Chip-Firing Visualizer

Modes

Fire mode	Box-drag to select multiple vertices; selection persists until fired
Pan mode	Drag canvas to pan; drag vertices to reposition
Build mode	Double-click canvas to add vertex; Shift-drag vertex→vertex to add edge; right-click vertex or edge to delete

Chip-firing

Double-click vertex	Fire that vertex (send one chip along each edge)
Shift + double-click vertex	Borrow at that vertex (pull one chip from each neighbor)
Select + Enter / Fire Selected	Fire all selected vertices simultaneously
Shift + Enter / Borrow Selected	Borrow at all selected vertices simultaneously
Right-click vertex	Context menu: add / remove / set chips (Pan & Fire modes)
Zero Divisor	Set all vertices to 0 chips
Canonical Divisor	Set each vertex to deg(v) − 2
Undo	Undo last chip or graph change (all operations supported)

Dhar's burning algorithm

Select one vertex + B / Burn	Run Dhar's algorithm from that vertex (q); animates burn steps
Clear Burn	Remove burn highlighting

JSON import / export

Import JSON	Load a graph from Graph / Finite State Machine Designer JSON format
Export JSON	Export current graph to the same format

JSON format compatible with Graph / Finite State Machine Designer (GFSM Designer).