Intro to ZBrush 037 - Dynamic Simulation Menu! Easily create cloth and wrinkles on any object!

now before we get down here into micro poly let's take a quick break and we're going to discuss this dynamics menu up here so let's go ahead and close out of our brush menu and if you want to double click these little dividers over here and then you can take your dynamics menu grab that white circle and just drag it over here let's take our undo slider and slide all the way back or if you're just starting on this video go to the palette here choose plain 3d hit make polymesh3d and now we have just a basic polymesh plane in here now if we turn on the floor you're going to see with the y turned on which is on by default that's going to represent your floor plane so you can see our plane is kind of sitting upright y up on our floor plane here so let's talk a little bit about dynamic basics so by default what we have turned on is on brushed floor collision and gravity on brush is about a brush setting which we're not to yet but if we're just going to be running the simulation which is right down here with floor collision on and gravity turned on if i hit this button now it's going to simulate this plane right into the floor now you're going to see immediately all the polygons just kind of collapse on each other so if i undo that just hit control z and let's also go through here i guess it's pretty bright we can say let's add a little bit of self-collision so we turn self-collision say up to two and then run the simulation you're going to see now it kind of pushes these uh pieces of geometry apart so another thing you might notice is this gravity runs really fast so let's go ahead and slow this gravity down by taking this gravity strength and turning it down just a bit and then hitting run simulation and now you'll get a little bit of a smoother result and while we're running this let's go ahead and give it some thickness so we can see it a little bit better like we did earlier with our dynamic thickness so geometry dynamic just crank up that thickness a little bit and by default smooth subdiv is going to of 2 is going to be on and you know what let's go ahead and leave it on so now if we turn off our poly frame and let's switch back to like a mat cap gray or something we can run the simulation and now as this runs you're going to get a very nice smooth result and you're going to have dynamic thickness now if you want to stop the simulation at any time just tap in your screen or just hit run simulation again or hit escape on your keyboard or hit space bar any one of those will stop the simulation let's go ahead and get a control z and that's the basics of simulation and don't be confused that you have to run it on like perfect quads or anything like that gravity or dynamic simulation will run on anything so if i hit the comma key here go into tool and let's go ahead and grab the dog z tool and hit the comma key to get rid of that we still have our floor plane on and because we have floor collision on all these settings say the same these are all global settings by the way so we have our mesh selected here it's the only sub tool in our scene so to go through here and we have gravity turned on floor collision and we run the simulation the dog is just going to simulate gravity bam right into the floor so i'll go ahead and hit control z and that's the basics of gravity simulation now there's a lot of other things we can do with dynamic simulation but again that's kind of a good start now let's go back to our poly mesh 3d plane we're playing with and let's go ahead and increase that thickness just a bit so we can see it just a little bit better there we go now there's another way we can control this geometry and that is if we hit b t this goes to our transposed brushes we've already talked about regular transpose we even touched a little bit on smart transpose but we haven't talked about is cloth transpose so if i hit b t and then c to choose cloth transpose essentially what that did was go up here to the brush options and then underneath here there's elasticity and there's a simulation iterations any brush and zbrush that has simulation iteration turned on is going to tell zbrush hey run these simulation iterations right here at a hundred percent now you can dial this back if you want if you want to drop this to like fifty percent simulation iterations and have the brush take over a little bit more but you're gonna notice if i go to b for the brush menu and then c to narrow it down to all the brushes that start with c there's some cloth brushes in here and i'm going to choose like cloth twister and again we go back into our brush settings elasticity you're going to see simulation iterations is up at 100 which means when i use this brush it's going to pull this around and treat the geometry that it's being acted upon as if it's made out of cloth so if i undo that and go back to btc for our transpose cloth brush and you don't have to keep pressing that if you hit q to go into draw mode and then w go back into transpose it's going to choose transpose cloth until you tell it otherwise otherwise so in this case if i push this down it's going to collapse and collide with the floor and i can go through here and i can rotate this around and i can even non-uniformly scale it and have it kind of collapse in on itself and essentially what this is doing when it's running a dynamic simulation is if i undo all this and i'm going to take the smooth subdiv and turn it down to zero turn on polyframe here is it's looking at all of these edges and it's maintaining relationships it's maintaining surface area so when this moves around or collapses it's it's constantly running calculations on every movement in fact in this case it's running a hundred simulations per movement telling zbrush maintain these edge relationships so that when this thing expands or contracts or folds in on each other or collides with another object these edge relationships stay relative to each other or maintain their surface area so that it acts like cloth now there are some limitations to this so if we undo back let's go over here and let's go to append and we're just going to grab a sphere 3d so select the sphere 3d go in here and just scale this down and you're going to see when i scale it down because we have transpose cloth it's going to treat this object like it's made out of cloth so let's avoid that let's go to btr and we'll scale this down to make a little bit smaller and then alt tap your plane here and hold down shift to snap to the side and then hold down shift to rotate this 90 degrees and we'll move this up now you're going to notice if i select the the sphere and then move it up this floor plane is going to follow it if you want the floor plane to stay down where it's supposed to be or where it is originally you can hit draw and then change your elevation to zero that's going to snap that floor plane to world zero so now as i move this up and take my plane and move this above the floor plane isn't going to follow it's just going to stay down there so now that i have two objects in my scene if i go through here and i have gravity and floor collision turned on if i run the simulation it's just going to fall right through that object it has no idea it's there what i need to do is go ahead and hit control z go over here and turn on collision volume and it's going to look at every other sub tool in my scene in fact if i have multiple if i have this one and i duplicate this off and i scale this down and i move it over here so now i have two objects in my scene as long as i choose this plane and then in this case i can turn collision volume on and off or i can just hit recalculate it'll go through and recalculate my collision volume so now when i run the simulation it'll recognize that and behave accordingly and again while it's simulating zbrush is telling those edges a hundred times a second or a hundred times a movement to make sure it's maintaining those original relationships now if i have my gravity cranked up to like 40 and run the simulation it's going to get some really really bad stretching so when you come in here with the default gravity of 10 and you run a simulation you may see that it stretches pretty badly on some of these areas here there's two ways to avoid this number one you have simulation iteration set to 100. you can crank this up to a thousand and then on per movement it'll it'll calculate a thousand times a movement so now when we run the simulation at gravity strength of 10 it'll run at 10 and then it'll also drape with a lot less stretching because it's calculating so many calculations per movement that it's maintaining those relationships in that original surface area very well now there's another way you can combat this i can take the simulation iterations and choose go back to 100 and again if we run the simulation of gravity of 10 you'll get some stretching however if you just run the gravity at a lower result so maybe gravity of say like two and then run the simulation that's going to run it slow enough to give this 100 calculations enough time to maintain those relationships same thing as if i'm using btc or transpose cloth if i move it really fast you're going to get a lot of stretching if i go through here and move it slowly that'll give the simulation or the algorithm enough time to make those calculations and maintain those relationships and if i hit q to go back into draw mode and do b c k which is cloth hook i can pull slowly and that'll kind of again it'll maintain those edge relationships or i can pull very quickly and it'll allow a lot of stretching now this isn't like real life where if you have a sheet or a towel where if you pull a towel really quickly it's not going to stretch but because it's 3d and we have limitations on the number of calculations happening you can actually cause it to do unrealistic things if you move fast enough again to combat this you can crank your simulation durations up and then as you move this faster it'll go nope i'm calculating a lot so i'm going to have a better easier time maintaining those relationships or another thing you can do we'll drop this back down to 100 just go through here and just move this slower and allow enough time for those relationships to be maintained by your calculations let's go ahead and undo that there's another option in here called firmness so let's go and turn off our poly frame switch back to our start of material and let's go ahead and run gravity add this you know what we'll crank this back up to 10 to make it run faster and then we'll crank up our simulation iterations so when i run this this will be the result and you know what let's also go down here and turn on smooth subdiv of 2. so this will give us a preview of what it would look like if we had our cloth simulation run on the low-risk geo and then subdivided it twice you'll get a little bit nicer wrinkles happening through here so here it is at firmness of three let's undo that and say firmness of one and run the simulation and you can see you're going to get a very very silky cloth result so i'm going to go up here let's turn off the floor i'm going to do shift s to store a screenshot we'll undo that we'll set the firmness to 3 run the simulation again and now you can see this cloth is behaving a little bit more like a denim let's do shift s let's do firmness level of five undo that and then rerun the simulation and now you're gonna see we're getting a very leather like consistency so depending on what firmness you have selected that'll give you a very silky to a little bit more of a cottony or a denim all the way to a leather type of cloth simulation so let's hit undo one more time let's hit ctrl n to clear our canvas and if we go over here to liquify if we turn this on and we have gravity turned on and we run the simulation nothing's going to happen what liquify needs is a change in direction of your edges in order to play off of so if i go through here with my move brush and i just kind of pull some dimples into the surface area here and then i run gravity with liquify and run the simulation let's go ahead and turn our simulation iterations back down to 100 by the way and turn our firmness down to say 2. so now when this runs you're going to see it's going to look like it's kind of falling through water let's go ahead and pull this one down as well so if we just do regular gravity it waits until you see it sees a collision object in order to act on it so it'll just fall and then it'll collide and drape very much like cloth however if we turn on liquify and run you're going to see it's going to fall as if it's falling through water and in fact if we pull a little harder on this side we can kind of force the direction it's going to go in so if i run the simulation now there we go so as it falls through it's going to act like it's just an underwater sheet and it has a very much more liquid result as it's falling but remember it needs something an imperfection in the surface in order to run now while we're running that there's another interesting thing you can do you can go in here to your layers and there's a record deformation animation so if i turn that on and then i run my simulation and just let it go and then once it's done i can go ahead and stop the simulation untap record and then put this on my desktop as an animation or just name it whatever you want go ahead and save so now if i un or if i just move it'll snap back to where it was originally so what i can do here under the layers okay now import that mdd file so i can import that animation and now i have a new layer and it went ahead and opened up the timeline for me you can find that underneath movie timeline show so you can turn that on or off but it turns on by default automatically so now if you just set a point in your timeline so we'll just go ahead and tap on our timeline to set a point as we play this with this layer selected as i go past that point it's going to animate my sheet that i animated here so i can pinpoint exactly where i want to start and stop this animation so if it's like oh you know what this was perfect but then it fell off no problem all i got to do is back this up go ahead and store it here and if i like this i can go say hey bake all and now those vertex positions are going to be baked into this object and if we go back into our geometry here this is all just dynamic as well the thickness and the smoothness of it if i turn that off this is the real geometry so i can turn that on and off at will and i can even go in here to dynamic turn smooth this down to zero i can go in here to micro poly we haven't talked about micro poly yet but it's very cool i can turn this to chain mail and if we undo back to uh before we baked the layer here as i play this animation here because it's just dynamically smoothed i can literally go in here turn somewhere that's down to zero turn the micro poly to chain mail and on the fly it'll render chain mail on this cloth as it interacts but again it's just dynamic i can go through here and i can change this to change this from chain mail to a weave pattern or to tubes and again still dynamically simulate or if i don't feel like dynamically simulating i just go over here to this layer and say with it selected just say delete that layer and go back here to b c k for a cloth hook brush and i can pull this plane around and simulate it or hit btc for a transposed cloth and have it run into our collidable objects down here so it'll collide with these objects and all of this dynamic stuff i can change on the fly i can change a different micro poly to chain male here or i can turn micro poly off i can turn on smooth subdiv thickness and again as i'm colliding this with these collidable objects it's all updating on the fly

Channel: Michael Pavlovich

Views: 10,352

Keywords: ZBrush, ZBrush Intro, ZBrush tutorial, zbrush for beginners, zbrush basics, zbrush dynamic simulation, zbrush cloth, zbrush gravity, zbrush collision volume, zbrush floor collision, zbrush cloth firmness, zbrush self collision, zbrush cloth self collision, zbrush inflate geometry, zbrush pillow, zbrush cloth brushes, zbrush transpose cloth, zbrush simulation iterations, zbrush stretch cloth

Id: Eh1et-TViDI

Length: 15min 43sec (943 seconds)

Published: Fri Mar 19 2021