<!DOCTYPE html> <!-- Copyright 2013 The Ebiten Authors Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <link rel="shortcut icon" href="../favicon.png" type="image/png" > <link rel="icon" href="../favicon.png" type="image/png" > <title>Ebiten example - rotate</title> <style> body { font-family: sans-serif; } iframe { border-color: #999; border-style: solid; border-width: 1px; overflow: hidden; } pre { background: #eee; padding: 1em; } </style> <nav><a href="..">Ebiten</a></nav> <h1>Ebiten example - rotate</h1> <iframe src="rotate.content.html" width="640" height="480"></iframe> <pre><code>package main import ( _ "image/jpeg" "log" "math" "github.com/hajimehoshi/ebiten" "github.com/hajimehoshi/ebiten/ebitenutil" ) const ( screenWidth = 320 screenHeight = 240 ) var ( count int gophersImage *ebiten.Image ) func update(screen *ebiten.Image) error { count++ w, h := gophersImage.Size() op := &ebiten.DrawImageOptions{} op.GeoM.Translate(-float64(w)/2, -float64(h)/2) op.GeoM.Rotate(float64(count%360) * 2 * math.Pi / 360) op.GeoM.Translate(screenWidth/2, screenHeight/2) if err := screen.DrawImage(gophersImage, op); err != nil { return err } return nil } func main() { var err error gophersImage, _, err = ebitenutil.NewImageFromFile("_resources/images/gophers.jpg", ebiten.FilterNearest) if err != nil { log.Fatal(err) } if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Rotate (Ebiten Demo)"); err != nil { log.Fatal(err) } } </code></pre> <footer>© 2013 Hajime Hoshi</footer>