Cloth simulation in Cinema 4D R19

Averill today we're gonna go and take a look at cinemas cloth system now I will just preface this and say that cinemas cloth system is naturally not one of the newer features it's been around for quite a while but despite this it's still not a bad feature there are certain limitations because of the age but if you want to do some realistic blowing flags draping cloth that sort of thing there's probably not much of a better choice directly in cinema itself so let's go take a look shortly we're gonna add in a plain object this will be our cloth surface itself and here is our first limitation the cloth system will only work with objects which are editable so this plane object I can't add the cloth system to this well I could but it just wouldn't do anything so it has to be a raw polygon object so for the moment let's just make this thing editable we'll come back and have a look at some of the settings of the actual object itself a little bit later but for now let's make it editable turn it into raw polygons and the process of turning into cloth is pretty much just one tag if you go to tags simulation down in here we have the cloth tag and you may notice the icon is a little blue t-shirt which ironically is one of the few things it's not actually that good at so anyway once we've got this blue t-shirt cloth icon on our object we can press play and it will do whatever cloth does which in this case is just fall down and go nowhere so naturally we give it we need to give it a reason to stay still we need to either give it something to land on top of or we need to hold on to the cloth somewhere so that it can blow and drape in the wind so let's start off by giving it something to land on so let's pick another object we'll just go for perhaps a sphere and in this particular case you can use other objects they don't have to be made edits will let out to be polygon objects so in order for us to collide the cloth with this sphere let's place that underneath and if we press play we won't really get anything for the most part all of cinema's physics engines you need to tell an object it should be part of it so for cloth to collide with an object we have to make it part of the cloth physics system so let's pause and rewind this and just tell us sphere down here you under tanks you should be a cloth Collider now once this is added to the object cinema now knows our you should interact with the cloth so when we press play it'll fall down and hopefully land on top of the object so this is sort of like the basic setup nominate one object to be cloth nominate another object to collide with cloth and you can now get the physics between the two so let's just extend our project a little bit longer let's say maybe 200 frames rather than just 3 seconds of animation and let's start solving some of the biggest issues we can see with this so the first thing is that it is very clearly very faceted there's lots of horrible harsh polygons on this object now there are a couple of ways of dealing with this I'll give you the quick short version and then we'll deal with the proper way of fixing this a little bit later but the quick short version is just chuck it inside the subdivision object this will give you generally the best quality the smoothest finish so here's my cloth this is the plain just chuck it inside and in all those horrible polygons are now smooth enough so that improves the quality quite noticeably and the other big issue we generally have here is the overlapping now as this cloth falls down it falls down from the sky lands on the object and you can immediately see these big pieces here overlapping we have a couple of ways of going about this one is fast but completely hit miss and the other method is more reliable but it will slow the simulation down so the quick fix is to choose your little t-shirt cloth Ike on the plane let's pause this and come down here what you'll find is we have a number of tags we'll go through pretty much all of this but just for now your two choices are under forces there is something called self repulsion that's what you do when you're a bit emo and you don't like how you look in the mirror what this does is it's not collision detection all it does is it sort of a best analogy for this is it's like taking two magnets of the same polarity when they try and push together when they get closer and closer they'll get closer and then they'll push and push and they don't want to detach but they'll push each other away but there's no guarantee that those magnets wouldn't have a touch and in the same way there's no guarantee that the cloth won't ever intersect itself it just usually dramatically reduces the chances with that said it does sometimes just go completely wrong and make everything worse so at the minute when this thing falls down it falls down onto the sphere it immediately overlaps so if we try a little bit of self repulsion MIMO button let's try again falls down and yeah okay fine in this particular case it just hasn't helped at all sometimes it does work it's the one I would go for first because there's very little computational overhead but it doesn't always work unfortunately so your other choice let's forget that your other choice is considered an expert setting mmm we're experts now and it's just simply called self collision let's turn it on let's rewind let's press play usually slows the simulation down quite a bit your frame rate will drop so we've solved that that's that's not colliding that's that's good but we do still have the neighbor over to the side now we'll probably deal with this a little bit later but if you just wanted to sort of quickly improve very generally the quality of your cloth simulation self collision is the quickest simplest way of doing it so we'll we'll improve this a little bit later but first let's get some of the more basic settings done and out like okay so taking this as our starting point let's go to the tag let's have a look at our settings and see what we've got so stiffness flex Ian and rubba now in here these these three settings probably helps to give you a little bit of background as to how the cloth system works if I show you the wireframe mesh here's our polygon so what we basically have the cloth system is a series of Springs so just imagine a really cheap sort of a Boy Scouts Girl Guide summer camp camp bed the kind where it's just sort of a series of Springs spread out in this sort of grid with a mattress sat on top of it that's kind of how cinemas cloth system works so in reality from this point here to this point here there is a spring running across and there is also a spring running across from here to here so in short from every polygon to the next one horizontally vertically diagonally there's a series of Springs and that's what these flexi and rubber settings do they're basically determining how stiff how strong those Springs are so I'll just sort of boil us down to a simplified version stiffness is how close to the original shape should the cloth try to remain and that's generally quite an important one because if you don't have stiffness what happens is the cloth will just stretch and stretch and stretch it'll sort of almost melts into a goo so you do generally leave the stiffness up really really high usually up at a hundred percent this is not really how stiff the cloth is in the sort of normal the normal way you'd say it to a normal person this is just sort of does this does the cloth stretch or not flex Ian and this is where some of the the words used to describe these settings maybe weren't the best but flex ian is how rubbery the cloth is so I totally let me just show you some of these sort of in action so first let's go back to the stiffness for a second let's hit play so the cloth falls down it lands on top and it pretty much stays out but if we don't have any stiffness the cloth will sort of stretch and deform let me lose these flexi in settings as well there we go so without stiffness the cloth can basically just sort of melt and stretch and deform and it all goes horribly wrong so stiffness is should the cloth keep the original dimensions maybe that's the best way of putting it and who put that back up to full and rewind the cloth now pretty much stays the same dimensions of cloth was originally designed for flex ian is really how rubbery the cloth is so think of something like a sort of dry wetsuit or a sort of rubber sheet the more flexing we have the more rubbery the cloth will become so if I bump this up to maybe 50% and the cloth falls down it'll sort of bounce and wiggled and jiggle and flop around quite a bit and if I bump it up even higher it's just a really rubbery sheet so this makes the cloth less cloth like and more sort of oil petroleum rubber based instead which is only confusing because there is another setting underneath actually called rubber and to be honest this is how stretchy the cloth can get so let's turn this back down to the default so if we bump up the rubber this is how far the stretch this is how far the cloth can stretch so if I say 50% and rewind is that I have to show so it's it's gotten a bit longer stretch to be this let's go for a hundred there we go so hundreds a little bit silly let's knock it down to maybe 90 but this is sort of how far the cloth can stretch so it allows it it allows it to sort of elongate than its original shape is now long story short what should you generally use for realistic cloth my advice is leave stiffness up a hundred percent otherwise your cloth will melt and then just set the others down at zero that is generally the most realistic loose soft silk like cloth simulation a little bit of flex Ian will give more structure to it it'll sort of give it a little bit more bounce so maybe put a little bit of flex in it but generally I'd leave these two down pretty low and that's going to be really your best bet as far as a cloth seam goes if you want it to be even more silky and fluid and flowing your best bet is actually adding more polygons to the original object the return of this subdivision for a moment and rewind cloth can only bend as much as the original structure allows it to that is to say if you've got big chunky polygons in your structure then you can only have sort of quite large round curvaceous curves on your object the more you subdivide this original plane object the more fluid and silky the motion of the cloth will be but the natural downside of this is that the more polygons you have the more processing there is for the simulation and therefore the slower it gets so for a fast simulation you want a low polygon object for a silky smooth simulation you need lots of polygons so do consider adding more polygons to your original object at the very start of the process you can add them now and that should generally be fine but yeah it will slow the simulation down quite a bit if I if I hit play we get a pretty good framerate when you know we're holding a good 30 frames per second here but if I rewind and I divide up the polygons on this mesh so I'm just gonna choose subdivide this will give me a more fluid motion but keep in mind that command the subdivide command this has now increased how many polygons I have four fold so that does mean there's now four times as much work for the simulation to do so when I press play on this you can immediately hopefully see there that my framerate is much worse than it was when I started I've maybe got sort of 1015 frames per second it's gotten a lot worse but it will now at least flow and give me a lot of small sort of fluids nice undulating shapes within my clothes system so that's that's just a price you're gonna have to pay for a better simulation anyway let's go back let's undo the subdivision and hopefully this still works yeah good okay let's carry on there so going down now bounce is a bit of a silly setting this is just literally how much bounce and rebound does the cost system have and look let's just be honest with each other who wants bouncy cloth probably no one thirty percent bounce you might think well that's that's still a reasonable amount but I don't really see the cloth bouncing you've got to consider something the cloth has a bounce setting and on our sphere we gave it that cloth Collider tag that also has a bounce setting and long story short they multiply so although the cloth might be 30% bouncy which is quite a bouncing bit of cloth it's colliding with something which is 20% bouncy 20% of 30% is only six so overall once you've considered both settings my cloth is only 6% bouncy that's really why it doesn't particularly seem to bounce very much so with that said you probably don't really want to ever really play around with a bounce it's already pretty much nothing and bouncy cloth just doesn't look realistic so leave that on well alone friction how much grip does the cloth have now in terms of maths this is the same as before my cloth has 70 percent friction which is basically just how much grip there is and my collider has 20% friction so 20 percent multiplied with 70 percent is 14 percent so that again is not that much friction so I tell you what let's move this sphere off to the side oops resized it let's move the sphere off to the side slightly so at the minute my cloth falls down and it fairly quickly slides off to the side it falls off the sphere especially if I push it over a bit further to the side so basically there's not that much grip it's quite happy to just slide around all over the surface those back are nothing to help so if you wanted to grip and stay on there basically turn up the friction but do keep in mind the lowest value we have right now is actually on the collision object this has only got 20% friction so I'll just crank that up to hundreds it will now stay on the object quite a bit more there'll be a lot more grip keep mind there's no such thing as a hundred percent perfect grip in the cinemas cloth system even if you turn these things all up to full it will still slide so you can only go up to hundred that's pretty much your limit if that's not enough tough I never said cinemas class system was amazing okay so there's our friction what else we got mass not too useful mass is really just how heavy an object is and you might think quite rightly so Oh surely a heavy object will behave differently from a light bit of cloth and no not really mass is just how much weight cloth has when it hits another piece of cloth so if I have a mass of one it falls down it drapes it behaves normally if I have a mass of a thousand it falls down it drapes it does the exact same thing there is no difference this will only determine let's say I've got a piece of cloth over here with a mass of 1 and I've got a piece of cloth here with a mass of 10 when these two pieces of cloth collide the cloth with a mass of 10 would push the lighter piece of cloth out the way so it'd be like throwing some lever at some paper you know the leather is just gonna smash the paper out of the way so yeah that's that's all the mess really does but given throwing cloth at cloth is probably not the most common thing you're not really going to notice this thing doing much at all sighs again I'm just going to skip over it cuz it's not a massively useful setting size just lets you quickly resize the size of the cloth so keep in mind before when I told you that cloth is really just a series of Springs the size setting is how long the springs are so let's zoom out for a second and rewind so here's my cloth this is how big I told cinema the cloth should be and when I press play it falls down however if I tell cinema the cloth should be twice as big two-hundred percent size as soon as I press play the first thing cinema does is go spraying the cloth gets bigger it suddenly expands because I've told all the springs you should be twice as long as you currently are and I can go mad I could say oh five hundred percents and now the cloth will be it'll get a bit paid off when you first start but it'll soon expand five times larger so you can probably see immediately this is not a particularly useful setting with that with that in mind do consider whenever I tell you a setting in cinema is useless what I mean is you probably don't want to use it very often now I can think of no general use for suddenly telling your cloth it should be five times bigger however if you want to make an interesting bit of motion graphics if you just want to make a nice swirly nonspecific sort of physics moving shape animate it hey mate maybe tell your cloth at one point hey you should be 50% size hit the keyframe button a few seconds later maybe make it something get bigger and it can drape over and then maybe keyframe you're getting small again in or suddenly shrink wrap around the object it fell around so you know you can't use these things for sort of interesting weird things but it's not it's just not a particularly useful setting for just actual realistic cloth Sims so anyway now the last setting in here is called tear I will come back to this because I need to show you something else before this will work but just in short for the time being tear is the ability to tear cloth if you pull it hard enough you can actually rip and shred your cloth system so we'll come back to it because right now if I turn this thing on it won't work because I still need to show you something else because certain things have to happen in certain order anyway that will do our general sort of properties for now let's move over to our next page and have a look at forces and this will be a fairly quick one don't waste your time with them again keep in mind cloth is a very old bit of cinema's architecture and when it was first made in order for you to have gravity and air resistance and wind and turbulence blowing through this blowing through the cloth you have to come into these settings and type in your values well since it was originally made you can now actually use cinemas particle modifiers so if you want to blow your cloth with some wind it's far easier to just grab a wind object place it where you want rotate into the direction it should face and instead of strength so it blows the wind and that's far far easier than trying to come down here and say right how much wind do we have in the x-direction how much wind do we have in the y-direction that's not a very fun way of trying to define the wind so I would pretty much ignore everything in here just forget it exists and just use cinemas particle effects prob about the only thing I would consider in here is just the fact that there is by default gravity so you can use cinemas particle grav gravity it won't be any different from the one you've got here so just out of sheer laziness I would tend to just leave this gravity setting in here again keep in mind you can if you feel like it suddenly turn the gravity off now cinema will just throw the cloth through space slowly spinning no gravity you'll just have fly around and do its thing so if you're trying to do perhaps some sort of underwater scene maybe you're trying to do some educational video saying all stop throwing plastic shopping bags into the ocean you're killing all the animals and you just want it's nice slow swirling undulating plastic bag that would work quite nicely for that just sort of swirling underwater not particularly falling down just floating floating along anyway you can all row settings they're not micelle useful so let's jump on over to dresser now with some of this terminology keep in mind the cloth system was officially designed for putting clothing on characters truth is it's really barely up to that task you could just about put a very loose-fitting bit of cloth onto a character but just so you know what to realistically expect cinemas clothing system goes wrong whenever you take cloth and you scrunch it up the problem that gives you is that as soon as your character puts their arm down all of the cloth underneath your armpits suddenly gets scrunched up and the realistic result you get is that the cost system just explodes and the cloth goes everywhere so that's why I say cinemas cloth system is quite good for blowing a flag draping some cloth putting some cloth over an object it's hardly up to the task of actually clothing a character it's doable and it's possible you've just got to be super super careful and have very low expectations of cinema's cloth so we have our dress a tab with dress o matic and seams another sort of clothing related terminology let me talk you through the bit sure I sure you don't want though so the first thing let's I tell you what let's get a fresh bit of cloth because I've probably put all sorts of weird settings on this let's add a plane let's put it over there make editable and give it a cloth tag let's divide it up again okay so here's our fresh bit of cloth without any weird settings on there and let's turn their divisions off okay so on your cloth settings under dresser the first thing you've got is relax the relax button allows you to essentially set an initial position for your cloth so when your model your cloth it will almost certainly be this flat polygon object but what if you want your animation to start with the cloth already draped over an object well we can relax it let's pause and rewind when you press relax it will play ten frames of animation so relax 400 three four five six seven eight nine ten relax one two three four five six seven eight nine ten well press it maybe once or twice more relax relax relax okay there we go so I think this is a fairly reasonable starting pose for my cloth system so once you've relaxed it into place for where you'd like the cloth to begin you can tell the cloth system hey from now on start in this pose and this is the initial state button so we can set the initial state for the cloth simulation by just hitting the button next to it that says set and that's it we're done so you notice all those little crosses disappear those crosses were just there to let you know hey this hasn't been saved or we're sort of in the dressing mode adjusting the start position but the initial State button sets how it should begin so the other generally useful beat we've got in here is to fix points I will just mention the dress o matic just because it's an interesting sounding button and you're probably thinking Oh tell us about that tell us about that dress o matic is a tool for taking cloth and shrink-wrapping it to a surface so the idea is you can draw a really big loose piece of cloth wrap it around your character and then press the dress o matic button and it will sort of go and pull and shrink wrap the cloth but as I say cinemas coffees hardly suitable for doing clothing on characters which makes the dress somatic not the most useful thing you could ever possibly use so I'll largely skip over it I think yeah let's keep over that right what I do want to show you though is fixed points with your cloth system let's undo a few steps and put it back up there one thing you probably will want to do with cloth is attach it to something if you're making a flag you need to pin the the cloth to a flagpole if you're putting washing on a washing line blowing in the winds you'll actually want to attach it to the washing line or even if you're putting a cape on a character you'll want to attach it to the shoulders or if you're being brave and you want to put some trousers on a character you're gonna want to attach the trousers to the waist otherwise the trousers were just sort of slide straight down so we have a couple of ways of doing this it depends how fancy you want to get I'll show you the quick knees away first and then I'll show you the slightly more impressive way so the easiest way is fixed points what we do with this is we select some points on the original cloth model that we want to basically pin and fix in place so let's say I want to take my cloth and I want to pin it down here and here in the corners so I'm just gonna I'm just gonna select some points so we'll go one two and there may be sort of three four and five so I've got sort of five points along here selected that I want to on a pin in place and it's nice and easy you just go to your cloth tag go down to dresser and where it says fix points hit set what you should notice is that these orange points when I click this they will turn purple and a purple point is a fixed point so when I press play it is now set and fixed into place over there so we now have some nice cloth draping down attached to a rod or a curtain rail and it'll happily drape down on to our model okay quite nice so where as I said though there is another choice the problem we've got with this is it's incredibly difficult for me to move these points if I select the points and I move them around it doesn't it doesn't do anything they just ping but don't straight back into place because the cloth system has sort of taken over control it's now in charge of where the points are so when I don't try and move them it just doesn't really do anything you can work around this with sort of scripting and expresso but that's not a very fun way of doing it so let me show you the alternative so I'm going to pause this and rewind and these purple fixed points I made I'm going to clear them not guilty the other choice you've got is a belt tag now the belt tag was designed for basically trousers because trousers keep falling down when you try and attach them to a character so you can apply belt and it'll keep them in place so for us to do this we need another bit of geometry and I'm just gonna make it editable just so that in case cinema doesn't like it being not adjustable essentially the cloth system prefers editable objects let's put it that way so let's do that and what I'm going to do is I'm going to position this cylinder let's just give it a different material so it's easier to see I'm gonna position the cylinder over to the side I'll spin it around and I'll just stretch it a bit longer so I've basically got a sort of curtain rod curtain rail a washing line running across by the butter cloth and normally you would put this as close as you can so it's attached but I'm gonna leave a bit of space just because I want to show you what it does but for this go back to your cloth surface your cloth object sorry and under tags where we found the cloth one there is another one called cloth belt with a little icon of a belt buckle put this onto the cloth object what you'll find is it's only when you've got a couple of settings one is the same sort of set and clear buttons we saw a minute ago and the other one is asking us what it should be attached to so I'm going to tell this plain of cloth the belt should be so drag and drop it should be attached to this cylinder and so long as I've got some points still selected I should so have those five same points selected from earlier I can now press the set button and there we go so it's drawing these five yellow lines which is basically just a visual indication that this is attached to this particular object so when I press play now it falls down and at this point we have pretty much the exact same animation as when we just fix them but the difference the advantage is that I can select my cylinder and I'll to give yourself a little bit more space here for doing an animation so let's extend it and rewind I am free to move this around so I can move my curtain rail I can rotate it around as rewind I could even scale it so here's here's one last bit of advice if you're ever trying to do an animation of a curtain opening and closing we're sort of crumples up which stretches out belt it to a rod and then just animate the rod resizing because that will crumple up your curtain or stretch it out so that's quite a nice way of sort of a stretching or crumpling something up just keyframe and animate the thing which it's attached to with a belt anyway they go that's that cinema's belt belt at its er go back to our cloth and see what other settings we've got so we skip over the rest of those not not hugely important let's go to cache so this can potentially be slow cinema might need a lot of processing power to run the cloth simulation if that's the case or there's other reasons for doing this maybe you're going to send it to a render farm you just want to make sure that it's cloth these precalculate so each of your any machines doesn't maybe come out with a different physics simulation or maybe hey this sphere I've got thing down there maybe let's just don't do a few steps cuz I've messed up my current rod there a bit so here's my curtain rod maybe I like this animation but I need to get rid of sphere what you can do is you can sort of bank and cash the physics simulation so on the cloth tag rewind just say calculate cash boo boo boo doo doo doo to do and done right no go it's calculated so it takes five Meg's of RAM not much but this is now a fully baked simulation so the first advantage is I can scrub through the simulation which you can't normally do I could actually get rid of the thing it collides with and it will still have the same physics there's another advantage but as I say this is quite good if you're going to be rendering over a network over render farm because you really need to cache your physics simulations for safety and the usual settings you can load the data save the data empty the cache so it's just sort of a regular full simulation again and here's an interesting the update frame if during your simulation you notice some part of this goes wrong you can fix it manually you can actually go to your plane updates the position of whatever point or polygon is the problematic one and you can sort of update the frame to sort of save it back in now I need to show you about disabling in the cost system because as you notice here when I move this point as soon as I let go but doing it goes back again so you do actually have to turn the cloth system off if you go back to this tag tab turn off the automatic system and that pretty much turns a cross system off but then you can update the frame in the cache again it's not something I've ever particularly needed to do but you can update it if you need to just fix a little error with the point okay last page over here then our expert settings so I've already shown you self collision that's kind of the big important one other things we've got we've got subsampling so with any physics system in cinema what you'll get is a cinema will update the physics on each frame or depending on the physics system and the default settings it will update several times per frame so for example with the cloth system we have subsampling of three which means every frame of animation this cloth system is moving it will update it a certain number of times in between so if an object is here on frame one and here on frame two it has actually calculated it several times in between those two frames so if you're finding your cloth system goes a little bit mad and the most likely cause of this is very fast movement if you have very high speed objects hitting the cloth it's possible at his you know here's your cloth surface on one frame you're colliding object could be here but then on the next frame it's moving so fast that it's actually gone all the way beyond it and it's now sitting on the other side it's possible that the cloth system won't see the collision because there was no collision it went frame one frame to frame three frame four and at no point did it hit it subsampling is how many checks it does from one frame to the next so if things are going wrong and more subsampling but again do keep in mind you will get worse processing time so the frame rate will drop and the other thing you can notice is the behavior will change so whilst the cloth with the setting of three might gently fall down and drape onto an object with more subsampling you might notice the cloth certainly goes there and it just very quickly falls down it does almost sort of change the speed of the calculation but if you've got fast-moving stuff you have to turn this thing up let's skip over that that's not very fun it never really helps and let's go down to these EPS not really sure what it stands for it could be Epsilon I'm gonna have to google that one but what it does is these are your collision margins so let's undo a few steps let's put our sphere back in let's lose the cache on the physics sim and let's get close so I'm gonna press play and the cloth falls down but here's the thing the cloth isn't actually touching the object if I put that texture on there I'm just going to turn off the smoothing because this will sort of give you a false impression these polygons do not touch the sphere there is always a slight gap now it's very very difficult for me to show this but trust me there is a slight gap in between the cloth and the sphere we have sitting underneath and that's what the EPS is how much of a gap does it leave now this is okay if you take a default plane in a default sphere and drop one on the other because these things are four meters wide they're huge but if you're doing something to scale and you're actually going to get close suddenly noticing a one and a half centimeter gap about half an inch for the Americans you're going to notice a half inch gap from one surface to another so you might need to turn this down but the lower it gets the more chance there is that one object will just poke through and stick through the other objects so swings and roundabouts choose your poison you know but these EPS values are quite high by default so maybe just sort of half of them quarter them turn them down them turn them down a bit right as for the basic cloth system that we'll do there is still one or two more bits I want to show you some advice some hints and one or two other objects so just before we leave this cloth tag I want to show you how to do a very basic thing which you can't do unless you know the secret wanna know what the thing is here's my cloth let's let's lose the belts let's lose the cylinder let's just go with a bit of cloth falling on sphere so it falls down lands good okay here's the here's the question how do I move the cloth move tool nope can't move it cinema's cloth system sets up this initial State remember when we were we were playing around with the the relaxed setting and we were saying ah this is the initial position that sets it in stone it is absolutely hard set you cannot move this cloth you've got to jump through a little hoop if you decide off this cloth should be somewhere else so in order for us to move it we've got to turn the cloth system off and we do this under the very basic tab now there's very few reasons to ever really go here except for this one single check box but what we have to do is disable the cloth system I am now free to move the cloth around wherever I like but we can't just turn it back on again because if we do this it just jump straight back where it was before so what we're going to do is turn the cloth system off position the object way we want it to actually be and reinitialize the first state so go to dresser set the initial state for the cloth and then turn the cloth system back on now when I press play it will stay where it is and fall down from that position so in short turn the cloth off make your adjustments and then reinitialize the initial state for the cloth and then finally you can turn the cloth system back on it's a bit annoying I will admit but tough that's how it works okay so that will largely do for the cloth system what I want to show you sort of last of all is underneath simulate we have a cloth menu and in here you will find cloth surface now this is pretty much 99% the same as a subdivision surface subdivision surface for the uninitiated let's just hype this subdivision surface is a smoothing tool so when you have this sort of horrible polygon eyes faceted surface you can turn on a subdivision surface to smoothen it brilliant however it suffers from two limitations the first limitation is that this subdivision let's zoom in here it always slightly shrinks the object so here's my actual cloth here's the smooth version it always gets very slightly smaller which if you have cloth sitting on an object and that cloth of all of a sudden gets slightly smaller this object it was sitting on will very very often just poke through the underlying surface so that's the first big problem this thing has fact let's see if I can make it do it let's grab a cube let's put the cube down here put it pointy side up and pop it down there just need to give it a cloth colliding tag so when I press play with this it falls down and you can see at the minute it's okay the cloth lands on it it stays still I don't have any penetration issues but if I subdivide the cloth and I smoothen it you'll see all of a sudden ooh it pokes through here it pokes through in the corner it's just unfortunate but don't worry we have the cloth surface that's why it was made so cloth surface gives us a few abilities and the first ability is well the first ability is really just a behavior the cloth surface uses a slightly different algorithm of the subdivision surface which doesn't shrink the cloth so if I replace my should show you the wireframe here so if I replace my subdivision with a cloth surface so basically just put your cloth not in here but instead in here it doesn't shrink so that's the first big advantage it doesn't shrink the cloth down there is a slight downside with this by the way in that it gives a slightly worse quality so I would say where possible use the subdivision surface because it gives you a nice smooth finish but where you need to use the cloth surface you will still get a few jagged edges keep mind you can turn up how many subdivisions it has but it will still be a little bit sort of a little bit bobbly and a little bit lumpy it's just unfortunately how layout how the algorithm works subdivisions give smoother finishes cloth surfaces they don't shrink but they'll be slightly wobbly anyway bottom eight consider use both maybe subdivide it with a cloth and then put that inside your subdivision and it was smoothing off that's what I'll wear often do use both okay so that's one thing it does the other thing it does is it has thickness so you may have noticed up until now all of our cloth it's absolutely razor thin oh no how do we a thickness we can't have thickness on the original cloth because if you try and do that then one side of your cloth will just penetrate through the other side of the cloth you you'll never keep these two cloth surfaces individual from each other they will go through so what you do is you put the thickness on afterwards with the cloth surface so down here thickness just turn on there we go we now have an edge and a bit of thickness to the cloth here's another time we're using the subdivision also works very well because I can put that inside subdivision and that horrible harsh crisp edge is now a much smoother nicer edge so use a bit of both use use both of their advantages right so onto the final thing unless I suddenly think of anything else tearing tearing requires the cloth surface so before when I was looking let's just lose these green objects for a second back on our cloth tag under the tag settings the very last thing in here was use tear and when I press play if I enable tearing it generally doesn't work of that well it sort of breaks and it tears but you get this weird big stretchy giant horrible mess and this is just simply because the the tearing system requires a cloth surface object so if I put my plane inside a cloth surface I'll just forget that subsurface Subdivision object for a second this will now look decent it will tear and it'll fall down into lots of nice little shreds so it's just short on the animation so the cloth falls it hits the sharp edge and it rips it tears apart but if I don't have this cloth surface the tearing just makes this horrible big mess it sort of works but it just makes a giant mess you have to have a cloth surface for this to work so that's it's sort of final use let me just mention how you control the tearing because by default objects will always just shred themselves to pieces at the slightest the slightest collision think back right back to the start remember I said all of this cloth is a series of Springs from one polygon to the next you have a spring connecting them and sort of putting tension on when that spring stretches past a certain point it tears it breaks and then you will get a rip in the cloth that is what the tear setting is the tear setting is how far does the spring have to stretch before it gives in buckles and stops connecting which 120 percent means you you can only take your spring which is say this long and stretch it 20% to this long anything more than that and it rips and then it just suddenly shreds that is why the cloths easily so readily just shreds itself to pieces and collapses so this is really a threshold the high the threshold gets the stronger the cloth is the lower it gets the more easily trips so if I go down to maybe 110 this cloth will rip even more easily than it did before but if I go higher let's say 150 there we go this is a much stronger much more rigid structurally sound cloth so play around with this value in here and just get the value right turnout first more strength to turn it down for for weakness and the very very very final thing I will mention for a cinema's cloth system is the Maps not sure if you ever looked into them before but these are vertex map drop boxes so maybe maybe I want my cloth to be strong in one area and weak in another or just looking at other potential uses for it maybe I want my cloth to be stiff in one area and loose in another for this we need a vertex map and I'm not going to get into all the depth of doing a vertex map I'll just give you the really short version of this let's rewind let's turn off the cloth thickness object for a moment you can paint influence onto your object so the really short version is choose the polygon object go to point mode and grab your live selection tool from the main toolbar there are other tools for doing this if you have cinemas character animation tools but I'm not covering those today so for now grab your life selection tool and down here you might be thinking oh isn't this just the tool you use for selecting points and yet it is but it has some other interesting abilities which often go on go on looked over looked and one of these is vertex painting mode so with the live selection tool down here we are in normal mode or it really should be called something like regular or standard it's nothing to do with the surface normals change this switch this to vertex painting mode and what you will get now is the same I'll brush but as soon as you click it turns red you now have a paintbrush which blends between yellow and red yellow is full strength red is no strength so what we could do with this for example in terms of cloth is paint stiff parts of the cloth or loose parts of the cloth or for the tearing we could paint strong parts of the cloth where we where it won't rip and weak parts of the cloth where it will rip so perhaps I want my cloth to rip straight down the middle I could paint all of this bright yellow so this is full strength and I'll also paint this bit over here full yellow and down here you've got your brush strength so if I get a slightly smaller brush and I reduce the strength so I'll have some 75% strong cloth here some fifths some 50% strong cloth here 25 here and I'll leave this down at zero so strong cloth medium strength cloth really weak cloth and when we do this painting it makes this tack this little gradient this is our vertex map if I click on here I can give it a name we'll call this a tearing vertex map tearing v map and our back in my cloth I can say for the tearing use this vertex map so what you will see is probably as soon as I press play this red area will almost certainly rip instantaneously because it has no strength so let's press play and see what we get don't forget to turn on the cloth surface otherwise it doesn't work in fact actually this is all far too weak so let me just turn up the strength of my cloth let's go to hundred percent strength okay three hundred percent strength let's keep going five hundred so I've probably painted these things too weak but you can hopefully see that along this bit here where I painted this vertex map we get to choose how strong that cloth is so when it falls down those bits are far too weak so they just rip soon as the air hits them but I can now sort of rip this strategically down the middle and you can choreograph where your cloth will rip right I think that is enough for now if you do have any questions on the cloth system ask me down below in the comments and I'll do my best to answer once again this is mash from a 3d fluff I hope you enjoyed these videos if you want to see some more have a look at some of my work go visit 3d fluff con that will be make if you'd like to have a look at some benchmarks I have another website see B scores calm for Cinebench results as ever go look at my friends nose man Athanasius channel i'll link that at the end here but until the next video I hope that's been useful and goodbye if you're in the UK I can offer you in person cinema 4d training or if you're anywhere else around the world we can do the same thing over Skype just contact me on 3d fluff comm and I'll get back to you

Channel: 3DFluff

Views: 27,797

Keywords: cinema 4d, c4d, maxon, 3d fluff, gsg, greyscale gorilla, cineversity, digital meat, nose man, mash, tutorial, training, guide, lesson, how to, mograph, matthew oneill, brograph, eyedesyn, cloth, leather, physics, soft body, simulation, clothilde

Id: 5oWMFGOWyZQ

Length: 55min 1sec (3301 seconds)

Published: Wed May 09 2018

Reddit Comments

[u/3dfluff]

This week I figured I'd unveil a new cloth tutorial. For just under an hour I'll walk you through how to use most of the tools, things to watch out for and show you how to get better results.

[u/DGAesth]

Thank you for sharing. Learned a thing or two there!