Found 422 posts.
Search results Show results as topic list.
Houdini Lounge » Houdini Crowds: Orient different crowdsource nodes
-
- cwhite
- 793 posts
- Offline
I'd suggest submitting an RFE for this. It might be a useful addition to something like the POP Steer Align DOP.
Houdini Learning Materials » Easiest way to convert ~500 '.obj' files to '.bgeo'?
-
- cwhite
- 793 posts
- Offline
You can use Houdini's gconvert command line tool to convert between formats (e.g. ‘gconvert file.obj file.bgeo’)
Technical Discussion » RBD help with glue constraints.
-
- cwhite
- 793 posts
- Offline
The default expression for the Overwrite with SOP parameter on the Constraint Network DOP is evaluating to 1 on each frame because the SOP node is time-dependent, and this keeps overwriting the constraint network from the SOP path.
The time dependency comes from the use of $F on the file cache SOP, so you could either adjust that or change the Overwrite with SOP expression to $SF == 1 to only import from SOPs on the first frame.
The time dependency comes from the use of $F on the file cache SOP, so you could either adjust that or change the Overwrite with SOP expression to $SF == 1 to only import from SOPs on the first frame.
Technical Discussion » RBD dangling object
-
- cwhite
- 793 posts
- Offline
Looking at the guide geometry, the pairs of constrained points are flipped around - this causes the twisting at the start. I created an ordered point group to get the pairs in the expected order.
Technical Discussion » RBD dangling object
-
- cwhite
- 793 posts
- Offline
Technical Discussion » RBD bullet, unable to get substeping
-
- cwhite
- 793 posts
- Offline
You should use animated static objects rather than deforming static objects in this situation (and move the transform SOP after the Pack SOP so that the packed primitive has an animated transform).
Since rigid bodies can't deform, the solver sees them as teleporting from one frame to the next. You'd need to increase the DOP network's substeps to get decent results.
For animated static objects, the solver can interpolate their transforms on each of the substeps.
Since rigid bodies can't deform, the solver sees them as teleporting from one frame to the next. You'd need to increase the DOP network's substeps to get decent results.
For animated static objects, the solver can interpolate their transforms on each of the substeps.
Technical Discussion » RBD dangling object
-
- cwhite
- 793 posts
- Offline
With a constraint network, you could use a point anchor (see the Anchor Types section of http://www.sidefx.com/docs/houdini16.0/nodes/dop/constraintnetwork) [sidefx.com] to constrain an object to a particular point on another DOP object (like a wire object).
Depending on your needs, it might be simpler to use a single solver to simulate the entire system. The wire could be composed from multiple RBD objects with constraints that allow bending. Alternatively, the dangling object could be simulated as a wire object to allow the wire solver to be used for the entire simulation (the Pendulum example file in the documentation demonstrates this)
Depending on your needs, it might be simpler to use a single solver to simulate the entire system. The wire could be composed from multiple RBD objects with constraints that allow bending. Alternatively, the dangling object could be simulated as a wire object to allow the wire solver to be used for the entire simulation (the Pendulum example file in the documentation demonstrates this)
Technical Discussion » Crowd Simulation : Maya - Houdini - Maya
-
- cwhite
- 793 posts
- Offline
You could write out the agents to Alembic, but that would produce a huge amount of geometry for any deforming shapes as mentioned in the previous post. Another idea would be to just export the agents' joint transforms if you're able to do render-time deformation in whatever renderer you're using.
Mantra's agent procedural does render-time deformation, along with some additional LOD-based optimizations (http://www.sidefx.com/docs/houdini16.0/nodes/shop/vm_geo_agent) [sidefx.com]
Mantra's agent procedural does render-time deformation, along with some additional LOD-based optimizations (http://www.sidefx.com/docs/houdini16.0/nodes/shop/vm_geo_agent) [sidefx.com]
Technical Discussion » Houdini keep on crashing while loading custom HDK plugins!
-
- cwhite
- 793 posts
- Offline
My guess would be that compiling plugins with gcc 5.4 is responsible for the crashes - Houdini is compiled with gcc 4.8 in accordance with the VFX platform
Technical Discussion » Compound geometry Bullet body doesn't work
-
- cwhite
- 793 posts
- Offline
cgbeigetamte
you can just use Convex mode and check Create Convex Hull Per Set Of Connected Primitives on RBD Packed Object
unless you really want to create compound shape just from primitives
This doesn't seem to create collision meshes that respect concaves, which is why I wanted to use compound, which is meant to work with concave meshes
I'm not sure why you expected it to work for concave meshes, since the docs (http://www.sidefx.com/docs/houdini16.0/nodes/dop/rbdpackedobject) [sidefx.com] indicate that it's only for simple primitives. It sounds like you want a convex decomposition tool?
Technical Discussion » Compound geometry Bullet body doesn't work
-
- cwhite
- 793 posts
- Offline
No, the solver only inspects bullet_georep on the top-level packed primitive. If it's set to convex hull, then for each group of connected primitives (if that option is on) it'll build either a convex hull or a more optimal collision shape like a box or sphere
The compound mode is a little more like what you're describing, though it only supports primitive shapes.
The compound mode is a little more like what you're describing, though it only supports primitive shapes.
Technical Discussion » Compound geometry Bullet body doesn't work
-
- cwhite
- 793 posts
- Offline
tamte
thanks, for primitives that makes sense, but what about box or plane? those are not primitives, will it detect automatically from polygonal shape?
For boxes, it looks for six polygons that form a box shape (roughly the same approach as the Bake ODE SOP). This means that the default box will get the optimal collision shape, but for anything more complicated (like if the Axis Divisions parameter was used) you'd want to switch from Convex Hull to Box to get an auto-fitted box shape.
If the geometry has an SDF representation attached that is set to Implicit Plane, then a ground plane collision shape will be used (this is how the Ground Plane DOP works). Otherwise, you can also get a plane shape by switching the representation from Convex Hull to Plane, which “auto-fits” a plane by using the first primitive normal it finds.
Technical Discussion » Compound geometry Bullet body doesn't work
-
- cwhite
- 793 posts
- Offline
tamtecwhitesounds great, I wonder how that works
… In that mode, the solver will still auto-detect boxes, spheres, tubes, and c-regions (capsules),…
Does it detect it directly from the shape?
Or does it rely on bullet_georep attribute to be present?
Yeah, the convex hull mode will use more optimal collision shapes where possible based on the object's geometry. If, for example, the geometry (or the primitives in one connected component if that option is enabled) consists of a single primitive sphere, the solver will use Bullet's sphere collision shape instead of converting the sphere to polygons and using its convex hull.
Technical Discussion » Compound geometry Bullet body doesn't work
-
- cwhite
- 793 posts
- Offline
tamte
you can just use Convex mode and check Create Convex Hull Per Set Of Connected Primitives on RBD Packed Object
unless you really want to create compound shape just from primitives
Yeah, that is the best way to go. In that mode, the solver will still auto-detect boxes, spheres, tubes, and c-regions (capsules), so you can get the exact same results as the ODE compound workflow without needing extra setup, and it'll also handle convex hulls.
Technical Discussion » How do you modify the orientation and add __locomotion__ speed to an Agent, and then write that out via Agent ROP?
-
- cwhite
- 793 posts
- Offline
I'd suggest filing a bug for the errors with the scene FBX importer - adjusting the animation on the source character rig would be the easiest workflow for this type of scenario.
The Agent Edit SOP just modifies the current transforms of an agent's joints, and doesn't modify the animation clips (which are shared between copies of agent primitives). That's why writing out the agent definition with the Agent ROP doesn't change anything.
You could bring the animation clip into CHOPs via the Agent CHOP, and then use the Agent Clip SOP to add the modified clip to the agent definition.
For your second question, you can use the Agent Layer SOP to add new sets of geometry to an agent
The Agent Edit SOP just modifies the current transforms of an agent's joints, and doesn't modify the animation clips (which are shared between copies of agent primitives). That's why writing out the agent definition with the Agent ROP doesn't change anything.
You could bring the animation clip into CHOPs via the Agent CHOP, and then use the Agent Clip SOP to add the modified clip to the agent definition.
For your second question, you can use the Agent Layer SOP to add new sets of geometry to an agent
Technical Discussion » VEX Attribute name as string from channel
-
- cwhite
- 793 posts
- Offline
On the Bindings tab, add a binding and set the Attribute Name to reference your string parameter, and set the VEX Parameter to the name you want to use in the VEX code.
Houdini Lounge » Crowd Forming Specific Shape
-
- cwhite
- 793 posts
- Offline
You could use something like the POP Steer Seek DOP to guide agents towards particular goal positions, and then transition into an idle clip once they get close enough.
Technical Discussion » Freeze Cone Twist Constraint deformation
-
- cwhite
- 793 posts
- Offline
Technical Discussion » Foot plant automatic bone selection
-
- cwhite
- 793 posts
- Offline
It's just a preset that the shelf tool applies for the three built-in mocap HDAs. I'd suggest submitting an RFE to have the shelf tool be a bit smarter and remember the selection used when baking out previous clips for the same character.
Technical Discussion » Crowd: using non looping animation clips
-
- cwhite
- 793 posts
- Offline
Have you tried the Agent Clip Properties SOP? That allows you to set up some information that the crowd solver can use when playing back clips, such as whether to do some blending while looping around
-
- Quick Links