A Tale of Two Normals

As anyone who has used Revit to model geometry knows it does not really seem to care about "normals", which if you're familiar with most other 3D modeling software you know exactly what Normals are, even in Sketch-Up! But lets be realistic here, any 3D modeling software has to have surface normals, and occasionally even Revit can be bent to your will....

So, here's the scenario, lets say you have a solid box. If you create a spherical void that cuts the solid, you would expect the result in the second image based on how Revit "typically" works.

But what if what you were looking for was slighting different, what if you wanted the part of the solid that is being subtracted? Normally in the Revit "world" you would say you need to create a void that is on the "outside" rather then just a spehere, to get the result in the third image.

What is I told you that you can create the condition with the same spherical void! You might say, what! How! Well, its seems that normals sometimes do matter in Revit.

To achieve the result in the third image its is all about how you draw the arc that creates the sphere. In the first example the arc is drawn counter-clockwise from the "top" of the axis to the "bottom" of the axis. To get the result in the third image the arc must be drawn clockwise from "bottom" to the "top" of the axis. In this case the differing result is because the normal(s) of the surface that make the void are different based on the direction of the arc, which is controlled by how you draw it.

An interesting little "feature" in Revit/Vasari (to be honest I did this in Vasari), your mileage may vary on what you get depending on what you're doing, but it could be handy and it shows that it pays to pay attention to what direction you draw your lines, even in Revit!

Vasari Experiment

So, "everyone" (not really sure who everyone is, but I know they're out there) "says" (at least I think so) that the Massing environment is not useful to them, because they don't do twisty curvy buildings, they only do straight boring buildings. Well, I have a little example of a "boring" little house:

This house actually is already built (and its not quite so boring), but thats not the point here. The owner of said house was interested to know if the location (Bolton VT) would likely support the use of Solar Panels for domestic hot water and potentially some heating. The house is also located in valley, but generally has good southern and western exposure. So the task was simple, do a quick mock-up to get a sense of total sun exposure at the worst time of the year to validate what we intuitively suspected.

So how did I get 5 square miles into Vasari? Sketch-Up & Google Earth of course! At the scale I was operating at, Sketch-Up's rough approximation of terrain from Google Earth was more then sufficient, and Sketch-up's DWG export go us what we needed. I supposed if I was really enterprising I could've placed points on the intersections, then made splines, and then created smoother surface. But really, who has that kind of time!

Once I had my terrain a simple analysis confirmed what we were pretty sure we already knew... Plenty of sun in the afternoon, not much in the morning.

Hacking Vasari

The Best of Both Worlds part II

So I've tooled around with Vasari a little bit, in some ways it is quite liberating because it is so "lite" in other ways it is quite limiting, for obvious reasons.

One of my favorite commands in Revit is "Create Similar". It makes it so easy to create something in canvas without having to go use the Type Selector or do much else, click on the item and use the keyboard shortcut (CS), or right click and choose "Create Similar" from the context menu.

One of the interesting things about Vasari is that its still "Revit" and while they've turned off any number of tools and what not, a command like "Create Similar" is so ingrained, and so low level that it can't really be turned off (not to mention it has its uses in any context in Revit). Its almost like the "sleep" command Data used in TNG to stop the Borg from attacking Earth. Who would think that such a minor little command could wrought such interesting possibilities!

Anyway, if don't have a full blown version of Revit Architectture, but you download Vasari, fear not! Grab a Revit file from any number of locations (AUGI, Revit City, Autodesk) that already has some walls, floors, doors, whatever created in the file, and go to town! You can use Create Similiar to make your own elements, all without the convenience of the commands found in the Ribbon. Now this is not to say you'll be able to do everything and anything, but I do think it would be possible to do some fairly rudimentary modeling in Vasari with "typica"l Revit elements.

If you were really enterprising, you could create a "template" file for yourself with a bunch of elements created in an orderly fashion, that can be used with the CS command to begin modeling what ever you want.

Happy explorations!