Both overlays draw the same three positive-axis rays (origin → +X / +Y
/ +Z) — one screen-space-thick-line shader, one vertex buffer, one
bind group layout. The vertex stage transforms each vertex as
`mvp * (origin + position * arm)` so the same primitive serves both
modes:
corner: viewport set to a 110×110 px box in the bottom-left,
camera-orientation ortho MVP, origin=0, arm=1.
pivot : full viewport, main view-proj, origin=camera_target,
arm = 30 logical px in world units.
Pipelines
axis_pivot_pipeline_ — MSAA + depth LessEqual (α=1)
axis_pivot_xray_pipeline_ — MSAA + depth GreaterEqual (α=0.30)
axis_corner_pipeline_ — resolved surface, no depth, sampleCount=1
Pivot renders inside the main MSAA pass after geometry (depth
interaction); corner renders on the resolved surface after the edge
silhouette pass so the laplacian can't darken its lines. The pivot's
two passes — x-ray first then visible — give an occluded-side hint
matching GL's renderPivotIndicator.
Screen-space thick lines
WebGPU has no lineWidth, so each axis is a 2-triangle quad expanded
by `line_width / 2` pixels along the screen-space perpendicular in
the vertex shader. Every vertex carries BOTH endpoints (start, end)
plus `t ∈ {0,1}` and `side ∈ {-1,+1}` so the direction is computed
consistently as `s_end - s_start` regardless of which end the vertex
sits at — an earlier "this vertex vs the other end" formulation
flipped sign at the end vertex and produced a bowtie.
Analytical AA
|side_t| ∈ [0,1] is the perpendicular distance from the line centre.
`smoothstep(1-fwidth, 1, |side_t|)` gives a 1-pixel coverage falloff
at the long edges — gizmos read cleanly even on the resolved-surface
corner pass which has no MSAA.
Pivot visibility
- orbit / pan drag press → on, release → off
- wheel zoom → on with 600 ms afterglow via QTimer
Pole fallback for the corner gizmo's lookAt mirrors buildViewProj's
identical fix (swap Y-up when |pitch| ≥ 89°), so top/bottom standard
views don't degenerate.
Tracked under task #59.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
IfcOpenShell
IfcOpenShell is an open source (LGPL) software library for working with Industry Foundation Classes (IFC). Complete parsing support is provided for IFC2x3 TC1, IFC4 Add2 TC1, IFC4x1, IFC4x2, and IFC4x3 Add2. Extensive geometric support is implemented for the IFC releases IFC2x3 TC1 and IFC4 Add2 TC1. Extending with support for arbitrary IFC schemas is possible at compile-time when using C++ and at run-time when using Python.
In addition to a C++ and Python API, IfcOpenShell comes with an ecosystem of tools, notably including IfcConvert (an application to convert IFC models to other formats), Bonsai (an add-on to Blender providing a graphical IFC authoring platform), and many other libraries, CLI apps, and more. Support is also provided for auxiliary standards such as BCF and IDS.
For more information, see:
Development is sponsored through your generous donations!
Contents
| Name | Description | License | Service |
|---|---|---|---|
| bcf | Library to read and write BCF-XML and query OpenCDE BCF-API modules | LGPL-3.0-or-later | |
| bonsai | Add-on to Blender providing a graphical native IFC authoring platform | GPL-3.0-or-later | |
| bsdd | Library to query the bSDD API | LGPL-3.0-or-later | |
| ifc2ca | Utility to convert IFC structural analysis models to Code_Aster | LGPL-3.0-or-later | |
| ifc4d | Convert to and from IFC and project management software | LGPL-3.0-or-later | |
| ifc5d | Report and optimise cost information from IFC | LGPL-3.0-or-later | |
| ifcbimtester | Wrapper for Gherkin based unit testing for IFC models | LGPL-3.0-or-later | |
| ifcblender | Historic Blender IFC import add-on | LGPL-3.0-or-later* | |
| ifccityjson | Convert CityJSON to IFC | LGPL-3.0-or-later | |
| ifcclash | Clash detection library and CLI app | LGPL-3.0-or-later | |
| ifcconvert | CLI app to convert IFC to many other formats | LGPL-3.0-or-later* | |
| ifccsv | Library and CLI app to export and import schedules from IFC | LGPL-3.0-or-later | |
| ifcdiff | Compare changes between IFC models | LGPL-3.0-or-later | |
| ifcedit | CLI wrapper for ifcopenshell.api IFC model mutation functions | LGPL-3.0-or-later | |
| ifcfm | Extract IFC data for FM handover requirements | LGPL-3.0-or-later | |
| ifcmax | Historic extension for IFC support in 3DS Max | LGPL-3.0-or-later* | |
| ifcmcp | MCP server for querying and editing IFC building models | LGPL-3.0-or-later | |
| ifcopenshell-python | Python library for IFC manipulation | LGPL-3.0-or-later* | |
| ifcpatch | Utility to run pre-packaged scripts to manipulate IFCs | LGPL-3.0-or-later | |
| ifcquery | CLI tool for querying and inspecting IFC building models | LGPL-3.0-or-later | |
| ifcsverchok | Blender Add-on for visual node programming with IFC | GPL-3.0-or-later | |
| ifctester | Library, CLI and webapp for IDS model auditing | LGPL-3.0-or-later |
The IfcOpenShell C++ codebase is split into multiple interal libraries:
| Name | Description | License |
|---|---|---|
| ifcgeom | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcgeom_schema_agnostic | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcgeomserver | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcjni | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcparse | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcwrap | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| qtviewer | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| serializers | Internal library for IfcOpenShell | LGPL-3.0-or-later* |