<!DOCTYPE html> <script src="../scripts/force-https.js"></script> <link rel="shortcut icon" href="../favicon.png" type="image/png" > <link rel="icon" href="../favicon.png" type="image/png" > <title>Ebiten example - paint</title> <link rel="stylesheet" href="../stylesheets/bootstrap.min.css"> <link rel="stylesheet" href="../stylesheets/highlight-github.css"> <link rel="stylesheet" href="../stylesheets/ebiten.css"> <script src="../scripts/googleanalytics.js"></script> <header class="navbar"><div class="container"> <div class="navbar-header"> <a class="navbar-brand" href="..">Ebiten</a> </div> <nav class="collapse navbar-collapse"> <ul class="nav navbar-nav navbar-right"> <li><a href="https://github.com/hajimehoshi/ebiten">GitHub</a></li> <li><a href="https://godoc.org/github.com/hajimehoshi/ebiten">GoDoc</a></li> <li><a href="https://github.com/hajimehoshi/ebiten/wiki">Wiki</a> </ul> </nav> </header> <main><div class="container"> <h2>Ebiten example - paint</h2> <iframe src="paint.content.html" width="640" height="480"></iframe> <pre><code class="language-go">// +build example package main import ( "fmt" "image" "image/color" "log" "math" "github.com/hajimehoshi/ebiten" "github.com/hajimehoshi/ebiten/ebitenutil" ) const ( screenWidth = 320 screenHeight = 240 ) var ( count int brushImage *ebiten.Image canvasImage *ebiten.Image ) func paint(screen *ebiten.Image, x, y int) error { op := &ebiten.DrawImageOptions{} op.GeoM.Translate(float64(x), float64(y)) op.ColorM.Scale(1.0, 0.50, 0.125, 1.0) theta := 2.0 * math.Pi * float64(count%60) / ebiten.FPS op.ColorM.RotateHue(theta) if err := canvasImage.DrawImage(brushImage, op); err != nil { return err } return nil } func update(screen *ebiten.Image) error { drawn := false mx, my := ebiten.CursorPosition() if ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) { if err := paint(screen, mx, my); err != nil { return err } drawn = true } for _, t := range ebiten.Touches() { x, y := t.Position() if err := paint(screen, x, y); err != nil { return err } drawn = true } if drawn { count++ } if err := screen.DrawImage(canvasImage, nil); err != nil { return err } msg := fmt.Sprintf("(%d, %d)", mx, my) for _, t := range ebiten.Touches() { x, y := t.Position() msg += fmt.Sprintf("\n(%d, %d) touch %d", x, y, t.ID()) } if err := ebitenutil.DebugPrint(screen, msg); err != nil { return err } return nil } func main() { var err error const a0, a1, a2 = 0x40, 0xc0, 0xff pixels := []uint8{ a0, a1, a1, a0, a1, a2, a2, a1, a1, a2, a2, a1, a0, a1, a1, a0, } brushImage, err = ebiten.NewImageFromImage(&image.Alpha{ Pix: pixels, Stride: 4, Rect: image.Rect(0, 0, 4, 4), }, ebiten.FilterNearest) if err != nil { log.Fatal(err) } canvasImage, err = ebiten.NewImage(screenWidth, screenHeight, ebiten.FilterNearest) if err != nil { log.Fatal(err) } if err := canvasImage.Fill(color.White); err != nil { log.Fatal(err) } if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Paint (Ebiten Demo)"); err != nil { log.Fatal(err) } } </code></pre> </div></main> <footer><div class="container"> <p>© 2013 Hajime Hoshi</p> <p>Code is licensed under <a href="https://github.com/hajimehoshi/ebiten/blob/master/LICENSE">the Apache License 2.0</a>.</p> <p>The content of this page is licensed under <a href="https://creativecommons.org/licenses/by/4.0/">the Creative Commons Attribution 4.0 License</a>.</p> </div></footer> <script src="../scripts/highlight.pack.js"></script> <script>hljs.initHighlightingOnLoad();</script>