Join Paul F. Aubin for an in-depth discussion in this video Building the leaf structure, part of HBIM: Historic Building Re-creation.
In this movie we're going to begin creating the Leaves that wrap around the bottom of the Corinthian Capital. Now there's two rows of Leaves. We have a short set of Leaves and then a tall set of Leaves that wrap all the way around the lower portion of the Capital and then there's some more free-form Leaves that occur elsewhere. We're going to follow the same basic process for all of the Leaves that we create. In this video, I want to look at a slight variation on the process that we used in some of the previous videos in the earlier chapters. We're still going to need a Path. We're still going to have a Spline Path that we're going to create our 3D form from.
And we're still going to have a series of Profiles. But, instead of doing a Nested Profile Family for this Leaf, I thought I would show you an alternative where we can actually draw the Profiles directly on those Work Planes of the Points. Here you can see an illustration of what we're going to create. And it is a little dense, I grant you that. There's a lot going on here. But we're going to create a series of Profiles, like you see here, with reference lines and we're going to be driving all of them with these parameters. And this just offers you an alternative way to approach the creation of these Lofted Forms.
So, let's jump over to Revit. I'm in a starting file, here, where I already have some of those Ribs in place, but, what we're going to do is zoom in towards the bottom and look through the entire process of how to create each of those Ribs and then learn how to copy them and then, ultimately, create the Leaf from that. I'm going to zoom in down the bottom. We want to ultimately build this rig. This rig contains two arcs that are kind of meeting at the end points, but have a little bit of gap in the middle that will provide the thickness of the Leaf.
And those are carried by a series of four Reference Points. We've got one here, one over here at the end, and then these two here, in the middle. And all of that is hosted back to and driven by this one Reference Point here. And notice that that Reference Point is hosted to the curve. As I move it along the curve, it will move everything and create the relationship that we're looking for. Let me undo that and let's build that from scratch. I'm just going to kind of zoom in here and start the whole process over again.
I'm going to click a point and the only thing you want to make sure you do here is make sure the Draw and Face is selected. It should do that by default, but just make sure that that's chosen. and then click anywhere on the Spline Curve. Now, again, sometimes it doesn't show up right away, if you just pan just a little bit, it'll refresh the screen and get that to show up. Let me click my Modify tool and Cancel. This point, if you select it, it will show that one plane and it is now moving along this curve.
So, that's the first step. We've got a hosted point associated with this curve. Now I'm going to select that point and down here, on the Properties Palette, there's a Show Reference Planes feature and I want to change that to Always. And so, now, even if you deselect it, it will continue to show the work plane that's associated with that point. This point you can see displays a little differently. So, in addition to Always, I also want you to do is where it says Show Normal Reference Plane Only I want you to un-check that.
And then that will show all three Reference Planes. So now we have a work plane for the X-direction, a work plane for the Y-direction, a work plane for the Z-direction. And what's nice about that is we can host Geometry on any one of those three planes. So that's how this point is ultimately carrying all of this Geometry. The first thing that I want to do is I want to create these two points that are here. Now those two points actually run, if we look back at the left view, you can see that they run perpendicular to the curve.
They kind of go out this way in the case of this point. So back here, in the 3D view, I want to host them on -- if I press Tab here -- I want to host them on that plane right there. So that's the important thing, is you have to know which plane you want to host these points on. So let's go to Point and then, before you place it, click the Set Work Plane button. So now you can go in and either select this plane or this plan or this plane. So move your mouse around to get the right one.
Use your Tab key, but make sure that you're picking the one that runs to give you that perpendicular relationship to the curve and then place your point in exactly the same spot and Revit will complain about that and tell you you have two points in the same spot and you're just going to want to click OK and say, "That's all right, Revit. I've got this covered." Okay? And then do it again. Looks like I missed that time, I should have gotten the error message. You want to make sure it's right in the same spot and then you get that error and click OK. All right? So now I have two points that are exactly in the same spot.
Let's cancel the command and go in there and select one of those points. Now, I don't know which one that is, it's probably the second one I created. It doesn't matter. You see these orange arrows? Those orange arrows let you drag the point and the point that I'm interested in dragging is the direction that's perpendicular to the work plane. Now, if I do it again and click the other point, drag it out, that's kind of what I'm looking for. I want those two points to be set away from the work plane by some distance.
Now, if you come back to the original point, and just drag it a little bit, notice that it's taking those two points with it. And that's the whole key to this technique. By hosting the points on the work planes of the main point, you build this series of relationships that we're after. So let's repeat that in the other direction. I'm going to go back to the Point Element and click the Set Work Plane again. But this time, I want to use this Work Plane, the one that's parallel to the Spline rather than the one that's perpendicular to it. Use your tab key if you have to.
Click the point right in the same spot, click OK, then do it a second time and click OK. Now, I'll cancel the command, I'll select one of the points, and as before, you can use the control handles on screen to move this if you want to and in this case it would be the little red one, but what I'm gong to do instead is if you scroll down, what that actually is doing is changing the Offset Parameter. So this time I'm just going to put that in numerically and I'm just going to use a random number here for now. I'll use 3 and then I'll select this one and I'm going to do -3 so that it offsets the same amount.
And that gives me the four points that, if I zoom out here, we were using to create these curves. Well, I need several more of these. If I zoom out here, you can see that there's already a few in the file, but there's like nine total that are required to create this leaf. It turns out through some trial and error I've found that you can copy this whole rig of points, but you need to do it before you create the reference lines. So, what I'm going to is select just the five points.
I want the hosted point and the four ones that I just created. Over here, it should say Reference Points (5). Highlight the main host point with your mouse, but don't click, because if you click, it will deselect everything. Hold down the Control key and then click and drag the point. And when you let go, it will create a copy. Now, if you deselect everything, and you move that copied Host Point, notice that the new points are copied to it.
That's the trick to saving yourself a ton of work here. So, again, I want to select just these five points, not this one. So hold the Shift key down and remove that one. It should say Points (5) and then Control drag as many times as I need this. So, for now, I'll just do a couple copies. And that's ultimately how all of these came over there. The one thing you will notice, though, is this one is pointing this way and this one is pointing this way. So the reason I left a few of these in here is just to kind of illustrate that.
So, I'm going to take this one, at the top, and I'm going to pull it over the top and you see how when you go over the top, it tries to snap to the endpoint? So, instead of doing that, I'm going to click this one and that's at 0.65 So I'm going to take this one and I'm just going to set it numerically to get it to where I want it to go instead of trying to drag it there. So let's try about 0.8 for that. Okay. So that puts it over here, where it needs to go, but you can see that it's pointing the wrong way.
All I need to do is take that point and if you look here on the Properties, there is a Rotation Angle. It's currently 0. I'll change that to 180 and that will just flip the point around and you see how it took the hosted points with it. So that's really the easiest way to kind of take this hosted point and make sure that it's oriented in the correct location. Now, I'm just going to do one more thing here. I'm going to show you how to actually build the arcs here and that's going to be to select three of the hosted points.
So I'm back down to the original one, at the bottom now and I've selected three of the hosted points. You don't include the main one. That one never gets included. It's just the three that are hosted. So one that's offset vertically and two that are offset horizontally and then you use this button here, on the Ribbon, to create a Spline Through Points and Revit will pass a Spline Curve through those three selected points. I'm going to select this point and then the two ends again. The two ends are shared by both Splines and do it a second time.
Now that does create model lines. So all you have to do is select those two model lines, come down here and check Is Reference Line and now you've got reference lines. And you really do want them to be reference lines because they are more flexible that way. Once again, they won't get absorbed into the 3D form when you create form. They will remain outside of the form and you will be able to manipulate them. So one more time, you select the three points and, unfortunately, there's no way to copy this. You just have to sort of do it each time.
So it does get a little bit tedious. And then Spline through points. Then you select both of them and turn them into Reference Lines. Okay? So that's how all these ribs get created. Now, in order to control them more precisely, we're going to actually take all those offset parameters that are driving these points and, instead of typing in the numbers manually, it will be a little bit more efficient to do that with parameters. So if we put the parameters in, we'll be able to kind of fine-tune it and as we change the design and kind of fiddle with it, we can just adjust the parameters and see it adjust in real time.
But that will be the subject of the next movie.
- Researching source materials and source drawings
- Sketching and modeling architecture
- Setting up the project in Revit
- Modeling overall forms
- Using system families
- Adding details such as columns and moldings
- Creating an interior model
- Rendering the project