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View Full Version : Slow motion shattering window - prebaked MDDs or ready fractured objects



dsol
08-08-2013, 10:28 AM
Hey,

I'm hoping to start work on a music video in a week or two, and need to create a slow-motion shot (from a couple of angles) of a glass window shattering after being hit by bullets (but don't need to show the bullets!). The fracture tool in LW seems to generate pretty ropey geometry and crashes a lot, so I was wondering if:

(a) someone knew how to get better results, or...
(b) someone had an existing pre-fractured model for a glass pane, or...
(c) the above plus an MDD file with pre-baked shatter animation using physics

I've done some stuff (http://forums.newtek.com/showthread.php?134665-BBC-Radio-1xtra-quot-Bassphone-quot-promo) with the fracture tools and bullet before, but this video is super-glossy (and it's ultra slo-mo - which means you can't hide the detail needed) so I need a really nice realistic looking shattered glass.

I can pay some cash for pre-built solutions - though being a music video, the money is a bit tight. But I wouldn't want to take the piss :)

Any help/suggestions greatly appreciated!

Dan

nickdigital
08-08-2013, 12:10 PM
Is your glass object at some ridiculously large or small scale? Also it might help to subdivide your glass pane before doing Fracture.

Once you save out your simulation to mdd you can change the playback speed.

dsol
08-08-2013, 12:22 PM
Thanks for the advice. I'll try reducing the scale.
Does the scale affect the quality of the fracturing too - or is it just the bullet physics side of things that is affected by it?

nickdigital
08-08-2013, 12:36 PM
I can't recall if the scale affects Fracture. I just know that subdividing the geo more will make the Fracture algorithm more friendly. So for example, if you were breaking up a long beam of wood, you wouldn't want to have a really long six sided cube. You'd want more cuts. Fracture doesn't like super long polygons. (At least that's what I was told at a user group meeting).

stobbs
08-08-2013, 12:41 PM
There's a pre fractured model on turbosquid if fracture tool doesnt behave..

http://www.turbosquid.com/3d-models/3d-glass-shattering-model/639694

dwburman
08-08-2013, 01:58 PM
SplineGod did a few videos on fracturing things without the fracture tool.
You might be able to get cleaner results that way.

http://www.youtube.com/playlist?list=PL4BC9CAD35CE70071

OnlineRender
08-08-2013, 02:41 PM
use bullet and use the time function inside the dynimacs tab ..."not at pc" but its there and can be controlled with [E] , fracturing is easy ... but I still preffer to use Hard FX and mike greens MGBREAKUP plugin and Matt also wrote a script to enable HardFx on all layers , which helps big time , either bullet or hard fx will do the trick ...

another tip would be to export each frame as a savetransform obj then reimport back into the scene and you can then set what frames what object sits on "good for controlling speed "

OR JUST cheat in AFX and slow everything down :) pixel blending on

EDIT l or if you have element3D I think there is glass shatter model presets

OnlineRender
08-08-2013, 02:45 PM
how many bullet holes ? does the glass shatter around the points of impact ? or is just a general "KAABOOM"?


edit MG VORRONI SHATTER is the plugin

but breakup has a bullet control point " actual bullet hit"

OnlineRender
08-08-2013, 02:56 PM
http://lightwiki.com/mediawiki/images/5/59/Break.jpg like so , If you know where the impacts are you can do some nice sim..

Ryste3d
08-08-2013, 02:56 PM
Somthing like this? (glass on the left is Video Co Pilot action essential)

http://www.youtube.com/watch?v=-RAZTbk9ERQ

OnlineRender
08-08-2013, 03:09 PM
enjoyed that Ryste

BeeVee
08-08-2013, 04:00 PM
Or, just use ChronoSculpt! It's ideal for exactly this purpose. I'll show you at the London meet :)

B

dwburman
08-08-2013, 04:55 PM
The fracture tool in LW is cool, but (at least in my experience) generates geometry with holes and stray points and weird artifacts with some geometric shapes. A simple plane of glass might not be too bad, though.

robpowers3d
08-08-2013, 05:24 PM
I could not resist to offer my suggestion for a solution to this desired effect. BTW, ChronoSculpt would make controlling the speed and editing the glass dynamics simulation from Bullet a 2 min job as well and is a perfect tool for this.

But I also want to share some tips on the fracture tool. If you plan to fracture something you should try to subdivide it nicely to prevent the fracture tool having to slice across very large polygons. When you do that and use the background geometry function to place something simple like sphere in the background to control where you want the fracture to focus on your glass then is works very well.

You would want to select the stray points after you fracture and delete the ones not attached to any polygons if any are generated. But that is a quick step. I will attach images to show my process.

116224116225

116226116227

XswampyX
08-08-2013, 06:08 PM
Here's another way.


http://youtu.be/Gogn61UlqkE

More safety/cartoon type glass.

pinkmouse
08-08-2013, 06:28 PM
I was experimenting with this a month or so ago, can't find the rendered version, but here's a quick preview of where I got to:


http://www.youtube.com/watch?v=3X_LQyyAR1M&feature=youtu.be

edit: Unweld! That's the command I was searching for. Cheers XSX! :D

robpowers3d
08-08-2013, 09:03 PM
I just put together this quick tutorial to show my process and offer some tips:

http://www.youtube.com/watch?v=yqexUbvLTxg

CaptainMarlowe
08-09-2013, 04:24 AM
Nice tut, thanks.

alexs3d
08-09-2013, 05:27 AM
thanks for the tutorials, nice overview

pinkmouse
08-09-2013, 05:45 AM
Thanks for the shattering tutorial Rob. A bit less work than my previous method.

However, much as Rob would love you to buy his new S/W, ( :D) ), you don't actually need ChronoSculpt for this. You can create quite satisfactory results with the an envelope for simulation speed in World Settings.


http://www.youtube.com/watch?v=QTxgMjHyzJE&feature=youtu.be

Oh, and I've managed to break Bullet in 11.6. Whilst playing with the above sim, the whole computer locked up. A hard reset later, booted up Layout and saw the result below:

116242

I've killed it! Reseting configs didn't help...

edit: Third time of deleting configs lucky! Got Bullet back!

BeeVee
08-09-2013, 06:27 AM
How did you reset your configs and also you should have a plugin called dynamics.p in \support\plugins\animate.

B

OnlineRender
08-09-2013, 06:47 AM
this is where you can have a lot of control using hard fx , it has certain elements for moving pieces and controlling there time ... plus you can weight map / pin the corner I dont think you can do that in bullet

Thomas Leitner
08-09-2013, 06:55 AM
....
The fracture tool in LW seems to generate pretty ropey geometry and crashes a lot, so I was wondering if:

(a) someone knew how to get better results, or...
(b) someone had an existing pre-fractured model for a glass pane, or...
(c) the above plus an MDD file with pre-baked shatter animation using physics

I've done some stuff (http://forums.newtek.com/showthread.php?134665-BBC-Radio-1xtra-quot-Bassphone-quot-promo) with the fracture tools and bullet before, but this video is super-glossy (and it's ultra slo-mo - which means you can't hide the detail needed) so I need a really nice realistic looking shattered glass.
....

As you mentioned the fracture part of this will be the most difficult to achieve. I donīt think that you can achieve the look of shattered glass with LWs fracture tool on its own.

Take a photo as reference and use a technique like XswampyX recommends:


Here's another way.


http://youtu.be/Gogn61UlqkE

More safety/cartoon type glass.

After this use fracture tool on single parts (mostly from the impact spot) to shatter it more.

For the animation part: fix some geometrie around your hole (maybe animate it with a morph to get some cracks without breaking complete).

One thing that could become difficult in this case is that you cannot render the preshattered glass as intact. You have to exchange two objects. At normal speed this works, however with slow motion it can become a problem (maybe you can use an animated clip map to reveal/hide the objects.

And if you need to change the playback speed you donīt need to leave LW for Chronosculpt, you can adjust the MDD speed in the MDD reader (probably you know this already)!

ciao
Thomas

pinkmouse
08-09-2013, 07:00 AM
Quick render with materials. Needs some particles as well I think. :)

116243


How did you reset your configs and also you should have a plugin called dynamics.p in \support\plugins\animate.

B

Hi Ben. Unhid Libs/app support/... (ML 10.8.4!), dragged configs folder to trash, and restarted. Third time it actually stuck, and I got everything back.

pinkmouse
08-09-2013, 07:04 AM
this is where you can have a lot of control using hard fx , it has certain elements for moving pieces and controlling there time ... plus you can weight map / pin the corner I dont think you can do that in bullet


As a recent LW returnee, I've never used HardFX, just got stuck straight into Bullet. Perhaps I should explore the old stuff more, as weighting/pinning would be quite useful.

OnlineRender
08-09-2013, 08:04 AM
http://youtu.be/RIHHje1sNLM




some stuff

OnlineRender
08-09-2013, 08:06 AM
http://youtu.be/6dmpI7urTKQ ident

dsol
08-09-2013, 08:44 AM
Everyone THANK YOU so much for all your feedback on this. Rob, in particular, for doing a great tutorial! I think the problem I was having was because I wasn't subdividing my glass pane enough (I only had about a third of the number of divisions in rob's tutorial).

Now if you'll excuse me, I'm gonna go and break some glass.... :)

dsol
08-13-2013, 05:07 AM
Here's my first attempt - slow motion shattering glass. There's a few glitches, but this works pretty well. The big breakthrough came with Rob's tut on the fracture tool. I hadn't used polys as shatter objects before, and they work really well. And upping the subdivision on the shape before running Fracture really helps (which is weirdly counter-intuitive as boolean operations usually get slower/more glitchy as geometry gets more complex!)


https://vimeo.com/72258752

prometheus
08-14-2013, 07:08 AM
And please do check the spiderweb chatter thread if you have missed it, some more additional tips on how to fracture in a spiderweb or glassbullet impact way.
I posted an object template that you can see the results from and also use as template...I noticed some errors in it and I didnīt check stray points etc, but I think it might be worth checking.
I used a sphere with z axis start, deleted half of the sphere because I then flatten it and I donīt want double sided surface, extruding it and fracture it with background points.
Read more about that...

Thread...
http://forums.newtek.com/showthread.php?137008-Spiderweb-Shatter&p=1339120#post1339120

image of object template...
116363

object template...
http://forums.newtek.com/attachment.php?attachmentid=116332&d=1376424939

you could also try and jitter it too slightly.

dsol
08-14-2013, 07:22 AM
Thanks for the link, great to have some good pointers on how to create spiderweb shatter patterns - v important for glass!

JohnMarchant
08-14-2013, 07:24 AM
Thanks for all the help everyone. I have another question when working with glass you can see the fracture before it actually break because of the transparency. How do we get rid of that. Cant morph it as the two objects have different amount of polys. Is it still the case that we have to use a non shattered object and then replace with the shattered one just before we shatter it.

OnlineRender
08-14-2013, 07:33 AM
you are over thinking mate, clone the object one fractured one not and use the dissolve in the objects rendering settings and switch them in the graph editor "liner"

JohnMarchant
08-14-2013, 07:50 AM
First time ive been accused of over thinking :):). So its still dissolve from one to the other, thought there might have been a way using only the shattered object. Like make cracks disappear until the bullet effect takes place. Thanks for that.