TerrainNodeRecord

Remarks

The C# half of TerrainNode in Terrain.rvn, and the two agree by construction or not at all. The host packs these bytes and the shader reads them as a struct — the same bargain GpuCulling describes, and the same reason the duplication is not a smell to be refactored away.

⚠ Twenty-four bytes, and the last four are declared padding. Five floats is twenty in C# and twenty-four in std430, because a struct's alignment is its widest member's — the float2's eight — and its size rounds up to a multiple of it. A host writing a twenty-byte stride into an array the shader reads at twenty-four does not fail: it draws patch one out of the middle of patch zero, and every patch after that is further wrong. Adding a field changes both files or neither.

Fields and properties (6)

• public Vector2 Origin

  Where the patch's low corner is, in sample coordinates.

• public float Step

  How many samples one step of the grid patch spans.

• public float Morph

  How far the patch has morphed towards its parent's grid, 0…1.

• public float Level

  Which mip level of the atlas it reads.

• public float Padding0

  Declared rather than left to the compiler, so the record is twenty-four bytes on both sides.

• public static int SizeInBytes

  How many bytes one of these is.

Methods (2)

• public TerrainNodeRecord(Vector2 Origin, float Step, float Morph, float Level, float Padding0 = 0)

  One patch of terrain, as the vertex stage reads it.

• public static TerrainNodeRecord Of(in TerrainLodNode node, int gridQuads, int maxLevel = 0)

  The record for a node the quadtree selected.

Used by (3)

• TerrainGridPatchTestsVixen.Rendering.Terrain.Tests
• TerrainRendererVixen.Rendering.Terrain
• TerrainShaderParityTestsVixen.Rendering.Terrain.Tests