It still isn't perfect (e.g. it doesn't join), but it's getting closer.
Also fix the bug where RotateCW and RotateCCW was mixed up, since the
Y-axis grows down in a computer graphics co-ordinate system, not up as
in classical mathematics.
R=r, rsc, rog
CC=golang-dev
http://codereview.appspot.com/1736043
The stroking algorithm is a placeholder. A proper one will land in a
future change once the API is agreed upon.
R=r, rsc
CC=golang-dev, rog
http://codereview.appspot.com/1708045
magic zero value to indicate end of painting.
This means that Painter implementations can assume thant the Spans' Y
values are monotonic.
R=rsc
CC=golang-dev, rog
http://codereview.appspot.com/1261043
draw text onto an image.
This is a simple API that doesn't handle line breaking, ligatures,
right-to-left or vertical scripts, and other fancy features.
R=r, rsc
CC=golang-dev
http://codereview.appspot.com/1121045
