An interactive archaeological floor-plan drawing tool overlays a standardized grid with corner balks onto an SVG canvas, using D3 v7 to render grid lines and border rectangles. Users draw walls and place artifact markers through mouse events that call `d3.pointer` and custom grid-snapping logic. The interface includes tool selection buttons for walls, objects, erasing, and clearing, with all elements snapped to the predefined 40-pixel grid increment.