Thursday, April 20, 2006

Where is my Zero, Zero ?

This quick REVIT Building 8.1 tutorial explains how to identify, where to locate and how to move the model 0,0 in a plan view. This tutorial does NOT apply to the family editor. The first thing this tutorial comes with is a warning!!. Do NOT arbitrarily start moving the 0,0 location in a project. Especially if it is a linked file. Use a test project until you get a handle on it. Also, these quick tips only involve locating and moving the 0,0 location of the project. We will not discuss at this time actually ‘relocating the project’. There is a difference between moving the 0,0 and moving the actual model to a new location. If you have the freedom to do so it is far easier to move the 0,0 to where you want rather than moving the Model to the 0,0. Make sense right ? Move the 0,0 to the mountain rather than moving the mountain to 0,0. If all you need to do is make a certain point in the project 0,0 then you can move the 0,0 to that point similarly to as if you move the UCS in AutoCAD. Sometimes this comes in handy when trying to coordinate the building position with the property lines etc. If the model is linked to other files you need to be careful of what you do and you need to understand a little more about 'shared coordinates' and 'project north'. Having said that it’s actually simple to locate and move the 0,0 origin. The 0,0 is where the N / S zero and the E / W zero intersect, right? TIP: I tend to place and use reference planes when doing this type of activity. TIP: Try naming a reference plane in it's properties. Then click on it and the name will show up. Lets start by looking under the ‘Tools’ pull down menu and go to ‘Shared Coordinates’ tool. We will use the ‘’Report Shared Coordinates’ and the ‘Specify Coordinates at a Point’ tools. Lets have a look. Start the ‘’Report Shared Coordinates’ tool and you are prompted to ‘select a shared reference to display it’s shared coordinates’. (Read the REVIT status bar on the lower left of the screen). Depending on what you selected and where you select it will depend on what is reported. Try hovering over different object geometry and then selecting. Try hovering over a reference plane or wall near the end point. There is a snap point at geometry end points. This will return the N / S and E / W and Elevation of the geometry. You can think of the East / West as X, North / South as Y and Elevation as Z. Note at the top of the screen the read only information. Also note that if the object or face of object you select runs E / W it will only return a N /S number and visa-versa. Think about it. It makes sense. So the ‘Report Shared Coordinates’ reports read only information. Next, start the ‘Specify Coordinates at a Point’ tool to both ‘report’ and ‘alter’ coordinates. Once again, ‘what you select’ and ‘where you select it’ will depend on how this dialog reports. Experiment with different object types and locations along that geometry. I have selected a diagonal reference plane to get the above information. TIP: As usual use the Tab key to toggle through adjacent geometry. We are only going to discuss the 'New Coordinates' section of this dialog box. You can click into the appropriate field and change the numbers if it allows you to. Be aware that all points are relative and will then report accordingly. If you change the N/S or E/W coordinates of an object do not expect anything to actually move when you are done. It simply makes that point the new coordinates and the rest of the model is all relative to that new point. If you are linking this model and using shared coordinates it will most likely move in that file so be aware !! TIP: Use the Esc key (or cancel button ) instead of clicking Ok to keep Looping back into this Reporting tool. Otherwise you have to go back to the pull down menu each time. Example scenario: I want the lower left corner of my building to be at 0,0. This is how you can do it. 1. Open the plan view and zoom into the corner wall geometry. 2. Start the ‘Specify Coordinates at a Point’ tool and select the Horizontal wall anywhere on the bottom face. 3. Set the North / South to be 0 and OK 4. Start the ‘Specify Coordinates at a Point’ tool and select the Vertical wall anywhere on the Left face. 5. Set the East / West to be 0 and OK 6. You are done. The lower left corner of the intersecting walls should be at 0,0. 7. Nothing will actually move but all the x,y points in the model have now changed. TIP: Try selecting a wall near an endpoint vs midspan. Notice the different info. reported. You may be able to change both the x and y in the same dialog if you get the right endpoint You could also do the same example scenerio as above but use Property Lines instead of Walls. Important The bottom of the ‘Specified Shared Coordinates’ dialog has a section labeled ‘Angle from Project North to True North’. Views can be oriented to ‘Project North’ or ‘True North’. This is a separate lesson all by itself. Please refer to the free CADCLIP titled True North – Project North at DG CAD for all the details on this process. Well, I hope this is of use to some of you. Practice...practice....

3 comments:

Tim Gibson said...

Fantastic explanation. I didn't realize you could actually cahnge the location of the origin!

Daryl said...

I KNOW ! neither did I until I started digging around. Being an old autocad type it's just something that gets drilled into your head. It's the first thing you learn.

I've been using REVIT for two years and never figured it out until two days ago. Didn't have to...

I will also do a blog on locating 0,0 in a family. That I did know. It's completely different.

ddumping said...

This site is one of the best I have ever seen, wish I had one like this.
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