# Setting up a coordinate system and canvas size for subsequent drawing

I'd like to create a blank Graphics object of a certain size with a certain coordinate system (PlotRange) and subsequently draw stuff to it with respect to the already-established coordinate system. However, I'm finding out that subsequent objects ignore the existing coordinate system. FOr instance:

g = Graphics[PlotRange -> {{0, 4.6}, {0, 2}}, ImageSize -> {460, 200},
Background -> LightGray];
g = Show[g, Graphics[{Thickness[0.01], Line[{{0, 0}, {1, 1}}]}]]


I would expect the line from the second line to start at the bottom left. Instead, the entire Graphics object is centered.

This works. Just add {} to the first g
g=Graphics[{},PlotRange->{{0,4.6},{0,2}},ImageSize->{460,200},

• @Wynne it was just a guess, that it the first g needed "something" in there to set. Even if that something was just the empty list. Show also takes options from the first argument. So I just tried {} to make it happy and it worked. This might be documented somewhere, I have no idea. – Nasser Feb 18 '18 at 3:59