Pattern Card — Canonical Layer Stack

The 7-layer stack is fixed and semantically ordered. Reordering is a doctrine violation.

Visual

Order (bottom → top)

#	Layer	Blend	Opacity	When suppressed
1	Base imagery / neutral substrate	normal	100%	Never (foundational)
2	DEM hillshade	overlay	55–65%	Never on a degraded edge device with terrain context required
3	Contour or hachure slope overlay	multiply	100%	Performance suppression (after stipple)
4	Confidence stipple	screen	variable by provenance	First performance suppression on field tablet
5	Uncertainty wash	normal	variable by age tier	Last performance suppression — semantic loss is significant
6	Denied-zone crosshatch	normal	100%	Never (always required when geometry present)
7	Scan-line overlay	normal	4%	Whenever the surface is not a live ingest

Suppression order (field tablet, max 3 simultaneous textures)

1. Semantic suppressions (apply unconditionally before budget math)
   • Suppress scan_line_overlay when feed is not live (non_live_cached_feed)
2. Performance suppressions (apply in priority order until under budget)
   1. Drop confidence_stipple
   2. Drop contour_hachure
   3. Drop uncertainty_wash (last resort — semantic loss is significant)
3. Emit REDUCED_SEMANTIC_FIDELITY warning whenever any performance suppression fires.

Why this order

The stack reads bottom-to-top in trust hierarchy: terrain truth at the bottom, operational state in the middle, denial geometry above all terrain interpretation, live signal indication on top. Inverting any pair changes what the operator sees first — and therefore changes what they trust first.

Tokens reference

Layer compositing parameters live alongside the doctrine in SKILL.md. Per-layer fills/strokes live in tokens.json.