sprite-processing

name	sprite-processing
description	Use when processing, cropping, splitting, or cleaning up existing sprite images or sprite sheets. Triggers on "crop sprite", "remove background", "split sprite sheet", "make transparent", "process PNG".

Sprite Processing with PixelForge

Use process_sprite to clean up existing images into game-ready sprites.

Single Sprite Processing

Remove background and auto-crop:

process_sprite
  inputPath: "raw-enemy.png"
  outputPath: "public/assets/games/rpg/enemy.png"
  background: "chromakey"
  square: true

Prefer chromakey background — uses HSV-based green screen removal. Much cleaner than black/white.

Split Sprite Sheet

Split a horizontal sprite sheet into individual frames:

process_sprite
  inputPath: "animation-sheet.png"
  outputPath: "public/assets/games/rpg/hero"
  split: true
  names: ["idle", "walk-1", "walk-2", "attack"]
  background: "chromakey"
  square: true

Outputs: hero-idle.png, hero-walk-1.png, hero-walk-2.png, hero-attack.png

Two-Pass Processing

When sprite sheet has white background but individual sprites have black background:

# 1. Split sheet (removes white bg between sprites)
process_sprite
  inputPath: "sheet.png"
  outputPath: "public/assets/sprites/char"
  split: true
  names: ["head", "body", "legs"]
  background: "white"
  square: true

# 2. Remove black bg from each sprite
process_sprite
  inputPath: "public/assets/sprites/char-head.png"
  background: "black"
  threshold: 8
  skipCrop: true

Background Removal Methods

Background	Method	Best For
chromakey	HSV green screen	BEST — cleanest edges, no artifacts
black	Compositing equation	Dark-themed sprites
white	Compositing equation	Light-themed sprites
auto	Edge detection	Unknown backgrounds

Options Reference

Option	Default	Description
background	auto-detect	"chromakey", "black", "white", or "auto"
threshold	20	Color detection sensitivity (0-255)
square	false	Pad output to square dimensions
padding	2	Pixels of padding around content
split	false	Split sheet into individual sprites
names	0, 1, 2...	Names for split sprites
skipCrop	false	Keep original dimensions
skipTransparent	false	Don't remove background