View Full Version : FXWars! Catapult! (Trebuchet) : Derby-Q Salano

07 July 2004, 08:28 PM
Good idea... so far I did succesfull dynamics tests for both the arm and all the wire work between the arm and the frame... In the throw test I managed to throw a rock over 500 meters... all with realistic proportions and weights ofcourse. I put a brake on the arm ones it reaches a vertical position, to avoid problems with the upcoming wire work... Hope you like it...

Early Animation Test

Dynamics Test (

07 July 2004, 08:38 PM
did you key the release of the rock? or is there a hook of some sort?

07 July 2004, 08:43 PM
I keyed it, I still feel it's a challenge to create something using dynamics... Not to create something using nothing but dynamics... nobody will ever do that... the use of dynamics here is just a help here...

07 July 2004, 09:18 PM
Here's a dynamics test for the ropes. There's going to be 8 animated ropes in the rig

Rope Test (

07 July 2004, 09:34 PM
that is nicely done. what prog is it, looks like maya.

07 July 2004, 09:41 PM
Good guess. And thanks...

07 July 2004, 11:17 PM
That is really nice. I think it would be worth having the wood in the frame flex. Even it you can't simulate it, maybe just have a couple of bones driven by the arm. It would add a lot of realism. Good stuff.

07 July 2004, 11:44 PM
Damn dude! I can't believe you put all that together already. Looking great.

07 July 2004, 11:53 PM
I think your ropes are moving like they're underwater. Maybe increase the gravity? Have you taken into account that whole thing with Maya and gravity when it comes to centimeters? Gotta pump up that gravity to.. 98 I think?, if you're working in centimeters..

Other than that it looks great. You're implementing dynamics more as one should in a production, ie. make it look good, not neccessarily deliver the most physically accurate launching. Nodoubt much more timeefficient than trying to do the whole thing dynamically :).

I'm toying with a trebuchet as well here, but I'm having a beast of a time getting the wires to do their thing. In your implementation, can you cock the weapon by pulling the arming-wire? Ie. can you arm it physically, or is it firing from the getgo?
I'm trying to do arm it "physically correct" (ie. pulling the arming-wire down and connecting it to the releasepin) but it's not going too well.

On a possibly related note, how'd you attach the ball to the wire?

Anyway, what you've got looks promising. And the model itself looks intimidating already.

07 July 2004, 12:26 AM
Good point, Novacaine. Although these are rigid bodies... so wont be able to do this dynamically, perhaps with bones yeah...

Gaggle, you're right, the ropes are floating, but that's caused by my high value in damping, not by the gravity, I need to fix that, but dynamic simulations can result in terrible noise in the motion, hence the high damping... Units in Maya are in meters according to me, do this: create an object, add gravity to it and playback exactly 1 second, your object will end up at y = -4.9 right? If you would put 1 second in the physical equation,

(y being distance, a acceleration and t time)

2 * y = a * t^2

You get

2 * y = -9.81 * 1^2 s^2 m/s^2

y = -4.905 m

Common mistake though, besides if it was cm instead of m it would have been 981 cm/s^2 which is 9.81 m/s^2, not 98.

If you are not sure do a test like the one above...

On an other matter:

You can pull your arm down using a contraint for example a pin or spring, whatever you like, just animate the anchor point, I did that, but the ammo needs to be dragged in the slide though and that took a bit too much work.

The Ball is connected on the wire using a pin constraint, of which the on/off attribute is animated, so the constraint will brake after release...

Hope this is helpfull...

Thank you for the comments

07 July 2004, 01:43 AM
Wow that looks great. Your almost done and I can't even keep the pieces from going through each other... :banghead:

Luckily I have a month to figure it out.

Can't wait to see the full thing.

07 July 2004, 02:48 AM
lol, ya, after seeing that first maya test, i quit! :p

but I was gonna ask, so can we also use expressions? is that fair?

07 July 2004, 07:56 AM
I think the challenge is not about making a completely driven dynamics challenge...I think using an expression and a key for triggering a dynamic even is necessary, since a trebuchet is operated by humans in real life, there HAS to be human intervention in the animation, I only use a key to unlock the rock, and that's about it I think, the pulley that's rolling across the rope is also keyed, but the main things, the throwing of the rock, swinging of the arm, the weights, that's all dynamic... I think I'm doing it by the rules :)

Thanks for the comments.

07 July 2004, 02:47 PM
hehe, i wasnt asking about you! :p
I was just asking is it ok to mix expressions with Dynamics in LW?

your entry looks great! like I said, dont know if I even want to try this in LW!

07 July 2004, 09:01 PM
i feel stupid asking this question, but the rope that is around your beams, how did u do it, I know its a nurbs curve and an extrude, but if i make the beam live the points are right etc, any clues.

07 July 2004, 10:56 PM
What do you mean by beams? Most ropes are just cubes with pin constraints..., the ones to the pully are dynamic curves

07 July 2004, 11:00 PM
sorry, i know how to make the rope dynamic, just not get it to wrap so neatly around the frame of the catapult. Like where it goes from the pegs to the frame and wraps around a few times.

If the frame is square it wraps nicely round it, making the surface live doesn't work.

07 July 2004, 11:03 PM
It's modeled, not dynamic. That's just detailing

07 July 2004, 11:05 PM
yes i know, i want to know how u get it to wrap round the beam like that

07 July 2004, 11:22 PM
Well... Quite some ways to easily do this. Model a loop either using smooth, a hp torus or an extrusion along a curve... take the torus: take a quartre of it, delete the other faces, fill hole on the remaining, extrude the new faces and duplicate the corner so you get a complete loop... Placing it shouldnt be hard, place the pivot point on an edge of the beam once the first loop is done, then duplicate and curve drag over that edge... I don't know if you were looking for something like this... It's pretty basic modeling though...

07 July 2004, 11:25 PM
thanks for that. I'm not really a very good modeler, hence my basic catapult and building

07 July 2004, 11:34 PM
The more you model the faster you'll figure out how to model stuff...If you want more details, I can write out some tuts if you want...

07 July 2004, 11:37 PM
that would be very nice of you to do that, a tut would be great.

07 July 2004, 01:19 PM
First I'm working, cause I didnt have time yesterday.

Texturing done I think, I'm not going to add more work on the weight, which I should, because it will have some motion blur in the end.

Now the rest of the wire work and I can put this in a scene...

07 July 2004, 01:35 PM
Another render:

07 July 2004, 01:41 PM
Hey Man, you are fast, i guess you just have that to do :p just kidding hehe..

Good luck! I love the way your rope slides along the pulley...really cool.

How long do you plan on working on this thing?

07 July 2004, 01:56 PM
Well my main goal these days is fill up my portfolio for when it gets online within a few weeks, when I lack inspiration I like to do these challenges... keeps me in shape, normally I go for speed modeling, to increase productivity, but I like medieval stuff so I jumped on this one as well...

I think I will be done with the treb by tonight, after that I think I will put it in some sort of scene... don't exactly know which direction I will take on that though... Since we have a month, I might just model an entire castle :)

07 July 2004, 09:06 PM
I think the treb is finished, now I will have to focus on the wall that gets crushed.

Let me know what you think.

07 July 2004, 09:19 PM
There. I think I'm happy with the animation, the rock is thrown a virtual 750 meters... which isn't bad since the weights and measures are accurate... Just a hint: the rock is released when the speed is at 45 degrees with the floor...

Final Trebuchet Playblast 660kB (

07 July 2004, 09:21 PM
Hey man,

Maybe a little comment Texture wise, you could, i am sure you know that, maybe try to give it some history, cracks, chips, dents, what have you! :) If you can and could really give it some aggresive look...

my 2 cents

07 July 2004, 09:23 PM
Yeah I should, shouldnt I... OR maybe it's a stealth prototype :)

07 July 2004, 09:30 PM
Hehe Whatever you choose... :)

Really cool simulation!! Did those trebuchet really fire 3/4 kms away?

07 July 2004, 09:33 PM
And a textured animation:

I remember the movie the Gladiator, where in the extra's on the 2Disk DVD, they talked about how they could fire a bolt like 100m far, although in those days, they could reach up to 500-1000m... I find it sad that knowledge in crafts like that (same for Japanese Katana's) were lost in evolution... (

07 July 2004, 10:22 PM
In researching these things today I found someone has one that can launch an 8 pound pumpkin 930 feet so there is little doubt the full size, full weighed versions could do 750m.

07 July 2004, 10:37 PM
According to wikipedia the largest trebuchets shot about half a mile, apparently. Pretty darned far indeed.

Still looking good derby, got a real headstart on me (been too busy this week to get a lot done!) and mine is going to end up looking a whole lot like yours, which aint good! Got some good ideas to mix it up though. Will look forward to seeing what you come up with for the wall.

07 July 2004, 10:39 PM
If I were a pumpkin I wouldnt fly to high either... but seriously, I also doubt I'm right about the distance... in my final version, my rock hits the ground at 670 units from the treb... not very realistic maybe... But as I said, these days, they don't get the distances that were reached in those days... the Romans were quite good at the building and operating of those things... I should do more research in historical based texts for the distance... but you know what... I don't really care if it would have been possible... instead I spend my time modeling...

07 July 2004, 10:42 PM
Rabbit: Half a mile? Cool well, I'm between half a km and half a mile... I'm happy :)

07 July 2004, 12:51 AM
Looks really cool derbyqsalano, good action going. The varioues wires adds nicely to the action. Do they affect the machinery directly? Or are they of the "there to make things look pretty" type?

Oh also how's the ball released now? The sling mechanism looks pretty accurate so maybe you switched away from the animated constraint?

Also also imo the wires remain underwater-esque. Not really a problem, just.. you know, if you're looking for something to tweak that could be one area. ..actually I guess all the movements feels a bit slow/dampened to me.

If you're really concious about going the extra mile you could also score points by vibrating the whole rig as it fires. Show all that energy being absorbed into the frame.

There's a bit of an odd jump in one of the sets of wires, right before it launches. Is that on purpose? Like it hasn't settled correctly or something..

07 July 2004, 01:04 AM
Well normally the wires should be set correctly, although they do seem too slow... these wires however are 8 meters long... the size might give a damped feel, or perhaps the wires aren't heavy enough... well I don't know if I will tweak more, I've had a rough point that took me like 3 hours to solve, after that I don't think I will tough any of the controls... Just too risky, but I'm sure next time I will work much faster with the dynamics, and I will be able to prevent the problems I got, and tweak more afterwards, for now this is gonna be it though, the trembling would be a nice tough... The wires are mainly just detailing, to make it a precise model of the ones used by the French in Medieval times...

And yeah there are some artifacts in the motion, I noticed that too, I tried getting it out, but I almost got stuck with no setup at all... so I got scared and left it the way it was :)

The unlocking of the ball is still keyed... if this is against the rules then ban me, because I really would like to see a setup that works, with a completely dynamic unlocker... Sure you can make a hook and a ring... but 1: hooks and rings are very dense and will result in either crashing dynamics or super slow dynamics. and 2: Once you make it work, you still have to get the ball of the hook... In my model, the ball is in some sort of bag, kept closed by a little stick, the wires that come from the middle of the arm and go to the ball are pulling the stick out when the ball is further away from the arm, then the length of the unlock wires... hope you're following... Well to do it like that, I would have to work with a bag, constructud by squares and constraints... in the end I wouldnt get there, trust me... there is too much that can kick a simulation in the nuts and frankly it should be done with keying if possible... hence the unlocking key... which is the only key in the simulation btw...

07 July 2004, 01:17 AM

Finally LW does something Maya cant!

You can use an event to cut a point loose, with the ball parented to it!


07 July 2004, 01:20 AM
Keying of the release is allowed.

I wouldn't get too excited yet Howard, we have a long way to go to match this one.

07 July 2004, 02:04 AM
Hate to break your party Howard, that's exactly how I released the ball... breaking a constraint...

07 July 2004, 02:12 AM
In Lightwave you don't need to set a keyframe for this, you can set a collision event so that when the ball crosses, it is automatically cut. Is this possible in Maya as well?

07 July 2004, 02:25 AM
The way I ran it in my test was an expression:

if(trebArm.rotateX<85){ = 1;
else { = 0;

This is melscript but it can be translated to any other program with an expression language. This gaurantees that it is still dynamic by telling it to release the ball at a certain angle. You would have control over the angle to experiment for your optimal release, simulating a bent hook.

Something a bit more indepth but necessary to insure the constraint doesn't become active again if the arm dips below your set angle would be:

-create attribute on your ball/shot called isReleased

shot1.isReleased = 0;

if(trebArm.rotateX<85 && shot1.isReleased != 1){ = 1;
else {
shot1.isReleased = 1; = 0;

07 July 2004, 09:27 AM
That's not a dynamic trigger either... so I think we're in the same ballpark... I can just release my key if the arm is rotated 45 degrees with the ground, sure, but in the end the result is the same...

Btw Coryc: there's nothing Maya can't do :)

And there are collision events indeed...

07 July 2004, 11:50 AM
Btw Coryc: there's nothing Maya can't do :)
And here I thought it was you that was doing this.:D

07 July 2004, 11:51 AM
Keyframing the constraint one way or another sounds good to me anyhow. Maybe it'd be fun to do a "physically correct" pouch just as a test though, without the whole arm swinging.. just to see that it can be done. Hm I'll go check that out, what else are weekends for :).

Regarding your dynamic "pretty" wires derbyqsalano. Are they all rigidbody pinconstrained wires?
Anyway if the pretty wires doesn't influence the main simulation, I'd think it possible for you to turn the cache off selectivly for the relevant objects, and let them resolve without having to simulate everything again? I totally understand what you're getting at with the whole "it works now, I'm not ****ing with it anymore", and that's probably the best route to take so you don't get stuck tweaking small stuff. If you do get the urge to fix it at some point though the cache (wether rigid- or softbody based) should be toggleable. Rigidbodies in particular have that cache-switcher node thing going so you can make several caches and mix between them as you see fit.

07 July 2004, 12:06 PM
I did a complete pouch ones, but the key is still a constraint that brakes...

The wires are about 50% dynamic curve and 50% rigid constrained cube chains... basically, if the wire needs to carry something, for example the pulley, it's rigid... I didnt get the dynamic curves to carry a pulley yet...

The simulation is about 10 fps, so resimulating it isn't so terrible, I just have to learn to work more with solvers and caches, cause I got plenty of problems on that matter

07 July 2004, 03:59 PM
That's absolutely amazing! As a newbie trying to follow this challenge, I'd love to see a tutorial on a few things here.. The modelling wasn't too hard, but dynamics can really be a bitch! :) A tutorial from you on ropes and trebuchet-dynamics would be very much appreciated, as I haven't been able to find any tuts that helped me much. They're all about particle effects and stuff like that, not simulations.

Right now I'm stuck on the part where the projectile leaves the trebuchet :) Tricky stuff, tricky stuff!

Again, amazing work!

07 July 2004, 07:41 PM
Can I toot my own horn? It's probably in poor taste...
I just.., if you're using Maya you can download a simple Trebuchet scene from my thread ( Maybe you can dissect it to learn some stuff. If I'm not much mistaken it uses the same basic setup as derbyqsalano, minus the goodlooking part :).

derbyqsalano, apologies if this is out of line?, I don't mean to step on your toes here.

07 July 2004, 09:18 PM
Thanks alot Gaggle, I'll take a look at it as soon as my girlfriend gets off my workstation. I never should have allowed her to start playing Neverwinter Nights.. *sigh*


07 July 2004, 08:29 AM
That is amazingly complex. With the real ropes and the motion blur, you are going to have a killer render :twisted:

And go NWN!

07 July 2004, 01:13 PM
Echo: I will try to perhaps do some basic tuts on beginning animation, I don't know if I'll find much time though... we'll see...

Thanks for the comments guys.

I don't mean to step on your toes here. Gaggle: I shall hunt you down! ;)

And on the matter of the thread, I decided there should be some life in my offensive part of the scene, I got a treb that's being build and one that's being loaded, in total I will go with 3 trebs, two of which are static, the other dynamic. I will have a number of workers, arming, loading, transporting stones and parts, and a number of soldiers, not an army, like 10 each or so... presuming the army is further ahead :)

Here's the base model of the worker, I got multiple textures of the clothes and will shape some variants of the mesh.

I hope this is allowed in the challenge.

07 July 2004, 02:14 PM
Here's an update: Variations in the weight of the person.

07 July 2004, 04:01 PM
I can't wait to see this scene finished! :thumbsup:

07 July 2004, 04:29 PM
Thanks :)

Here's a quick demo of some random generated workers... Don't play the animation, just drag through it, I didn't want to post 21 images, so here's 1 mov file.

The length of the guys will finaly be modified using skeletons.

07 July 2004, 05:34 PM
Sweet Jesus you're really taking this all the way.
Color me impressed.

07 July 2004, 08:55 PM
I wrote my Worker Generator, it creates a worker with random proportions and facial features (which I can still alter afterwards), random clothing and face textures, depending of what kind of worker, I'm going with three kinds, as an excuse for the many colors in clothing...

07 July 2004, 09:25 PM
Pretty darned impressive man. You say you are working on this for your reel? Surprising you don't already have a job!

I had thought I might like to include something like what you're doing with the workers but I don't know if I have time to implement it. I'm really glad to see you're taking this to the max because it's motivating to try to keep up.

07 July 2004, 09:29 PM
Thanks for the kind words, I currently am teaching at the only school where they teach Maya in my country, it's parttime and I need a job in production, I haven't found a company here that works with Maya. And for the moment I can't move to another country... I'm planning on starting a school though...

07 July 2004, 09:39 PM
Echo: I will try to perhaps do some basic tuts on beginning animation, I don't know if I'll find much time though... we'll see...

Thanks for the comments guys.

Gaggle: I shall hunt you down! ;)

And on the matter of the thread, I decided there should be some life in my offensive part of the scene, I got a treb that's being build and one that's being loaded, in total I will go with 3 trebs, two of which are static, the other dynamic. I will have a number of workers, arming, loading, transporting stones and parts, and a number of soldiers, not an army, like 10 each or so... presuming the army is further ahead :)

Here's the base model of the worker, I got multiple textures of the clothes and will shape some variants of the mesh.

I hope this is allowed in the challenge.
Derby-Q you can add as many bell and wistles as you want, as long as you have a Trebuchet animation at its core.


07 July 2004, 10:55 AM
Wow, Derby-Q Salano is on a roll again.
Extremely nice work, as usual!

Too bad your qualities don't get the chances they diserve!
(I know, we live in the same country)

Maybe you could start a Pixar office overhere? :thumbsup:

07 July 2004, 06:32 AM
Great final anim posted ! There was a mention or 2 of "underwater wires" but as soon as I saw the anim , I thought "wow , monster Treb!" . To me it looks more like a rotoscoped video of a very large Treb ( A.K.A. ... very very convincing) .

If I were you , I wouldn't touch a thing ... it's really amazing . That freakin' huge counterweight comes to , almost , a complete halt after letting the missle release . To me , that means it is so well designed that all energy is transfered to the projectile , and little is left for the counterbalance to slowly degrade .

The whole feel is tremendous and to me , flawless . I won't comment on potential ranking etc , but I must say I am very very impressed with the way the mass of this device is conveyed so accurately . I think a person really get's a good feel for what these incredible battle machines must have looked like , even from our technically advanced perspective . I can't even imagine what people of those times must have thought when they first saw a very large Trebuchet fire a heavy stone .

Excellent job & Congrad's on really nailing a very difficult challenge .

07 July 2004, 11:26 AM
i have a question about dynamic curves in maya. i work with maya 5 is it possible or do you have to have maya 6 for this type of thing?

07 July 2004, 11:29 AM
studio: thank a bunch

MrWyatt: Dynamic curves is a feature in Maya 6 only, but you can get the same result when you make cubes, connected to eachother with pin constraints as a chain.

07 July 2004, 08:16 PM
Time for some goodies, the Worker Generator works like a charm, using reference which is a nice feature, I must admit.

Here's some action on a treb that's loaded and being prepped for action, this one will be placed next to the one that's dynamic... I hope my pc will be able to get through the data of a scene which will be 4 times as heavy as this one and this one is getting rather heavy... Och well... (

07 July 2004, 12:15 AM

That looks awesome! This one is going to be the best by far!

Great job man.

07 July 2004, 12:38 AM
Your computer going to choke from calculation time or from geometry data? Your trebuchet doesn't look all that heavy so I can't imagine it could be that. Your little dudes are also low-poly and even if you have them smooth at rendertime, it still looks like it should be fine! I wouldn't sweat it unless you've got only like 512megs of ram or less. You can always render in layers as well. If it's calc time you're worried about, just remember to cache everything as you go along.

I can't view the file here at work but I'll look forward to seeing this latest update when I get home.

07 July 2004, 04:06 AM
Neat , plus now we can see the actual size of this big Treb ! Funny , but it's just about exactly the size I had pictured it , and I got that impression just by the way your ropes moved , and the speed at which the treb arm moved , so once again , way to go on getting it right !


07 July 2004, 06:00 AM
thats insane
mind letting me in on how you created those wires... do they maintain volume (i think envelope is what the feature is called? maybe not....) or do they just deform with whatever they are attached to? I know of a method (using spring/hinge constraints on rigid body's constrainted to clusters of UV's on a curve that wire deforms a cylinder) but I'm curious about yours....

thanks, keep up the sweet work!

07 July 2004, 08:53 AM
Thanks guys,

Rabbit: the dynamic data is very light, I play the animation at about 12 fps, which is not bad for a simulation this size. Polygonal data is pretty low indeed, although, you could check out one of my early wire shots and find that the rear part of the treb is pretty dense... anyway, textures is what makes it so heavy in the first place, I think one treb has about 9 textures of 1k*1k and 2k*2k, the workers too have pretty high texture resolutions, not THAT big though, but also about 9 1k textures. Still it works pretty good, by card can still work that. Then we got deformations, I got skins and 15 blendshapes on every single character, which makes a character 16 times as dense, because of the shape data of a blendshape... it takes about 21 seconds to load the scene... The scene where I'm gonna put everything in, has this HUGE ground texture, we're talking about a throw distance of 750 meters, so I need a plane at least that large. First I drew a ground texture for the entire ground on a 4k by 4k texture... but... when I render this out from the point of view of a human near the treb, I'm standing on one pixel the size of ping pong table. Then I used layered shaders to add a more detailed texture on just a portion of the ground plane of 4k*4k. The result was better, but still tere's huge pixels underneath my feet... I added another 4k by 4k texture right where I am rendering, and that works just fine... In the end, about 30 characters, 3 giant trebs, maybe some birds, some painteffects and a hell of a lot of geometry like rocks and branches... I was even planning on using fur for grass, but with finalGather that would be suicide...

Gremlin: Read through the posts in this thread, I posted that before, I used cube to cube pin chains for the wires that need to be the base for other dynamics, such as the pulley and the rock. I used dynamic curves for the other wires. (Great avatar btw)

07 July 2004, 05:51 PM
Even More Goodies.

I needed a treb that's being build... I was thinking about how they would get the huge arm and weight 12m high, to secure it there... I build a frame around the construction site and made some more wire work... then I figured, lots of people were needed to lift a thing like that... so I created 4 wires, with 4 people on a wire... it took me about 2 hours to animate the variations in the pullers... left right... then I wrote some more scripts to automate the clip importing and in the end it took me another 20 minutes to make 16 workers who were allready pulling... The scene loads in 2'40"... well here's another playblast:

The rope is a little too static I think, but hey ( (

07 July 2004, 02:04 AM
did you do the cables like this?
thats the method I know how, but when you say dynamic curve... you mean converting it to a Maya 6 hair dynamic curve yes? how are you implementing both techniques.... also, your ropes dont self collide or collide with anything else do they?

07 July 2004, 07:36 AM
Hey Derby, checked out the latest. You're crazy man! Absolutely nuts. Your guys pulling the cable is all wrong though. They would all pull together, they would have some sort of task master yelling "HEAVE!.......HEAVE!......HEAVE!" etc. I'd recommend animating one clip, then altering it slightly so there is some variation, maybe just 3 or 5 subtly different clips, then apply them to the characters so they're heaving together. This would be much more realistic. Also, you can fix the staticness of your ropes super easily. Just make the ends of the ropes softbodies with collisions. Making the actual cylinder a softbody would look whack but if you've extruded a circle along a path, then you could make the end of the path a softbody and the rope would maintain volume.

Looking good! I'm going to try to catch up some more this weekend and post some real dynamic tests. I started playing a little bit with destroying the wall a couple days ago. I will be very interested to see how you implement it in yours.

07 July 2004, 09:24 PM
Cables made up with constraints, indeed somewhat like the tut you showed, en dynamic curves are solved seperatelly, so it's prefectly possible to integrate the both. I know I should let the workers pull at the same time, I tried that, but it looks horrible, I think I would at least need 5 animations, which is 20 hours work instead of the 1.5 hours I spend on it now, in a few days the challenge is over and I don't want it to drown in my extra detail... talking about extra detail, here's my knight, 5000 polies, 2 textures, 1k and 2k...Don't like the yellow on it too much, and the shinyness might be too shiny... but when a force, which is french I noticed from the marks on the armor, can afford to take over a stupid brick wall with 3 gigantic trebs, they surely can afford to shine their armor :)...

Wanted to do a cloak as well, but that's gonna be overdone I think... Dunno, maybe it's just this one knight... then it might be possible...

07 July 2004, 08:07 AM
Some VERY fine modeling and texturing again, friend Derby-Q Salano.

*bows deeply*

Keep it up!
Good luck finishing the challenge.

07 July 2004, 10:16 AM
Thanks man... an update in the morning, now onto setup and animation, I used a very light cloth for the cloak. I feel it solves that lack of contrast...

07 July 2004, 07:43 PM

That's some fast modeling! Keep up the great job!

07 July 2004, 10:58 PM
You, my friend, are insane. :eek: I mean that in a good way, though. Talk about going above and beyond! :applause:

07 July 2004, 02:39 AM
Beautifull work there Derby, utmost respect.
I`m sure one day the school will get there as well. You`re good one your way to become one of the future well known names in the industry if you continue like this.
Although Belgium doesn`t have any professional 3d education, it sure has some very talented people :)
Maybe one day we'll work together as teachers or as artists :) - or both


- Although I really don`t have time for these challenges at the moment, I'm looking forward for the others involving dynamics.
- this will also be excellent teaching material for the advanced class ;) if you want to use it for that purpose that is.

07 July 2004, 11:51 AM
Thanks. Modeling was actually not the part that took much work, it's actually quite lowpoly, 4797 faces without the cloak.

There there Peter, you find your way to my hideout :)

Thanks for the comments all, here's a rendered frame for the final animation. Hope you guys like it, first frame took 10mins to render, at frame 50 it drops down to 5mins, in the end I will have 20 hours of rendering... jolly...

Well actually I am glad it's rendering... when I first tried to render, the renderer would crash on every try, overload... I resized the textures to 50% and optimised the meshes, the workers lost their facial differences, luckely there's not a frame where they are in closeup, now I still got crashes, so I decided to take out the third treb, the one that's being build... I modified some render settings and now I'm walking on air, I even think it would still work with the third treb active... although it was blocking the view, so I'm better off without it... Here's that render:

07 July 2004, 12:05 PM
couldnīt you also have reduced the colour ranges of the textures. i often reduce my colour maps to 256 colours rather than reducing the resolution of them. in most cases you cannot tell the difference colour wise, but reducing resolution can bite you when for some reason you need a closer shot than the texture resolution allows.

by the way your image looks fansastic. i would separate the scene in passes though and comp them back together if the rendering crashes all the time. like background, trebs and people all separated to help optimizing rendering.

I really want to see this animated.

07 July 2004, 12:09 PM
I have been thinking about passes, but I didnt want super high render times, so the crashing is more of a safety :) I never tried reducing the color range... nice hint, I'll try that some time, the reduction in resolution is acceptable, only in the first frame you see some pixels, but I'm not gonna worry about that anymore...

07 July 2004, 10:07 PM
Is the background a photo that you're comping in or is that a render as well? I can't really tell, it looks good but something is goofy about it. The trebuchets look like either the perspective is slightly wrong or they're lit differently or something. I dunno! But wow it's looking cool. If it IS a rendered background... you're not rendering every frame with the background, right? You could just do one render and then comp it back in of course, unless you have a moving camera. Anyhoo, I'll look forward to seeing it in motion once it's done.

07 July 2004, 10:35 PM
I have to say this is the coolest work i have seen at cgtalk in a long time!

awesome work man!

07 July 2004, 12:44 AM
I agree Rabbit, the skyline is a bit out of sync with the rest of the scene, but I'm not worrying about that really... I'll do some post color changes that will modify the overall look anyway.

Thanks a lot Sheep Factory, not worthy but gratefull :)

07 July 2004, 01:00 AM
OK ... this is just sickly insane work in a short amount of time. How? :argh:

I really don't have anything constructive to say at this point. I think the animation is fantastic and very true to it's scale. I also don't have enough knowledge of dynamics to understand how this achieved. I just wanted to say I'm impressed with what you've accomplished so far. I'm looking forward to seeing this thing in it's final stage.

Keep up the great work. :thumbsup:

07 July 2004, 07:26 AM
Hi Derby :

Great job of expanding the concept ! I guess I should say that at first , I guess I must have misunderstood what the mod wanted , and do apologise for any advice I gave people about concentrating on dynamics , not visuals . perhpas the mod initially may have meant "let's do some really realistic simulations" , but you have taken this whole venue to another level , totally of your own accord , and for that you should be shot ! ... Just kidding , of course <big grin> .

Seriously , I think you have demonstrated to all of us just how far one can go if they are willing to do the work to the best of their ability . You're obviously much more capable than myself , but I'm one of the lucky one's , in that I am inspired by your work , not frustrated or turned-off in any way .

I can just imagine the joy of an CGI Art Director asking you for something fairly simple , and then having you present that person with a concept or animation beyond what even they could have imagined !

Another point . that perhaps is not so insignificant (please allow me to comment) is the way you handle the "nit-pickers" , who of course are only trying to help . You respond with "oh well , I'm not going to worry about it" , and is such a great way of perhaps sharing your insights into what you think is important , and what is not . Good for you !

Well , what else can I say ? Very gratefull for having the luck to just be here and see how a skilled person has approached the challenge . Wonderfull . Hope to see your name up in lights some day , and I do hope you even eventually get to help your fellow country-persons along while you journey !

Cheers Derby !

studio (edit: misspelled Derby)

07 July 2004, 06:35 AM
Thanks a lot everyone, too kind!

I'm now rendering some shots, having trouble filming this though, if you have any ideas on how to film this, very welcome, now I focus on the trigger for 100 frames, then go to another cam standing somewhat away, who zooms out as the treb launches... then I got some flying projectile renders and then a tower gets smashed pretty hard.

I also wrote a guide of about 12 pages that'll I'll upload in a few days, about what I used, how I would advice to do that, hints and tips, stuff like that... Hope you'll appreciate it when you get it.

07 July 2004, 07:41 AM
Your work is brilliant. You surely nailed the simulation, its stunning.

07 July 2004, 11:20 AM
derbyqsalano, I hope it doesn't feel like I am just getting in line like everyone else but after reading through the six pages of this thread I have to say your work is very impressive. Working with dynamics, especially ropes, can be terribly painful at times and I admire your end result!

Thanks for sharing with everyone,


07 July 2004, 06:05 PM
Thanks a lot everyone, too kind!

I'm now rendering some shots, having trouble filming this though, if you have any ideas on how to film this, very welcome, now I focus on the trigger for 100 frames, then go to another cam standing somewhat away, who zooms out as the treb launches... then I got some flying projectile renders and then a tower gets smashed pretty hard.
If it is possible, I would set up multiple cameras and cut it all together in post. I would also set up the anim to first buid some tension, jump quick to action, maybe wane a bit, and big action to end. If you are adding audio FX you could have some beginning close-ups of the weapon in the ready position with some creakying rope audio, then a fast launch, maybe some wall damage, then your guys reloading, maybe some other trebuchets in the distance firing, and finish with a launch and destruction of a key piece of wall.

07 July 2004, 11:01 PM
A view of the castle, looking out over the field and on the trebuchet in the distance, slowly panning from left to right, passing the treb a bit and then focusing back, staying still for a millisecond and then zoooooming in on the treb, or maybe even on the eye of the treb commander.. THEN going to the treb firing-view.. that would be cool ;)

Awesome work dude, just awesome.. it has been a pleasure following this thread!

07 July 2004, 11:06 PM
Thanks, although both suggestions are a bit too late, aka too much work and August 1st I got other priorities, I've been rendering in 5 shots, trigger, launch, two shots of flying projectiles and a crumbling tower, which is still in progress, glad about the amount of response though, highly appreciated!

Derby-Q Salano

08 August 2004, 08:06 PM
Check out my final render, at least for now. I think I will add sound, I got some more time left (

08 August 2004, 12:36 AM
Holy crap, that is amazing. I'm in complete awe of just how far above and beyond you've gone in this challenge. Says boatloads about your dedication to the art. I love the little touches you've included, like the little half-stumble the trigger-man does after hitting the switch. I feel like the wall could have taken more damage, though, if only for the sake of dramatics and visual excitement. May be too late for that by now, though.

Congrats on such a fantastic entry. :bowdown:

08 August 2004, 07:43 AM
Thanks. I too wanted more damage on my tower, in fact, the dynamic part is a lot bigger then the part that gets smashed, but the animation wouldnt run, it took me a lot of time to solve the problem.

08 August 2004, 08:01 AM
This is really, really nice. Good job, man.

I agree with the above reply though, more damage would be nice. I guess it is realistic damage though, castles weren't built to be destroyed :P

08 August 2004, 08:25 AM
Superb job!


08 August 2004, 01:15 PM
Love it, really great work there. That's amazing that one person did all that work in such a short amount of time.

08 August 2004, 05:41 PM
ok.. u got me into this.. im sooo in...

hope mine looks as near as nice as yours...
15 days.. DOH!!!!

well inspiring work

08 August 2004, 10:19 AM
looks awsome but I think that the basic run you had earlier without the fancy stuff looked more impressive. Also the texturing on the castle after it "chips" looks bad.

But wow, the efford you put into this, that is the most impressive of all the submissions so far

One thing though, at 4 secs into the animation when its lifting the rock one of the objects on the trebuchet gets blurred or something for one frame. Well happens a few times, its the object holding the 4 ropes, starts to turn and goes into motion blur

08 August 2004, 12:24 PM
this is really awesome! very good job!

08 August 2004, 12:32 AM
Thanks all.

You are right, more damage would be better, but I ran out of time, now I don't have any time to work on it, so I had to finish it by August 1st. That's why the tower isn't properly finished. Well that's not the main thing of the challenge I feel, otherwise I'd have put more work in that instead of the treb.

Hexodam: I'm aware of the motion blur problems, the pulley is sometimes messed up, I know, very odd bug, was going to fix that too, but due to lack of time, that'll probably stay there.

My website is online finally, if you would like to check it out, you can visit it at


08 August 2004, 01:58 AM
nice job on the trebuchet tutorial, I found the part about the Pully very interesting. - nice site design in general.
ciao !

08 August 2004, 07:49 AM
Awesome... all i can say.

I decided to do the dynamics part of the challenge after i saw yours. Too bad your tutorial wasn't out til after i "finished", as i went through, ahem, all of the problems you addressed on the first two pages and ended up doing it just the way you did... full-scale learning effect. :)
Then again, reading your tut invalidates participation in the challenge.... Bad for everyone who already read through the tutorial. ;)

08 August 2004, 08:26 AM
Heh, well I wasn't going to post the existence of this tutorial untill the challenge was over, but since it's a rule to not imitate a tutorial, I should have written it a long time ago to keep the copycats at a distance :)

08 August 2004, 08:46 AM
That was exellent! There should had been some poor victims manning the castle walls being knocked down though, but I'm really impressed by your speed! And Modeling. And detailing and... everything! =)

08 August 2004, 12:36 PM
This work is fantastic derby!! :applause:

I really like the look of it and the whole environment. Dynamics is some kind I'm really interested in, but unfortunately I haven't got enough time to dive in :shrug:
So I've got a question for you, is it possible to get the early file (the one before or short after the rope demo) for learning?
If this will be possible (surely AFTER the contest, not now :) ) that will be very very gentle. because for me it's less timeconsuming trying to understand someone elses thought and how something is made, than following a tutorial :)

anyway, keep this work up! it's really great.

08 August 2004, 09:21 AM
:applause: WAW THIS WORKS RELY NICE!!!:buttrock:

Unfortunately I have no time to partecipate to this challange but I think that U kan add a very fine featuret to your catapult that will give to your model a longer fire range. tnx to the concept of radial velocity if U short the harm of your catapult during the lats 20degrees of rotation the rock will be much faster getting a lot more meccanic energy. Making this is quite easy using the reverse of the concept of harm extention and cuz isn't in the rules that your wepon can't be hitecknology you can easly apply the idea.
Efficency over the top;)

08 August 2004, 12:46 AM
Good suggestions, thanks for the replies, all.

Here's my final submission.

Hope you like it. ( ( (

08 August 2004, 03:19 AM
ok, i dont dare to crit, cause i cant do 10% of what u have done. But, if you dont mind....
I think the top bomb or ball, whatever it is, that they are throwing, breaks the wall before it even touches the wall. I guess ur pivot for the force is in front.. which makes it hit the wall before the ball actually hits it and thus break it.

Same goes for the second ball, the area it affects is a little "not practical". I mean, its fine, but if u want to refine it, then.. cause when it hits the wall, it first breaks the wall, then the wall seems to get back to itself, then falls apart.. i mean, i know its supposed to happen like this, but just that the area seems a bit not right.

And, its just my personal thingy... i was expecting only one ball to hit, cause i saw one Trebuchet to shoot. But its fine... =p

in total, w/o any question u have raised the whole level of the competition. really nice. i had to go wow. :thumbsup:

I hope you dont mind my comments, and i hope i am wrong.. cause its a really good work, and i dont want it to have flaws.

08 August 2004, 09:22 AM
I'll teach you a thing about dynamics, the collision isn't done by placing a force field on the projectile, it just gets bounced back if the projectile hits. So it can't hit too soon, it just hits, that's out of my hands. Maybe it's because the rock doesnt fly through... well that rock has a mass of about 100 kg, the bricks in the wall each have a mass of about a 100kg and all of m are stuck together, plus, they are positioned in a round arc, which makes a tower like that basically invinsible. So if the ball would fly through, that'd be like a superball, cause there's no way it could pass through.

Just ignore the fact that there's multiple trebuchets there, the second ball was just to put in some more action.

I don't really understand the remark, but I appreciate the help, I hope I will be able to put some more work into destruction in the next challenge :)

The problem with the pulley is solved btw, download is updated

08 August 2004, 10:13 AM
I must agree about the sudden appearance of the second projectile. It's rather strange since you don't see a second launch, but it's not impossible and certainly a good idea to add more damage.

This solution is also the only one I saw with realistic damage. As Derby-Q Salano says, the 'fortress' (it doesn't have that name for nothing) is a rather firm building and won't just collapse like the tower in, let's just say, "grau's" animation. Nor will the ball fly through without previous hits, at least, that's what I THINK.

Sure, it all adds to that 'WOW' Hollywood-drama effect. But not everybody likes that ;)

The scenery is absolutely stunning, the detail of the grass waving in the wind and the little stumble of the guy that releases the ball is overwhelming. I especially like the little dude on top of the rear trebuchet hammering away, I almost fell off my chair because so little people would notice that in a regular movie and still, this animation has it. And then there's the glimpse of the knight overlooking the entire site. Absolutely wonderful stuff if you ask me.

08 August 2004, 09:08 PM
Thanks bro...

Acid, unfortunatelly I'm not gonna be able to give you any files, but you can check my website for a complete guide on the trebuchet, at check tutorials

08 August 2004, 04:19 PM
Voting has started, check it here

08 August 2004, 04:01 PM
Awesome work! Truly, a lot of time was spent on this dude.

One crit: The scene where the rocks hit the wall. There some pretty major shadow flicker happening. Maybe some camera shake would help sell it too. Im not so sure about the flaking off of the facade--one would think that a boulder moving that fast would do more damage...

Great job though. Very beautiful!

08 August 2004, 04:09 PM
Ah nuts I forgot the camera shake, well, I didn't really like the tower, and more damage was needed to get more votes I presume, I wish I put more work into that, though I couldn't continue working on it after the 1st of August. Anyway I'm super-happy with a tie with Cory, never won anything, so I'm glad.
The flickering is caused by the crappy particles. I didn't want to spend too much time into that see...

Thanks for your reply.

08 August 2004, 02:32 PM
Been meaning to do this...

08 August 2004, 04:46 PM
Thanks Roberto, thanks a million.

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