After placing a few curves as stems, leaf starting points are guided along the gradients of a two-dimensional distance volume to draw the backbones of the leaves.
Curves and volume are mutually affecting each other inside a single solver: The drawn curves are being painted into the volume while the curve is guided by the volume's gradient.
Next the distances towards these curves are remapped into leaf-like shapes building voronoi cells that are modified by a function curve and a sine wave.
