Add 0002-getting-started-with-ebitengine

0002-getting-started-with-ebitengine/game.go

@@ -1,22 +1,89 @@
 package main
 
-import "github.com/hajimehoshi/ebiten/v2"
+import (
+	"image"
+	"image/color"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/inpututil"
+)
+
+const (
+	screenW, screenH = 256, 144
+	playerW, playerH = 22, 42
+	groundH          = 42
+)
+
+var (
+	backgroundColor = color.RGBA{255, 255, 255, 255}
+	groundColor     = color.RGBA{71, 39, 2, 255}
+	playerColor     = color.RGBA{6, 154, 46, 255}
+)
 
 type game struct {
+	// Player image.
+	playerImg *ebiten.Image
+
+	// Player attributes.
+	positionX, positionY float64
+
+	// Game attributes.
+	fullscreen  bool
+	initialized bool
 }
 
-func (g game) Update() error {
+// initialize sets up the initial state of the game.
+func (g *game) initialize() {
+	if g.initialized {
+		return
+	}
+
+	// Initialize player image.
+	g.playerImg = ebiten.NewImage(playerW, playerH)
+	g.playerImg.Fill(playerColor)
+
+	// Initialize player attributes.
+	g.positionX = screenW/2 - playerW/2
+	g.positionY = screenH - groundH
+
+	// Initialize game attributes.
+	g.fullscreen = true
+	g.initialized = true
+}
+
+// Layout is called each frame with the current size of the window.
+func (g *game) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
+	// Use fixed screen size.
+	return screenW, screenH
+}
+
+// Update is where we update the game state.
+func (g *game) Update() error {
+	// Handle initialization.
+	if !g.initialized {
+		g.initialize()
+	}
+
+	// Handle fullscreen.
+	if inpututil.IsKeyJustPressed(ebiten.KeyEnter) && ebiten.IsKeyPressed(ebiten.KeyAlt) {
+		g.fullscreen = !g.fullscreen
+		ebiten.SetFullscreen(g.fullscreen)
+	}
+
 	return nil
 }
 
-func (g game) Draw(screen *ebiten.Image) {
+// Draw is where we draw the game state.
+func (g *game) Draw(screen *ebiten.Image) {
+	// Draw background.
+	screen.Fill(backgroundColor)
 
-}
+	// Draw ground.
+	groundRect := image.Rect(0, screenH-groundH, screenW, screenH)
+	screen.SubImage(groundRect).(*ebiten.Image).Fill(groundColor)
 
-func (g game) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
-	return outsideWidth, outsideHeight // Set viewport size to new window size.
-}
-
-func newGame() *game {
-	return &game{}
+	// Draw player.
+	op := &ebiten.DrawImageOptions{}
+	op.GeoM.Translate(g.positionX, g.positionY-playerH)
+	screen.DrawImage(g.playerImg, op)
 }

0002-getting-started-with-ebitengine/main.go

@@ -9,11 +9,12 @@ import (
 func main() {
 	ebiten.SetWindowTitle("TT0002: Getting Started with Ebitengine")
 	ebiten.SetWindowResizingMode(ebiten.WindowResizingModeEnabled)
-	ebiten.SetWindowSize(800, 600)
+	ebiten.SetWindowSize(screenW, screenH)
+	ebiten.SetFullscreen(true)
 	ebiten.SetVsyncEnabled(true)
 	ebiten.SetTPS(60)
 
-	err := ebiten.RunGame(newGame())
+	err := ebiten.RunGame(&game{})
 	if err != nil {
 		log.Fatal(err)
 	}