Four map projections—Lagrange, azimuthal equal-area, orthographic, and azimuthal equidistant—are arranged in a 2x2 grid to form a single composite projection. The d3.geoPath renderer draws world landmasses from TopoJSON, a graticule, and the sphere outline, with each projection clipped to its quadrant. A custom `projection.invert` method tests each quadrant to locate mouse positions, and the red inverted point follows the cursor. Continuous rotation of all four projections via d3.timer produces an animated display.