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Scott C. Zupek
10-26-2006, 10:28 PM
Okay added dynamic object wind. I set it to linear direction w/ 50m as the strength. I added an object(Which was a tree created using an lscript). when I am in the FX_Browser it says no dynamics. So naturually when I hit START to calculate and see the effect, nothing is happening. I have ALL GROUPS selected and its the only object in the whole scene. I just to see the limbs move, but will focus on the parts later. Do i need to create a FIXED part before the FX_Generator will effect it?

Thank you:lwicon:

SplineGod
10-26-2006, 11:50 PM
Wind will only effect other items that have dynamics applied to them ie. an object that has cloth dynamics applied to it.

Scott C. Zupek
10-27-2006, 12:11 AM
so do i have to make it a softbody(using soft body dynamix aka soft_Fx)?

SplineGod
10-28-2006, 08:55 PM
Id probably use displacement maps to animate the trees rather then dynamics.

JamesCurtis
10-29-2006, 09:42 AM
Yeah, if you assign a displacement such as fractal noiseto the object with falloff or gradient at the bottom you can do it. I've used the technique quite often for blades of grass and leaves and stuff.

SplineGod
10-29-2006, 09:52 AM
Or use weight maps

Scott C. Zupek
10-30-2006, 11:02 AM
the tree generator creates the weight map with it. i figured if i apply the wind to the softbody, the weightmap would move it all around automatically. what i dont get is how to use motion as a displacement map... maybe i've done it and dont even know i have.... any good turtorial around the net for it?

thank you

SplineGod
10-30-2006, 07:05 PM
You can apply a displacement map which will displace the whole tree. The weight map can be used as the input parameter for a gradient with its blending mode set to alpha so that it will pin the areas that have 100% weight and give greater displacement with areas that have a lesser strength weight.

You can use dynamics. The weight map can be used to Fix geometry. The problem is that when you use a weight map to fix geometry its either fixed or not fixed. It only cares that theres a weight map on not its strength. This means that points with 0% weight and points with 100% get fixed the same.
You can use other weight maps to effect other aspects of the dyanamics such as hold structure, sub structure etc. Theres a lot more work to get this to work right esp if you dont have much experience using clothfx.

Scott C. Zupek
10-30-2006, 10:05 PM
so long story short, figure out displacement maps;) thanks as always larry..
:thumbsup:


You can apply a displacement map which will displace the whole tree. The weight map can be used as the input parameter for a gradient with its blending mode set to alpha so that it will pin the areas that have 100% weight and give greater displacement with areas that have a lesser strength weight.

You can use dynamics. The weight map can be used to Fix geometry. The problem is that when you use a weight map to fix geometry its either fixed or not fixed. It only cares that theres a weight map on not its strength. This means that points with 0% weight and points with 100% get fixed the same.
You can use other weight maps to effect other aspects of the dyanamics such as hold structure, sub structure etc. Theres a lot more work to get this to work right esp if you dont have much experience using clothfx.

bryphi7
10-30-2006, 10:31 PM
The problem is that when you use a weight map to fix geometry its either fixed or not fixed. It only cares that theres a weight map on not its strength. This means that points with 0% weight and points with 100% get fixed the same.

That has gotten on my nerves for a while now... Wish they would make it work as expected. Would be 10X more useful!

SplineGod
10-30-2006, 11:03 PM
You can use weight maps the way you think. Most of the options in the clothfx tab can be controlled using weight maps. Its really pretty powerful since you have use multiple WMs for different things. For example a weight map can be used to control the polygon size to get folds and draping. You can also use this to tighten up areas on a shirt or pants that tend to hang too loosely. WMs can also be used to make differnent areas on the cloth object behave differently as well.
If you notice you can use other VMaps besides WMs to fix or be used for an effect. Pretty much anything you can tag an object with; UVmaps, color maps, parts, surfaces, point groups and so on. :)

bryphi7
10-30-2006, 11:33 PM
how about that!!! You learn something new every day:D. When I first used cloth effects I found out real fast that the fix doesn't support falloff, and I assumed that it didn't work on the other properties either... I was wrong. That is way more useful then I originally thought... Thanks for making me check again:D. I guess I should not assume from now on!!

SplineGod
10-30-2006, 11:42 PM
The nice thing also is that you can use surfaces, weight maps, uvmaps, etc etc etc as ways to select things when using EditFX as well. It opens up a lot more possibilities :)

bryphi7
10-30-2006, 11:49 PM
sure does... I am messing with it now.
You could definitely get some good tree movement with enough tweaking.

Scott C. Zupek
10-31-2006, 08:42 AM
what!? i wanna see. The only way I know of doing things is the **** FX way. I dont know about displacement maps and blah blah blah. I get the idea behind weight maps, but are you manually supposed to "displace" something? for instance, if i wanted to produce a wind look using displacement maps in a tree, would i just go keeping around different shake effects? or is the displacement map supposed to do it over time automatically?

thanks

SplineGod
10-31-2006, 09:27 AM
Displacement maps have long been a part of LW well before *****FX showed up. Its easier to setup, control and predict.

Displacement maps can be done using bitmaps (still or moving images), procedural textures and gradients. The greyscale value of the texture moves vertices.

Displacements can be along an axis, along normals, and along a morph.

Displacing along a morph is particularly good becuase you have more control.

Heres a quick example of animating leaves using a morph:
http://www.3dtrainingonline.com/examples/leaves.mov

Heres another using a procedural texture to displace geometry:
http://www.3dtrainingonline.com/examples/atomic_explosion.mov

LightFreeze
10-31-2006, 10:51 AM
Just to avoid confusion, a weight map value of 0% will not fix, any other value will however

SplineGod
10-31-2006, 10:58 AM
a weight map of any value will fix. Best thing to do is try it. Like I said, ANYTHING you can apply as a tag to an object such as surfaces, part names, vmaps etc can be used to fix. :)

pooby
10-31-2006, 11:21 AM
-this is a method you could use.

Dynamics and metalink. much easier to set up than dynamics on the tree alone, but probably looks better on wider shots with lots of trees rather than just one. (you need to calculate)

I developed this ages ago and never used it properly on anything.

LightFreeze
10-31-2006, 02:03 PM
Just checked again, using 8.5 or 9, a weight value of 0% does not fix

SplineGod
10-31-2006, 04:56 PM
Yup, anything nonzero fixes. :)