Found 29 posts.
Search results Show results as topic list.
Technical Discussion » Copy transform SOP vary scale per copy (alternative to $CY?)
- Lyubomir Popov
- 29 posts
- Offline
Thanks, I resorted to a wrangle and did it all there eventually, but your way is nicer and simpler.
Technical Discussion » Split / shatter an arbitrary polygon using polylines
- Lyubomir Popov
- 29 posts
- Offline
Technical Discussion » Split / shatter an arbitrary polygon using polylines
- Lyubomir Popov
- 29 posts
- Offline
cncverkstadThanks, interesting assets, however I'm not looking to break up the line into dashes, I need to break up the shape into closed polygons I can then sweep profiles curves on.
Search For Baku89 on GitHub-dashed lines ..some Fun otl's there ..Have Fun
Technical Discussion » Split / shatter an arbitrary polygon using polylines
- Lyubomir Popov
- 29 posts
- Offline
Hi, is it possible to split the green arch in the screenshot into segments using the white lines? I've tried various combinations with polysplit (not working well inside foreach), using the boolean sop (not working at all as it tries to triangulate the poly), and using the labs boolean curve (again, tries to triangulate everything). Attaching the file.
Technical Discussion » Copy transform SOP vary scale per copy (alternative to $CY?)
- Lyubomir Popov
- 29 posts
- Offline
Thanks for the reply, but I'm not sure I understand - the Copy transform doesn't take points as input, just the geo to be copied.
I know how that can work with the Copy to points SOP, but was hoping to be able to just use the simple Copy and transform instead of multiple SOPs.
I know how that can work with the Copy to points SOP, but was hoping to be able to just use the simple Copy and transform instead of multiple SOPs.
Edited by Lyubomir Popov - 2022年1月3日 09:34:56
Technical Discussion » Copy transform SOP vary scale per copy (alternative to $CY?)
- Lyubomir Popov
- 29 posts
- Offline
Hi, what's the recommended way to access the current copy index in the Copy and transform SOP?
In the old copy stamp SOP $CY gives you the ability to modify based on the current copy indes, but can't figure out a simple way to do this with the Copy transform SOP. The only thing I can think of is adding three points, setting the pscale attribute on those to the values I want, then using foreach as in the foreach copy stamping [www.sidefx.com] tutorial, but this seems a lot of unnecessary work.
Is there a simpler way?
In the old copy stamp SOP $CY gives you the ability to modify based on the current copy indes, but can't figure out a simple way to do this with the Copy transform SOP. The only thing I can think of is adding three points, setting the pscale attribute on those to the values I want, then using foreach as in the foreach copy stamping [www.sidefx.com] tutorial, but this seems a lot of unnecessary work.
Is there a simpler way?
Edited by Lyubomir Popov - 2022年1月3日 08:52:47
Solaris and Karma » Is it possible to import Material X presets?
- Lyubomir Popov
- 29 posts
- Offline
Solaris and Karma » Is it possible to import Material X presets?
- Lyubomir Popov
- 29 posts
- Offline
Hi, daft question but are there any material x presets available in H19, similar to the ones found on e.g. the principal shader? Couldn't find any when I click the cog on a mtlxstandard_surface.
I can see some examples in the official materialx repo on github, is there a way to import those into houdini?https://github.com/materialx/MaterialX/tree/main/resources/Materials/Examples/StandardSurface [github.com]
I can see some examples in the official materialx repo on github, is there a way to import those into houdini?https://github.com/materialx/MaterialX/tree/main/resources/Materials/Examples/StandardSurface [github.com]
Edited by Lyubomir Popov - 2021年12月5日 06:26:23
Technical Discussion » Connecting disconnected points on a mesh without duplicates
- Lyubomir Popov
- 29 posts
- Offline
I'm trying to "partition" a mesh so that the findshortestpath sop runs over a portion of the mesh's points at a time.
In the partitioning process, some of the points of the mesh become disconnected, and I can't find a clean way to reconnect them. I tried connectadjacentpieces, but:
- when used with connectino type: adjacent points, it almost doubles the number of primitives, instead of only connecting the points that are missing (in the following image, I'd expect to see the just one added polyline)
- when used with connectino type: adjacent pieces from points, it doesn't generate any lines - I'm probably not creating the name attribute correctly...
Is the connectadjacentpieces sop the correct tool for this? Or is there a better way?
In the partitioning process, some of the points of the mesh become disconnected, and I can't find a clean way to reconnect them. I tried connectadjacentpieces, but:
- when used with connectino type: adjacent points, it almost doubles the number of primitives, instead of only connecting the points that are missing (in the following image, I'd expect to see the just one added polyline)
- when used with connectino type: adjacent pieces from points, it doesn't generate any lines - I'm probably not creating the name attribute correctly...
Is the connectadjacentpieces sop the correct tool for this? Or is there a better way?
Edited by Lyubomir Popov - 2021年1月24日 11:43:49
Technical Discussion » Skeleton curve implementation based on VDB medial axis
- Lyubomir Popov
- 29 posts
- Offline
Technical Discussion » H18 what's new: "Tool to compute median curves from meshes"
- Lyubomir Popov
- 29 posts
- Offline
Technical Discussion » H18 what's new: "Tool to compute median curves from meshes"
- Lyubomir Popov
- 29 posts
- Offline
Hi, I spotted somethnig called “Tool to compute median curves from meshes” at the end of the What's new in Houdini 18 video [www.sidefx.com] , but I can't find any information on where to find it.
Is it a sop? Is it experimental, do you need to enable anything to get it to appear?
Is it a sop? Is it experimental, do you need to enable anything to get it to appear?
Technical Discussion » Skeleton curve implementation based on VDB medial axis
- Lyubomir Popov
- 29 posts
- Offline
rpopovici This is incredibly useful, thank you for sharing and apologies for jumping into this not so recent thread.
lkruellkruel, when you say merge, does that mean that this (or parts of it) will make its way into houdini?
Thanks! I'll take a look at merging your newest changes in as well!
Technical Discussion » Presets in OTLs
- Lyubomir Popov
- 29 posts
- Offline
Thanks animatrix3d, embedding presets in an asset works fine, no issues there. But let's say I accidentally recorded a transform along the Z axis into a preset (Regardless of whether that preset is in the $HIP/presets folder, or added as an extra file to the hda).
What is the recommended way to edit individual values inside the Presets.idx file? In other words, If I want to change the translate vector in Presets.idx, which looks like so:
In simple .idx files, changing -0.07 to say -0.075 works fine. But in a larger preset file, changing the number of bytes per value corrupts the file and houdini doesn't recognise it. I'll try to narrow it down and upload an example that shows how an idx file that is failing as described.
Either way, I'm curious how do other people edit existing presets? Text editor / hex editor, or is there a better way to do it through the houdini interface.
What is the recommended way to edit individual values inside the Presets.idx file? In other words, If I want to change the translate vector in Presets.idx, which looks like so:
t [ 0 locks=0 ] ( 0 0 -0.07 )
In simple .idx files, changing -0.07 to say -0.075 works fine. But in a larger preset file, changing the number of bytes per value corrupts the file and houdini doesn't recognise it. I'll try to narrow it down and upload an example that shows how an idx file that is failing as described.
Either way, I'm curious how do other people edit existing presets? Text editor / hex editor, or is there a better way to do it through the houdini interface.
Edited by Lyubomir Popov - 2018年7月15日 14:36:44
Technical Discussion » Presets in OTLs
- Lyubomir Popov
- 29 posts
- Offline
Apologies for digging out this really old thread, but I've been trying to do exactly this:
What is the best way to do that? I've only managed to do it with a hex editor, but that allows me to only swap bites - if I want to change a value that is one bite say 0 to something with more bites, for example 0.5, then it stops working.
Is there a more sane way to deal with presets?
mtucker
or editing the presets in that external file
What is the best way to do that? I've only managed to do it with a hex editor, but that allows me to only swap bites - if I want to change a value that is one bite say 0 to something with more bites, for example 0.5, then it stops working.
Is there a more sane way to deal with presets?
Edited by Lyubomir Popov - 2018年7月15日 10:04:28
Technical Discussion » Expression to check whether input contains a specific volume?
- Lyubomir Popov
- 29 posts
- Offline
Technical Discussion » Expression to check whether input contains a specific volume?
- Lyubomir Popov
- 29 posts
- Offline
Hi, is there an expression that tests whether a volume exists? hasprim sounds like it does that but it requires a group, and the third parameter is a prim index, and I'd like to check by name.
To give some context, I'm trying to determine whether the node wired into an input on my asset contains a volume, and use a switch to either pass that volume directly to a volume wrangle, or convert it to a volume and then pass that into the volume wrangle.
To give some context, I'm trying to determine whether the node wired into an input on my asset contains a volume, and use a switch to either pass that volume directly to a volume wrangle, or convert it to a volume and then pass that into the volume wrangle.
Technical Discussion » Attribute wrangle significantly slower than the old point wrangle?
- Lyubomir Popov
- 29 posts
- Offline
UPDATE: Just managed to get Run Over Numbers to work, and it is massively faster and more controllable! Thank you for the suggestion.
I've linked the “Number count” to the number of points I have, and set “Thread Job Size” to number of points / available threads(8). To make sure the comparison isn't affected by the wrangles competing for threads, I run each on it's own.
Results with 2000 points:
Attrib wrangle run over number: 0.825s
Old point wrangle: 2.064s
Attrib wrangle run over points: 3.851s
Just one more question - you mentioned holes in the point list left by the old scatter sop, how can I tell there are holes in the point list?
I've linked the “Number count” to the number of points I have, and set “Thread Job Size” to number of points / available threads(8). To make sure the comparison isn't affected by the wrangles competing for threads, I run each on it's own.
Results with 2000 points:
Attrib wrangle run over number: 0.825s
Old point wrangle: 2.064s
Attrib wrangle run over points: 3.851s
Just one more question - you mentioned holes in the point list left by the old scatter sop, how can I tell there are holes in the point list?
Edited by Lyubomir Popov - 2017年9月6日 04:13:21
Technical Discussion » Attribute wrangle significantly slower than the old point wrangle?
- Lyubomir Popov
- 29 posts
- Offline
Thanks for the detailed reply Jeff, I'm trying to understand all the information
Your code runs faster in both types of wrangles, so I re-run the test with your code only.
Depending on the number of points, I get:
1,500pts - equal performance between old and new wrangles.
2,000pts - old wrangle 2x faster
5,000pts - old wrangle 4x times faster (!)
10,000pts - same speed
So the new wrangle seems very sensitive to the number of points it is working on.
To further isolate the issue, I've replaced the scatter with a simple arrangement of the points done in another wrangle, followed by a sort. I'm eager to try the “Run Over Numbers” mode, but couldn't find an example of how to bind attributes in that mode.
I'm attaching the updated file and a couple of screenshots.
P.S. This example might seem a bit contrived, but it is a simple way to illustrate the issue I'm having as part of a bigger flocking sim where I set attributes on points based on those of their neighbours.
Your code runs faster in both types of wrangles, so I re-run the test with your code only.
Depending on the number of points, I get:
1,500pts - equal performance between old and new wrangles.
2,000pts - old wrangle 2x faster
5,000pts - old wrangle 4x times faster (!)
10,000pts - same speed
So the new wrangle seems very sensitive to the number of points it is working on.
To further isolate the issue, I've replaced the scatter with a simple arrangement of the points done in another wrangle, followed by a sort. I'm eager to try the “Run Over Numbers” mode, but couldn't find an example of how to bind attributes in that mode.
I'm attaching the updated file and a couple of screenshots.
P.S. This example might seem a bit contrived, but it is a simple way to illustrate the issue I'm having as part of a bigger flocking sim where I set attributes on points based on those of their neighbours.
Edited by Lyubomir Popov - 2017年9月5日 19:33:36
Technical Discussion » Attribute wrangle significantly slower than the old point wrangle?
- Lyubomir Popov
- 29 posts
- Offline
Thanks aRtye, I've submitted a bug report, and linked back to this post so they can see everyone's results.
-
- Quick Links