Changelog

Versions follow the plugin (VersionName in DreamFX.uplugin). This page mirrors the repository's CHANGELOG.md.

Unreleased

Fixed

• 5.6 / 5.7: inputs revealed by a static switch are visible again (#1). Engines without the external edit API go through the Compat/ layer, and it stopped enumerating module inputs at the first UNiagaraStackFunctionInput. Module inputs are a hierarchy: an input a switch reveals is that switch's child, not its sibling — InitializeParticle's Lifetime hangs under LifetimeMode, UniformSpriteSize under SpriteSizeMode. So the probe saw 13 top-level inputs, writing a switch looked like it had no effect, and every argument it revealed was reported as a typo (DFX3003). Now it follows the engine's own two rules: descend into an input's children, stop at a Dynamic input. The write path uses the same resolver, so conditional inputs are addressable too. 5.8 and MoonEngine use the engine's own API and never took this path.
• 5.6 / 5.7: input visibility and editability now use the engine's three gates. GetIsHidden + VisibleCondition + EditCondition, matching GetStackInputTopology word for word. The previous GetShouldShowInStack / GetIsEnabled answer, on those engines, the "show modified only" filter and the host node's enabled state respectively, and both return true for everything — harmless while only top-level inputs were collected, and not harmless once conditional children are, because an unselected branch is a child that exists and is hidden. The decompiler skips inputs on !bVisible || !bEditable, and is the reader that gets fooled.
• A failed save no longer takes the editor down. Four UPackage::SavePackage sites (the adapter's write, module generation, the module library, the Phase 0 commandlet) used FSavePackageArgs' default Error = GError — and any message on GError is fatal, so "the file is in use by another program" (two editors' watchers rebuilding one .dfs, a read-only file, an antivirus holding it) killed the editor outright, and the DFX5030 path was never reached. SaveArgs.Error = GWarn puts the failure back into the build errors.
• DFX7102 no longer treats SpawnParticlesInGrid as rate-based spawning: like SpawnBurst it is a per-loop burst (X·Y·Z), bounded by the loop. The list keeps SpawnRate / SpawnPerUnit / SpawnPerFrame.

Documentation

• Calling a DI<X> input's functions from a .dfm body (Wind.SampleWind(Particles.Position, V, G)) needs the out arguments to be uninitialised locals: float G = 1.0; fails the CPU VM compile with out/inout parameters must be lvalues (DFX6006) — hlslcc constant-folds the initialised local into the argument list before it checks the out parameter. GPU accepts both; write the uninitialised form so one body compiles on both targets. See .dfm. The first external plugin data interface (DreamWind's UNiagaraDataInterfaceDreamWind) works end to end — reflection resolution through DI<DreamWind>, module input wiring, and User.Wind passed from a .dfs — with no DreamFX changes.

1.0.0 — 2026-08-13

The first release. Text sources (.dfs / .dfe / .dfm) → standard Niagara assets (UNiagaraSystem / UNiagaraEmitter / UNiagaraScript), full decompilation in the other direction, and a verification system built on the discipline that every claim carries a measurement.

Language and generation

• Full .dfs system definition: user parameters (including data interface parameters with their JSON configuration), the six system/emitter stacks, OnEvent handlers, named simulation stages (iteration source, bindings, ExecuteBehavior, NumIterations/Enabled as value or parameter), renderer property assignment and Bind, Settings (including bFixedTickDelta and system-level FixedBounds).
• Every value mode: literal / linked / enum / nested dynamic input / hlsl { } / curve { } (with Interp and Tangent=Auto|User|Break|None; a curve interface the readable form cannot express falls back to verbatim JSON — a convenience does not get to lose data).
• Static switches go through the override pin, the same path the engine's own stack UI uses, on both engines; the linked form resolves against the module's own DefaultBinding — equal is a no-op, unequal is refused, and there is no linking mechanism at the call site.
• .dfe reusable emitters copied in; .dfm module and dynamic input generation, working on the stock engine through the reflection backend.
• @version really selects; R7 provenance stamps (source hash, generator version, module version GUIDs).

Decompilation and mirrors

• Any UNiagaraSystem → .dfs, byte-for-byte idempotent; anything unexpressible is written into the file header as an explicit gap, never silently.
• The Decompiled/<original path> namespace: an export is first-class source that rebuilds on save and structurally cannot touch the original.
• Editor integration: menus, context menus, toolbars, the VSCode workspace, and Adopt (which refuses on any loss).

The four verification layers

• L1 mirror-diff line by line; L2 the mirror's compile; L3 runtime equivalence (fixed-step SimCache per-frame particle counts, with an A-vs-A self-comparison deciding decidability); and asset-level fact comparison asset-diff (a reflection walk that never touches the exporter, including the compiled fact family, with both sides force-compiled first). The 55-case corpus additionally compares "the asset built from a fixture" against "the asset rebuilt from its export" — symmetric loss has been visible since 2026-08-12.
• Four-step CI: lint → build → verify → corpus; gen-diagnostics.ps1 -Check guards against docs drift; 143 diagnostic codes, each with file, line and column.

Two engines

• MoonEngine (source 5.8.1) and stock installed 5.8.1 from one source tree with zero #if forks.
• The 1.0.0 round fixed four long-process defects on stock: the UObject count GC gate, ordering safety between collection and the live edit surface, a fallback for user parameters the engine drops when they have no default, and a fatal modification-during-iteration. Plus the host-project content plugin alignment requirement (see limits).

Verification snapshot (2026-08-13, commit 4e23c55)

Known issues

See limits.