Join Paul F. Aubin for an in-depth discussion in this video Using a massing rig to build the abacus, part of HBIM: Historic Building Recreation.
- In this movie I want to explore how the medium detail version of the capital is structured. This family is actually made up of several additional nested families, so it's certainly more complex than the base family was. If you highlight any of the elements in here you'll see that each one of them is a nested generic model. So, what I've tried to do is break up the family into its constituent parts, and I have a diagram for that right here. So, we've looked at this diagram before, but this kind of shows us how the capital is structured in all of the little nested parts and pieces that are required.
Now, theoretically it would be possible to build this entire form in a single family, but it would be so difficult to get all the rotations and the orientations correct, and then when we consider the fact that we've got eight of each leaf, and four of each volute, and four of each flower, if we needed to change any one of those we'd have to erase the other three and recreate the three new ones, so, it's much easier instead to actually do these as nested families for two reasons: because you can open that family and you're working in a simpler environment now, because you only have to focus on the one item, and then, when you reload it, it reloads all of the instances, and they all update, so, it's definitely a more powerful way to work.
Now, it can make the file a little bit heavier, so there's definitely a trade off, but, I think it's definitely worth it. So, we've got each of these families here, and what I'll do is I'll just sort of go down here on the families branch of the project browser, and you can see each one of them listed, and I'm just going to open up several of these and just kind of show you how they're put together. Now, for the most part, most of these are kept fairly simple in the medium detail version, we're not using much more than extrusions here, and, again, I'm doing that on purpose because the medium detail version, I don't want it to get too detailed.
We're going to use this at medium level scales, you might use this at, you know, 1 to 100, or 1 to 50, or 1 to 25, or, the equivalent scales would be eighth inch, quarter inch, or half inch scales in Imperial files, so, you know, with those scales, you want to see a decent amount of detail, but you don't want to see too much detail were it becomes overwhelming. So the medium detail is really good for that. Alright, so, let's just start here at the top, the abacus and the bell, and I'm going to right-click that and choose Edit, and that's going to open up that family. Now, you'll notice that all of these are massing families, so, they've all been created in the massing environment, and again, the easiest way to tell that is we've got the gradient background, and we can see the datum elements on screen directly.
Also, we can look at the ribbon, and see that we're getting the massing environment tools. Now, in most cases, the reason I've done that is because we're going to be saving these as, and turning them into the fine detail versions, and most of the fine detail versions are really going to require the toolset that's available in the massing environment. Technically, this family right here, did not need to be a massing family. We could easily make this extrusion in the traditional environment, and we could easily make this extrusion in the traditional environment.
But, what I want to show you here is how this one is actually put together. There's not really much to show you with this cylinder, you just draw a circle and extrude it. So, quite literally, the basic process in the massing environment is you click first on a Work Plane that you want to use as your drawing plane, so, the level is actually at the top here, and I'm going to click on it to make it the Work Plane, then I'll deselect it and draw a circle off to the side here somewhere, deselect that, and when you select the circle you can click the Create Form button, and Revit will suggest a couple possible forms, you choose the one you want, and you've got a 3D form.
So, that's all that was required to create the drum portion. So, I'm going to delete that. But to create the abacus portion here, what I've actually done is taken advantage of what we like to call a rig. When I hover over these green lines here, these are actually reference lines, and you can tell they're reference lines because they have all that dashed stuff going on around them, and it's probably easier to understand that if I just draw a single reference line off to the side. So, it looks like a single line, but when you highlight it, what you actually see is that it's got a series of four Work Planes that go through that line.
We have one that runs horizontally through the line, one that runs vertically, and they both go along the length. If I go to the Set Work Plane, that's actually this one, and if I press Tab, this one. But then there was also one at the end, and one at the other end, so when I cancel out of there and I highlight it, that's what you're seeing dashed in is the possibility that there's these different Work Planes on there. Now, the way that reference lines work is you can use them to build rigs of geometry. So, at it's simplest form, this line right here can become the host for points or for other lines.
So, if I were to use the Set Work Plane option and pick a Work Plane here, and then draw a circle, notice that that circle is drawn on this line, and if I move that line, it takes the circle with it. If I restretch that line, it takes the circle with it. So, that's a really simple example. But what we're doing here is we're using something called reference points. When I select a reference point, and I click anywhere on that line and press Esc, that point is now associated along this line, and what's really powerful is if you scroll down in Properties, there is a parameter right here that you can put in a number from 0 to 1.
If I put in 0, it goes to one end of the line. If I put in 1, it goes to the other end of the line, but if I put in .25, it'll go 25 percent of the way along the line, and if the line were to reshape, notice that this point remains at the 25 percent point along that line. So, that's a hugely powerful way to start building these sort of complex rigs. So, if I cancel that, and delete all of that, that is exactly how this went together.
So, what I'm going to do is just off to the side over here, I'm going to go to Reference, click a rectangle, and I'm going to draw out a rectangular form. Now, you can put dimensions on this rectangle, and you can assign those dimensions to parameters, and I'll take both of those with the CTRL key, and set those to the base diameter, which makes that 60 units, and now that's a square.
Then, I can take points, and start placing them on the locations on that line. And those points are what I'm using right here to generate the chamfers, and to generate where these midpoints lie. So, to do the chamfers, what I did was, when you select one of the points, and notice that down here there's a property that says Measure From and it defaults to Beginning. But, you can actually change that to End. Now, the reason you might want to do that is because in addition, this Normalized Curve Parameter, which is that numerical value here, you can change that number to anything you want, as we've already seen, so like, maybe .1, that one's measured from the end, but then here's .1 measured from the beginning.
So, what that does is this space here on the left is now equal to that space on the right. But more importantly, I could select both of these points, and scroll down, and right next to the Normalized Curve Parameter is the Associate Family Parameter button, and this will allow me to choose one of the parameters in my file, and so, at the moment, the choices I have are my module and my part. So, I could select one of those, now, the reason that those are my choices is because Normalized Curve Parameter is actually numerical.
It's not a length. So, we could choose one of these, or we could click Add Parameter, I'm going to add paramter and just call this 'Offset', and click OK. So, now I've got a new parameter called Offset, it will inherit this .1 value, and it will now always be a tenth of a measurement from the end, so one tenth off the end. So, using one parameter, we could set all of those points all the way around. Now, let's compare that to what I actually did over here. If I select one of these points, this particular one is at the beginning, and this corresponding one on the opposite side is set to the end, and they both say four.
Well, when I click the equal sign there, what you'll see is that it's a whole different list of parameters that are actually showing there, and that says abacus corner, and in fact all of these, this one, this one, and the same two all the way around, so there's eight total, are all set to the abacus corner. Four of them are set to Beginning, four of them are set to End, and then they're all that four units. But the reason that it's using length measurement instead of number measurement is because in addition to being able to change whether it's beginning or end, you can also change the measurement type.
So, what I did is actually change the measurement type from the Normalized Curve Parameter, which is that 0 through 1 value, and I instead changed it to Segment Length. When you do Segment Length, now it's using a linear value, and then when we look in Family Types, I'm setting the abacus corner to part length times four. So, it's just another way of approaching it, but now whenever we flex this, this will always adjust this value to the part length times four, and it will always put that corner in the correct location.
So, those two points are controlling the chamfer here. Now, the same thing is occurring with this line. This line is actually hosted by this point, and this point, so the other piece of this that you want to see is, if you go to Reference Line, turn on 3D snapping, and click two points on existing lines, this line is now hosted by these points, and if I move this point, do you see how it actually adjusts that line? Now, right now I'm moving it totally randomly, but what if I took both of these points and came down here and set the Normalized Curve Parameter to some parameter? Well, that's exactly what I did here, and I didn't care so much about these points, I cared more about the location of this line, because ultimately it's this point that I was concerned with, and I just set that one at .5, meaning it's always going to be at the midpoint.
So, what does that give me? That means that I can now take this form, and if I delete it, what you can see is that I've got a new form in here that is going through all of those key points, and when I select that form and choose Create Form, it creates that extruded shape. Now, this one's extruding up, I actually extruded it down, and that gave me the form that I was looking for. So, that's using a rig, and it's a different way of using parametric relationships, it's definitely a different way of thinking than the traditional Family Editor, where you have lots of reference planes, and then you have to align and lock the corners of the angled lines, here you're passing the lines through those points, using that 3D snapping feature, but when you do that, it picks up all of those points, and creates that rig, and then then that rig can be turned into a 3D form.
NOTE: Registration for the rendering phase of Project Soane opens in January 2016. Render the Revit or RBX models in your favorite Autodesk software for the chance to win great prizes from HP and NVIDIA.
- 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