Non-Planar controls¶

The panel is deliberately first in Prepare: it states the product decision before conventional Process values. It is expanded by default.

Control-by-control honesty¶

When Enable is off, all dependent controls are disabled with the visible reason Enable Non-Planar first. Values may remain displayed, but they do not imply that the engine consumed them.

Planned parameter object¶

PROPOSED — the new numeric/policy fields travel together in an additive POD:

NpsNonPlanarParams
  maxSurfaceAngleDeg
  maxAmplitudeMm
  thicknessEnvelopeMm
  collisionRadiusMm
  collisionHeightMm
  detectionMode
  seamPolicy
  reserved[8]

The reserved tail follows the additive ABI policy. The exact binary layout is a developer contract; users see units, ranges, and disabled reasons rather than ABI field names.

Region detection and painting¶

flowchart TD
  E["Enable Non-Planar"] --> M{"Detection mode"}
  M -->|Auto / Full| D["Detect regions"]
  M -->|Paint| P["Enter paint mode"]
  D --> L["Region list: auto badge"]
  P --> B["LMB paint · Shift+LMB erase · Esc exit"]
  B --> C["Commit strokes"]
  C --> L2["Region list: painted badge"]
  L --> O["Optional per-region override"]
  L2 --> O
  O --> R["Re-slice"]

Detect¶

PROPOSED — Detect is enabled only when a model is loaded and Non-Planar is on. It runs detection with the panel parameters, then replaces/updates the region list. Every row shows:

• region name/id;
• auto or painted source badge;
• affected plate/object;
• inherited versus overridden values;
• a focus action that opens the Regions inspector.

Detection failure keeps the prior list and reports the engine error in status and Activity. The UI does not show a fake successful empty list.

Paint¶

PROPOSED — Paint can be entered from the panel, toolbar, or B:

The viewport uses existing mesh geometry queries for hit geometry (GetVertexPositions / GetTriangleIndices exist at src/Nps.EngineHost/NpsAbi.cs:309–316). The paint-stroke commit and region-mask overlay are PROPOSED.

Regions inspector¶

PROPOSED — the Regions tab is the full editor. It mirrors the compact Prepare list and adds focus, override, delete, and re-detect actions. Edits mark the current generated path dirty; they do not recolor an old path as if it had been regenerated.

Planned non-planar overlays¶

The three ids must enter the engine overlay registry and surface through the existing GetSupportedOverlayIds export before the dropdown presents them. GetSupportedOverlayIds exists today (src/Nps.EngineHost/NpsAbi.cs:467–474), but the non-planar ids do not.

Collision-critical colors come from the existing severity palette; the heatmap remains viewport content rather than a new chrome theme.

Collision finding → fix loop¶

PROPOSED — collision risk is actionable rather than decorative:

flowchart LR
  C["Collision-risk critical band"] --> F["Select collision finding"]
  F --> Z["Focus layer / move"]
  Z --> Q{"Fix scope"}
  Q -->|Global| G["Raise radius / height clearance"]
  Q -->|Local| P["Paint region + override"]
  G --> R["Re-slice"]
  P --> R
  R --> V["Replay and verify band / count"]

1. Select collision-risk in Preview or Simulate.
2. Click the critical marker/finding to focus its layer and move.
3. Return to Prepare.
4. Raise global clearance, or paint a local region and set an override.
5. Re-slice; the dirty banner clears only after successful generation.
6. Confirm the band downgrades and the Critical count falls.

HOW IT IS — selecting a current finding already focuses simulation state (src/SlicerApp/MainWindow.axaml.cs:679–738; src/SimulatorApp/MainWindow.axaml.cs:665–727). Collision fields, non-planar category, fix controls, and severity-count feedback are PROPOSED.

Stair-step verification¶

PROPOSED — Ghost Compare verifies the visual result against a planar baseline:

1. Preview the non-planar result with nonplanar-amplitude active.
2. Turn on Ghost Compare.
3. The host snapshots the active path, regenerates a baseline with enableNonPlanar=0, and snapshots that baseline before another generation.
4. The baseline renders dimly beneath the non-planar path.
5. Restrict the layer band and scrub curved surfaces.
6. Confirm the non-planar path reduces the visible stair-step transition.

The snapshot order is mandatory because engine move pointers remain valid only until the next load/generate/parse operation (src/Nps.EngineHost/EngineSession.cs:392–400). Ghost Compare is visual verification, not dimensional proof or collision certification.

Honest empty and disabled states¶

See also¶

• Prepare for panel placement and the four working Process inputs.
• Preview for Color by, Ghost Compare, and layer inspection.
• Simulate for playback and findings triage.
• Slicer — interaction map for the current Enable route.
• Simulator — interaction map for current findings and overlay behavior.