Monday, March 4, 2013

The Elusive Origin aka The Original Origin aka Not the Current Origin

I must admit:  It has been a few years since i ran up against this problem, even though i was reminded of it while explaining to someone interally why there are THREE origins in Revit:  Shared, Project, and Relative.
Alas, this isnt a post on Shared Coordinates, just a small reminder about another gotcha that appears in the Family editor:  The Original Origin (The Elusive Origin) versus the Real Origin.  If you know me well (or if you dont know me at all), you know one of my hundreds of obsessions is Door Content, and how it affects Architects abilities to document efficiently... Of course, the bigger picture is:  What does it REALLY mean to document doors correctly for buyout and installation?  But ill check that at the door.  Todays is a smaller issue. Im redoing the CW Doors in addition to the Regular doors to make some changes:
1.  Parent Families by Action.  (Most people do this, my last library iteration was a bad choice. The "action" definition was part of the Panel Type.  Horrible idea.  I have to own that).
2.  Panel Typology including Materiality (not finish) at the Type Level, not instance.  Less fields in the "door schedule" as more is defined by Type of Panel.
3.  More options to reflect the real world.  This meant adding in the potential for CW/SF doors to have a Frame inside them as well.  Sometimes Doors in Storefront Systems get an additional frame jamb and head aside from the surrounding mullions, and i wanted that capability.  So the new options looked like this. (You can see the door at left has the frame).
But we all know the way Doors are Curtain Wall Panels in Revit means you get two choices: 
1. Door Panel Sizes flex with Curtain Wall Grids, runs risk of Door Schedule showing wacky Dims.
2. Door Panel Locations flex with Curtain Wall Grids, runs risk of gaps in between the Doors.

I personally prefer the latter.  Reason being BOTH infuriate Project Teams, but the Door Schedule is sometimes already seen as a WonderWall of data that is more like PowerBall and less like steadfast decisions.  So any chance i can get to make the schedule not go nuts, i "jump in it."  But, i also have Check Value Reporting Parameters in our Curtain Wall Doors.  They tell the user how much they have to adjust the CW grids to make the model AND the schedule legit.
While working on my new CW Doors to finish out the Door Library, i found this beauty:  A rogue 7/128" hanging out somewhere between the CW Grid dimensions (which are correct:  All dims and units are rounded to 1/256" in our files), and the Reporting Parameter dims of the Doors.  Nicey nice. First i tore through the Door (CW Panel) itself, assuming i had missed something minor... But there isnt even any complex math in it.
So then i realized whatever it was had to be in the Mullions of the CW/SF in the Project.  Joy. Although it drives people crazy, we have a LOT of Mullion Types, and a lot of Profiles, so we can accurately model varying shim spaces, glass pockets, etc.  So i opened up the Mullions, and re-certified that the Origin-defining Ref Planes were locked centered.
Then i remembered this minor bit of stupidity that hit me back in 2009, when i was making NCS Compliant Section Heads in New York State:
That Revit sometimes forces you to use the Original Origin of a Family, and not the currently defined origin.  In that regard, its sort of like Relative versus project.  And in the Profile Family editor, you cant see origins (aside from ref planes), so i pulled the old school "Insert CAD drawing with an X at the origin OtO, and see where it comes in."
Sure enough, it wasnt sitting pretty on the 2 ref planes that were defining my origin currently... It was the ever elusive 7/128" off that my Curtain Wall Panels were reporting.
Thankfully its got an easy (albeit stupid and shouldnt be necessary) fix:  Picking up everything in the family and moving it towards to "original" origin by the offending amount.  In this case, 7/128".  I hadnt seen this issue in a number of years, so i forgot that back in the day it caused a few issues for me where Section Heads had a gap from the system Witness Line, and tags were somehow offset from the leaders that were supposed to be touching them.
It still feels a but odd that i can have Reference Planes Defining the origin and have them not be the Finite Origin that all things referencing that Profile are, but i guess its just another day with Revit.  
Having solved that riddle, everything now appears to be playing by the rules.  I cant say my users will be any more happy to have these CW Doors over the old ones (they are Revit Curtain Walls, after all), but they will be more functional, and will more accurately represent what i would like them to be for Documentation and Construction.
They certainly havent gotten any more difficult to use, even if the CW Doors are a "wash" with the old ones.  These are compatible with our new Wall Hosted Doors, which (i think) are worlds better than the last set. 
At the very least, i got to have a nice stroll down memory lane relearning things i forgot i used to know a couple of years ago... And now we can all make jokes about the Elusive O... O is for Origin.

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