HTML Guide

Bad value “X1,Y1,X2,Y2” for attribute “coords” on element “area”: A circle must have three comma-separated integers. The first integer must be less than the third. A polyline must have at least six comma-separated integers.

The coordinates specified for an <area> element using the coords attribute are not in a valid format.

For a rectangle (shape="rect"), the format X1,Y1,X2,Y2 is expected, where the top-left corner is specified by X1, Y1 and the bottom-right corner is specified by X2, Y2, therefore X1 must be lower than X2, and Y1 must be lower than Y2 because the coordinates 0, 0 start at the top-left.
For a polygon (shape="poly"), the format X1,Y1,X2,Y2,...,Xn,Yn is expected to contain a list of coordinate pairs (at least 3, for a triangle).
For a circle (shape="circle"), the format X,Y,R is expected where X, Y represents the coordinates of the center of the circle (from the top-left corner), and R is the radius.

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