What is wha-spell-simulator?

This is a fan-made browser application inspired by the manga Witch Hat Atelier, a series in which spell casting works through drawing geometric diagrams. The app lets a user draw a spell diagram on a canvas and then runs it through a parser to produce structured output and animated visual effects. Drawing on the canvas produces a freehand diagram. The app detects one enclosing ring and classifies the spell as either prepared or active based on its state. It recognizes a dictionary of primary sigils corresponding to five elements: fire, water, wind, earth, and light. It also recognizes modifier signs that affect direction, levitation, convergence, force, spread, focus, range, duration, and stability. Once the diagram is parsed, the app produces three kinds of output for inspection: a GlyphAST representing the recognized shapes, a SpellIR representing the compiled spell behavior, and animated canvas effects that visualize the element associated with the spell. A Dictionary panel shows sample spell layouts as drawing references. Parser diagnostics appear when a drawing has problems. The project includes a set of developer reference tools accessible from the app: a stroke template maker and viewer, a sigil and sign detector lab, and a spell effect lab for tuning visual animations. The full codebase is JavaScript, runs on Vite, and includes a Node test suite. The README is candid about limitations. The app supports one spell ring and one primary sigil at a time, and recognition works best with clean, deliberate drawings. The sigil dictionary covers a small fan-made subset rather than any canonical rule set, and the visual effects are interpretive rather than faithful reproductions of the manga's artwork. The project is not affiliated with the official creators.