On Land

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At Rill Architects we run ArchiCAD on macOS. If you work at Rill, this is your stuff. If you don't, but you work in ArchiCAD, you may find something interesting. Anybody else, I don't know.
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Every viewpoint has a name and an ID. The name is important and is often used for output. The ID is never used for output, but wherever possible we use the ID to help organize the project map and view map.

Info Box name/ID
For viewpoints with with a marker, the name and ID appear in the Info Box and settings dialog. This applies to section, elevations, details, and interior elevations.

Properties in Navigator
For all viewpoints, the name and ID appear at the bottom of the Navigator under the Properties heading. Viewpoints with fixed IDs, such as stories, will have the ID field in gray.

The behavior of IDs varies among the viewpoint types, so here's a cheat sheet.

Story IDs
Stories have unique, fixed IDs based on the order of stories. They are ugly. We ignore them.

Section IDs
Section and Elevation IDs are created by the user, and they need not be unique, but the name/ID combination must be. (If you try to create a section/elevation with an identical name and ID, AC will automatically append a number to the ID.) Sections and elevations should have an ID roughly corresponding to their sheet number. Building elevations and sections get A2-1, A2-2, etc., and wall sections get A3-1, A3-2, etc. For sections, add a letter to indicate the direction the section is facing. Don't put the direction in the name. For 'Junk' sections, used for modeling support and not for output, the ID should be xn where n is a number. Junk sections x1 through x4 are placed in the template. (Yes, junk sections should usually be sections, not elevations.) So you end up with a section list of output viewpoints at the top, followed by all the junk.

Interiors IDs
Interior Elevation IDs should start with A5. I like to use the ID to sort the interiors by story: Basement is A5-0, first floor is A5-1, etc. Like the sections and elevations, the actual output sheet may differ. The sorting is to help you know where to look in the view map.

Detail IDs
Detail IDs need not be unique. (In AC10 and earlier, they had to be.) Still, it's a good habit to make them distinctive. I find it helpful to use the detail ID to give the 'category' of detail. For example, a bunch of eave details will have IDs of Eave01, Eave02, etc. The assembly type details have Type01, Type02, etc. Structure detail IDs start with S_ followed by a number. For all details, the name should be presentable for the automatic drawing title.

Worksheet IDs
Worksheets are a new, mostly redundant viewpoint type in AC11. We could easily live without them, but since they exist, we park all the straggly non-detail drawing things there. There aren't enough worksheets in a typical project to worry about sorting the list, so I recommend leaving the ID blank and just using the name.

The primary Schedules have an ID to sort them to the top of the menus. Incidental schedules don't need IDs. This may change.

Cameras and paths have unique IDs that can't be changed.

Summary: Viewpoint IDs are not used for output, so use them to help sort the lists. Names are used for output: Use the name you want to see on the paper.

The IDs that do matter for output are those of the layout book items; subsets, layouts, and drawings.

Drawing IDs are usually generated by the layout, either by the grid or the order of drawings in the layout book tree.

Layout IDs are usually generated by the subset.

Subset IDs are set by the user, and the subset ID becomes part of the layout ID.

Views also have IDs, but they should typically inherit the viewpoints' IDs, so the lists will appear the same to us. All view IDs can be customized or set to 'None', but you can usually just leave them be. In the templates, I have deleted all the IDs for story (plan) views, because stuff like "-1. Basement" looks idiotic.