Orrery Terrain · OrreryTerrainEditor module · struct

FOrreryTerrainStampMesh

Editor only

One build of a stamp's preview: the post-aligned grid of StampPreviewPostGridWithin, its ground, the stamp's result there (EvaluateStampPreviewPosts: on every vertex the millimetres the stamp writes to that post), the mesh drawn from it, and the wire ghost from the same ground snapshot.

Declaration

struct FOrreryTerrainStampMesh

Header: #include "Tools/OrreryTerrainStampPreviewMesh.h"
Module: PublicDependencyModuleNames.Add("OrreryTerrainEditor"); in an editor module’s Build.cs: an editor module, not in packaged games.
Stability: Stable: changes within a major version only add.
Thread: Any thread once published.

Description

Immutable once built; the game thread and the render thread share it.

Vertex (I, J) lies at Origin_cm + (I, J) × Spacing_cm, its Z the result relative to Origin_cm.Z. Triangles (Indices) cover the cells where the stamp changes the ground; they are tinted cyan where it raises and orange where it cuts, lit through the result's normals, and fade out where the change is under a few decimetres, so unchanged ground is not covered. The cells with a vertex the stamp cuts (Cut) are listed again in CutIndices: the component draws them a second time through the ground (kCutMaterialPath), where the first pass is hidden. A wire-only build (no points to spare, or the mesh hidden after a click) has Width 0 and a Wire.

Note.

Any thread once published. Tier 3.

Functions

Properties

Name	Type	Default	Meaning
`Serial`	`uint64`	`0`	The request this answers (`FOrreryTerrainStampPreview` counts them from 1).
`Revision`	`uint64`	`0`	The ground snapshot's revision.
`Width`	`int32`	`0`	Vertices per row; 0 when the stamp has no grid.
`Height`	`int32`	`0`	Rows of vertices.
`Stride`	`int32`	`0`	Edit posts between vertices, a power of two (1 at the edit cell).
`Cell_mm`	`int64`	`0`	The terrain's edit cell.
`OriginPostX`	`int64`	`0`	Post index of vertex column 0.
`OriginPostY`	`int64`	`0`	Post index of vertex row 0.
`Spacing_cm`	`double`	`0.0`	World cm between vertices.
`Origin_cm`	`FVector`	`FVector::ZeroVector`	World position of vertex (0, 0) at the stamp's base height.
`Positions`	`TArray<FVector3f>`	—	Width × Height, row-major (J the row), cm relative to Origin_cm.
`Normals`	`TArray<FVector3f>`	—	The result's normals, per vertex.
`Gpu`	`TSharedPtr<const FOrreryTerrainStampMeshGpu>`	—	The tangent basis, packed on the worker; the render thread copies it whole.
`Colors`	`TArray<FColor>`	—	The tint, alpha the opacity; linear.
`Ground_mm`	`TArray<int32>`	—	The sampled ground per vertex (the stamp's base where there is none).
`Result_mm`	`TArray<int32>`	—	The stamp's result per vertex, the kernel's millimetres.
`Inside`	`TArray<uint8>`	—	1 where the stamp writes and the terrain has ground.
`Cut`	`TArray<uint8>`	—	1 where the vertex is inside and the result lies below the ground (MarkStampPreviewCuts).
`Indices`	`TArray<uint32>`	—	Triangle list over the cells the stamp changes.
`CutIndices`	`TArray<uint32>`	—	Triangle list over those of them with a vertex in Cut: drawn again through the ground.
`LocalBounds`	`FBox3f`	`FBox3f(ForceInit)`	Bounds of every vertex, relative to Origin_cm.
`InsideCount`	`int32`	`0`	Vertices inside.
`CutCount`	`int32`	`0`	Vertices in Cut.
`bLoaded`	`bool`	`false`	Every vertex's ground answered Exact.
`BuildMs`	`double`	`0.0`	Worker milliseconds: sampling, evaluation and the mesh, the wire included.
`Wire`	`TSharedPtr<const FOrreryTerrainStampWire>`	—	The wire ghost over the same snapshot; null when the stamp has no preview.