Write x coordinate. Math.round(nr*10)/10

Canvas 400x200 pixel

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Esempio-spiega

Math.round(12.34) == 12
Math.round(12.34 * 10) / 10 == 12.3

dim:
12.34 * 10 == 123.4
Math.round(123.4) == 123
123/10 == 12.3