rename presenter to constructor (memoriem of Last Ninja)

constructor/engine.go

@@ -0,0 +1,33 @@
+package constructor
+
+import (
+	"game/domain"
+	"image/color"
+
+	"github.com/hajimehoshi/ebiten"
+)
+
+const (
+	screenWidth  = 320
+	screenHeight = 240
+)
+
+type GameEngine struct {
+	Context  domain.Context
+	Keyboard Keyboard
+}
+
+func (g *GameEngine) Update(screen *ebiten.Image) error {
+	g.Keyboard.Watch()
+	return nil
+}
+
+func (g *GameEngine) Draw(screen *ebiten.Image) {
+	if g.Keyboard.UpPressed() {
+		screen.Fill(color.White)
+	}
+}
+
+func (g *GameEngine) Layout(outsideWidth, outsideHeight int) (int, int) {
+	return screenWidth, screenHeight
+}