package main import ( "fmt" "log" "os" "bufio" "math" "image" "time" "image/png" "exp/draw" "draw2d.googlecode.com/hg/draw2d" ) func saveToPngFile(filePath string, m image.Image) { f, err := os.Open(filePath, os.O_CREAT|os.O_WRONLY, 0600) if err != nil { log.Println(err) return } defer f.Close() b := bufio.NewWriter(f) err = png.Encode(b, m) if err != nil { log.Println(err) return } err = b.Flush() if err != nil { log.Println(err) return } fmt.Printf("Wrote %s OK.\n", filePath) } func loadFromPngFile(filePath string) image.Image { f, err := os.Open(filePath, 0, 0) if f == nil { log.Printf("can't open file; err=%s\n", err.String()) return nil } defer f.Close() b := bufio.NewReader(f) i, err := png.Decode(b) if err != nil { log.Println(err) os.Exit(1) } fmt.Printf("Read %s OK.\n", filePath) return i } func main() { source := loadFromPngFile("../resource/image/TestAndroid.png") dest := image.NewRGBA(1024, 768) width, height := float64(source.Bounds().Dx()), float64(source.Bounds().Dy()) tr := draw2d.NewIdentityMatrix() tr.Translate(width/2, height/2) tr.Rotate(30 * math.Pi / 180) tr.Translate(-width/2, -height/2) tr.Translate(75, 25) lastTime := time.Nanoseconds() draw2d.DrawImage(source, dest, tr, draw.Over, draw2d.BilinearFilter) dt := time.Nanoseconds() - lastTime fmt.Printf("Draw image: %f ms\n", float64(dt)*1e-6) saveToPngFile("../resource/result/TestDrawImage.png", dest) }