PopcornFX File Extensions

⚠️ This document is a work in progress. Information may be incomplete, inaccurate, or subject to change.

Effects

.pkfx (text)

Human-readable source format. Used in PK-Editor for authoring effects. Does not work in Reforged.

.pkfx (binary)

Baked binary version of an effect. Produced by PK-Editor or AssetBaker. Works in Reforged.

.pkb

Functionally identical to a baked .pkfx. Blizzard's preferred extension for baked effects in Reforged — the exact meaning of the abbreviation is unknown (PK Binary / Baked / Blizzard). Renaming the extension from .pkfx to .pkb is optional — the game can read both.

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Assets

.pkat

Texture atlas definition file. A simple text file containing a list of UV coordinates , used to describe the layout of a sprite sheet. Works in Reforged.

.pkmm

Baked 3D mesh data. Produced by the editor from source .fbx files. Referenced by effects that use mesh samplers. Works in Reforged.