Falloff (Control) object

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Hi guys can you help me out?

Is there a way that I can control a specific effect based on a fall off object?
Basically i'm working with this guy who is a long c4d user. He showed me a feature where you can control a bunch of effects or their intensity based on a falloff object. In other word let me examplify…
Imagine i have a bunch of copied boxes in a grid pattern or so. I then apply a transform moving all of them 2 units in the y axis…
What i want is to control the amount of “transform” applied based on the fact if this primitives are inside my fall off object or not…

You can check this example in this image i found in which the falloff object controls the y scale:



I know i can order vertex in x or y, etc but this control volume seems to be a great feature because this can be applied to any effect… Additionaly this system in c4d has like an outter volume for maximum, an inner volume for minnimum and a ramp where you control the falloff. Maybe there's something like it in houdini but I'm not aware of it.
Can you help me?
Thanks.
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One way might be to use a metaball as your “falloff object” and then apply it to your geometry using the magnet sop [sidefx.com] (see the online help for examples). You can set it to set an attribute and then drive your deformation effect using it.
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Heres an example ….

Rob

Attachments:
rse_cube_magnet_spin_attr.hip (87.8 KB)

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This is perfect… But there's just one problem…. For the specif project i'm working in i need the magnet to be cubic, not spherical.. I tried to connect a box to an iso offset or to a vdb volume but neither of this works as a magnet…
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Here's another take on it, with SDFs

Attachments:
ee_falloff_transform.hip (223.4 KB)

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Hi,

I've modified the example before and used the XYZDist in the Attribute VOP to get for each Point of the surface the shortest distance to an Input object, which is a curve in my case. The “Null” is not working for me as Point, so i used a dummycurve which has only one Point (0,0,0).

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rse_cube_attrVOP_scale_168.hipnc (117.6 KB)

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Accordingly let me tell you, you guys, make this the best 3d package community out there, thnaks so much.. I'm really into making a full transition to houdini right now… I really believe that Houdini, with access to all this deep data detail can replace with ease cinema 4d in the motion graphics field.. Maybe not as quick or easy to set up but much, MUCH more powerfull…
Again thank you all for your help..
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Here I am again… -.-' Sorry guys… But learning Houdini on your own is not that easy…

I managed to use the previous solutions with the work i was doing but this challenge comes from the fact that i don't want to use this falloff object with a copy but to animate an operation (in this case the polyreduce percentage)…
I'm posting my scene so you guys can help me. Why does this attribute does not compute the results with this particular field?

I'm trying to integrate houdini in the pipeline but is coming quite painfull when you're asked with results for yesterday (so much for RnD in small studios).. -.-'

Thank you all. Hope you can help me…

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BIGGS_Mesh_Animator.hip (91.7 KB)

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Hi!

The .hip is using some cmivfx assets which are not included, so this is a bit adapted, but should have the important bits. Parameters like the percentage slider want a single constant value, so you can't use a point attribute there. It really just depends on the node whether they accept per-point parameters.

Luckily, Pointreduce can use a “weight” attribute, so you have to name your attribute that.

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biggs_mesh_animator_ee.hip (128.3 KB)

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Hmm. Yeah sory for that but basically you could replace all that for a simple extruded text… The question remains. I've opened your file, but i don't think i'm getting it. Mapping the attribute to the poitn weight makes it slightly transform when the metaball is in the right of it but as long as the point is out of the metaball's range or at the right of it, the mesh remains intact. Hmmm… I'm posting a new non asset dependent scene.
Sorry 4 the inconvenience…

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BIGGS_Mesh_Animator_clean.hip (85.0 KB)

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Ok, I guess I just haven't understood what it is you want to achieve in the end here. Mind explaining it again?
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Ok, so here's the deal. If your polyreduce is at retain 0 per cent you just have a bunch of points, no mesh there.. as you increase you get that “mesh forming from polygon growing” effect. I want to do this but instead of animating all at once i want a based on X axis delay.. Does that make it clearer?
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Also eetu, pls check your pm's, I've sent you a message regarding learning houdini.. Thanks..
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I'm sorry, I still don't get it. Just describe us, without mentioning any nodes or parameters, what kind of an effect you want to achieve. It's quite easy to get caught in trying to do things in one particular way, when it might be wise to try some other approach altogether.

Attached is one try at guessing what you might want to achieve, this time using eroding distance fields..

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biggs_mesh_animator_clean_e.hip (181.2 KB)

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Hmm, indeed maybe i'm not making myself clear… What i want is to make the mesh (in this case, the text) to appear as it's coming from a low poly look, or in other words, i want sort of an expanding number of polygons till it gets fully contructed, or basically, starting from a triangle it goes gainning resolution and becomes the final mesh.. That's kind of what polyreduce SOP does but the thing is that in a mesh with the words “SUPER MARIO” i ante the S to start forming, then slightly after the U, P, E, etc… Is like instead of transforming all at once there's a delay based on the X position of the set of existing meshes (1 per letter, in this case).

All examples I see are kind of the oposite (they deconstruct instead of constructing) and with just one mesh… Here are some of the look i'm after:

http://vimeo.com/73073734 [vimeo.com]
http://vimeo.com/43315740 [vimeo.com]


Thank you so much for the help!
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I did not read the whole thread, but maybe this is what you are looking for…or not.

https://vimeo.com/93915199 [vimeo.com]
Werner Ziemerink
Head of 3D
www.luma.co.za
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hmmm. Kinda is.. It gave me some good ideas… I'll be posting the final result when it's done.. Thank you all…
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