Transforming Robot Production Pipeline Volume 10: Compositing

In this lesson, we're going to import our final clean plate and learn how we can add movement to our trees whenever our truck passes. So here's where we left off at the 10_begin. Now we've got a lot of work done on our foreground, but we have almost nothing done on our background. Now sometimes we'll have the clean plate and we can't really do much to it, but in our earlier course, Volume 7, we went in and we cleaned up our plate, we added a sky, and did some changes. Now currently, I'm just importing the denoised version of the plate and not the final clean plate that we have. So inside of your nuke scripts, you'll find Matchmove_end, which is the new script we finished up with at the end of Volume 7. So let's select all of these nodes and copy them over. Now, you might be tempted to Control click on the bottom and select nodes that way, however, that is not going to select a few of our trackers, which are important for our rotoscoping. So I'm just going to select everything with a drag selection, and jump back to 10. And let's drop this in where our background is going to go. And let's actually give ourself a little space to work in. So now, let's connect this in to our last node, the roto node, and now you're going to see our sky come in really nicely. And now let's take a look at how we can come in and make our trees move whenever the truck comes close to them. Now, the current problem we're having is that there's not a lot of integration with the foreground elements and the background elements. So we need to look for various ways to combine the two or combine the physicality of the two so that we have a better integration. Now around Frame 42, Frame 44, the truck skids perilously close to this set of trees here, and so what we want to do is we want to move the treetops here as if the wind from our truck is moving them as it passes. Now, we are going to be adding in motion blur into our background, but adding in a little bit of movement will help sell our shot and help sell that the foreground actually was with the background, or was shot together. So let's now take a look at where we have our trees isolated on an alpha channel so that we're not editing the background clouds. So I'm just going to begin climbing up this node tree here, looking for where our two are separated. And if we go to the top scan line render node, which is our last 2D node, we have no separation. No problem. Let's just drop in another scan line render and separate our foreground and sky background. So I'm just going to Control click move those back, copy our scan line render, connect in the camera, connect in the background. And for our object, we want whatever the sky background object is. So that's going to be this sphere, here. So let's disconnect it from our current scene, move it over, and connect it to our second scan line render node. So now if we take a look at these, we have our foreground with the nice alpha channel ready to be warped, and we have our background sky ready to be composited behind our foreground. So to get this back to looking nice, let's select both of these scan line render nodes, hit the m key to drop in a merge, and we're essentially back where we started. Now, however, we do have a brighter sky here, and that's because we're using a non-black constant. So let's change our constant from this off-blue color to a value of 0. And that will give us the correct composite, just as if we had everything still connected into this one scan line render node. All right. So I'm going to move everything up again, so I'm just going to hold Control and Shift and give myself a little space between our scan line render and the merge. And now, let's drop in a spline warp node. So I'm going to drop in spline warp. And again, we're not really going go over this in too much detail. We have quite a few lessons about the spine warp node online both in the new features of Nuke 6.3 V1 as well as in our new Transform Reference Library. You'll find a lot of videos about this specific node. So the basics of this. Let's jump to one of our earlier frames, let's say Frame 45. And let's draw out a line. And we'll give our viewer a second to update. So let's draw a line along one of these branches here. And now we can move this and our branch will move. However, the rest of our scene is going to distort as well, and we want to isolate this only to our trees. We do not want to be shoving the ground underneath it around our object. Now, if you ever want to reset a point, we can always right-click, reset the destination or hit Shift e, and that will bring everything back to normal. Now, we want to isolate this only in this area. So let's grab an Ellipse tool and let's draw an ellipse around this area here. Now, we want to be careful and make sure that this is a boundary surface or a boundary curve. So on our Ellipse layer, let's set this as a hard boundary, meaning no pixels outside of this can change. And now we can move this around to better grab our ground area here. And now, if we make a change to this curve, it's only going to affect areas in the local or inside of our boundary curve. All right. So I'm just going to reset that again. So let's draw out a few more curves and we'll jump back to our Bezier, and, of course, you can use B-Spline if you prefer that type of curve. I'm just going to draw out a quick few shapes where our various trees are. Now, I'm not going to change this tree over here, I'm just going to let this go. So let's actually draw a shape here just to sort of hold the shape of the tree and keep it where it is. OK. So now we've run into a problem. Well, we haven't until we change times. Now, if we change times, you'll notice that, of course, our roto or our spline warp is not sticking with our background image. So we're going to drop in a tracker node to find out the transformation that's happening to our image. So let's hit Tab. Drop in a tracker. Connect it up to our scan line render. And for ease of use, let's just track these two poles here. It's relatively close to the tree-- and we could actually track the shadows here of the tree to get an accurate movement. And let's do that. So let's track this shadow. It's going to tell us No Frame Range, no problem. Let's hit Tab. Drop in a frame range node, and connect this up, just to tell the node's down pipe what the frame range is because the scan line render is not passing along that information. So once that's done, let's increase our scan area and track backwards. If you want to learn more about tracking, we have an Introduction to Tracking in Nuke course and it goes over the tracker node quite extensively. Now, we don't need the entire sequence, so if we get to the mid-20s, let's stop it, jump back to our first frame, and begin tracking forward. And again, after it gets to about 70, let's stop it and continue on. As always, there might be a few areas where the track jumps off and we need to, of course, manually fix that. OK. So now, if you've got one solid track, let's go in and do one more track. I'm going to do this at the base of these trees. We need two tracks so we can get the translate, rotation, and scaling information here. So I'm going to track backwards for a little while, and then, again, let this go to mid-20s, or until it leaves the frame, and track forward a little bit. So once you've got your two trackers set up, let's come in and turn on the Translate Rotate Scaling properties of both of these trackers. And now, in our Transform tab, we're going to have the translation, the rotation, the scaling, and the center point to stick in this area here. And since this is pretty close to our spline warp, we shouldn't have to modify it too much. So let's go back our spline warp. And the first thing we need to do to connect these two is figure out which frame we drew these lines on-- in this case, Frame 45. And I like having just one frame that everything is drawn on. It makes things a little simpler. So let's grab our Root folder here, our Root layer. Go to the Transform tab and open up our tracker. And now, let's Control drag all of our tracker information down into our Transform tab. Now, initially, this is going to look very broken, and we're actually going to come in and fix this by clicking Set-- whoops, excuse me. I accidentally connected our center to the skew. That's definitely not what I wanted. So let's click Set to This Frame, which is going to offset all of these values to the current frame. And now, if we run through our time, we should have a pretty accurate track. Now, it's not going to be pixel perfect. You'll notice that some of these trackers or some of our splines are starting to drift off. But really, we're only going to be spline warping this over, I'd say, 20 frames, and in those 20 frames, we can see that it is sticking rather well. OK. So we've got our track set up. We've got our points set up. And I'm actually going to stop the lesson here and jump into the next lesson, where we're going to do some animation on these splines and use animation principles such as Follow Through and Overlapping Motion to create the illusion that these are actually moving as a natural object would. So, in this lesson, we brought in our background nodes from our, again, Volume 7 Match Moving Course so that we have our final sky as well as our final camera movement, both are very important to finishing this off. And we came in and we've begun working on our spline warp node and our tracker to be able to move these trees or have these trees react to our truck driving past them.