I am looking for a really simple way to cause the value in my RS_Incandescent shader to randomize in quick intervals, simulating the flickering pattern of a neon bulb. I was looking at some noise functions, but I don't see a way to control them to make them do what I want. Also I'm still kinda green in VEX.
Any ideas are appreciated!
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Technical Discussion » Simulating neon bulb flicker with VEX
- fabiobasile
- 28 posts
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Technical Discussion » Caching dynamics in Houdini Console produces HUGE files
- fabiobasile
- 28 posts
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I am trying to cache a water simulation in the console, because the scene also contains a skinned character that is pretty complex, and requires considerable cooking time, so to save UI overhead i thought of creating an output node that plugs into the dop path for the water sim, which is a simple 300x300 flat tank, and use the render command to run the node in console.
If i cache the water sim from Houdini UI, the cached files are less than 50MB each, but if i try to launch the render command from the console to my dop path, the cached files generated are 450MB each. Any idea what i might be doing wrong?
If i cache the water sim from Houdini UI, the cached files are less than 50MB each, but if i try to launch the render command from the console to my dop path, the cached files generated are 450MB each. Any idea what i might be doing wrong?
Technical Discussion » treadmarks with BlendShapes and redshift materialBlender
- fabiobasile
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So in the end i was able to simply keyframe a ramp in the RS material blender blend color channel to more or less match the trajectory of the tracks, which feels a little convoluted, and probably not very practical for more complex projects. Any way to simplify this workflow so i don't have to do a lot of things separately?
Technical Discussion » treadmarks with BlendShapes and redshift materialBlender
- fabiobasile
- 28 posts
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I guess i solved half of the problem by creating a group encompassing all polygons of my terrain, and turning on the option Keep in boundary Regions. I then specified a sphere boundary, resized its diameter to the width of the terrain, and then moved it back till its edge matched the position of my character. Finally, i keyframed the boundary translate position to match the character, although now that i think about it, i could have simply referenced it and adjust it with negative values…
At any rate, i am now still faced with the relatively simpler problem of doing the same with my two redshift blended shaders…
At any rate, i am now still faced with the relatively simpler problem of doing the same with my two redshift blended shaders…
Technical Discussion » treadmarks with BlendShapes and redshift materialBlender
- fabiobasile
- 28 posts
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I'm looking for a way to simulate tread marks. I currently have two meshes for the terrain which I want to blend, and two materials I want to merge using Redshift materialBlender.
I am looking for the best way to cause the mesh and the materials to blend simultaneously, as the monster's tracks advance on the terrain. Ideally I would like to learn a procedural approach, so that the blending is calculated according to the position of the character on the terrain.
Any help is appreciated!
I am looking for the best way to cause the mesh and the materials to blend simultaneously, as the monster's tracks advance on the terrain. Ideally I would like to learn a procedural approach, so that the blending is calculated according to the position of the character on the terrain.
Any help is appreciated!
Technical Discussion » Improving 8K textures close-up (Redshift)
- fabiobasile
- 28 posts
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Here's a happy update:
According to a response i got in the RS community forums, a working fix is to go into the experimental section of the Redshift ROP, under System, and check “Render In Camera Space”. I have tested it an apparently the issue is gone.
According to a response i got in the RS community forums, a working fix is to go into the experimental section of the Redshift ROP, under System, and check “Render In Camera Space”. I have tested it an apparently the issue is gone.
Technical Discussion » Improving 8K textures close-up (Redshift)
- fabiobasile
- 28 posts
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You may be onto something, and this makes total sense. I suspect that this may very well be a RS issue, as all my textures, no matter what mesh I use, present similar problems.
I have initially created the scene to reflect roughly accurate distances between the Sun, Moon and Earth, as well as their relative size, scaled down to by quite a few decimals to make it manageable, but not so small as to have the moon down to 0.0000~e scale. Still, proportionally, the distance between the sun and earth/moon is about 1 kilometer, and i have placed an RS point light inside the Sun, and have specified only the moon and earth in the list of objects influenced by the light source. I have also a light dome, which does not affect anything, as i have turned it off, and only used it to have a spherical projection of the stars, which I have generated from NASA footage, and down-sampled it to a 2Kx4K.
All meshes are textured using UDIM tiles, however the issue manifested even with regular textures.
I have eliminated all the volumes, dome light, and rendered each mesh individually, and I also tested it with sample objects, and the issue still persists.
I will bring this issue to the attention of the RS community as well, hopefully I'll get to the bottom of it, but thanks for pointing me in a good direction, very much appreciated! :-)
I have initially created the scene to reflect roughly accurate distances between the Sun, Moon and Earth, as well as their relative size, scaled down to by quite a few decimals to make it manageable, but not so small as to have the moon down to 0.0000~e scale. Still, proportionally, the distance between the sun and earth/moon is about 1 kilometer, and i have placed an RS point light inside the Sun, and have specified only the moon and earth in the list of objects influenced by the light source. I have also a light dome, which does not affect anything, as i have turned it off, and only used it to have a spherical projection of the stars, which I have generated from NASA footage, and down-sampled it to a 2Kx4K.
All meshes are textured using UDIM tiles, however the issue manifested even with regular textures.
I have eliminated all the volumes, dome light, and rendered each mesh individually, and I also tested it with sample objects, and the issue still persists.
I will bring this issue to the attention of the RS community as well, hopefully I'll get to the bottom of it, but thanks for pointing me in a good direction, very much appreciated! :-)
Technical Discussion » Improving 8K textures close-up (Redshift)
- fabiobasile
- 28 posts
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I have rendered this simple scene with Redshift, using textures generated by processing 16K and 8K assets from NASA and https://www.solarsystemscope.com/textures/ [www.solarsystemscope.com].
I have attached three sampled screenshots from the resulting 10000x10000 rendering, which looks terrible for some reason. The textures are in PNG format, and I have attached a sample of the flat texture I used for the lunar surface.
Is there a way to improve the definition of the texture, maybe with a filter? Does RS have any specific filter that might help?
I have attached three sampled screenshots from the resulting 10000x10000 rendering, which looks terrible for some reason. The textures are in PNG format, and I have attached a sample of the flat texture I used for the lunar surface.
Is there a way to improve the definition of the texture, maybe with a filter? Does RS have any specific filter that might help?
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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Update: apparently, adding the Vellum IO node will interfere with group-based collisions by wrangle or property expression, at least when collision groups are defined within the same mesh (i.e. the sleeves of a jacket).
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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I haven't tested this on my actual scene, but i did manage to accomplish the same effect on this smaller test scene i reverse engineered from one of the samples.
I have created four groups:
1. left half of torus
2. right half of torus
3. left half of plane
4. right half of plane
Next i have set collision groups for the two halves of the torus, and the plane respectively.
Finally, i have setup collisionignore expression nodes pointing at the name of the groups.
The result is that only one half of the torus, and one half of the plane are affected by collision, leaving the other halves unaffected.
That took me way too long to figure out… lol
I have created four groups:
1. left half of torus
2. right half of torus
3. left half of plane
4. right half of plane
Next i have set collision groups for the two halves of the torus, and the plane respectively.
Finally, i have setup collisionignore expression nodes pointing at the name of the groups.
The result is that only one half of the torus, and one half of the plane are affected by collision, leaving the other halves unaffected.
That took me way too long to figure out… lol
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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Oops, i just added a second attribute to the node, so the same attribute expression has both the collisiongroup and collisionignore, but still no dice… should i create separate attribute expression nodes for each collision attribute?
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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Thanks, i have spent a bit of time going through the example here: https://www.sidefx.com/docs/houdini/examples/nodes/sop/vellumsolver/CollisionIgnore.html [www.sidefx.com]
and i have replaced the wrangles with attribute expressions like in the examples. I have specified the name of the nodes of the collision groups i want to use in the form of a string in VEX expression, and typed the property collisiongroup in the name field.
For some reason it still has no effect as all, as if the attribute expression node isn't even there. I'm not sure what i am missing…
and i have replaced the wrangles with attribute expressions like in the examples. I have specified the name of the nodes of the collision groups i want to use in the form of a string in VEX expression, and typed the property collisiongroup in the name field.
For some reason it still has no effect as all, as if the attribute expression node isn't even there. I'm not sure what i am missing…
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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Being very new to VEX and how to use property wrangles, I am not quite sure. I assumed that the property collisiongroup and collisionignore with “pants_leg_right” (the name of the group to which it belongs), would call that group and set it to ignore collision with leg_left, but it's just me kinda hitting levers and pushing buttons since i couldn't find a lot of sample code to play with that would apply to this situation.
So let's say I have these groups of primitive setup, how would i go about setting them up to ignore collision using a wrangle?
So let's say I have these groups of primitive setup, how would i go about setting them up to ignore collision using a wrangle?
Technical Discussion » Remove collision property on just part of a mesh [vellum]
- fabiobasile
- 28 posts
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Sorry for reopening this thread, but I am having a very similar issue.
In my case, I have an alembic cached character, with separate vellum clothing.
In order to govern the way that each clothing piece responds to vellum collision, I have created separate vellum attachment nodes with different properties, which works ALMOST perfectly. The only problem I am having is that at some point during the animation, the mesh of the feet of the character almost interpenetrate, causing the clothing of the pants to get caught.
I figured I could resolve the issue by creating groups of points for each character's leg, and each of the pants leg as well, and then use a property wrangle to ignore collision between the right character leg and the left character pants, and viceversa.
This seems to have absolutely no effect, and I have tried everything, even setting multiple wrangles for each property, as per screenshot.
The scene is way too big to upload together with the alembic meshes, so I hope the screenshot is sufficient at least for a rough determination of what I might be doing wrong. Any help is appreciated!
- Fabio
In my case, I have an alembic cached character, with separate vellum clothing.
In order to govern the way that each clothing piece responds to vellum collision, I have created separate vellum attachment nodes with different properties, which works ALMOST perfectly. The only problem I am having is that at some point during the animation, the mesh of the feet of the character almost interpenetrate, causing the clothing of the pants to get caught.
I figured I could resolve the issue by creating groups of points for each character's leg, and each of the pants leg as well, and then use a property wrangle to ignore collision between the right character leg and the left character pants, and viceversa.
This seems to have absolutely no effect, and I have tried everything, even setting multiple wrangles for each property, as per screenshot.
The scene is way too big to upload together with the alembic meshes, so I hope the screenshot is sufficient at least for a rough determination of what I might be doing wrong. Any help is appreciated!
- Fabio
Edited by fabiobasile - Sept. 12, 2020 22:56:56
Technical Discussion » What do you use for previs?
- fabiobasile
- 28 posts
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I've recently began experimenting with Wren to do previs, and i notice it's pretty slow with complex scenes.
What do you guys use to quickly preview a scene?
Ideally it would be nice if i could get as quick a draw as the time it takes to compute dynamics.
What do you guys use to quickly preview a scene?
Ideally it would be nice if i could get as quick a draw as the time it takes to compute dynamics.
Technical Discussion » White water strange clustering
- fabiobasile
- 28 posts
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Not sure what i'm doing wrong here, after adding the beach waves simulation from the toolbar and setting up my mesh as collider, i noticed that little or no whitewater foam was showing up. I tried increasing the density of the particles, and now i'm getting little cubic patches packed with hundred of particles all clumped up together, floating far away from each other…
I'm still learning about FLIP simulations, so it's entirely possible i must have fudged something up… any help is appreciated!
I'm still learning about FLIP simulations, so it's entirely possible i must have fudged something up… any help is appreciated!
Technical Discussion » Noob question: Manipulating Alembic Frame channel
- fabiobasile
- 28 posts
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Probably not as elegant a solution as i was hoping, i ultimately resorted to dropping a re-time node, and keyframing the top start and end frame channels to key in the exact moment i want the animation to occur, and then keyframe the frame rate to control the speed.
It's a bit convoluted and not as straightforward as i was hoping, but it's a means to an end until i learn a bit more about what i can do with VEX.
It's a bit convoluted and not as straightforward as i was hoping, but it's a means to an end until i learn a bit more about what i can do with VEX.
Technical Discussion » Noob question: Manipulating Alembic Frame channel
- fabiobasile
- 28 posts
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Progress!
I was able to run the VEX from your file into my wrangle, and now i'm able to delay or shorten my Alembic by changing the second value of fit01().
Now i guess i have to figure out how to reverse the direction of the frames. I've been theorizing that i could perhaps create an array, and somehow play it in reverse using the reverse function, but since frames are stored as seconds of time, maybe there is another way?
I was able to run the VEX from your file into my wrangle, and now i'm able to delay or shorten my Alembic by changing the second value of fit01().
Now i guess i have to figure out how to reverse the direction of the frames. I've been theorizing that i could perhaps create an array, and somehow play it in reverse using the reverse function, but since frames are stored as seconds of time, maybe there is another way?
Technical Discussion » Noob question: Manipulating Alembic Frame channel
- fabiobasile
- 28 posts
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Update:
Within the wrangle, i clicked on the Bindings tab and then checked “Update normals if displaced”, which got rid of the error altogether. Alas, my alembic umbrella is still completely unresponsive (it works fine when i let it run with $F in the Frame channel)
Within the wrangle, i clicked on the Bindings tab and then checked “Update normals if displaced”, which got rid of the error altogether. Alas, my alembic umbrella is still completely unresponsive (it works fine when i let it run with $F in the Frame channel)
Technical Discussion » Noob question: Manipulating Alembic Frame channel
- fabiobasile
- 28 posts
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So, i've created a primitive wrangle, and pasted in, and now i'm getting these errors. It seems that @elemnum appears to be an undeclared variable:
setprimintrinsic(0, "abcframe", @elemnum, 4, "set");
Error Invalid source /obj/umbrella_export/attribwrangle1/attribvop1 Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Error in VOP 'snippet1'. Warning: Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Error: Vex error: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50) Failed to resolve VEX code op:/obj/umbrella_export/attribwrangle1/attribvop1 Unable to load shader 'op:/obj/umbrella_export/attribwrangle1/attribvop1'. Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Error in VOP 'snippet1'. Warning Errors or warnings encountered during VEX compile: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50). Warning Vex error: /obj/umbrella_export/attribwrangle1/attribvop1/snippet1: Reference to undefined variable: _bound_elemnum (1,37:50) Failed to resolve VEX code op:/obj/umbrella_export/attribwrangle1/attribvop1 Unable to load shader 'op:/obj/umbrella_export/attribwrangle1/attribvop1' Warning Reference to undefined variable: _bound_elemnum (1,27:40)
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