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dukestreet
12-05-2003, 03:20 PM
Ok, what I'm trying to do is do a cut away view of a tunnel being dug into rock. The digging is done by an explosive device that shoots repeatedly - that's not the problem.

I'm having an issue trying to model the tunnel as it grows, in this case moving from the top of the screen to the bottom.

Are there any techniques that I could use to make this work smoothly?

Thanks,

D

Chagidiel
12-05-2003, 04:13 PM
I have recently had to use metaballs in a project, so that strikes me as a spontaneous suggestion for you; to use a flat array of metaballs as the rock, and animate a string of metaballs or a metaedge with negative influence setting as the tunnel being dug.

This will however reduce your over all control of the rock-objects appearance, and there are certainly other ideas (will be presented by the good people here I guarantee :) ) and ways to do this. This struck me as a cool idea though... had to throw it in ;)

Good luck

/Erik

dukestreet
12-05-2003, 04:29 PM
That sounds feasible, but again, like you said, it lacks a little of the control I'd need. Also, I'd be concerned that the cutaway wouldn't look that clean.

In a simple test that I used endomorphs - an initial one and a final with the tunel just stretching out between the two for the animation.

It ended up way too regular. However, maybe with the addition of a group of metaballs along with the endomorph I could make the tunnel edges irregular looking as the tunnel moves down through the metaball object.

In the same vein, an irregular model could be just behind the cut away and it would appear as the endomorph moves between positions.

I might have just thought this out myself, with a little nudge from Chagidiel :D

Thanks!

And if anyone has any ideas, I'd love to hear them.

D

3DDave
12-05-2003, 04:53 PM
It's hard to say without a picture of what your trying to do. Is this a 2D or a 3D view?

Anyway, can't you make the tunnel, then fill it up with tunnel objects that you will remove during each blast. This may need compositing to work really well though. Each blast would cover up the object disolve to reveal the tunnel growing.

Steve Warner
12-05-2003, 05:59 PM
Hi Dukestreet,

I'd try using one of the fake boolean plugins in combination with a couple of particle emitters. The fake boolean would work well for carving out the shape of your tunnel. The particle emitters would be good for creating dust and debris from your explosive devices.

Here's a link to a couple of tutorials I did back in July on the use of fake booleans:

http://www.cgtalk.com/showthread.php?s=&threadid=76657

Hope this helps!

Steve

dukestreet
12-05-2003, 07:20 PM
3DDave: That sounds like a good idea as well, but how do I get it to not look like the tunnel has not already been dug up and then refilled with other pieces. Keeping the continuity of the texture is not a problem, but all the little bits would need to look flush with the XSection.

I'll post a pic as soon as I can.

Steve: Thanks for the link to the plugin - but the link for the actual plugin leads to a dead page (in Japanese). Do you have another link for it?

Thanks!

D

LittleFenris
12-05-2003, 07:25 PM
Steve, your tutorials for those boolean plugins are awesome!! Thanks. That technique will come in handy for the short film I am planning out right now. :buttrock:

Steve Warner
12-05-2003, 07:31 PM
Here's a link to the SHIFT Fake Boolean plugin:

http://www.trinitymediainc.com/Downloads/BooleanTexture.zip

On the tutorial link I previously posted, go to the second tutorial. That's the one specific to the SHIFT plugin. I've also got a scene file there for you to help get you started.

Cheers!

Steve

Steve Warner
12-05-2003, 07:32 PM
Originally posted by VWTornado
Steve, your tutorials for those boolean plugins are awesome!!
Thanks! :) I'm glad they were helpful. Please let me know if you need any additional info or support.

Cheers!

Steve

SplineGod
12-05-2003, 08:09 PM
Another method I would try would be to have two endomorphs; a base setting with the tunnel sealed and a second one with the tunnel open and the edges jittered to make it look a little rough.

Then what I would do is use the normal displacement plugin in layout which allows you to activate the morph based on distance to an object via gradients or with another texture. The idea is that you can control the morphing to occur in stages, when and where you want. The dust and debris can be created as Steve suggest. you can also generate HV sprites on the objects directly and again use textures to activate and animate them.
HEREs (http://www.3dtrainingonline.com/examples/morph_test.avi) a quick example. The bar is the reference object for a texture that activates the morph and acts as an alpha to reveal a new texture.

dukestreet
12-05-2003, 10:57 PM
Steve, the zip file and samples look good, only thing is I'm working on a Mac - and I couldn't get the plugin to load......

Spline God - the sample file looks interesting and I might try that. Although once I get started on it on Monday I might have a question or two for you.


Thanks,

D

Steve Warner
12-05-2003, 11:46 PM
Doh! :blush: It looks like both Fi's and SHIFT's plugins are for PCs only. I'm really sorry. Here's another boolean plugin that isn't PC specific. Flay lists this as compatible with version 7.0 of the software, so I'm hoping that the Lscript changes in 7.5b won't have affected it.

http://www.balo.com/downloads.shtml

Download the Animated Boolean 2 plugin. It basically creates multiple boolean steps and saves out each step as an object. You can then use this object sequence in Layout to achieve the animated boolean effect.

Hope this helps!

Steve

dukestreet
12-06-2003, 03:25 PM
Using the animated boolean plugin with an object that has endomorphs might work. That way if there is a displacement map on the object to make the sides of the tunnel look rough and the boolean object doesn't slide down the tunnel, but effectively digs this would be perfect. Add a few metaballs at the tip to make things change as it digs and I'd be set. I'm now wanting to go into work and try this all out! Ha!

Thanks guys.

Not ever having done one, would this be worthy of a tutorial? I'd do it if there was interest.

D

LittleFenris
12-06-2003, 04:17 PM
I would definitely add a tutorial like this to my library of downloaded tutorials. :applause:

SplineGod
12-06-2003, 08:55 PM
Originally posted by dukestreet
Using the animated boolean plugin with an object that has endomorphs might work. That way if there is a displacement map on the object to make the sides of the tunnel look rough and the boolean object doesn't slide down the tunnel, but effectively digs this would be perfect. Add a few metaballs at the tip to make things change as it digs and I'd be set. I'm now wanting to go into work and try this all out! Ha!

Thanks guys.

Not ever having done one, would this be worthy of a tutorial? I'd do it if there was interest.

D

Basically all you have to do is have the morph target for the tunnel have jittered sides to make it look rough. You can generate HV sprites for dust at the point where the digging is taking place. Throw in a few particles for debris and stuff.
HEREs (http://www.3dtrainingonline.com/examples/flow.avi) an example of the same technique to get water flowing down a tube using no particles or HVs.

Steve Warner
12-07-2003, 09:18 PM
Originally posted by dukestreet
Not ever having done one, would this be worthy of a tutorial?
I think that would be a terrific idea. :) Creating tutorials for things we've been challenged by, then worked through, seems to be a rite of passege for most LightWave users. And it's part of what makes being a LightWave user so wonderful. Everyone benefits. :beer:

@ Larry: Nice water sim! The plumber just left my house (and took my $300 with him), so my pipes are once again running like the one in your animation. :)

Cheers,

Steve

dukestreet
12-08-2003, 04:13 PM
Originally posted by Steve Warner
I think that would be a terrific idea. :) Creating tutorials for things we've been challenged by, then worked through, seems to be a rite of passege for most LightWave users. Everyone benefits. :beer:



that's what I was thinking - also by documenting it I'll most likely understand it a little better.

Spline God: I've been going over the physics of the project and it looks like the digging shots will occur at regular intervals (for this demo, probably 1 maybe 2 per second) which means I'll have to have multiple morphs. That's a good and bad thing - I'm hoping to go for an elegant solution, not go the brute force method.

The thing is that the parts that have been dug pretty much will stay the same through the whole animation. So having an iterative stepping for the digging, there won't be much blending, its really straightforward, but a little more time consuming. I think the results will look better in the end, regardless.

I have to go talk to the engineers this afternoon, so I'll try and get a sample posted tomorrow for feedback.

Thanks for all your help.

D

SplineGod
12-08-2003, 10:26 PM
Originally posted by dukestreet


Spline God: I've been going over the physics of the project and it looks like the digging shots will occur at regular intervals (for this demo, probably 1 maybe 2 per second) which means I'll have to have multiple morphs. That's a good and bad thing - I'm hoping to go for an elegant solution, not go the brute force method.

D
The solution I mentioned doesnt require multiple morphs, just one. By using texture maps you can activate the morph in varying degrees along the tunnel. For example you can use a gradient with distance to a null as its input parameter to open up the tunnel ahead of the digger. A second texture will keep the tunnel opened. You can animate the reference null in bursts forward and use HV sprites/particles etc to cover up any possible weirdness.

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