DistanceFieldInstance

Remarks

Position, rotation and one scale — not a matrix, and that is the point. A distance field survives being moved and turned, and it survives being scaled by one number: rotate a distance and it is the same distance, scale everything by s and every distance scales by s too. It does not survive a non-uniform scale. Squash a sphere's field along one axis and what comes out is not the ellipsoid's distance function — it over-reports along the squashed axis and under-reports across it, and a tracer reading it steps straight through the surface. Taking a Matrix4x4 here would accept that silently, so the type refuses to be able to express it.

A mesh that genuinely needs a non-uniform scale needs its own bake at that scale. That is what every engine that ships this does, and it is why a field is a property of a mesh asset rather than of a renderer.

Fields and properties (5)

• public MeshDistanceField Field

  The baked field, in its own space.

• public Vector3 Position

  Where its origin sits in the world.

• public Quaternion Rotation

  How it is turned. Must be normalised.

• public float Scale

  How much bigger it is than it was baked. Must be positive.

• public BoundingBox WorldBounds

  The world-space box the field covers, which is what a query rejects against.

Methods (4)

• public DistanceFieldInstance(MeshDistanceField Field, Vector3 Position, Quaternion Rotation, float Scale)

  One baked field, placed in a world.

• public static DistanceFieldInstance At(MeshDistanceField field, Vector3 position)

  Places a field without turning or resizing it.

• public float Sample(Vector3 world)

  The signed distance at a world-space point.

• public void Validate()

  Throws if the instance cannot be sampled.

Used by (12)

• ArenaThirdPersonShooter
• ArenaIlluminationThirdPersonShooter
• DistanceFieldInstanceTestsVixen.Rendering.DistanceFields.Tests
• DistanceFieldTracerTestsVixen.Rendering.DistanceFields.Tests
• GlobalDistanceFieldVixen.Rendering.DistanceFields
• GlobalDistanceFieldRendererVixen.Rendering
• GlobalDistanceFieldRendererTestsVixen.Rendering.Tests
• GlobalDistanceFieldTestsVixen.Rendering.DistanceFields.Tests
• ReflectionTraceDeviceTestsVixen.Graphics.Golden.Tests
• RenderedSceneTestsVixen.Rendering.DistanceFields.Tests
• ScrollTestsVixen.Rendering.DistanceFields.Tests
• SurfaceCacheRadiosityDeviceTestsVixen.Graphics.Golden.Tests