gg/examples/invert-mask.go

package main

import "github.com/fogleman/gg"

func main() {
	dc := gg.NewContext(1024, 1024)
	dc.DrawCircle(512, 512, 384)
	dc.Clip()
	dc.InvertMask()
	dc.DrawRectangle(0, 0, 1024, 1024)
	dc.SetRGB(0, 0, 0)
	dc.Fill()
	dc.SavePNG("out.png")
}