Join Paul F. Aubin for an in-depth discussion in this video Proportional scaling workaround, part of Project Soane: Recover a Lost Monument with BIM.
- In this movie we're going to look at an alternative technique to do scaling in your Revit families. And it's taking advantage of a rather odd little workaround. So, it turns out that if you use the planting category, there is a feature that allows families to be scalable based on a single parameter, so they will scale proportionally. Now, this is exactly what we need in classical families, is we want to flex one parameter and we want everything to scale proportionally. Now, up until now, we've been doing this with a series of parameters linked together with formulas.
And you may have noticed in the previous movie that we didn't do any of that. And if you were building the fluted shaft, you may have been wondering how it would flex. And the answer is, if you tried to flex it, it probably failed miserably. So what I chose to do there was to not really flex that family and not really do that. And instead, I'm going to use this technique. Now, this technique is a little bit of a workaround and it's a little bit odd but I think the tradeoff is worth it. So, the basic concept is quite simple. You create a new family based on the planting category.
But then you have to do this odd little thing where you have to double-nest it. And then once you do, you'll be able to flex the height parameter and it will flex the entire family. So let's go ahead and walk through the process. And we're going to build it completely from scratch so you can see just how easy this is to do. So I've got nothing open, as you can see. And I'm going to click the New link right here. And that takes me to the Select Template and I'll scroll down. And the first step is that you have to load the Planting family template. So I'm going to open that up.
And there's nothing to this. It's just an insertion point here in the center. It did open up several windows, so I'll just do Close Hidden Windows to dismiss those other windows. Now, let's take a look at family types. There's only one parameter in here, the height parameter. Now it's currently at 19 feet so one thing that I do want to do, it's not required but I think it will be a little bit nicer, is I'm going to go to Manage, Project Units, and I'm going to change the format of the units to the same format that we're using in the other files, decimal inches.
And if we go back to family types, now that's 228 inches. Well, the height of our shaft, by default, is 491 parts. Now we're thinking of inches as parts again. So I'm going to put in the 491. I'm not going to worry about scale yet. Okay, I just want to put in that correct proportion there. So that actually turns out to be kind of an important step, is you want to set that base height to your sort of starting height or your one value, if you want to think of it that, your unit value. So 491 will do the trick there. Now, I also want to add a material parameter.
So I'll call this Shaft Material. I'll make it a material parameter. Click OK, and click OK again. So that's all I need to do in this file to get it set up. The next step is to save it and give it a name. So I'll go to my Application menu and Save. And I'll just put it right here with my other shaft files. And I'm going to call it PLT_Shaft Fluted. PLT is my abbreviation for planting, and that just reminds me that this is a planting family.
And I'll save that. Then I'm going to immediately save it as and add the word Nested to the name. And that's because I actually need two, if you recall. So the trick is, I create a planting family, and then I create a second planting family and I nest one in the other. So the one that I've called Nested I'm going to bring in our fluted column. So if I go to my Application menu, I have it right here, Fine Shaft Fluted. This is the completed version of the file we worked on in the previous chapter.
And I'm going to come over here and choose Load into Project and Close. And I'll place it anywhere on screen. Now, I want it to link up to the material that we assigned, the material parameter that we created. So I'll select it. Go over here to the Properties palette, scroll down. There's my shaft material. I'll click the Associate Family Parameter, and choose my shaft material. Okay, so now, that's the first piece. I'll go ahead and save this.
Now this is the one I've called Nested. This is the one I want to bury inside of the second one. So I'm going to go back to my Application menu here and reopen my PLT_Shaft Fluted. This was the first copy before I did Save As. I'll switch back over to the Nested one, load it into project and close. Place it right there at the center. Cancel. Select it. Now this time, the material parameter is actually a type parameter now.
So I'll click over here and link up the parameter. And again, that's all I need to do. Now all we've really done is nest in our fluted shaft twice into two nested families. So let me save that. And the final step to show you how this behaves is to go to the Application menu. Do a New Project. I'll just use my Architectural Template. I'll switch back over. And I'll Load into Project and Close again and place it somewhere on screen.
Let's go to 3-D. I'm going to change the scale just so it looks a little bit better. And now, I'm going to select it and do Edit Type. So here's where we can put it to the test. So that 491 parts defaults to 40 and 11 inches. Let's try 30 feet. Click Apply and you see how the entire thing scales. Let's try 50 feet. Click Apply. So now, instead of having to do this large collection of individual parameters that are all linked together with these complex formulas and there's a lot of locking and aligning, and a lot of possibilities to forget one or have errors.
Now you can just take the entire family and say, "I want the whole thing to scale "based on the height." So the trick is, you've got to set your start height to the correct proportion and then you've got to do that double nesting. Now, this was first discovered, I believe, by a colleague of mine. His name is Kelvin Tam and he has a blog. And I've pulled it up here and just searched his blog for planting and showed you some of the posts that he's done on this in the past. So if you want to read more about this double nesting planting workaround, feel free to check out Kelvin's blog here.
But this technique is what we're going to be using for the capital as well because with all those detailed organic forms, it will free us up from having to worry about scaling all of that stuff. Now, I will say that in Renaissance Revit I did a little bit of both. So some of the volutes and some of the leaves and other components I'm scaling with the more traditional and linking up the parameters in the formulas and then some of them I'm using the nested family trick. Here with the Soane capital we're going to rely on the nested family trick a lot more heavily.
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