Alpine and Canyon habitat pass — 16 September 2026

The successful native images in Docs/QA/20260916-131525-graphics-all-levels show two composition problems: Canyon has very sparse, repeated isolated rocks on a nearly empty plateau; Alpine meadow margins lack the mixed understory that should connect grass, woods and rock. This pass adds bounded visual scenery to those specific areas. The separate Canyon distant terrain relief remains unchanged.

AlpineCanyonDressing.BuildAlpine adds irregular clusters of native photographed fern fronds and dry tussocks, weathered limestone stones, occasional small native broadleaf shrubs, and fallen edge timber. Woodland-cover density and footprint slope limit the vegetation to plausible edge habitat. Alpine winter gets only the rock component. The maximum static shrubs are 75 on High and 25 on Low; fallen timber is capped at 22/8. Existing tree positions and crowns remain unchanged.

BuildCanyon adds mixed small rubble clusters, low stratified rock shelves and occasional 15–45 m remnants on the inland side of the road. Broad gaps preserve the view into the main canyon. Sparse cacti and photographed dry grass supply human-scale foreground detail. At most two small weathered timber trail shelters with benches and stone foundations occupy supported plateau sites. Existing photographic rock, grass, bark and bridge-timber materials are reused; the cactus is a small matte procedural source, not a newly imported asset. The Canyon hook is inside CanyonLandscape.BuildScenery; Alpine is integrated from the normal scenery build.

Each stage owns only a few generated prototype meshes. DressingInstances renders them through native Graphics.RenderMeshInstanced, with per-camera frustum and distance culling and explicit visible triangle caps. High caps are 76,000 for Alpine instances and 115,000 for Canyon instances; Low caps are 26,000/42,000. Fern and tussock radii are 140/155 m on High; small Canyon plants are 230–380 m; larger outcrops remain visible to 1,200–2,200 m. The last 18% of each radius smoothly shrinks instances into their grounded origin. Source shrubs and the few shelters/logs are spatially combined separately. No per-plant GameObjects or new texture allocations are added.

All chapter roads are included in a conservative clearance index. The active route also receives an exact nearest-road check. Footprints are tested at centre plus eight perimeter points against the actual rendered terrain triangle grid, with the existing apron included only within its range. Rock feet use the lowest footprint sample to embed naturally; plants use their own contact point. Canyon sites additionally reject bridge stations and terrain below the upper plateau. No road, grade, bridge, gorge, terrain height, checkpoint or collider is changed by this dressing pass.

All runtime source compiled with warnings treated as errors using the installed Unity Mono compiler, without launching Unity or a player. A small follow-up improved rock-foot burial and matching the rendered ground outside the apron. Root owns the consolidated build and image review. Until those images are examined, the density/composition and native material appearance are unverified; this pass is not a photorealism acceptance.

Coastal and forest extension

CoastalForestDressing.Build(track) is the separate guarded integration entry for Jungle, China and Mediterranean. It reuses the same ground seating, road clearance and DressingInstances implementation. Jungle/China receive small photographed bent fern fronds, tussocks and weathered limestone fragments. Ferns stay approximately 0.3–0.7 m tall and use the existing atlas rather than large placeholder leaves. Chinese ridge wall sites and all active bridge sections are excluded.

The extension caps generated visible instance triangles at 45,000 on High and 16,000 on Low. Whole-stage counts are also limited to 260/120 rock fragments and 1,400/550 plants. The Mediterranean chapter gets at most 15/8 native CoastalPalm/CoastalPalmBent sources using their existing three authored LODs, plus at most two low stone viewpoints and benches where the complete footprint has at most 0.45 m relief. Palms and walls have no colliders. Stone footings are embedded into the lowest footprint sample. These sparse structures use existing stone and bridge-timber photographic materials.

The final source-only all-runtime compilation, including this extension and the earlier contact fixes, passed at 14:20 Vienna. Only the viewpoint seating threshold was subsequently tightened from 0.70 m to 0.45 m with lowest-footprint burial. No Unity/player or additional physics test loop was launched. Root supplies both integration hooks and the native build/image validation.