Four review findings, all measured by the reviewer on AutoCAD 2026:
1. ucs_list and the ucs_restore('world') CMDACTIVE guard read
app.GetVariable, but GetVariable is an AcadDocument member — the tool
was dead live and the guard's swallowed read forced cmd_active to 0,
sending `_.UCS _W` into any open prompt. Both read the document now,
and a failed CMDACTIVE read refuses instead of proceeding. The fake
app in tests/test_views_ucs.py has no GetVariable any more, so the
old code cannot pass.
2. view_named_save defaulted from doc.ActiveViewport.Center/Height/Width,
which does not track the display (it answered the initial view after
`_.ZOOM _C 5,6 20`). The current view is VIEWCTR / VIEWSIZE at the
SCREENSIZE aspect — what `-VIEW _S` records (width 40.267 for height
20). The fake viewport is deliberately stale so a read of it fails.
3. view_named_restore wrote Center/Height/Width into the AcadViewport;
AutoCAD anchors the lower-left corner and widens to the display
aspect, landing a 10x20 view at (5, 6) on VIEWCTR (20.134, 6). It now
zooms the saved rectangle (app.ZoomWindow), which centres and fits
like `-VIEW _R` (VIEWCTR = saved centre, VIEWSIZE = max(h, w/aspect)),
reports `applied: "zoom_window"` and reads VIEWCTR / VIEWSIZE back.
Headless the same reconciliation moved the centre whenever the
*Active VPORT's aspect was rewritten from w/h (even the 1.34 default
opened at x = 11.734): the aspect the file carries is left alone —
it is the display's, written by AutoCAD at save — and the window is
fitted into it; the payload adds `vport_height` / `aspect_ratio`.
4. layer_state_restore set ActiveLayer before the loop and outside the
try; AutoCAD refuses to make a frozen layer current, so the spec's
own save → freeze → restore path raised an opaque COM error with
nothing applied. When `frozen` is being restored the state's current
layer is thawed first; the write is wrapped and a refusal lands in
`warnings`. The fake document and layer now model both refusals.
Live AutoCAD was not running in this round (GetActiveObject failed, no
acad process), so the fix is measured against the reviewer's numbers,
not re-measured.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
An unnamed UCS (UCS Origin / 3P without saving, the common kind) has an
empty UCSNAME exactly like WCS does, so both engines answered
`current: world` while the drawing was not in WCS — verified live on
AutoCAD 2026 (`_.UCS _O 10,10,0` → UCSNAME="" WORLDUCS=0) and on the DXF
it writes ($UCSNAME='' $UCSORG=(0,20,0)). A silent wrong value.
- COM: a named match still wins; otherwise WORLDUCS (AutoCAD's own answer)
decides, and WORLDUCS=0 appends a `name: None` row built from
UCSORG/UCSXDIR/UCSYDIR.
- ezdxf: the same rule against $UCSORG/$UCSXDIR/$UCSYDIR via the new
`engineering.environment.ucs.is_world_axes`; a stale $UCSNAME falls back
to the frame instead of leaving no row current.
- Server `ucs_list` result: `current` is null for an unnamed UCS (never
`world`), plus `current_unnamed: bool` so null is unambiguous.
- Tests: helper, headless (unnamed row, stale name, and the exact AutoCAD
DXF over the wire), and COM fake reading WORLDUCS + the frame variables.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
ezdxf's VIEW default is direction=(1, 1, 1) — an isometric view — so every
named view the headless engine wrote to disk was oblique while the tool
claimed to store the plan window of center/height; AutoCAD restored it in
that DCS. view_named_save now writes direction (0,0,1), target (0,0,0) and
view_twist 0 explicitly. view_named_restore copies direction/target/twist
from the VIEW into the *Active VPORT instead of flattening a foreign
oblique view to plan, reading the attributes the way the file carries them
(ezdxf forces those tags on export). Measured live on AutoCAD 2026:
Views.Add already creates a plan view, so the COM path only gains a note.
Tests: the VIEW entry and the reopened DXF assert 11/21/31 = 0/0/1 and the
target; a hand-built oblique, twisted VIEW restores its orientation into
the VPORT and a tool-saved view puts it back on plan.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
Layer states are ACADMCP_LAYERSTATES XRECORD chunks (<= 255 ASCII chars each),
in the file and not in AutoCAD's Layer States Manager. Headless view restore
writes the *Active VPORT (ezdxf's header has no $VIEWCTR; measured). UCS is
stored and made current; tool coordinates stay WCS.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
