Refactoring

engine/debug.go

@@ -0,0 +1,15 @@
+package engine
+
+import (
+	"fmt"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
+)
+
+// TPSDisplay debugprints CurrentTPS in the top left.
+type TPSDisplay struct{}
+
+func (TPSDisplay) Draw(screen *ebiten.Image) {
+	ebitenutil.DebugPrint(screen, fmt.Sprintf("TPS: %0.2f", ebiten.CurrentTPS()))
+}

engine/game.go

@@ -0,0 +1,47 @@
+package engine
+
+import (
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+// Updater is a component that can update (called repeatedly).
+type Updater interface {
+	Update() error
+}
+
+// Drawer is a component that can draw itself (called repeatedly).
+type Drawer interface {
+	Draw(*ebiten.Image)
+}
+
+// Game implements the ebiten methods using a collection of components.
+type Game struct {
+	ScreenWidth, ScreenHeight int
+	Components                []interface{}
+}
+
+// Update calls Update on all Updater components.
+func (g *Game) Update() error {
+	for _, c := range g.Components {
+		if u, ok := c.(Updater); ok {
+			if err := u.Update(); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// Draw calls Draw on all Drawer components.
+func (g *Game) Draw(screen *ebiten.Image) {
+	for _, c := range g.Components {
+		if d, ok := c.(Drawer); ok {
+			d.Draw(screen)
+		}
+	}
+}
+
+// Layout returns the configured screen width/height.
+func (g *Game) Layout(outsideWidth, outsideHeight int) (w, h int) {
+	return g.ScreenWidth, g.ScreenHeight
+}

game.go

@@ -1,55 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"log"
-
-	"github.com/hajimehoshi/ebiten/v2"
-	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
-)
-
-const screenWidth, screenHeight = 320, 240
-
-type updater interface {
-	Update() error
-}
-
-type drawer interface {
-	Draw(*ebiten.Image)
-}
-
-type game struct {
-	components []interface{}
-}
-
-func (g *game) Update() error {
-	for _, c := range g.components {
-		if u, ok := c.(updater); ok {
-			if err := u.Update(); err != nil {
-				return err
-			}
-		}
-	}
-	return nil
-}
-
-func (g *game) Draw(screen *ebiten.Image) {
-	for _, c := range g.components {
-		if d, ok := c.(drawer); ok {
-			d.Draw(screen)
-		}
-	}
-	ebitenutil.DebugPrint(screen, fmt.Sprintf("TPS: %0.2f", ebiten.CurrentTPS()))
-}
-
-func (g *game) Layout(outsideWidth, outsideHeight int) (w, h int) {
-	return screenWidth, screenHeight
-}
-
-func main() {
-	ebiten.SetWindowSize(screenWidth*2, screenHeight*2)
-	ebiten.SetWindowTitle("ebiten")
-	if err := ebiten.RunGame(&game{}); err != nil {
-		log.Fatal(err)
-	}
-} 

main.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"log"
+
+	"drjosh.dev/gurgle/engine"
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+const screenWidth, screenHeight = 320, 240
+
+func main() {
+	ebiten.SetWindowSize(screenWidth*2, screenHeight*2)
+	ebiten.SetWindowTitle("ebiten")
+	if err := ebiten.RunGame(&engine.Game{
+		ScreenHeight: screenHeight,
+		ScreenWidth:  screenWidth,
+		Components: []interface{}{
+			engine.TPSDisplay{},
+		},
+	}); err != nil {
+		log.Fatal(err)
+	}
+}