Go Graphics
Go Graphics - 2D rendering in Go with a simple API
...They're mostly for testing the code, but they're good for learning, too. It is often desired to center an image at a point. Use DrawImageAnchored with ax and ay set to 0.5 to do this. Use 0 to left or top align. Use 1 to right or bottom align. DrawStringAnchored does the same for text, so you don't need to call MeasureString yourself. gg supports linear, radial and conic gradients and surface patterns. You can also implement your own patterns. It is often desired to rotate or scale about a point that is not the origin. The functions RotateAbout, ScaleAbout, ShearAbout are provided as a convenience.