I think i know very well what you mean.
I noticed that long time ago when messing with the pre-release H8.
I am pretty sure i reported it to one of the developers.
In fact the problem is not only with the wire solver, but in sop too - there are cases where the normals flip unpredictably.
Never checked again if it was fixed.
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Houdini Lounge » Hair flipping
- peship
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Houdini Lounge » ramp VOP
- peship
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Usually i create a rampCOP, then assign attribute values read from it according to point's UV coordinates. Then pipe this information in VEX/VOPS.
Or maybe you have something else in mind.
But yeah, ramp function/VOP will be nice.
Or maybe you have something else in mind.
But yeah, ramp function/VOP will be nice.
Technical Discussion » a weird RBD problem
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Thanks.
I left the static solver in the scene, because it is from a more complex setup where it's needed.
I am wondering, is that some sort of bug, or the order of the nodes in this case matters ( opposite to what the help claims ) ?
I clearly see now why some of my previous tests didn't work. They were little chaotic and i didn't notice the pattern that if i have a static solver somewhere at the end of the networks the things get funky.
Once again - thanks for the feedback.
I left the static solver in the scene, because it is from a more complex setup where it's needed.
I am wondering, is that some sort of bug, or the order of the nodes in this case matters ( opposite to what the help claims ) ?
I clearly see now why some of my previous tests didn't work. They were little chaotic and i didn't notice the pattern that if i have a static solver somewhere at the end of the networks the things get funky.
Once again - thanks for the feedback.
Technical Discussion » a weird RBD problem
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I accidentally found something strange about RBDs and wonder if somebody here can take a look and try to make the simulation in the attached scene to somehow work. I am running out of ideas how to stabilize it.
The point is not to use constraints, but to rely on rbd collisions only.
Feel free to apply any changes to the shape and topology of the objects.
Just keep the “swing” effect.
The sim is pretty light.
… and breaks after the first 10-20 frames.
I did and few more tests ( different scenarios than this one ) with concave objects and got some mixed results.
The point is not to use constraints, but to rely on rbd collisions only.
Feel free to apply any changes to the shape and topology of the objects.
Just keep the “swing” effect.
The sim is pretty light.
… and breaks after the first 10-20 frames.
I did and few more tests ( different scenarios than this one ) with concave objects and got some mixed results.
Houdini Lounge » HELP!!! Maya user switching to Houdini
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cluster = transform / softTransform ( to get the pointWeights going, take a look at attribCreate and paint SOP and to use the point attribs data along with the softTransformSOP look at the “point” expression command, in general there are many ways of doing this, but this is the closest one to what you are used in Maya )
freezeTransform = the very top UI element of every objectOP, it's called “Pre-Transform”, pay attention and to the other element next to it “Keep position when parenting”, luckilly this one is not that destructive as the freezeTransform thing in Maya.
goalPP - nope, no dynamic goals for you in Houdini, you can cheat to some point with pointSOPs, expressions or chops tho.
particleID = that's the ID attribute which comes by default with every particle ( for more info - RMB over any OP in Houdini - spreadsheet ). You will find the expressions quite dissapointing, but stay tuned, the upcoming version comes with python stuff, so in most cases it will get much better. Also, some expression commands are really great geometry iterators. For this kind of stuff in Maya i am forced to do API exercises to keep some reasonable performance :?
snapping - ctrl+j and ctrl+shift+j
blendshape snapshot - what you mean ?
constraints: *origin expressions + blendOP can do point orient scale constraining, blendOP to get the transformation in local space, then *origin expressions to pull them in world space so that data can be usefull. Every objectOP has built in aim constraining abilities to some level.
polyAverage = smoothSOP
Have fun.
freezeTransform = the very top UI element of every objectOP, it's called “Pre-Transform”, pay attention and to the other element next to it “Keep position when parenting”, luckilly this one is not that destructive as the freezeTransform thing in Maya.
goalPP - nope, no dynamic goals for you in Houdini, you can cheat to some point with pointSOPs, expressions or chops tho.
particleID = that's the ID attribute which comes by default with every particle ( for more info - RMB over any OP in Houdini - spreadsheet ). You will find the expressions quite dissapointing, but stay tuned, the upcoming version comes with python stuff, so in most cases it will get much better. Also, some expression commands are really great geometry iterators. For this kind of stuff in Maya i am forced to do API exercises to keep some reasonable performance :?
snapping - ctrl+j and ctrl+shift+j
blendshape snapshot - what you mean ?
constraints: *origin expressions + blendOP can do point orient scale constraining, blendOP to get the transformation in local space, then *origin expressions to pull them in world space so that data can be usefull. Every objectOP has built in aim constraining abilities to some level.
polyAverage = smoothSOP
Have fun.
Houdini Lounge » OSX the most poweful OS in the world...
- peship
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Technical Discussion » Fluid Type Motion from Maya to Houdini!
- peship
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just use the fluidContainer as force field.
in fact, if the velocity method is set to dynamic/static grid, the fluidContainer acts as vector field for the rest of the dynamic elements in the scene ( if connected to it ).
There is and another way to export fluid motion:
create a point for each voxel cell, let the point read the properties of it's related voxel ( velocity, color, temperature, etc ), with a simple expressions or collect the data from all the points and dump it in a .clip format.
Build the same points in Houdini ( box or plane with the right amount of divisions ), then pipe the custom data exported from Maya to these points via CHOPs ) In this way you are basically recreating the fluids vector field in Houdini. The last step is attribute transfer the vector fields data to your particles.
This is very usefull approach, because the amount of IO data is very compact and most parts rely on Maya/Houdini ( faster and more reliable than custom coding ).
in fact, if the velocity method is set to dynamic/static grid, the fluidContainer acts as vector field for the rest of the dynamic elements in the scene ( if connected to it ).
There is and another way to export fluid motion:
create a point for each voxel cell, let the point read the properties of it's related voxel ( velocity, color, temperature, etc ), with a simple expressions or collect the data from all the points and dump it in a .clip format.
Build the same points in Houdini ( box or plane with the right amount of divisions ), then pipe the custom data exported from Maya to these points via CHOPs ) In this way you are basically recreating the fluids vector field in Houdini. The last step is attribute transfer the vector fields data to your particles.
This is very usefull approach, because the amount of IO data is very compact and most parts rely on Maya/Houdini ( faster and more reliable than custom coding ).
Technical Discussion » Fluid Type Motion from Maya to Houdini!
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sure,
you have two options:
The first one is to export consistent point count from Maya to Houdini.
It requires little more work in Maya and in general is slower, but the exported data is mutch more usable later in Houdini.
open this file in Maya ( you will need 7.0 ): http://petershipkov.com/temp/mayaToHoudini_consistentPointCount.ma [petershipkov.com]
load the objExport plug-in, select the “extrude” node ( look in Outliner ) and then execute the next script in the scriptEditor:
http://petershipkov.com/temp/mayaToHoudini.mel [petershipkov.com]
note: in most cases you will edit the paths to where you want Maya to spit out the file sequence.
launch Houdini and open this scene: http://petershipkov.com/temp/mayaToHoudini.hipnc [petershipkov.com]
point the fileSOP to where you saved the stuff from Maya.
Here you can check the results:
http://petershipkov.com/temp/inMaya.mov [petershipkov.com]
http://petershipkov.com/temp/inHoudini.mov [petershipkov.com]
————————
The second option is to export inconsistend point count to Houdini, then you can make the process mutch easier ( and less usable later ). Check this file - all the geometry emission is handled by Maya ( which is faster and easier to set-up ):
http://petershipkov.com/temp/mayaToHoudini_inconsistentPointCount.ma [petershipkov.com]
again, select the “extrude” node and execute the same http://petershipkov.com/temp/mayaToHoudini.mel [petershipkov.com] script
done
The process can be fully automated. At least i did it in my previous studio.
you have two options:
The first one is to export consistent point count from Maya to Houdini.
It requires little more work in Maya and in general is slower, but the exported data is mutch more usable later in Houdini.
open this file in Maya ( you will need 7.0 ): http://petershipkov.com/temp/mayaToHoudini_consistentPointCount.ma [petershipkov.com]
load the objExport plug-in, select the “extrude” node ( look in Outliner ) and then execute the next script in the scriptEditor:
http://petershipkov.com/temp/mayaToHoudini.mel [petershipkov.com]
note: in most cases you will edit the paths to where you want Maya to spit out the file sequence.
launch Houdini and open this scene: http://petershipkov.com/temp/mayaToHoudini.hipnc [petershipkov.com]
point the fileSOP to where you saved the stuff from Maya.
Here you can check the results:
http://petershipkov.com/temp/inMaya.mov [petershipkov.com]
http://petershipkov.com/temp/inHoudini.mov [petershipkov.com]
————————
The second option is to export inconsistend point count to Houdini, then you can make the process mutch easier ( and less usable later ). Check this file - all the geometry emission is handled by Maya ( which is faster and easier to set-up ):
http://petershipkov.com/temp/mayaToHoudini_inconsistentPointCount.ma [petershipkov.com]
again, select the “extrude” node and execute the same http://petershipkov.com/temp/mayaToHoudini.mel [petershipkov.com] script
done
The process can be fully automated. At least i did it in my previous studio.
Technical Discussion » Chainmail in DOPs
- peship
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Have you tried to constrain the rings ?
No ring-to-ring collisions, only constraints - the overall performace should be mutch better.
Or you want to see how far you can push the RBD solver maybe ?
No ring-to-ring collisions, only constraints - the overall performace should be mutch better.
Or you want to see how far you can push the RBD solver maybe ?
Technical Discussion » Fluid Type Motion from Maya to Houdini!
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Are you sure you are using padzero expression inside your fileSOP ?
I am asking because i know that it works for sure.
About the second approatch - i am not talking you about animCurves - i am talking you about nurbsCurve primitive. The regular way to “emit geometry” along with particles.
I am asking because i know that it works for sure.
About the second approatch - i am not talking you about animCurves - i am talking you about nurbsCurve primitive. The regular way to “emit geometry” along with particles.
Technical Discussion » Fluid Type Motion from Maya to Houdini!
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You have two options:
convertFluidsToPoly command, then bake the generated polySurface frame by frame in OBJ, load it in Houdini.
Or - use the fluids as particleFields, then use a softbody or simple expression to attatch curve to your particles, then extrude the curve along Y axis ( the offset must be some big value - you need to make sure that all points created by the extrusion are far away from the original particles ). Export the generated polySurface in OBJ's.
Then load it in Houdini and apply a deleteSOP ( boundingBox option ) and position it so it deletes the set of points generated after the extrusion of the curve in Maya - in this way you will have your maya particles representing the fluid sim in Houdini.
Or write a script storing Maya points in .geo format - i wrote one simple .geo exporter long time ago, but dont use it anymore - the second approatch works really well for me.
convertFluidsToPoly command, then bake the generated polySurface frame by frame in OBJ, load it in Houdini.
Or - use the fluids as particleFields, then use a softbody or simple expression to attatch curve to your particles, then extrude the curve along Y axis ( the offset must be some big value - you need to make sure that all points created by the extrusion are far away from the original particles ). Export the generated polySurface in OBJ's.
Then load it in Houdini and apply a deleteSOP ( boundingBox option ) and position it so it deletes the set of points generated after the extrusion of the curve in Maya - in this way you will have your maya particles representing the fluid sim in Houdini.
Or write a script storing Maya points in .geo format - i wrote one simple .geo exporter long time ago, but dont use it anymore - the second approatch works really well for me.
Technical Discussion » particles killing houdini 64
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Technical Discussion » "Insufficient Memory" error
- peship
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For now i'm locked on 32 bit hardware ( both at studio and home ), cant comment on 64 bit distros at all.
Technical Discussion » "Insufficient Memory" error
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Yes, that's right, i have only 2 gigs of RAM at home.
As you read in the article you linked to, from your previous post, there is a flag needed to let the software be a large address aware. If the application is compiled this way, then you only need to tweak the boot.ini thing of Windows and you are ready to go.
If the software is not compiled this way, then it doesn't matter how many flags you will put in boot.ini.
This exactly was the case with Maya.
All the versions prior Maya6 for win32, just die at the moment they reach 1.5 gigs of RAM.
Maya6 was compiled with the large address option included and now it just works. I tried it again ( few minutes ago ) and it still works - stopped the experiment at fully occupied 2 gigs of RAM + filled-up 2 gigs of virutal memory in addition.
If you try the same with Maya5, for example, it will die on 1.3-1.5 gigs of RAM without even touching the virtual memory.
But, wait. I cant reproduce the same with my XP and Houdini8 anymore.
H dies on 1.5 gigs.
Now that's strange.
As you read in the article you linked to, from your previous post, there is a flag needed to let the software be a large address aware. If the application is compiled this way, then you only need to tweak the boot.ini thing of Windows and you are ready to go.
If the software is not compiled this way, then it doesn't matter how many flags you will put in boot.ini.
This exactly was the case with Maya.
All the versions prior Maya6 for win32, just die at the moment they reach 1.5 gigs of RAM.
Maya6 was compiled with the large address option included and now it just works. I tried it again ( few minutes ago ) and it still works - stopped the experiment at fully occupied 2 gigs of RAM + filled-up 2 gigs of virutal memory in addition.
If you try the same with Maya5, for example, it will die on 1.3-1.5 gigs of RAM without even touching the virtual memory.
But, wait. I cant reproduce the same with my XP and Houdini8 anymore.
H dies on 1.5 gigs.
Now that's strange.
Technical Discussion » "Insufficient Memory" error
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It does work.
The last time i tried it, i created 16 000 000 real polys in Maya.
About 25 000 000 real polys in XSI ( XSI has better memory efficiency than Maya ).
And i believe 12 000 000 ( or maybe 18 000 000 ) in Houdini.
Cant remember the exact numbers anymore.
I have only 2 Gigs of RAM in my home PC and i'm using the free versions of the applications - maybe the full versions require little more RAM.
I dont think that a 32 bit compiled programs can allocate more than 4 gigs or RAM, not an expert in this area, maybe somebody else can bring some light here. But i think that if you have available 64 gigs of RAM you can open multiple sessions of Houdini, Maya, XXX, etc without killing your PC ( maybe not ).
What i noticed is that at the moment Houdini reaches the limits of the phisical ram, the application immediatelly crashes.
Maya under Windows continutes dumping stuff in the virtual memory.
Maya under Linux reports something like “memory excetion thrown” and refuses to execute the operation ( adding more polys to the scene ), but the application is still alive and you can save your butt saving the scene or even continue your work.
XSI under Windows just continues dumping stuff in the virtual memory. What is really good about XSI (5+) is that you can actually render whatever you have in the scene - if you can see it in the viewport - you can render it. Maya and Houdini just cant do that.
After some point all apps i tried became useless - waiting too mutch for the next iteration of copy/paste polygons
Never reached the limits of the virtual memory. Qurious to see what happens then. Maybe one day will give it a try
Sounds little nerdish, brute force entertainment, but it was interesting to see how far i can go with the available software these days.
The last time i tried it, i created 16 000 000 real polys in Maya.
About 25 000 000 real polys in XSI ( XSI has better memory efficiency than Maya ).
And i believe 12 000 000 ( or maybe 18 000 000 ) in Houdini.
Cant remember the exact numbers anymore.
I have only 2 Gigs of RAM in my home PC and i'm using the free versions of the applications - maybe the full versions require little more RAM.
I dont think that a 32 bit compiled programs can allocate more than 4 gigs or RAM, not an expert in this area, maybe somebody else can bring some light here. But i think that if you have available 64 gigs of RAM you can open multiple sessions of Houdini, Maya, XXX, etc without killing your PC ( maybe not ).
What i noticed is that at the moment Houdini reaches the limits of the phisical ram, the application immediatelly crashes.
Maya under Windows continutes dumping stuff in the virtual memory.
Maya under Linux reports something like “memory excetion thrown” and refuses to execute the operation ( adding more polys to the scene ), but the application is still alive and you can save your butt saving the scene or even continue your work.
XSI under Windows just continues dumping stuff in the virtual memory. What is really good about XSI (5+) is that you can actually render whatever you have in the scene - if you can see it in the viewport - you can render it. Maya and Houdini just cant do that.
After some point all apps i tried became useless - waiting too mutch for the next iteration of copy/paste polygons
Never reached the limits of the virtual memory. Qurious to see what happens then. Maybe one day will give it a try
Sounds little nerdish, brute force entertainment, but it was interesting to see how far i can go with the available software these days.
Technical Discussion » "Insufficient Memory" error
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few notes based on my personal experience …
windows 2000 is hopeless
in winXP you need to add /3Gb ( or /4GB ) and /PAE flag in the boot.ini file - the /PAE thing activates the 64 bit memory controler ( turned off by default ) - in this way you can use up to 64 Gigs of ram with 32 bit WindowsOS
winServer2003 - this is an amazing OS, no word - rock solid memory management, better than any windows/linux i have ever tried
Linux32 - the biggest difference from Windows ( after tweaking it's boot.ini ) is the performance of the virtual memory. Recovering back to operational state from a heavy memory push is just faster here.
never had chance to play with OSX and UNIX, but will … one day.
windows 2000 is hopeless
in winXP you need to add /3Gb ( or /4GB ) and /PAE flag in the boot.ini file - the /PAE thing activates the 64 bit memory controler ( turned off by default ) - in this way you can use up to 64 Gigs of ram with 32 bit WindowsOS
winServer2003 - this is an amazing OS, no word - rock solid memory management, better than any windows/linux i have ever tried
Linux32 - the biggest difference from Windows ( after tweaking it's boot.ini ) is the performance of the virtual memory. Recovering back to operational state from a heavy memory push is just faster here.
never had chance to play with OSX and UNIX, but will … one day.
Technical Discussion » $TX value referencing a different TX value from past frame
- peship
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Yesterday i dealth with very similar problem, and after struggling for a while with the geometry CHOP i talked with somebody at SESI and it appears that there is a refreshing problem with it - be aware.
All the time while working on that task i tought how good would be if the time in Houdini was not global, but like in Maya, everything can live in it's local time - each one ( the times ) defined by it's timeNode. Extracting dependencies like the one, Jim Ellis talked about, is not even considered as a task.
RFE - local time(s).
All the time while working on that task i tought how good would be if the time in Houdini was not global, but like in Maya, everything can live in it's local time - each one ( the times ) defined by it's timeNode. Extracting dependencies like the one, Jim Ellis talked about, is not even considered as a task.
RFE - local time(s).
Technical Discussion » Maya Channels to Houdini
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for proper Maya to Houdini camera matching:
in Maya:
set horisontalAperture = verticalAperture
in Houdini:
focalLength = focalLength_Maya;
aperture = horisontalApture_Maya * 25.4;
in Maya:
set horisontalAperture = verticalAperture
in Houdini:
focalLength = focalLength_Maya;
aperture = horisontalApture_Maya * 25.4;
Houdini Lounge » Cloaks
- peship
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Technical Discussion » Did anyone try syflex for Houdini?
- peship
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Syflex for Houdini is pretty mutch “evaluation” version.
No collision primitives, no mimic constraint ( cloth goals ), no syFlesh, no sySkin ( multilayered springs ), etc.
By other hand H Cloth has great potential. And is part of the application.
A very good idea is to spend some time to learn DOP's.
I didn't checked, will be DOP's only for Houdini Master or not ?
No collision primitives, no mimic constraint ( cloth goals ), no syFlesh, no sySkin ( multilayered springs ), etc.
By other hand H Cloth has great potential. And is part of the application.
A very good idea is to spend some time to learn DOP's.
I didn't checked, will be DOP's only for Houdini Master or not ?
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