Use IfcMapConversion.Scale as the source of truth for converting map coordinates to metres, instead of deriving that scale from IfcProjectedCRS.MapUnit. Bump the sidecar version because cached georef matrices and unit scales may differ under the new interpretation.
Generated with the assistance of an AI coding tool.
When the user adds a model into a fresh, untitled federation that still
has the default (0,0,0, no rotation) FederatedFalseOrigin, derive an
origin from the first instance's placement_transformation (lifted
through CoordinateOperation when enabled) and the helmert grid-north
baked into ModelGeoref::coordinate_operation_meters. Multi-file batches
naturally settle: whichever load finishes first anchors the federation,
the rest see a non-default origin and skip. Saved .ifcfeds keep their
authoritative origin.
Adds Placement.{h,cpp} (port of util/placement.py — a2p,
get_axis2placement, get_local_placement) so Geolocation no longer needs
its own anonymous getAxis2Placement, and xaxis2angleDeg in Geolocation
mirroring util/geolocation.xaxis2angle.
SceneLoader captures the first instance's placement_transformation from
either the sidecar's InstanceCpu[0] or the streamer's first
InstanceChunk, so the guess works on both load paths without re-reading
the IFC.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
helmertMetersFromParameters builds the helmert transformation as a
meter-input/meter-output 4x4 directly from parsed parameters, bypassing
autoLocal2Global's normalisation step. This preserves
IfcMapConversionScaled.FactorX/Y/Z in the rotation block so the factor
applies to placement translations when the matrix is precomputed
per-model and composed with placements at upload time. For ordinary
IfcMapConversion (factor = 1) this is bit-identical to
autoLocal2Global; only diverges on rare surveyed models with non-unit
factors, where it is the only correct behaviour.
getMapUnit returns IfcCoordinateOperation.TargetCRS.MapUnit so callers
can resolve the unit-to-metres scale via Unit.h's siScaleFromNamedUnit.
autoLocal2Global is unchanged — kept as a clean port of the python
ifcopenshell.util.geolocation reference impl for one-shot
project-units-in / map-units-out callers.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Mirrors ifcopenshell.util.geolocation: HelmertTransformation parameters
(IfcMapConversion / IfcMapConversionScaled / IfcRigidOperation, plus
IFC2X3 ePSet_MapConversion), get_wcs from IfcGeometricRepresentationContext,
local2global, and auto_local2global. Lives in src/ifcviewer/ for now;
will move out when ifcopenshell.util is ported to C++.
Not yet wired into the streamer. A subsequent commit fixes the
unit handling for the iterator's meter-by-default output.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Dion Moult