- In this Cineversity Quick Tip, we're going to look at how to use the Tracer Object to trace the paths of clones. Specifically, we're going to trace the clones here that are outlining this text. We covered this a few weeks ago. We showed how to animate these clones along this line using the Rate option. Now, what we want to do is simply create a spline based on the movement of those clones. This is actually super-easy in Cinema 4D. Just make sure your Cloner is selected, and go to MoGraph and choose the Tracer Object. You'll see here that in the trace link the Cloner is already chosen. If for some reason you didn't have the Cloner selected when you created the Tracer, you'll just want to delete whatever link is there. Hit the Pick icon and pick the correct object that you want to trace. You can see that by default the tracing mode is set to Trace Paths. So it will trace exactly the path that that clone takes. You can also see that for cloners, we're cloning the matrix. We're not tracing the actual clones themselves, but just the matrix of the clone. Now, when we play back the animation you can see that the Tracer is generating a spline that follows the path of each one of those clones. We have options here for the Sample Step, for instance. So we can choose to sample this spline less frequently, let's say every five frames, and we're going to get something that doesn't as much match the path of the clone. It's actually a little bit more jagged, and you can go in and adjust the spline interpolation as well. We could go with something like V Spline and you'll get that to smooth out a bit, especially if we increase the intermediate points. But that's not matching the shape anymore. So in a lot of cases, really most cases, you're going to want to leave the Sample Step at one. You might have various reasons that you'll need to adjust the spline interpolation. But in a lot of cases, Linear with no interpolation will work just fine, because it's sampling every single frame. One area where the Tracer Object gets really cool is when you enable this Limit option. Really, From Start is not super-useful, but From End is extremely valuable. Because here, we can actually adjust how long the trace occurs for, or how long the trailing line will be. So right now, with it set at one, we're only going to get a tiny line following one frame behind each of the clones. If we set this up to something like 10, we're going to get 10 frames of the line always existing behind the clone. That's still a little bit short. So we can go ahead and increase this to something like 20, and now you can see that we've got a nice trailing line behind each clone. Now, you can treat the Tracer output basically just like any other spline in Cinema 4D. You can render it using a Sweep NURBS Object, using the Hair material, or a Sketch Object. Let's just go ahead and add a Sweep NURBS for the simplistic sample. We'll go ahead and add an n-Side. I like to use those for my pipes, because it's real easy to control your segments. We'll drop the radius here down to three, and create a Sweep NURBS to drop both the profile and the Tracer path into. Now, you can see that we get a nice outline. We'll go ahead and add some color on that, and we can also go into the Sweep and adjust the scale, for instance, so that we can give it just a little bit of a taper at the end of those tails. Now, one last thing that I want to point out with the Tracer Object is that if we render right now, I'm just going to render a small, little region, you'll see that the trace line doesn't quite meet up with the light that's being cloned. This is actually a little bit of a priority issue, because Cinema 4D is evaluating the Tracer before it evaluates the Cloner. So in general, you always want to make sure that your Tracer Object exists lower in the Cinema 4D hierarchy than the object that you're tracing. So I'm tracing the Cloner, I want to make sure that happens earlier. In fact, because we're cloning on a spline, just for execution order it's a good idea to go ahead and put the spline above the Cloner. So now the spline is being generated, then the Cloner, and then the Tracer. Now, if we rewind and play again, you'll see that that light is actually butted right up against the front of the Tracer. Of course, this whole setup is completely parametric, so you can continue to adjust and tweak however you'd like. So that's a quick overview of the Tracer Object and how you can use it to quickly create outlines on your 3D text. I hope you enjoyed this tutorial, and if you did please like, share, and visit cineversity.com for more great tutorials and resources.