Join Scott Onstott for an in-depth discussion in this video Loft a handle with Curviloft, part of SketchUp Tips.
- [Instructor] Last week I made this vase, using the bezier spline tools that you see here. And this week, I'd like to model handles, which are present in the image, which was the basis of this model. The image is part of this file, so we can go to Edit, Unhide All, and you can see the image there, with the handles. So I'm going to select the vase, and hide that temporarily, so I can just focus in on this image. Also, let's view that from the front, and change the mode to Parallel Projection, and then zoom in here, let's model just the left handle.
So I'm going to zoom in there. Now this type of form is ideally suited to a loft, and the term loft is used in many other 3D applications for this type of geometry that has a number of cross-sections along a path. SketchUp doesn't have a tool like that, though, so we need to resort to accessing this functionality through an extension. Let's open up the SketchUcation ExtensionStore, and then search for loft, and you'll see that Fredo6 also has another tool here, called Curviloft.
I'm going to install that, and say Yes, and OK. Fredo6's plugins also require that you install his library of code, which I've already done, and you can see that right here in the Extension Manager. So if you don't have this, you'll need to install it also. Once you've installed that, you can go up to the View menu, and open up the Curviloft Tool Palette, and here it is.
So these three icons represent the three different ways you can make lofts. The first one here is, you can make a surface from a number of cross-sections. So we have a face that's generated by drawing a lot of different splines, and then lofting them together. In this middle example, you can make a loft by having different cross-sections along a path, and that's what we need here. And you can also make a loft from a network of curves. So we're going to be using this middle tool. Incidentally, you can also access that from the Tools menu, down here, using this option.
Okay, now what we need to do to generate this is to draw in the path first, and then a number of cross-sectional profiles. So this path, I'm going to draw down the center of the handle, and I'm going to use the Bezier Spline tool up here for that purpose. I'm going to start that down here in the body of the vase somewhere, and then I'm just going to click points, kind of eyeballing the center of that handle, more or less.
And over here, I'm going to decide just to follow this kind of crease down the side here where the handle meets the vase, and I'll just have that go down to about this location where it meets this kind of ridge. Then I'll right-click and choose Done, and switch to Addition, which is the editing mode for this tool. And then I can come up here and adjust the positions of these points if need be.
I'll just make some subtle changes like that, and then I'll click off to the side to finish that. Then when I orbit, you can see that that is on the sketch, or the image, rather. The next thing I need to do is draw in cross-sectional profiles. So in this case, these are round, so I'll use a circle. And the circle that I'm going to place down here, I'm going to, before I click, I'm going to press the Up Arrow on the keyboard, to indicate that I want to draw that in the blue direction, and then I can click to specify the center point, and then click a second point out here somewhere to specify the radius.
This is casting a shadow, so I'll just turn off shadows for now. The next thing I should do is reorient that, so I'm going to go to the Select tool, double-click on that, go to the Rotate tool, and I want to rotate that around the green direction, so with a green protractor shown, I'm going to hold down the Shift key, and that will lock that direction and turn that purple.
And then I can click on the center point there, then I can let go of the Shift key. And then click a point over here to start rotating it, and then place it down when it's more or less perpendicular to the path like that. So there's my first cross-section. Also, you should take a look at the number of segments in your circle, so I'm going to select just the circle. You can see up here on Entity Info that it has 24 segments, which seems like about the right number in this case.
We don't want to have too many, because then the handle will be overly-complicated, and we don't want to have so few that it looks really blocky, and this is sort of a nice compromise. Okay, so now I'm going to draw in another circle up here somewhere on the path. Again, press the Up Arrow, click the center point, and then click a point out here. Now if we're going to err, we're going to err on the side of making this a little too small, because if it's too big, it's going to pick up that white color when we assign the material to it later.
So I'm going to make it just a little bit smaller than that image. Rotate this like we did before. About like that. And then, again, up here somewhere, I'll draw in another cross-section, and it's about like that. And then rotate it again.
Now this one is a little off, I have to say, so what I'm going to do is move this down a little bit, and then I'll go and select this, and right click, and then edit that, and just bring this down a little bit. Okay. Now I'll draw in another cross-section over here, and then rotate that again.
And we should rotate it in the same direction because the idea is here that, the loft is going to start at the bottom and it's going to kind of flip its way over, so we need to rotate it so that that makes sense. So the white color is visible from this side. Okay, now, I think this is just a little high, going to move it down a little, and then maybe adjust this one more time, so the path kind of lines up more or less with the center of the circle.
And then I think we could do just one more cross-section at the bottom of the path here. However, it's necessary to rotate that around 180 degrees. Otherwise, the loft would bend back against itself in the end. Okay, so we have the different pieces that are needed for that loft. I'm going to hide the image, revealing what we have drawn.
I'm also going to save this as, GreekVase2, in case SketchUp should crash. So now I'll click on this tool, and that opens up a special interface that we see up here. And the way that this works is you first have to select the path, by clicking on it, and then you need to select that with the blue icon here, and it's red now, and it has number one on it.
Then we need to select the cross-sections in order, so click on this one, and then click the blue arrow, and that has number two there, and then just keep doing that for each one of the cross-sections. And they've all been selected, so now I'm going to click on this green checkbox to validate the contours and go to Preview Mode, and now we can see a preview of the loft that will be generated.
You can orbit around and take a look at that. I think it looks pretty good overall. You can also tweak the parameters up here if you want, to experiment with the different methods that are used to generate this. We want this last method. And you can also tweak the parameters here however you like. I'm satisfied with the shape, so I'm going to click the green arrow at the end, which is Finish and Generate Geometry. And finally, you have to click this icon of the door that's closing to exit the tool.
So it outputted this new surface. And that's separate from the contour lines that we have there as well. So I'm going to Unhide All, and I'd like to assign a material to this handle using the image. So to do that, I need to double-click on the image to open the group, and then select the face, you can see that up here at Entity Info, and then use the Paint Bucket tool.
And on the Mac, you hold down the Command key. In Windows, you hold down the Alt key, to get the Eyedropper tool, and then click on the image to sample that material. You can then click outside the group to close it. Double-click on this new handle group to open it, select on this object so that you have the surface selected, and then use the Paint Bucket tool and click on that surface to assign the material.
Click outside that group to close it. And now what I'd like to do is make a window selection around all those circles and path, and then I'm going to hold down the Shift key and click on that to deselect the loft. I'm also going to hold down the Shift key and click on the image, then I'm going to hide all that stuff. And then, it looks like, this isn't quite long enough, so what I'll do is just move that down a little bit to hide that fact.
Now, I'd like to have a handle on the other side, so I can use the Rotate tool, click the line here, which is coming out of the center line of the vase, and then start rotating it. Press the Option key on the Mac, or the Control key in Windows, to enter Copy Mode, and copy it around 180 degrees, like that. And then, let's just have a better look at it. I'm going to go into Perspective Mode, and just have a look at that.
Also, I can turn shadows back on, and we can now see the shadow includes the handles, because these are three-dimensional objects. And there you have it, the vase is complete.