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pekka varis
07-11-2018, 05:15 AM
Again I have a great animation & video project to fill my summer days :)
I need top make a wooden trunk that splitters and shatters to a little piecies. The "seam" or "edge" of the destruction area should be quite sharp, a little bit like a burning cigarette.. See the images here:

142185


Then the small parts should fall & lie down on floor, affected by dynamics. Hot achive this effect?

Pekka Varis

ianr
07-11-2018, 07:29 AM
Again I have a great animation & video project to fill my summer days :)
I need top make a wooden trunk that splitters and shatters to a little piecies. The "seam" or "edge" of the destruction area should be quite sharp, a little bit like a burning cigarette.. See the images here:

142185


Then the small parts should fall & lie down on floor, affected by dynamics. Hot achive this effect?

Pekka Varis

Pekka
Trees don't do nibbled bits, they are built of rings of yearly growth.(look at lightning

strikes or shell explosions on trunks, you have shattered peaks in the trunk)

So I would build a tree trunk in cylinders inside one another (say 3 to 5)

Next in modeler subdivide these tubes or band saw/knife to the areas you want

to be spilt or damaged> then on those areas run Fracture/ Voroni to give random breaks.



Next learn Bullet from Lightwave tutorials, then shatter the top of one of these

cylinders tweek until the timings are right for your taste. (Re-Sim)


Now repeat on other cylinders Fracture/ Voroni > Now put ALL cylinders together

with a obvious height difference so we can make a ruined peak to this trunk.

Then in one layer Re-Sim in Bullet. Throughout watch your polycount/ pieces & ram usage.

Good Luck.

MonroePoteet
07-11-2018, 10:10 AM
Depending on how each piece of the ground-up tree should look, you could either use Bullet or a Particle emitter with an Instancer.

Are the small pieces going to look like wood chips? Or ash like a burning cigarette? Or fairly sizeable pieces of wood which bounce and scatter on the ground? So, for example, if the animation is intended to show a tree trunk going through a wood chipper, the resulting pieces would be very small, look like wood, be fairly consistent in size and form a linear pile / line on the ground. In that case, perhaps a Particle emitter with an Instancer would be easier to set up and faster to calculate.

If you need the pieces of wood to have volume, interact with each other, and bounce around on the ground, Bullet may be the right solution.

Also, what's the target version of LW?

mTp

pekka varis
07-12-2018, 04:20 AM
LW 2018 is my version. I have to now study the Bullet. And make a simple test scene following your solutions. Thanks ianr and MonroePoteet !!

MonroePoteet
07-12-2018, 11:38 AM
LW 2018 is my version. I have to now study the Bullet. And make a simple test scene following your solutions. Thanks ianr and MonroePoteet !!

OK, although from your storyboard drawings ParticleFX still might work. Sample scene attached.

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MOV File: 142213

The log is three layers: the trunk itself, the Endcap, and layer 3 is the Woodchip for the Instancer.

The Endcap has ParticleFX applied in the FX tab, the emitter is set to Object-Surface, and the birth rate is controlled by an envelope so it stops when the Endcap stops. The Endcap is moved down the Z axis as the log is chipped.

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The endcap also has an Instancer applied, with the instancer type set to Particles. The Woodchip is the instanced object with random Scale and Rotation applied.

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The trunk / log vanishes using a moving Transparency channel, which is a Black&White image moved down the Z axis timed to the Endcap motion.

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The Ground plane has Collision FX applied to it with its parameters adjusted to get a little bit of a bounce (Bounce / Bind at 130%), scattering (Roughness), and having the Particles stop (Friction and Fix powers).

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As a detail, the Wood surface of the Endcap is moved in positive Z to make the texture change as the Endcap moves and the log is ground up.

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The size of the instances (wood chips) could be made substantially larger, but ParticleFX always uses a spherical collision object for each particle, so they wouldn't pile on the ground very well. If you need larger "chunks" of the log in the pile, you'll probably need to go with Bullet.

Have fun!
mTp

P.S. After posting the scene, I noticed in the full-size render that the 100% Transparent Bark surface leaves a refraction "smudge". To fix this, you'll need to set the Bark's Transmittance color to pure white:

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pekka varis
07-13-2018, 12:47 AM
Amazing help man!! I study this now : )

MonroePoteet
07-13-2018, 11:04 AM
Glad to help, if it's similar to the effect you are looking for. Be sure to look at the various tabs in the Emitter panel - the particle(s) size, resistance, initial motion, force of gravity, and so forth are located in various tabs for fine-tuning control of the particles.

mTp