Associative elevation dimension to a beam top on Interior Elevation. Hand tool keeps it, API cannot.

rabo44ka — Wed, 23 Sep 2026 20:10:51 GMT

Archicad 26 RUS, C++ API. We place an elevation dimension (API Dimension ID, ed dimForm = 7) on an Interior Elevation window.

A hand-placed height on the top of a Beam stays associative: it follows the beam if the beam is moved. After Element Get / GetMemo that same mark is empty: defStaticDim = 0, fixedPos = 0, but API Base type and guid are empty, inIndex = 0, and node id / node status / node typ are zero. Element GetLinkFlags returns APIERR LINKNOTEXIST. There is no documented field that names the beam.

The same writer keeps other elevation heights.

Library object (socket): live SectElem (type 29), inIndex = 0, node id = 50000500, node typ = 1100.

Slab top: live SectElem, node id = 4, node status = 16, node typ = 2100, parent API Slab ID.

Those match what Get returns on a hand sample. For the beam, Get on the hand sample shows nothing to copy.

We tried four writes. All are closed.

Empty base, as the hand readback. Create stores the mark as static.
Beam drawing (SectElem) hotspot. After create: live. After the undoable command commits: the element is gone (APIERR BADID). commandErr = 0.
Beam drawing node. Same: live inside the undo step, discarded at commit.
Model Beam (API Beam ID, type 3) at the right edge and top Z. Same: live after create, BADID after commit.

A tag / user-data write is not the cause. We skipped it. Create outside CallUndoableCommand is refused (APIERR REFUSEDCMD). We did not copy the slab node 4 onto the beam. That would not be a documented bind.

Official API Base docs say node status and node typ are for internal use, reserved for section dim. There is no published way to obtain node id for a beam. No Neig-to-DimElem helper. Community reports since 2015-2017 describe the same class: elevation and section dimensions to projected elements disappear, or stay only when node id is forced.

Questions:

Is an associative elevation dimension to a Beam top on Interior Elevation supported through the public API?
If yes, which API Base must we write: type, guid of model vs SectElem, inIndex, node id, node status, node typ?
If the hand tool keeps a hold that Get / GetMemo does not expose, how should an add-on recreate it? Or is that hold intentionally internal and not available to third-party code?

We can provide a small PLN and the after-create / after-commit dumps.

Operating system used: Windows

topic Associative elevation dimension to a beam top on Interior Elevation. Hand tool keeps it, API cannot. in Archicad C++ API

Associative elevation dimension to a beam top on Interior Elevation. Hand tool keeps it, API cannot.