VfxSystem

Remarks

The graph is the effect and this is the effect happening. A graph is shared between every instance of it — the same array of operations, read and never written — and everything that differs between two campfires is here: how far through they are, what their seeds are, and the particles themselves.

Two instances with the same seed and the same steps are identical. Not similar: identical, particle for particle, because nothing in the simulation reads a clock, a thread identifier, or anything else the caller did not hand it. That is what makes an effect reproducible in a replay and testable against a golden image, and it is the reason VfxRandom is stateless.

Time is accumulated, not integrated. A rate spawner keeps its fractional debt across steps, so 2.5 particles a second at sixty hertz emits five particles every two seconds rather than none at all — which is what dropping the fraction would do, and what makes a low-rate emitter mysteriously silent.

Fields and properties (16)

• public VfxCompiledGraph Graph

  The graph being run.

• public uint Seed

  The instance's seed.

• public Vector3 Origin

  Where the emitter is. Added to every position an initializer writes.

• public ParticleBuffer Particles

  Its particles.

• public float Time

  How long it has been running, in seconds.

• public int Count

  How many particles are alive.

• public bool Emitting

  Whether the spawners are running. Particles already alive keep going either way.

• public int LastSpawned

  How many particles the last Step spawned.

• public int FirstSpawned

  Where the particles the last Step spawned begin.

• public bool RecordDeaths

  Whether to remember where particles died, for a sub-emitter to use.

• public int LastDied

  How many particles died in the last Step.

• public ReadOnlySpan<Vector3> Deaths

  Where they were when they died, when RecordDeaths is on.

• public JobScheduler? Scheduler

  Where the sweeps run, or null to run them on the calling thread.

• public int ParallelThreshold

  How many particles it takes before Scheduler is used at all.

• public bool LastStepWasParallel

  Whether the last Step ran its sweeps across threads.

• public int LastRefused

  How many the last Step could not spawn because the buffer was full.

Methods (4)

• public VfxSystem(VfxCompiledGraph graph, uint seed = 1)

  Starts an instance of a graph.

• public void Step(float deltaTime)

  Advances the effect.

• public void Reset()

  Kills every particle and puts the clock back to zero.

• public void Dispose()

  Frees the particle storage.

Used by (21)

• SweepBenchmarksVixen.Benchmarks.Vfx
• ParticleLightTestsVixen.Rendering.Tests
• ParticleLightsVixen.Rendering
• ParticleRenderFeatureVixen.Rendering
• ParticleRenderFeatureTestsVixen.Rendering.Tests
• ParticleSpriteDeviceTestsVixen.Graphics.Golden.Tests
• VfxCustomAttributeTestsVixen.Vfx.Tests
• VfxExtractionSystemVixen.Rendering
• VfxExtractionTestsVixen.Rendering.Tests
• VfxForceTestsVixen.Vfx.Tests
• VfxGeometryBuilderVixen.Vfx
• VfxGeometryTestsVixen.Vfx.Tests
• VfxParallelTestsVixen.Vfx.Tests
• VfxRibbonTestsVixen.Vfx.Tests
• VfxSubEmitterVixen.Vfx
• VfxSubEmitterTestsVixen.Vfx.Tests
• VfxSystemTestsVixen.Vfx.Tests
• AuthoringTestsVixen.Editor.AssetEditors.Tests
• VfxDocumentVixen.Editor.AssetEditors
• VfxGraphCompilerTestsVixen.Editor.VfxGraph.Tests
• VfxPreviewViewVixen.Editor.AssetEditors