feature focus
Revit Architecture orientation, you can use the “Specify Coordinates at a Point” tool or acquire coordinates from the aforementioned “Origin” DWG when located at the Project origin. (See Figure 3)
Figure 2: DWG file linked using Auto - Origin to Origin
your office’s project templates so everyone can easily identify the Project Origin. (See Figure 2)
Where is my Shared Coordinate system Origin? When you start a project from the default template, you will find that there is already a location called “Internal”. In contrast to Autocad, a Revit project always has a Location, whereas a DWG does not need to contain a named UCS. “Internal”’s Shared coordinate origin and orientation coincide with those of the Project Coordinate system. It is important to note that changes to the Shared Coordinate system are automatically saved to the current Location. If your Shared coordinate system has been modified and you want to control the location of the Shared origin and
I’m not following what you mean by “acquire coordinates”. Could you elaborate further? There are two ways to modify a Shared Coordinate system. You can do that by Acquiring Coordinates from a DWG file/ RVT project, or you can Specify Coordinates at a location. Typically, we would use the Acquire tool when linking in a DWG survey or a Site RVT project, after positioning and orienting the link properly in relation to the building. This procedure is the most “transparent” and does not require us to be bothered with origin locations. When you acquire coordinates, the host project’s Shared Coordinate system is aligned with the DWG’s WCS or to a UCS that Revit recognizes, or to the linked RVT project’s Shared Coordinate system. I tried this but Revit says that it cannot acquire coordinates from a model with multiple named locations. What’s happening? If this happened when acquiring from a DWG, then Revit found multiple UCS’s that it recognizes and doesn’t know which one to use. You can acquire from DWG’s that have only one recognizable UCS. In the absence of such UCS, the WCS will be used instead. The same will happen with a linked RVT project containing multiple named locations. In these cases, you might have to manually specify coordinates at a point to locate your Shared Coordinate System. There is however another way to acquire coordinates in such situations. Select the link, go to its properties and at the bottom, click that little button on the right (probably it is saying “<Not Shared>”). In the “Share Coordinates” dialog, click the “Change” button and select the UCS or Location you want to record as your host project’s Shared coordinates. Then select the “Acquire” option and click “Reconcile”. Since Revit is also not capable of publishing coordinates from projects containing multiple locations, this technique will help you achieve that goal too. What’s all this about publishing coordinates? Acquiring forces your project’s shared coordinate system to align to the link’s UCS or current Location. Publishing does the inverse: it takes your shared coordinate system and forces your link’s UCS or current Location to align to it. When you publish, you need to save these changes to your link through the Manage Links dialog if you want to retain them, which will modify the linked DWG or RVT. If you forget, Revit will present you with the option to do so when closing your project.
Figure 3: DWG file linked using Auto - Origin to Origin
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Earlier you mentioned that Revit recognizes certain UCS’s in a DWG link. How does it do that? Revit recognizes a UCS in a DWG if the name is prefixed with “REVIT60-”. So for example if you name a UCS as “REVIT60spring_2009