When the canvas fabric is zoomed in, why does the polygon seem to extend beyond its borders?

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This may be due to an optical illusion called the Moiré effect, where patterns can appear distorted or seem to extend beyond their actual borders when viewed at certain scales or angles. It could also be a result of the way the canvas fabric is woven or textured, causing the edges of the polygon to appear blurry or distorted when zoomed in.