package game import ( "github.com/hajimehoshi/go.ebiten/graphics" "github.com/hajimehoshi/go.ebiten/graphics/matrix" "image" "image/color" _ "image/png" "os" ) type RotatingImage struct { ebitenTexture graphics.Texture x int } func NewRotatingImage() *RotatingImage { return &RotatingImage{} } func (game *RotatingImage) Init(tf graphics.TextureFactory) { file, err := os.Open("ebiten.png") if err != nil { panic(err) } defer file.Close() img, _, err := image.Decode(file) if err != nil { panic(err) } game.ebitenTexture = tf.NewTextureFromImage(img) } func (game *RotatingImage) Update() { game.x++ } func (game *RotatingImage) Draw(g graphics.GraphicsContext, offscreen graphics.Texture) { g.Fill(&color.RGBA{R: 128, G: 128, B: 255, A: 255}) geometryMatrix := matrix.IdentityGeometry() tx, ty := float64(game.ebitenTexture.Width), float64(game.ebitenTexture.Height) geometryMatrix.Translate(-tx/2, -ty/2) geometryMatrix.Rotate(float64(game.x) / 60) geometryMatrix.Translate(tx/2, ty/2) centerX, centerY := float64(offscreen.Width) / 2, float64(offscreen.Height) / 2 geometryMatrix.Translate(centerX - tx/2, centerY - ty/2) g.DrawTexture(game.ebitenTexture.ID, 0, 0, int(tx), int(ty), geometryMatrix, matrix.IdentityColor()) }