Hi, I have a bit of a tricky problem

I have a job which originally started out as a still image of a group of ‘tetrisy’-type bricks seemingly randomly arranged as though they have fallen onto a flat surface.

My task is now that I have to make an animation of the bricks falling into the same position.

I have been through the reactor tutorials in Max and they are all well and good, however they only seem to let me dictate where the objects will start, not where they finish.  I had the obvious idea of starting off in the end position, reversing the gravity and then playing the animation backwards - however this looks unnatural as there will be no bouncing/settling at the start of the reversed animation - I thought of animating the gravity parameter which could give a bounce effect, but there seems to be no option to animate the gravity pull in reactor.

Would anyone have any suggestions as to how I would go about this task?

Windows XP Professional SP3
Intel Xeon CPU 3.2 GHz
3.25 GB RAM
NVidia Quadro FX 4500

I tried to attach an image to the original post but seem to be having real trouble for some reason - hope this works!

This is the final position where all the fallen bricks should end up.

Windows XP Professional SP3
Intel Xeon CPU 3.2 GHz
3.25 GB RAM
NVidia Quadro FX 4500

	Attachment

I doubt is posible to do it in reverse. Also the layout dont looking naturally random fallen. But its just my opinion, I donk know Max well.
There are 3 case I know, with reactor the standard way(forward):
- max friction, zero bounce: the objects fall to the right position and stay there, but the animation looks so unnatural :)
- allow bounciong, sliding, then the objects will dont fall to the place like on the picture, but the motion looks cool :)
- use some “helper wall”, deflector or something to guide the fallen pieces to the right position(to prevent bouncing away). With luck and some try, I think you can force almost to the same place the objects, as on the picture.

Here’s my meager attempt to do it using keyframes.
Out of time so I’ll have to leave it as is…

:)

Lasts ten seconds so wait for it to repeat.

Max 2012
Windows 7 64 SP1

	Attachment
blocks_drop.swf

Thanks for the reply Atom - it’s going to be tricky using Reactor, eh?

Holy tweens Don, I wasn’t expecting anyone to go to those lengths (I didn’t even give you the Max file), but many thanks - it’s well on the way!  I was thinking I would have to end up using tweens/key frames anyway - just seems like a lot of work and trial and error when there might have been a way around it - guess whichever way I go I’m going to have a lot of animation previews to sit through :-) Might even try a combination using very tight Reactor parameters, create the animation, then tween/keyframe to finish off positioning the blocks.

Will post up the finished render.

Thanks again.

Windows XP Professional SP3
Intel Xeon CPU 3.2 GHz
3.25 GB RAM
NVidia Quadro FX 4500

you could have them individually fall down a tube or cylinder. this way thier placement wouldnt move

Well it took me a whole day of trial and error in Reactor, changing the starting heights and angles of the bricks before I was satisfied with the results.

I ended up putting each block through the havoc calculator individually (with a little helping hand from an inverted cylinder on each to nudge it towards its final position - thanks for that suggestion), then once that was done I keyed in its original coordinates and rotation to make it exactly like the render in the original post. When each block was finished I then made that into a static dummy object to enable incoming blocks to react to it.

As I said - a lot of trial and error, as once I’d changed the finished coordinates to their original positions there were more often than not interpenetrating blocks - I just kept redoing each block until it looked right, then building up the scene with the next block.

I’ve attached the final animation as a swf - I think it looks pretty natural for such an ‘unnatural’ and not very random looking final position.

Windows XP Professional SP3
Intel Xeon CPU 3.2 GHz
3.25 GB RAM
NVidia Quadro FX 4500

	Attachment
fallingblocks.swf

Sa-weet!
Wish I had read the actual object shapes, would have been a lot easier.
Nice job!

:)

Max 2012
Windows 7 64 SP1

Make gravity a negative number so they “fall” up from their original position and then reverse the rendered frames…?

3ds Max 9 thru 2013
Windows 7 Enterprise 64-bit OS SP1
Dual Intel® Xeon® 6 core X5650 @ 2.67GHz CPU 36GB RAM
NVIDIA Quadro 4000
450GB HDD (x3) and 2TB HDD

3ds Max 2012 Certified Professional Models to Motion

Interesting.  I’ve never thought of that; I’ll have to give it a try.

Chris Robinson
http://www.supercoonstudios.com (Under Development)
3ds Max 2011
Dell Precision 690, Intel Xeon Dual Quads @ 2.66 GHz, Dual NVIDIA Quadro FX4500s, 12 GB RAM, Windonws 7 x64

Let me know how it works out...my fear is that the collisions may look “funny?”

3ds Max 9 thru 2013
Windows 7 Enterprise 64-bit OS SP1
Dual Intel® Xeon® 6 core X5650 @ 2.67GHz CPU 36GB RAM
NVIDIA Quadro 4000
450GB HDD (x3) and 2TB HDD

3ds Max 2012 Certified Professional Models to Motion