draw a line smaller than "1"

I draw rect twice on the canvas,and the border would be “bigger” than draw only once. how can avoid this?
and How can I draw a small line with a smaller width?

what you are probably seeing is the result of AntiAlias… .where it takes what is already there, combines it with what you just drew.
Turn it off and see what happens.

And no… PenWidth is an Integer, so the only thing less than 1 is 0

the pendwidth of 1 is “big” in my screen…

g.scaleX and g.scaleY can help here.