Off the top of my head, here are a few general approaches.
1) Siimulate the particles on reversed animation. Then play render in reverse. This is known as chi-ting.
2) Invisible surface to creep along that follows the shape of the deforming geo.
3) Assign partices goal positions on a surface. Using uv's (or other attributes) you could probably determine the surface point in space. Then you could blend the particle position & velocity in endless amounts of ways towards that goal.
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Technical Discussion » how to make particles fly to moving and deforming boject?
- pinkwerks
- 49 posts
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Houdini Lounge » Maya and Houdini integration? (compositing)
- pinkwerks
- 49 posts
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You always have the option of exporting the fluid surfaces via FBX or similar back to Maya for rendering. Then you shouldn't have any problems with integration.
Indeed an FBX export of the camera from Maya works well to.
Indeed an FBX export of the camera from Maya works well to.
Technical Discussion » kill signals
- pinkwerks
- 49 posts
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Hi I like to kill things on linux gracefully where possible - meaning, if I kill a hung instance of houdini I don't usually do it with -9 cause I'd like to give Houdini a saving throw and prey that it saves a .hip to /tmp.
occasionally I find the houdini interface gets a bit hung up and steals the mouse focus while drawing a menu or something - leaving my machine unable to click on anything but I can move the mouse around.
which makes me wonder - is their a certain kill signal (SIGUSER etc) you can send to houdini that would tell it to redraw the GUI or do a bit of clean up in case it's stuck in some minor loop? if not one for that - is there a list of supported signals in general?
thx.
-p
occasionally I find the houdini interface gets a bit hung up and steals the mouse focus while drawing a menu or something - leaving my machine unable to click on anything but I can move the mouse around.
which makes me wonder - is their a certain kill signal (SIGUSER etc) you can send to houdini that would tell it to redraw the GUI or do a bit of clean up in case it's stuck in some minor loop? if not one for that - is there a list of supported signals in general?
thx.
-p
Technical Discussion » paint brush not working
- pinkwerks
- 49 posts
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Okay, not a bad idea. I'll go ahead slap down another paint node as a work around. Or maybe even go back to a previous version.
What's strange is the paint overlay only shows up on one of the faces in the model but disappears for others. It seems the sop thinks this one face is the only valid face to paint on… oh well thanks for the reply.
What's strange is the paint overlay only shows up on one of the faces in the model but disappears for others. It seems the sop thinks this one face is the only valid face to paint on… oh well thanks for the reply.
Technical Discussion » paint brush not working
- pinkwerks
- 49 posts
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I've been grooming fur on a model for a bit now and for some reason my ‘paint_furlength’ node won't display the brush overlay and let me paint. Well actually, it seems to pop on briefly in certain areas of the geometry then off again. Other paint nodes, before and after in the shop chain display and work fine. I've tried resetting the parameters in the interface, but to no avail. As a last resort I used the gear menu's revert to defaults and the brush comes back, but of course I loose all the paint work I've been doing. Is there some trick to jiggle this node back to a working state without loosing my painted values?
Technical Discussion » textured hair color
- pinkwerks
- 49 posts
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Yes! This is a nice solution. Thank you.
My pesky brain however is still puzzled where the surface color is actually transferred to the hairs in the first place. Any illumination on this would be conceptually helpful. Is this something that happens behind the scenes in the fur SOP? Or perhaps is there a node in the fur network that explicitly gives the hair a default color independent of the textured hair SHOP?
My pesky brain however is still puzzled where the surface color is actually transferred to the hairs in the first place. Any illumination on this would be conceptually helpful. Is this something that happens behind the scenes in the fur SOP? Or perhaps is there a node in the fur network that explicitly gives the hair a default color independent of the textured hair SHOP?
Technical Discussion » textured hair color
- pinkwerks
- 49 posts
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Well, unfortunately I forgot to mention that I'm trying to avoid assigning the material at the OBJ geometry (top) level. Your scene gives the expected result, but it's not a valid solution in my case. I'm reading in some OBJ's from a file SOP and assigning materials at the SOP level. The obj comes in as multiple groups so I'm putting a shader on the eyeballs, skin, etc. Thanks for taking a look - I'm still digging for the answer myself.
Technical Discussion » textured hair color
- pinkwerks
- 49 posts
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I'm using the textured hair material. I'm finding that if I apply a material to my geometry at the SOP level, the textured hair material picks up color from the surface. This is not what I want. I want a material on the ‘skin’, but I only want to use root/tip color in the textured hair material and not have it inherit color from the surface's material.
I'm using hfs9.5.379. I know the docs mention (http://localhost:48628/fur/changingcolor) [localhost] that you need to remove the material to prevent it soaking up the color - but I'd like to use it cause it has most of what I need, and only one property I don't. Is there not a compromise?
Easy enough I thought, I'll just alter the hair SHOP network to not use any of the color attributes from the surface material it's sprouting from. I've tried diving into the SHOP net in the auto generated fur network, but I fail to understand where in the hair SHOP it's picking up the surface's material color. Strangely, unplugging nodes in the SHOP doesn't affect the render. Are SHOPS auto compiled or do I need to flag an update (houdini noob here)? I'm lost, any directions?
I've attached a file, if someone could tell me how to prevent the surface color from bleeding into the hair I'd appreciate it.
I'm using hfs9.5.379. I know the docs mention (http://localhost:48628/fur/changingcolor) [localhost] that you need to remove the material to prevent it soaking up the color - but I'd like to use it cause it has most of what I need, and only one property I don't. Is there not a compromise?
Easy enough I thought, I'll just alter the hair SHOP network to not use any of the color attributes from the surface material it's sprouting from. I've tried diving into the SHOP net in the auto generated fur network, but I fail to understand where in the hair SHOP it's picking up the surface's material color. Strangely, unplugging nodes in the SHOP doesn't affect the render. Are SHOPS auto compiled or do I need to flag an update (houdini noob here)? I'm lost, any directions?
I've attached a file, if someone could tell me how to prevent the surface color from bleeding into the hair I'd appreciate it.
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