// Find the width of the string
var ctx1 = onscreen_canvas.getContext('2d');
ctx1.font = font;
- var width = ctx1.measureText(midpoint_test_str).width;
+ var width = (ctx1.measureText(midpoint_test_str).width + 1) | 0;
// Construct a test canvas of appropriate size, initialise it to
// black, and draw the string on it in white