程序生成的鱼类图谱

Define a fish body as two spline curves (top and bottom profile) driven by random parameters for length, depth and taper. Generate fins as fans of polylines with rays, place an eye and mouth at proportional positions, then tile scale arcs along a curvilinear grid inside the body. Shade by adding hatch lines whose density depends on distance from the belly. Implement polygon clipping so nearer parts hide strokes behind them, and export everything as plain polylines in SVG.