THE GEOMETRY SPREADSHEET
- Alembic files
- Flips and openVDB for
collision geometry objects (also works for RBD) (now
standard in shelf tool for flips)
- for flip caching tips see Particle and Procedural effects page under Fluids - liquid
- Instancing NOTE:
Packed Primitives/Alembics are the preferred workflow from H13
up however instances are still very useful (for example light
instances, as well as to help understand the concept of point
instancing which is not package specific - packed primitives
on the other hand are unique to houdini). With the
introduction of solaris and Houdini 18 ... instancing is back!
(check out the copy to points in the solaris context ... an
instancer node)
http://forums.odforce.net/topic/19401-copysop-packed-prims-vs-point-instance-procedural/ - Instancing Examples and Instancing Notes (see also packed primitives below)
- Use fast point instancing for geometry, full point instancing for lights
- Instancing light tip for rendering - use active radius to
reduce render time (enable to edit, disable to render)
- Miscellaneous fun (to be updated)
- Floating lanterns in the sky? particlesFloatingLanternsH13.hipnc
- Floating lanterns in the water? lanternsWithRippleMoreComplexH13.hipnc with an example ripple sop and also the ripplesolver. (ocean may be a better choice - see below)
- Floating lanterns on the new ocean in 12.5 and up? lanternsFloatingTipH13.hipnc with the ocean and orienting the objects to the waves if desired (note that the rendering is not set up in this sample file - take a look at the shelf tool for reference)
- Floating lanterns on the ocean in 15 (scatter node has changed, need node interpolate position to keep points stable) NewScatterAndOceanH15.hipnc See documentation at http://www.sidefx.com/docs/houdini15.0/nodes/sop/scatter. AND a new file for 15.5.632 with instructions below
Ocean for 15.5.632 ready for lanterns and
rendering- Packed primitives
- http://www.sidefx.com/docs/houdini17.0/model/packed
- under the Rendering/Render tab
parameter called Declare Materials can be used if
your materials disappear (valid in H18 as well - geometry packed
and lost your textures? Use the setting below)
- Particles
Snow
Globe tip - reverse your collision normals using a
point wrangle node (H17) @N = -@N
pop instance and interact (H17)
- Particles - Tips on rendering particles that look like water - Available but under construction!
- Rendering particles as points: refer to renderAsPoints.hipnc.
- Particles - grabbing information out of a particle node - attribute create example.
- see instancing examples for particles used for layout
- example comparing old pop networks (< 13) and new Particle Dynamics (>= 13) and using the pop wrangle node in wranglePop.hipnc example (vex otl here)
- pop curve pc follow (also see below in Student Examples)
pop Spin
-
Instanced
Lights on Particles updated to H18 - remember
to look at the other instance examples above, this example
uses the pop curve follow as above to create points,
instanced lights are added with active radius/attenuation
ramp and the instance object taken out of the shadow mask.
Teapots glow green and light is magenta so that each
contribution is visible. - particles and RBD collisions - required if you want bounce behavior see popInsideRBDStaticH15.hipnc
- RBD examples - refer to new section
- ParticleDynamicsRBDCollisionH13.hipnc
as show in class, pop collisions leave
velocity unchanged after collision, dops set it to zero - take
advantage of the pop and point wrangle nodes. Note: If instead we had an RBD collision in
addition to the ground plane, you may have to change the
comparison from hitnum to stopped as hitnum goes back to zero
in this case (see ParticleDynamicsRBDCollisionStaticOrNotH13.hipnc.
- Wrangle nodes (general) and other examples as well
-
@numpt and
@ptnum -
particles and
variation of color over time using wrangles or chops
-
particles and instanced lights!
Vary light types, or you can override the shader and animate
your light intensity -
using
the wrangle node to calculate angles (explanation here)
Fur Trees (explanation here)
-
- Vex/Vops and a little python
- Vex/Vops -
- bind node has replaced attribute in vops in versions 14 and up
- currently in H15 pragma range does not update gui - work around is to rename, apply accept, edit and rename back
- In Monty, you might need
to add the following to your .bashrc to view code properly
export HOUDINI_USE_HFS_PYTHON=1 - VOPS - customizing a simple shader.