Different Shape Reproduction with D3 demonstrates how SVG masks can be combined to create complex visual compositions. The visualization layers horizontal and vertical striped rectangles, each masked by a distinct pattern of D3 symbols. Using d3.select, d3.range, d3.symbol, and d3.symbols, the code generates 100 repeating bars in both directions, with a mask revealing symbol shapes in inverted and non-inverted forms. The React-framework example renders entirely in SVG, with masks applied via the renderMask function to produce the final overlapping effect.