# Daniel

Members

118

## Community Reputation

0 Neutral

• Rank
Initiate
• Birthday 02/24/1969

• Website URL
http://

## Personal Information

• Name
Daniel Kramer
• Location
LA
1. ## laplacian deformation?

After playing with the deformer in Blender, it's quite different than Delta Mush. A bit hard to describe but it almost feels like it creates an ik relationship between all the edges in the mesh.. with just anchoring a couple of verts on either side of a mesh and pulling them apart it smoothly interpolates the verts between them using the connectivity of the mesh in a natural way. There is code for the deformer on the Blender repository, might be worth trying to port
2. ## laplacian deformation?

Hmm, Probably is. It's also similar to the Edit sop when using a smooth radius by connectivity. But I'm interested in seeing how this works as a live deformer, not an interactive sculpt. I'll see if I can do it with delta mush
3. ## laplacian deformation?

Has anyone created a "laplacian" deformer in Houdini? Or maybe some of the current deformation techniques use this under the hood? Blender has this and it looks interesting:
4. ## VEX or Python Intersect with specific prim?

Not exactly. I want to move the point along the normal of the plane defined by the prim. So imagine my triangle represents and infinite plane with a normal. I'd want to move the point along that normal until it hits the plane and record the barycentric coord and distance offset to the plane. So it may miss the triangle completely but it would hit the imaginary plane it defines. I was going to scale up the triangles really big before the test to "catch" all the intersections but I may just have to code in the math for a line/plane intersection and do that myself
5. ## VEX or Python Intersect with specific prim?

Hello, Dusting off my Houdini hat after many many years. I'm trying to take a set of points and intersect them with a set of triangles. But I only want each point to intersect a particular corresponding triangle. So I have 500 points and 500 triangles, I'd like pt1 to only intersect with prim1, pt2 to only intersect prim2.. etc. etc. I'm generating the triangles in question within a python sop but I don't see a way to intersect a point with the triangle.. I'm not seeing any interaction funcs in the hou py module. I realize there's a vex intersect but I don't think it allows you to intersect a point against just a specific prim from an input. I know this can be done in the HDK but I'm just trying to prototype something quickly. I could do some sort of copy/stamp loop and isolate the point and prims but ideally I don't have to do that. Any pointers? Thanks Daniel
6. ## HDK vs. Python

Thanks Simon, I'll take a look. Been out of the loop for a long time. I currently have an interesting node running in python and it does need to be faster, so going to weigh my options. That Cython looks interesting as well. One thing I learned while working with HOM is if I update a module I'm sourcing while houdini is running it doesn't pick that up, a restart of houdini appears to be needed (unless there's some sort of flush command that I need to run?)
7. ## Force Cook from Python Node?

Just to follow up, the cooks are working correctly and no forcing was needed. The only issue I have now is a redraw issue. I'm updating some params on my python node and I have other objects referencing those params. When I play though my anim the objects referencing those channels always draw 1 frame behind.. if I stop the playbar and select an object then a redraw happens and my objects snap into place. The channels are always right, it's simply a ui redraw thing.. I'll see what I can do to figure that out
8. ## Surf's Up

Erik, this is great. I was the supervisor in charge of designing the Surf's Up Waves and did a bit of the work myself. It certainly brings me back to see your tests and how well you've replicated the basic design and look, very cool. It looks like you have most of the key concepts working, I'm guessing you've already read our Siggraph presentation, but if not there's a lot of good info in there: http://www.imageworks.com/ipax/docs/Siggraph2007SurfsUpCourseNotes.pdf I wish we were able to build it all in Houdini. Most of it was built into maya with a lot of custom plugins, our waves needed to be animated by animators, not fx artists, at our Layout stage.. long before fx traditionally gets into the mix. D
9. ## Force Cook from Python Node?

Playing with writing a python node, which is fun. I'm doing something somewhat unusual probably where I've got an iteration loop inside my operator.. within that loop I update some of the params on my node. Other objects in the scene are referencing those params so as my iteration runs I would expect those other objects to react to the ever changing values. I don't think the cooks are happening though (at least I don't see them react in the ui and the results don't appear to show that either). Is there something I can put in my loop to force a cook or update? What I'm doing probably doesn't fit inside a node context very well, There's probably some other pythony panel or something I can build my loop into (since my node doesn't take any inputs or outputs directly.. just a holding place for code and a ui) Thanks for any pointers D
10. ## HDK vs. Python

I'm guessing this has been talked about before but I'm a little late to the party and I'm not seeing any threads at the moment (but being a bit lazy too). I haven't used houdini hands on extensively since h8 and figured while I have a little time I should take a look at what I'm missing. HOM looks very powerful as it appears to have many of the features that you used to have to go to the hdk to get. So I'm just trying to figure out when it's worth going with HDK or HOM. My guess would simply be speed, I would guess the HDK would be faster but I don't want to assume that. I'm also guessing the HDK is more flexible in the end and HOM probably only supports a subset of what you can do in the HDK. Just want to get your impressions after using both for a while now.. If a sop can be built in HOM is there a reason not to? thanks D
11. ## Monster House Render Software

I'm on vacation or I'd help. If you get the test up and running I can probably find a person to help (or test when I'm back at work.. but that's not for 3 weeks) D
12. ## Monster House Render Software

Maybe you can just mail the guy who produced those tests and see if he'll send you that model? D
13. ## Monster House Render Software

Sony bought the source code but Marcos is still free to sell the software. There are specifics and limitations that I won't go into here about that deal (partly because I don't know all the details and don't want to compromise any confidence) Yes, Cloudy was rendered completely in Arnold (sans some efx elements) which has now become our in-house renderer. We've got a team of very talented software engineers who have dedicated themselves to making Arnold production ready. Lighting the movie with Arnold was a pleasure and it would be very difficult to go back to a scanline renderer at this point. Features like hair and motion blur have been greatly improved over the course of Cloudy. D
14. ## Setting parameter values from within a node

Hey Guys, I have a node I've written that does some cooking and outputs the answer to some float parameters on the node. I then reference that parameter from other nodes using a simple ch() func. I have an internal cache (stl vector) of the solved values per frame. After going to a frame if it's unsolved I go though a solving loop, otherwise I set the cached value for that frame directly . This all works well but if I only display the nodes which reference these channels they don't update properly. These other nodes are requesting the channel val from my node, but since my node doesn't "cook" it returns whatever happens to be in the float field. My node has no inputs or output wires.. it's all though ch() references that it communicates to other nodes. I'm guessing I need to make it a channel function (like raw() which seems to have disappeared in H9?). Rather then have an internal cache that's of my own design it would probably be better to use some houdini convention for this so it plays nice with the rest of the cooking scheme. Well, if that explanation wasn't too confusing.. any ideas on what the "right" way to do this is? thnx Daniel
15. ## Guide Geometry Color?

BTW, if you guys do figure this out, I'd still like to know. I'm not sure if prim colors would work Jason, maybe in the absence of Cd it picks a default color, but with it you can override.. hmm.. have to try it (that'd be too sensible!) D
×
• Donations