In this live presentation from the Association of Medical Illustrators 2015 Conference, Thomas Brown of Vessel Studios demonstrates several quick but essential techniques for medical illustration in Cinema 4D. You’ll see how the Collision Deformer, Tension Tag, Metaballs and Falloff can be used to accomplish common tasks in medical illustration. You’ll also see how Subsurface Scattering is used to achieve a wet membranous look.
|00:38||Capillary vessel embedded in tissue (Collision Deformer)|
|08:33||Dynamically texture deformations with the Tension Tag|
|14:37||Cells from a membrane with Source Falloff|
|26:38||Creating a gimbal|
|30:52||Cells from a membrane with Metaballs|
Capillary vessel embedded in tissue (Collision Deformer)I'm going to show you guys kind of the simple setup for getting those capillaries on those big blobs of tissue. And we're going to do that using the-- where are you? "Collision deformer." And this is a super powerful little guy, gets overlooked a lot and it's great for modeling and animation. So I'm going to make a sphere. We'll do a "icosa" and make this guy bigger, and subdivide it quite a bit. And then we want to set up the vessel on here and you can do this in a lot of ways. I'm going to do a free hand. And we're going to project this onto the sphere. Actually when I use "project" with a spline a lot of times I'll just stay in this viewport. I don't want to go to one of 2D viewports. And actually there's something I need to do first. If I start drawing a spline here and stop, you'll see you can't see it, it's actually placing, placing it in the middle of my scene which is not where I want it. So I'm going to go ahead and move this sphere back a little bit. Grab the free hand spline and we'll just do like a nice tortualis spline path across here. Now, I can right click and go down to "Project" and over here I'd want to do the view mode. So I just project straight back onto this sphere and click "Apply." And when I do that, you'll see the spline is now laying nicely on the sphere, which is cool. It's what we need. And now we're going to make a simple vessel out of this. So actually I'm going to reduce the radius of my sphere a little bit. I'm going to use a sweep, simple sweep to make this vessel. Drop the circle in first and then the spline and then reduce the size of the circle. So this is a good moment to just talk about file optimization, good file building practices, modeling practices. Way too many polys here for what we're doing and also the distribution of them is a little weird. I often and recommend others to change their spline intermediate points from "Adaptive" to "Uniform" is what I like to do. So I'll do that for both of these. And then we can adjust the intermediate point number and get some pretty even quads. So let's do that to both splines. And it looks pretty good. You could also change the-- since we drew this path of the vessel by hand, we can change the spline type and maybe get a shape you like a little better. So "Cubix" is pretty nice, we'll switch it to that, sometimes nice. Maybe this spline might be okay. We'll stick with "Bezier" for now. That will be fine. All right, so this is the cool part. I'm going to go ahead and really up the segments on this. I can put it in a null but just to kind of proof of concept, I'm going to do this way. Crank up the segments and I'm going to put the "collision deformer" below the sphere because that's what we want to deform and sort of embed the vessel around it. So the "collision deformer" needs a reference point. It's need to know what is going to collide with the sphere. So if we look at the attributes, we've got a collider tab, right there. And we want our sweep to do the colliding, so we drag that down there. And then we've got solver type and this is really important to set before we move forward. Just shrink the spec a little bit. And I'm going to change that solver, let's look at the options. We've got "inside," "inside stretch," "outside," "outside volume," "intersect." So this is a collision that's going to occur outside. And the object that's sort of receiving the collision, the sphere, it's a closed object. So it's technically a volume. So we need to chose "outside volume." And now, let me just put this on. "Materials"-- I forgot I had these. Make things look a little nicer. We can go in and start increasing the radius of this sphere. Yeah, this is the "ah" moment, the "ooh." You get that. And, you know if you guys work in 3D, you know this is sort of a tough thing to pull off, modeling. It's time consuming. It's pretty amazing. This little "primitives" here, you know, we can go in now and adjust the segment number. Still, haven't made this out of the ball yet. One other thing to show you with the collision is under the advance tab, you've got some fun attributes to play with. If you want this collision to-- if you want basically the trough to be much narrower, or wider, you can adjust these parameters. So let's do that one at a time and see if we can get a different result. Pull this back. And we'll increase the size say to 10. And I'm going to stretch down. I think that's what we want to do. And increase the sphere radius again. We decrease the radius of that collision and kind of get a nice, tighter, little pucker around there. So, I'm always looking for ways to make things look a bit more tissue like or organic and collision is wonderful to experiment with. And I think one of the great things about it is it's very real time. See, we don't even have the play head running and we're getting a response and we're using "primitives."
Dynamic texture deformations with the Tension Tag
So I'm going to show you a lonely little tag right now, and we're going to use the collision to
Cells from a membrane with Source FalloffOkay. I'm going to show you another shot. We're going to do a little breakdown, a little breakdown. - [Narrator] Cellectis. Immuno oncology. Pioneering gene-editing. - All right, so there's a scene in this animation where the immune cell binds to a tumor, cancer cell and got a little immune response and the preferin is emitted out of the surface of the immune cell, right there. There's a longer version of it somewhere else. So I'm going to show you guys how to make those little pits that open up and you get that neat little particle effect coming out of there. It's.. I think it looks really good and it's very, very easy to set up. So I'm going to start with a plane. I will increase the scale of it a little bit. And we'll go ahead and put it in a subdivision surface. And then I'm going to go to "simulate, " "particles, " and grab an emitter. Rotate this. So we're emitting up. And I'm going to set it just behind the plane. Down here. And increase the size of it. Seeing how big is my plane, 700, so we'll do about 666. All right. Cool. And click "play, " let's just see how this looks here. We'll go up to 300 frames so there's time to watch. And then we'll decrease the number of particles by quite a bit. Try three. Okay, that should be good. Might need less. So, a couple of new things here. I need this playing. I'm going to grab a "displacer" which, if you guys have used Cinema, I'm sure you've used, it's a really popular deformer for getting, you know, an undulating cell or a cell surface, you know, nice organic forms. But it's got a really neat function in its fall off. I'm going to stick this under the plane. And we're going to go to "fall off" and look at the shape and we can go down here, there is an "option source." And the crazy thing about that is you can put your emitter in as the source link and now, if under the shading, it's not doing anything yet. We need to add something into the shading tab. I click "color." Now the...our little particles are actually going to affect the displacement. And we can tweak that a lot if we go to "fall off"...actually, let's make it bump up a bit more so we can see it. A little bit on here on there. Here we go. Let's emit to 300 frames. And increase the size of this a little bit more. So in the "fall off" tab, you were wondering, "Can we adjust the shape of these more?" There's the sample distance and as we increase that, it will increase, basically, the radius of these pits, or these bumps. We will see, they'll kind of flatten out at the top. That's because of our fall off, it's at 50%. If we set that to 100%, we should get some nice domes. It's pretty cool. And we just want to invert them, basically. So we're going to take the height and crank it down, and now we get these little pits that open up. So, I'm going to copy this emitter. And this is something I do a lot. Set something up and then I want something else to happen, basically, within those same parameters. So, I copy whatever at the generator is or the group of objects that have combined to make some sort of effect. So everything stays registered. You'll see what I mean when I do this next thing. I'm going to grab a sphere and...let's turn this displacement off. You put the sphere beneath the emitter which is the same...has the exact same parameters of this guy up here. So this one as "one," this one as "two." And we just, we need to click "show objects." And if I shrink this back, it's actually going to look pretty neat. You'll see how these guys kind of look like they're popping out now. All right, looks kind of cool. It's all right. I'm going to decrease...I think visually, it'll look better if these emitters are smaller. A little bit smaller. All right, so we're halfway there with this one. Instead of one big ball coming out, we want a little pocket of particles that sort of spread out. But I did think this looks cool, you know? If you need, kind of extreme close up of some sort of membrane reaction. Just remember, like 3D isn't always about recreating, it's almost never. Unless if you're doing like super, super hi-end simulation about recreating what's really happening. So it is smoke and mirrors and it's okay that this is how it looks on this side because no body but you knows about this side. All right. So actually this one took me a little while to figure out because I needed to set it up fast, it needed to work very well and be, you know, robust, simple, easy to change and update. And I thought, "There's got to be a way to do it with a cloner." But, I'm sure you guys have played with maybe putting a cloner inside a cloner and run into problems. So, what I did here, was decided I would use this sphere as kind of my reference for where these particles are going to exist. Let me turn this "emitter" off. We'll hide the plane for now. And I'm just going to make a simple cube. We'll give it its own material and shrink the size of this cube down. I'm going to hide this sphere. I don't need to see it, actually. And then I'm going to grab a cloner. Cloner, we're going to use in object mode and the sphere is the object of reference. Now, just kind of a, you know, learning from past mistakes, if you're ever cloning to an object and that object has tons of vertices, often a good idea to deactivate the cloner before you drag the object you're going to clone into it. And then you can go in and change your settings down here and then turn it back on. So I don't want the distribution to be a vertex. I want it to be a volume. And "count, " we'll put down to like 24, 20 and we'll "render instance." We're going to be able to get away with render instancing here. And turn the cloner on and there, we've got cloned little volume. Last thing we need to do is decrease the size of these guys. And now, what we can do is group all this stuff together. I need to put it all under the emitter and then group it all together which on a PC is control G. No? Alt G. Yes. And we'll turn that emitter on and we'll just see what happens. And that's cool, that's what we want. We're trying to keep everything simple. Everything easy to adjust and update as needed and turn this other layer on now, and we're off to kind of a good start up here. It's all right, this is all our clones inside this sphere. I can turn this back on so you can see them. Now, what we want is as they come out of these pits to start to spread out. And to do that, first we just need to make sure that we're not using the render instances in this emitter because each group of these needs to be treated as its own set of objects. So I'm going to select the "cloner" and grab our good friend, the "random effector." Yeah? Every time I get a random effector that happens. And I'm going to set the random effectors fall off to "linear" and we're going to position it... I always forget which way is which with this, so let's really crank these parameters. Right. And we're going to position it like so. Extend this a bit longer. Leave it up here. And we'll set the fall off to 100%. Cool. So now... Super simple setup. From here we can tweak this at, you know, like secondary motion, rotation, things like that. But, potentially a very complicated particle effect with a pretty easy solution. We don't even have any editable objects over here. We're still, you know, using primitive objects and very few of them. So, yeah. That's that one. Okay. Let's move on.
Creating a gimbalI'm going to show you a super quick one here.so this is the...like the little teaser thing I made for the AMI this year, you guys might have seen. ♪ [music] ♪ And, like the animation part of this, it took just a couple of minutes to set up. And I just want to show you one piece of it. Just one of those, kind of, "Aha," like, "Oh, I can just combine these three objects and get this kind of effect." I think it's good for us to think about both the mechanical and organic effects in 3D and this is just a simple mechanical thing. So the way I made that gimble which is the thing that the RBC is rotating in, it's just this series of tubes. So I make one tube and position it like that. And let's say this is the outer ring that's totally stationary, unless it's bobbing up and down by some other, some other motions, move force, some other mechanics. And then I want another ring inside of this that's going to rotate. So, I'll copy and make another tube a child. Make that guy a little thinner. And then what I'm going to do is add the great "vibrate" tag to this and turn on "enable rotation" and click "play." Crank up the amplitude of this angle here. Crank down the motion, you get that. We can have it rotating the other way if we wanted to. So, let's do that. I'm just going to go with "vibrate" tag to make sure things are zeroed out again, it likes to return things to different positions. So, let's zero this out. Click "play" and we'll crank this guy up over here. Right. And let's make one more of these cylinders. Again, zero this out. Copy. Make it a child. Scale it. Make it a little thinner. And, we're going to click "play" so you can see this. Crank up that original amplitude angle and you can get that. I like this because, for some reason, the sum is way, way greater than the parts. It has a really cool life-like feel to it. But it took almost nothing to get there. And then of course, you can go in and add the little connections and whatever ornate things you want to add. And this is all one, sort of, single unit. So it moves around, and it still continues to function like this. So, that's that guy. One that's sort of similar to the preferin particles coming out.
Cells from a membrane with MetaballsSo in the demo, there's this scene...right there. It's, you know, kind of the viruses budding. ♪ [music] ♪ nd so I thought I'd show you guys how I did that. The disclaimer, this is one of those...conceptualize the receptor should be sitting on the surface already as these bud off. But still looks cool. All right. So we're going to use some meta balls for this which are still great and come in handy. Just a few little things to think about when you're playing with meta balls. We're going to make this kind of plane meta ball. The reason I do this instead of a sphere is we don't have quite as much geometry as if I was using an entire sphere as sort of my area where these are going to bud from. So it's a bit more manageable. And then I'm going to create an emitter. "Simulate," "particles emitter." And actually, for a minute, we're going to turn off our meta ball while we set some stuff up. Position this emitter, kind of like we did in the other scene. Increase the size a bit. And I will say this about Cinema, I will always enjoy that everyone has a different style in the way they work and that it supports that. I'm more of the, kind of "get my hands dirty, play in the view port." I don't really care if, you know, I'm dealing with even numbers or if this emitter is like pointed at a certain specific way. I like everything to be slightly off. But if you're the kind of person who wants to basically do everything by punching numbers in, it functions that way, you know, just as well, you know? But I think both have their pros and cons but you'll see that I'm...I try not to over-think these things too much. All right, that should do. So, I'm going to make two spheres now. One and then we'll copy it. And these things, I just want to make sure they all stay in the center of my scene because we need things to stay registered here in a minute. Let's shrink these down and I'm going to go ahead and set up the receptors that are going to butt off with the sphere. So I'm going to hide everything but one sphere. And I'm going to make this an "icosa." And I'm going to bring these segments way down. Create a cloner. Create a cube. Scale the cube way, way down. And then we will do object mode. Use that sphere as our reference. And clone the cubes. "Render instance." And scale these down. And we're going to have these cloned from the "poly-center," like that. And we'll make them a little bit taller. All right, cool. That should work. So, what we want to do now is set up our blebbing-off of meta ball spheres. So I'll turn the meta ball and the plane back on. And I'm going to take this...oh, good. Emitter's where it needs to be. I'm going to take one of my spheres, the one I wasn't using and go ahead and put it inside this emitter. Input the emitter inside the...underneath the meta ball generator. And turn that sphere on, make sure under the emitter we've got show objects and click "play." All right. Let's for now increase the editor subdivisions. And hopefully the scale of my scene is going to be okay for this. Decrease these guys. I'm going to do quite a few less particles here too. We'll do three. And you'll emit 'til the end of this scene, 300 frames. Click "play." Okay. Let's see if we can crank this back up now. So you get kind of the nice typical, what we like about meta balls thing going here. So now what we can do is copy this emitter because it's exactly where we need it to be. We'll delete this sphere. Group all this stuff that we need to make the receptors, group all of that together. And put that inside the emitter. We can use "render instances" here because we're not deforming those or changing them in any way. And we're going to hide with the sphere that we're using as our clone object. Drop some materials on these guys. And we'll see what we get. What did I do? Took that emitter out from meta ball. So that's the basic idea. And just, again, sort of registering two effects so that they're occurring in the same place at the same time. I've got a little bit more time?
Subsurface ScatteringOkay. I'm going to try do something on the fly here and we'll see if it...how it goes. I think it'll go all right. I just wanted to show you guys the sub-surface scattering in Cinema. It's really easy to use. I think it's a very beautiful and maybe sometimes it's just not set up quite correctly. And let's also play around with the "deformer" a little bit to get a shape that we'll throw some lights on and some sub-surface on. Let's try doing this with a sphere "icosa." And we'll go ahead and throw this into subdivision surface. And increase the radius a bit here. Put a displacer on here. I'm going to add a noise so I get a nice little undulation on the surface. Crank up the height. Now, one of the cool things maybe you've accidentally done this is, you know, you can't get a concavity from a noise because there's no way for that dark going to light to somehow wrap around back to dark, you know, above that information. But if we just copy this displacer and paste it below here, we can start to get some nice weird shapes. We increase these segments there. Actually, I'm going to put these, grouped with the subdivision surface. It'll do a lot better that way. So when you back up here a little bit, we need to...we need plenty of vertices and originally I had it under the sphere so it was just kind of looking at that many vertices. But if I, kind of, use the subdivision surface as a...like a null object to group it together, it will look at the vertices being generated by the subdivision surface. So, let's make the scale of this a lot bigger. Decrease the height a little bit. And then we scale slightly better. And then copy and paste. And there you go. You can see you're starting to get ares that are getting pinched or really...I don't know the technical term, but it's a shape you can't get with just a single noise. And you can really kind of push this and get some fun stuff out of it. So to do that, we just need to animate the noise. So I can go back to my shading, to my noise. Have the play head going and just start increasing the animation speed. You get that. We can do that with both. You get, like, a couple octaves of motion here. Let's toss a material on this. And I'm just going to put one light behind it, like right about there, kind of off to the side behind. And let's look at the material here. So I'm actually going to turn off, and I think this is one of the things that you don't realize you can do is just get rid of the color channel all together. And, go to "luminance," go to "effects," "sub-surface scattering." And we won't do anything else. We'll just render that and see what we get. So we get something pretty cool. It's not there, but it gives you the idea or where this can go. And a nice preset, if you're just looking for a preset it's under "presets," start with "cream." And maybe if we play with these lights a bit more. I'm going to copy this and add another one on this side, back here. And we'll make both of these lights, "area" lights. Give them some area shadows. Sorry, I'm not making them area lights but giving them area shadows and we'll have this one be a bit warmer. The pixels on this computer are, like, orange. They're not true white, unless I'm seeing things. It's weird. And really crank the intensity up on this. Move it over a little closer here. Actually, let's just start with that and see how that looks. I'll turn this other light off now. All right. So I think it's a lot of times kind of like the gooey-ness we're going for, subtle. It feels like it has substance to it. We'll turn on that other light. And just give it more of a cool color and make it a bit weaker. And then would love to talk to you guys a bit more about the the reflectance channel but... It's awesome and it's just one of those things that feels awkward at first but once you use it for a month or a couple weeks and you maybe go back to an older version of Cinema, you're really going to miss it because it makes things look really good and it's very powerful and very easy to use. So I'm going to get rid of the default "specular" and just add one of the shinies like "Beckmann" or "GGX," they're both pretty cool. And we won't use any reflection right now. But we want to use the "specular," there's really nice specular but we're not going to start seeing it until we bump up the roughness. So I'm just going to bring that up a bit. And there's our "specular," pops in there. And we're going to change this to additive and that's going to kind of combine everything here. I'm going to show you what it looks like. Why don't we add a bump to this also. Just want to get a little bit more "specular" play on there. See what that looks like. Right. Going to move my light towards the front here. And you know what? Let me show you this. Actually, this is a better idea. So I want to keep these lights where they are because they're really doing the illumination of the sub-surface scattering. But I want to get some cool "specular" on this object as well. But I know it's going to mess up my sub-surface if I just throw a light out here. The amazing thing about the 3D world is, you know, the fact that you can assign a light to a certain object is a crazy, powerful concept. In the same way, we make this light just cast a "specular." So, I often mess this up, but I think we just turn off diffuse, leave "specular" on and I think we're good. Bump up the "specular" a bit more. Okay. So there's something you started tweaking you can see, you can start, you know, hitting those kind of "wet light" points that are hard to figure out. And actually if we add in a little reflection with it now it should look pretty cool. It's just reflecting off itself. Yeah. But it's nice because it give us a little bit of value variation in there. So can you see that? Does it look... - [Man] Looks kind of cool. - Okay. All right guys. I think that's good for me. Yeah. - Awesome. Thanks, Tom.