Cinema 4D: Make A Dynamic Spline Hold Weight

hi guys it's Sam for digital meat and in this tutorial we're going to be looking at having dynamic splines hold weight now you can't actually do this with just dynamic splines it needs a little extra thing in the in the mix and I'll show you how that's done so first things first let's get a splined so we go to our spline menu we choose linear I'm going to middle click to get to my top right in front views I'm going to use the front view I just turn snapping on make sure our work plane snaps on and gridpoint snaps on this way when I create a point I can just drag it to where I want the grid points and it will just snap snap to it so as you can see down at the bottom of the position I've got my Y 100 centimeters and then the second one I'm going to put a 0 so that basically means my spline to meet along okay so let's go back to either view select tool and there's our spline and right this is going to be dynamic so it's obviously going to need segments and I've just got one so far in between these two points so we're going to need more than that so if we if we go to point mode control I select all our points right click go to subdivide and let's give it ten subdivisions now you can see there's 10 seconds to our spline now ok so that's great now obviously that spline won't render it needs a needs volume so what we can do is if I select the spline and then go up to this menu here and hold alt click on it and hold down we can go to this sweep here reason your old alt is because the spline is now automatically be made a child of the sweep if you hold out okay so now it's in the suite we need something to sweep along this path so this is acting as our path if we go back to the splines and choose circle make the radius something little bit small say 2.5 centimeters yeah that's fine and then drag our circle into the sweep we have an object with volume yeah and that will now render okay great I'm just going to change the display to crowd shading lines as you can see we've got a butt ton of subdivision there so if you go to our circle and you can see the intermediate points are adaptive if I'm gonna change that to uniform so the same distance apart and I'm also gonna see this number here and we've got eight if I drop that down it means there's less rotational segments so that's fine also for the spline I shall leave that as it is for now what I'm going to do is I'm a dump all this in a null object so I'm going to go up to here create object null and then grab my sweep and make that a child of the now the reason I've done that is if you grab the null I can move that around and everything moves with it um you'll see why that's important in a minute it's just so when my rigs inside that null my rig can be active and working but I couldn't position it where I want because it's a child of this sort of empty object so if I go to my spline let's add some dynamics I'll tell us sweep off for now and just this little tick here still there boots just off so go to our spline right-click go to the believe it's hair tags and then go all the way down to the bottom here spline dynamics now spline dynamics is on if I hit play okay dynamics obviously working be just drops now we don't want that so if we go to spline dynamics tag go to the properties tab we can see this fixed same here so if we go to point mode and select and select our top point and then go back to the dynamics tag and then set this fixed property you'll see that this is now gone a purple now if this lot wasn't in this null it would be fixed in world space but because it's a child of this null to this spline this null is it's zero if you like so as long as this fixed point in relation to ship to the null is zero that's fine but we can leave the null around as you can see there so um so this is fixed now so if we hit play you can see it's doing that just give ourselves some more time on the timeline say 30 seconds and drag this out so if I grab this now now you can see that this is moving around we got a string word dynamics on it brilliant you can also see these the actual splines a little bit you can see the segments in it so let's get that back to zero pause this go back to the beginning go to our spline and intermediate point adaptive now I want this to be uniform because if you were to make this an actual object after you've animated it and you wanted to say export it to a game engine that support vertex animation and you couldn't do that if the number of the point and the object is changing so so yeah that's that's fine we'll change this to a b-spline about two are now display and you can see that smoothed out a lot more okay so that's fine in fact what I was just saying about about the number of point is changing I think might have something to do with the sweep I sort of like checked did it I think that's okay yeah I think that's fine yeah don't think that actually changes anything okay just just have a look yeah that looks great to me I've got a cable swinging around okay right now let's add our object we want to attach to it and so let's create a box just drag that down here obviously it's way too big let's just make this twenty five seven years there we go that'll do nicely it's actually not sect in with this spline now I know that box is 25 centimeters so the pivot is slap-bang in the middle and I know after 25 is is it 12.5 so if we go in the Y direction of the box and put minus 12.5 Oh beg your pardon in here there we go it moves down and that should be is that your where we want up brilliant I should just change my display there you can actually go to this display tab up here and choose one of these or you can use these shortcuts you can see them there na NB n C and D so that's why I was using there just to flip between these okay so we've got our box that needs to be told to this a dynamic object so if we go to our cube right click go down to simulation tags rigidbody and hit play it falls away into this so for you remind that we need to attach it to our rights how do we do this right well if we go if we select our spline right click on it go back to the hair tags menu and then we have this constraint so if we select that that's great click on the constraint tag now you can see there's a field here for an object now obviously our object is going to be our cube so drag then now it wants to it's got cube and we could hit Sam but it wants to know what do we want to set this cube to what do we want to attach it to so if I just turn off this sweep again so we can see our spline select the spline now we go to us live selection tool point mode select this bottom point go back to our constraint and then hit set with this point selected it's basically saying that this point is attached to this object so let's do that okay right let's tell us we back on now they're attached great it's just what we wanted but again it gets pulled off into oblivion you notice that the box has actually come away from thee from the spline there I'll talk about that in a little while let's just get this box sorted so this spline actually can't hold a mess so like if I play this it will just stretch off into oblivion forever and ever and it will just keep going so how do we prevent that now this is the magic ingredient lets go to this view basically want me to go do is go up to the simulate tab at the top top go down to dynamics and spring I'm just dragging it to the bottom there so this spring object click on it and go to the object tab it's asking for a few things it wants object a and object B so object a will be our spline an object B will be our cube so there we go there's us if we it play now you can see that something's amiss and it's because the springs top is here and the springs bottoms there so what we're going to do is for object a the spline the center-of-mass the attachment shouldn't be the center of that it should be offset in this case we know that our spline is one meter tall so I'm gonna put 100% at me is in here so that stretches that out and for object B which is our Q it's not synchromesh we want it to be offset and the central mass is obviously the middle of this cube and like we said earlier we know that half the cubes height is 12.5 centimeters so there we go we've got us spring where it should be now there we go so if we go to a spring again come down here the rest length is 100 centimeters which is the length of the and the splines of the cable if I was to put that 200 centimeters you'd see the it back down to me is so we don't want that 100 meters 100 centimeters was correct so let's go back to the beginning with this and also you notice they actually droops down a little bit further than 100 centimeters and that's because of this value know the stiffness so if I broke this up to maybe three or maybe something higher actually yeah okay let's make that five you can see that there's a lot less bounce in it a lot less give so we'll keep that as to that for now and if I grab the nail now you can see that let me get that back to zero I can drag this thing around you'll notice that you know just give it a little bit of a little bit of movement here notice that the actual splines coming away from the box so if I can get that going again a bit better here we go mmm it's left it and the reason for that is the calculation that is being done on the box is dynamic so what typically do is I cover a zero I'll put a I'll record a keyframe for my null move it along to hide I see three seconds three point five something like that doesn't really matter leave my null across again I still got to snap it on just turn that off keyframe that go forward another few seconds I'll move that over here keyframe that go for here keyframe that and that looks a bit mad but don't worry about that you go back to zero all that animates you can see you get a little bit of slide there is slipping around a little bit and solve that way you have to do is you could actually I think is c'mon control-d get your project settings go to dynamics go to the cache and then you can bake the cache basically you're baking the dynamics but for the whole scene now if you had a complex scene a lot of things going on you may not want to do that so you could go to the cubes dynamic tag and then go to cache and then bake object bake that does it pretty quick and now play you can see that that is now sticking to that boxes center point a lot lot better because it's been more accurate about where that box actually is so there you have it you've got a dynamic spline holding a box now we can actually clear this cash so cash is yep I could actually like all this in this null actually and then I could make a copy of this so I'm just control dragging it's going to be at the same place in it yeah but they will actually react with each other so you could copy these a name and different ways having a interact of each other and you go Bob's your uncle so I hope I hope that's been useful for anyone that's been trying to get dynamic splines to hold a mass or a weight and that's how you do it technically you can't actually do it you need this spring object so thanks for watching don't forget to check out my Twitter a digital meet 3d and facebook.com forward slash digital meet 3d and my webpage digital meet you k if you're watching this on female ok cheers guys bye you

Channel: DIGITAL MEAT

Views: 58,612

Keywords: Dynamic Spline, Digitalmeat, Digital Meat, Spring Connector, Greyscale Gorilla, Animated, C4D, Rigid Body, Cinema 4D, Greyscalegorilla, Digitalmeat.uk, Weight, Animation

Id: ZDYtz6j3HAg

Length: 17min 15sec (1035 seconds)

Published: Wed Sep 30 2015