FOpening

One tunnel mouth of a corridor: where the approach cutting folds to the portal, and where the face opens into a hole behind the portal's opening (Rail Earthworks Shoulders Skeleton, decisions 5 to 7).

Declaration

struct FOpening

Header: #include "Native/TerrainFeature.h"
Module: PublicDependencyModuleNames.Add("OrreryTerrainCore"); in your module’s Build.cs.
Stability: Stable: changes within a major version only add.

Description

Tier 1 data.

Millimetres throughout, in the corridor's own frame: along its station line, and lateral from it, positive on the left of the direction of travel (the HalfWidthLeft side). An opening sits at a boundary of one of the corridor's keep-out spans (IsValidOpening). The owner fills it from its portal plan and its portal kit's numbers; the terrain never reads a mesh.

The fold. Over Fold_mm outward of the facade, each side's batter reach is capped: the cap tapers from the feature's batter reach down to the head width's overhang beyond the formation band at the facade, and stays there between the facade and the span. The face is then HeadWidth_mm wide, and each capped side's step is reported as an EWallKind::PortalFold wall.
The hole. A cell is a hole when its plan centre lies within the outline's lateral extent plus one cell each side, from half a cell behind the facade to Depth_mm into the hill, and its four posts reach above the floor plus 0.25 m and below the outline's top at that lateral offset (MarkOpeningHoles). Holes are derived by the bake (FHeightTile::Holes), never saved.

Properties

Name	Type	Default	Meaning
`KeptOutStation`	`uint32_t`	`0`	The span's first station (entry) or its last (exit).
`bEntry`	`uint8_t`	`1`	1: the corridor enters the span here, so the cutting lies at lower stations; 0: it leaves the span.
`FacadeOffset_mm`	`int32_t`	`0`	Where the portal's facade stands: along the station line from KeptOutStation, outward (into the cutting).
`HeadWidth_mm`	`int32_t`	`0`	The headwall's outer width, centred on the station line: the face folds to it.
`Fold_mm`	`int32_t`	`0`	Fold length outward of the facade; 0 = no fold (the face keeps the cutting's whole section).
`Depth_mm`	`int32_t`	`0`	How far from the facade into the hill the hole may reach; 0 = no hole.
`OutlineUV_mm`	`std::vector<int32_t>`	—	The opening's outline, interleaved u0, v0, u1, v1, …: u lateral from the station line (left positive), v up from the formation on the station line. Counter-clockwise, open at the floor (the last point need not repeat the first). Empty = no hole; otherwise at least 2 points.