Draws a line between the coordinates (x1,y1) and (x2,y2). The line is drawn below and to the left of the logical coordinates. @param x1 the first point's x coordinate @param y1 the first point's y coordinate @param x2 the second point's x coordinate @param y2 the second point's y coordinate
(int x1, int y1, int x2, int y2)
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