The mathematics of weave. Draw all the vertical sections first, complete. Then draw the horizontal sections on top, in pieces. We must calculate the horizontal and vertical coordinates of each piece, plus the width and height.
The pieces are rectangles, but we use gradients to emphasize the 3D structure. You can remove the gradient or accentuate it further.
Do the colors change where they overlap? The blue pieces seem darker where they overlap the green. The green pieces seem more saturated where they overlap the blue. This effect seems related to the distance between the threads, but is unrelated to the gradient. Why do we see this?
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