Asset pipeline: from art to engine-ready files

The fal-assets skill makes pictures. This skill makes files the game accepts: the right size, frame layout, orientation, alpha, palette and format. All commands are um sprite ... and um render3d ...; each has --help with examples.

1. Learn the target format from the game itself

Before converting anything, open two or three of the game's own assets and write down in MODLOG.md:

• Dimensions: frame size, frames per sheet, and the layout (vertical strip / grid / one file per frame).
• Orientation: which way the art faces (Terraria: items point right, NPCs face left, the engine flips them), and where the pivot or hotspot sits (AoE2: the unit's ground point at the canvas centre).
• Alpha: hard 1-bit edges (BC1 punch-through, pixel art) or soft.
• Style: palette size and outline (dark 1-2 px outline in most pixel-art games).
• Format: PNG, DDS BC1/BC3/BC7, XNB, SLD, atlas + JSON...

The draw code is the final authority. In Terraria, NPC frame height = texture height / Main.npcFrameCount, so any consistent frame size works.