PluginHostApi.cpp had grown into one TU holding the module entry point plus
three unrelated domains (presets, model/mesh graph, app access), and
PluginHostSlicing.cpp mixed ownable geometry value types with the
non-owning live print graph. Reorganize the orca.host surface into
plugin/host/ with one registrar per domain:
- PluginHost.hpp/.cpp entry point (replaces PluginHostApi)
- PluginHostBindings.hpp internal per-domain registrar declarations
- PluginHostGeometry.cpp BoundingBox, Point, Polygon, ExPolygon + ndarray parsing
- PluginHostMesh.hpp/.cpp TriangleMesh snapshot (own TU ahead of planned
mesh construct/mutate APIs)
- PluginHostPresets.cpp Preset, PresetCollection, PresetBundle
- PluginHostModel.cpp scene graph: Model, ModelObject, ModelInstance, ModelVolume
- PluginHostApp.cpp Plater + plater()/model()/preset_bundle() accessors
- PluginHostSlicing.cpp live print graph only, now with a single lifetime story
- PluginHostUi.hpp/.cpp moved unchanged
PluginBindingUtils.hpp stays at plugin/ root: it is shared with pluginTypes/
and tests, not host/-specific.
No Python-visible change: same submodules, class names and docstrings.
Verified with slic3rutils and fff_print suites.
Introduces a plugin capability that runs Python at the seams of Print::process(),
letting a plugin read and rewrite slicing state as it is computed.
- New slicing_pipeline_plugin config option; selected plugin refs are serialized
into the print manifest.
- Print gains an injectable hook fired at each pipeline step (posSlice,
posPerimeters, posInfill, ...). It is a no-op when unset, fires only on genuine
(re)computation, and never on the use-cache path.
- orca.slicing submodule: SlicingPipelineCapabilityBase plus a trampoline and a
Step enum. Capabilities read the live graph through zero-copy int64 numpy views
(contour/holes geometry with unscaled coordinates, flattened toolpath data) and
edit it through 2D-geometry mutators with cache-invariant refresh.
- GUI dispatcher runs capabilities during slicing under the GIL, turns plugin
errors into slicing errors, honors cancellation, and adds the plugin picker.
- Ships the InsetEverySlice sample plugin and binding/hook tests.
