FEATURE: Mandarin rain!; First release version

src/game/audio.go

@@ -0,0 +1,46 @@
+package game
+
+import "strings"
+
+// Plays sound and rewinds the player
+func (g *Game) PlaySound(soundKey string) {
+	if strings.TrimSpace(soundKey) != "" {
+		g.AudioPlayers[soundKey].Rewind()
+		g.AudioPlayers[soundKey].Play()
+	}
+}
+
+func (g *Game) SetVolume(volume float64) {
+	if volume > 1.0 || volume < 0.0 {
+		return
+	}
+
+	g.Config.Volume = volume
+	for _, player := range g.AudioPlayers {
+		player.SetVolume(volume)
+	}
+}
+
+func (g *Game) IncreaseVolume(volumeDelta float64) {
+	for _, player := range g.AudioPlayers {
+		volume := player.Volume() + volumeDelta
+		if volume > 1.0 || volume < 0.0 {
+			continue
+		}
+
+		player.SetVolume(volume)
+		g.Config.Volume = volume
+	}
+}
+
+func (g *Game) DecreaseVolume(volumeDelta float64) {
+	for _, player := range g.AudioPlayers {
+		volume := player.Volume() - volumeDelta
+		if volume > 1.0 || volume < 0.0 {
+			continue
+		}
+
+		player.SetVolume(volume)
+		g.Config.Volume = volume
+	}
+}

src/game/capybara.go

@@ -0,0 +1,73 @@
+package game
+
+import (
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/inpututil"
+)
+
+type Capybara struct {
+	Sprite *Sprite
+}
+
+func NewCapybara(sprite *Sprite) *Capybara {
+	return &Capybara{
+		Sprite: sprite,
+	}
+}
+
+func (c *Capybara) Update() {
+	if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) ||
+		len(inpututil.AppendJustPressedTouchIDs(nil)) != 0 {
+		c.Sprite.Animation.Squish += 0.5
+	}
+
+	// Capybara Animation
+	capyAniData := &c.Sprite.Animation
+	if capyAniData.Theta >= 0.03 {
+		capyAniData.BounceDirectionFlag = false
+	} else if capyAniData.Theta <= -0.03 {
+		capyAniData.BounceDirectionFlag = true
+	}
+
+	if capyAniData.Squish >= 0 {
+		capyAniData.Squish -= 0.05
+	}
+
+	if capyAniData.BounceDirectionFlag {
+		capyAniData.Theta += 0.001
+	} else {
+		capyAniData.Theta -= 0.001
+	}
+}
+
+func (c *Capybara) Draw(screen *ebiten.Image, level uint32) {
+	// Capybara
+	switch level {
+	case 1:
+		c.Sprite.ChangeImageByName("capybara_1.png")
+	case 2:
+		c.Sprite.ChangeImageByName("capybara_2.png")
+	case 3:
+		c.Sprite.ChangeImageByName("capybara_3.png")
+	default:
+		c.Sprite.ChangeImageByName("capybara_3.png")
+	}
+
+	op := &ebiten.DrawImageOptions{}
+	capybaraBounds := c.Sprite.Img.Bounds()
+	scale := float64(screen.Bounds().Dx()) / float64(capybaraBounds.Dx()) / 2.5
+	c.Sprite.Scale = scale
+	op.GeoM.Scale(
+		scale+c.Sprite.Animation.Squish,
+		scale-c.Sprite.Animation.Squish,
+	)
+	op.GeoM.Rotate(c.Sprite.Animation.Theta)
+
+	capyWidth := float64(c.Sprite.RealBounds().Dx())
+	capyHeight := float64(c.Sprite.RealBounds().Dy())
+	c.Sprite.MoveTo(float64(screen.Bounds().Dx()/2)-capyWidth/2, float64(screen.Bounds().Dy()/2)-capyHeight/2)
+
+	op.GeoM.Translate(c.Sprite.X, c.Sprite.Y)
+
+	screen.DrawImage(c.Sprite.Img, op)
+}

src/game/game.go

@@ -9,7 +9,6 @@ import (
 	"fmt"
 	"image/color"
 	"path/filepath"
-	"strings"
 
 	"github.com/hajimehoshi/ebiten/v2"
 	"github.com/hajimehoshi/ebiten/v2/audio"
@@ -19,65 +18,44 @@ import (
 	"golang.org/x/image/font/opentype"
 )
 
-type AnimationData struct {
-	Squish              float64
-	Theta               float64
-	BounceDirectionFlag bool
-}
-
 type Game struct {
 	WorkingDir          string
 	Config              conf.Configuration
 	Save                save.Save
-	AudioContext        *audio.Context
 	AudioPlayers        map[string]*audio.Player
-	ImageResources      map[string]*ebiten.Image
 	FontFace            font.Face
-	AnimationData       AnimationData
 	PassiveIncomeTicker int
+	Capybara            *Capybara
+	Background          *Sprite
+	MandarinRain        *MandarinRain
 }
 
-func NewGame() *Game {
+func NewGame() Game {
 	audioCtx := audio.NewContext(44000)
 	fnt := resources.GetFont("PixeloidSans-Bold.otf")
 
-	return &Game{
+	return Game{
 		WorkingDir: ".",
 		Config:     conf.Default(),
 		Save:       save.Default(),
-		AudioContext: audioCtx,
 		AudioPlayers: map[string]*audio.Player{
 			"boop":                    resources.GetAudioPlayer(audioCtx, "boop.wav"),
 			"woop":                    resources.GetAudioPlayer(audioCtx, "woop.wav"),
 			"menu_switch":             resources.GetAudioPlayer(audioCtx, "menu_switch.wav"),
 			"levelup":                 resources.GetAudioPlayer(audioCtx, "levelup.wav"),
+			"mandarin_box_full":       resources.GetAudioPlayer(audioCtx, "mandarin_box_full.wav"),
+			"orange_put":              resources.GetAudioPlayer(audioCtx, "orange_put.wav"),
+			"mandarin_rain_completed": resources.GetAudioPlayer(audioCtx, "mandarin_rain_completed.wav"),
 		},
-		ImageResources: map[string]*ebiten.Image{
+		Capybara:   NewCapybara(NewSpriteFromFile("capybara_1.png")),
-			"capybara1":   ebiten.NewImageFromImage(resources.ImageFromFile("capybara_1.png")),
+		Background: NewSpriteFromFile("background_1.png"),
-			"capybara2":   ebiten.NewImageFromImage(resources.ImageFromFile("capybara_2.png")),
-			"capybara3":   ebiten.NewImageFromImage(resources.ImageFromFile("capybara_3.png")),
-			"background1": ebiten.NewImageFromImage(resources.ImageFromFile("background_1.png")),
-			"background2": ebiten.NewImageFromImage(resources.ImageFromFile("background_2.png")),
-		},
 		FontFace: util.NewFace(fnt, &opentype.FaceOptions{
 			Size:    32,
 			DPI:     72,
 			Hinting: font.HintingVertical,
 		}),
-		AnimationData: AnimationData{
-			Theta:               0.0,
-			BounceDirectionFlag: true,
-			Squish:              0,
-		},
 		PassiveIncomeTicker: 0,
-	}
+		MandarinRain:        NewMandarinRain(3, 8),
-}
-
-// Plays sound and rewinds the player
-func (g *Game) PlaySound(soundKey string) {
-	if strings.TrimSpace(soundKey) != "" {
-		g.AudioPlayers[soundKey].Rewind()
-		g.AudioPlayers[soundKey].Play()
 	}
 }
 
@@ -99,54 +77,30 @@ func (g *Game) SaveData(saveFileName string, configurationFileName string) error
 	return nil
 }
 
-// Returns how many points required to be considered of level
-func pointsForLevel(level uint32) uint64 {
-	return 25 * uint64(level*level)
-}
-
 func (g *Game) Update() error {
 	if ebiten.IsWindowBeingClosed() {
 		return ebiten.Termination
 	}
 
-	// Update configuration and save information
-	width, height := ebiten.WindowSize()
-	g.Config.WindowSize = [2]int{width, height}
-
-	x, y := ebiten.WindowPosition()
-	g.Config.LastWindowPosition = [2]int{x, y}
-
 	if inpututil.IsKeyJustPressed(ebiten.KeyEscape) {
 		// Exit
 		return ebiten.Termination
 	}
 
 	if inpututil.IsKeyJustPressed(ebiten.KeyF12) {
-		if ebiten.IsFullscreen() {
+		g.ToggleFullscreen()
-			// Turn fullscreen off
-			ebiten.SetFullscreen(false)
-		} else {
-			// Go fullscreen
-			ebiten.SetFullscreen(true)
-		}
 	}
 
+	g.SaveWindowGeometry()
+
 	if inpututil.IsKeyJustPressed(ebiten.KeyArrowLeft) {
 		// Decrease volume
-		if g.Config.Volume-0.2 >= 0 {
+		g.DecreaseVolume(0.2)
-			g.Config.Volume -= 0.2
-			for _, player := range g.AudioPlayers {
-				player.SetVolume(g.Config.Volume)
-			}
 	}
-	} else if inpututil.IsKeyJustPressed(ebiten.KeyArrowRight) {
+
+	if inpututil.IsKeyJustPressed(ebiten.KeyArrowRight) {
 		// Increase volume
-		if g.Config.Volume+0.2 <= 1.0 {
+		g.IncreaseVolume(0.2)
-			g.Config.Volume += 0.2
-			for _, player := range g.AudioPlayers {
-				player.SetVolume(g.Config.Volume)
-			}
-		}
 	}
 
 	if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) ||
@@ -154,21 +108,9 @@ func (g *Game) Update() error {
 		// Click!
 		g.Save.TimesClicked++
 		g.Save.Points++
-		g.AnimationData.Squish += 0.5
 		g.PlaySound("woop")
 	}
 
-	// Capybara Animation
-	if g.AnimationData.Theta >= 0.03 {
-		g.AnimationData.BounceDirectionFlag = false
-	} else if g.AnimationData.Theta <= -0.03 {
-		g.AnimationData.BounceDirectionFlag = true
-	}
-
-	if g.AnimationData.Squish >= 0 {
-		g.AnimationData.Squish -= 0.05
-	}
-
 	// Passive points income
 	if g.PassiveIncomeTicker == ebiten.TPS() {
 		g.PassiveIncomeTicker = 0
@@ -184,6 +126,25 @@ func (g *Game) Update() error {
 		g.PlaySound("levelup")
 	}
 
+	// Capybara animation update
+	g.Capybara.Update()
+
+	if !g.MandarinRain.InProgress && g.Save.TimesClicked > 0 && g.Save.TimesClicked%100 == 0 {
+		// Have some oranges!
+		g.MandarinRain.Run()
+		logger.Info("Started mandarin rain at %d points!", g.Save.Points)
+	}
+
+	if g.MandarinRain.InProgress {
+		// Calculate mandarin rain logic for this step
+		g.MandarinRain.Update(g)
+	}
+
+	if g.MandarinRain.Completed {
+		// Prepare a new mandarin rain
+		g.MandarinRain = NewMandarinRain(3, 8)
+	}
+
 	return nil
 }
 
@@ -191,51 +152,21 @@ func (g *Game) Draw(screen *ebiten.Image) {
 	// Background
 	screen.Fill(color.Black)
 
-	backBounds := g.ImageResources["background1"].Bounds()
 	op := &ebiten.DrawImageOptions{}
 	op.GeoM.Scale(
-		float64(screen.Bounds().Dx())/float64(backBounds.Dx()),
+		float64(screen.Bounds().Dx())/float64(g.Background.Img.Bounds().Dx()),
-		float64(screen.Bounds().Dy())/float64(backBounds.Dy()),
+		float64(screen.Bounds().Dy())/float64(g.Background.Img.Bounds().Dy()),
 	)
-	screen.DrawImage(g.ImageResources["background1"], op)
+	screen.DrawImage(g.Background.Img, op)
 
 	// Capybara
-	var capybaraKey string
+	g.Capybara.Draw(screen, g.Save.Level)
-	switch g.Save.Level {
-	case 1:
-		capybaraKey = "capybara1"
-	case 2:
-		capybaraKey = "capybara2"
-	case 3:
-		capybaraKey = "capybara3"
-	default:
-		capybaraKey = "capybara3"
-	}
 
-	op = &ebiten.DrawImageOptions{}
+	// Mandarin rain
-	if g.AnimationData.BounceDirectionFlag {
+	if g.MandarinRain.InProgress {
-		g.AnimationData.Theta += 0.001
+		g.MandarinRain.Draw(screen)
-	} else {
-		g.AnimationData.Theta -= 0.001
 	}
 
-	capybaraBounds := g.ImageResources[capybaraKey].Bounds()
-	scale := float64(screen.Bounds().Dx()) / float64(capybaraBounds.Dx()) / 2.5
-	op.GeoM.Scale(
-		scale+g.AnimationData.Squish,
-		scale-g.AnimationData.Squish,
-	)
-	op.GeoM.Rotate(g.AnimationData.Theta)
-
-	capyWidth := float64(g.ImageResources[capybaraKey].Bounds().Dx()) * scale
-	capyHeight := float64(g.ImageResources[capybaraKey].Bounds().Dy()) * scale
-	op.GeoM.Translate(
-		float64(screen.Bounds().Dx()/2)-capyWidth/2,
-		float64(screen.Bounds().Dy()/2)-capyHeight/2,
-	)
-
-	screen.DrawImage(g.ImageResources[capybaraKey], op)
-
 	// Points
 	msg := fmt.Sprintf("Points: %d", g.Save.Points)
 	text.Draw(

src/game/level.go

@@ -0,0 +1,6 @@
+package game
+
+// Returns how many points required to be considered of level
+func pointsForLevel(level uint32) uint64 {
+	return 25 * uint64(level*level)
+}

src/game/mandarinRain.go

@@ -0,0 +1,258 @@
+package game
+
+import (
+	"image"
+	"math/rand"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/inpututil"
+)
+
+type MandarinRain struct {
+	InProgress           bool
+	MandarinBox          *Physical
+	Mandarins            []*Physical
+	Completed            bool
+	mandarinCount        uint16
+	mandarinInitialCount uint16
+	mandarinsInBox       uint16
+	boxFull              bool
+	mandarinCountRange   [2]uint16
+	screenBounds         image.Rectangle
+}
+
+func NewMandarinRain(from uint16, to uint16) *MandarinRain {
+	rain := MandarinRain{}
+	rain.screenBounds = WindowBounds()
+	rain.InProgress = false
+	rain.mandarinInitialCount = uint16(rand.Int31n(int32(to-from)) + int32(from))
+	rain.mandarinCountRange = [2]uint16{from, to}
+	rain.mandarinCount = rain.mandarinInitialCount
+	rain.mandarinsInBox = 0
+	rain.boxFull = false
+	rain.Completed = false
+
+	rain.Mandarins = make([]*Physical, rain.mandarinInitialCount)
+	for i := 0; i < int(rain.mandarinInitialCount); i++ {
+		rain.Mandarins[i] = NewPhysical(NewSpriteFromFile("mandarin_orange.png"), 10.0)
+	}
+
+	rain.MandarinBox = NewPhysical(NewSpriteFromFile("mandarin_box_empty.png"), 5.5)
+
+	return &rain
+}
+
+func (mr *MandarinRain) Run() {
+	if mr.InProgress {
+		return
+	}
+
+	mr.screenBounds = WindowBounds()
+	mr.InProgress = true
+
+	// Move oranges to random positions on the top of the screen
+	for _, orange := range mr.Mandarins {
+		orange.Sprite.MoveTo(float64(rand.Int31n(int32(mr.screenBounds.Bounds().Dx()-orange.Sprite.RealBounds().Dx()))), 10.0)
+	}
+
+	// Create mandarin box
+	mr.MandarinBox.Sprite.MoveTo(
+		float64(rand.Int31n(int32(mr.screenBounds.Bounds().Dx()-mr.MandarinBox.Sprite.RealBounds().Dx()))),
+		10.0,
+	)
+}
+
+func (mr *MandarinRain) Update(game *Game) {
+	mr.screenBounds = WindowBounds()
+
+	cPosX, cPosY := ebiten.CursorPosition()
+	var tPosX int = 0
+	var tPosY int = 0
+	if len(ebiten.AppendTouchIDs(nil)) != 0 {
+		tPosX, tPosY = ebiten.TouchPosition(ebiten.AppendTouchIDs(nil)[0])
+	}
+
+	// Oranges
+	temp := mr.Mandarins[:0]
+	for _, orange := range mr.Mandarins {
+		orange.Acceleration.Vx = 0.0
+		orange.Acceleration.Vy = 9.81 / orange.Mass
+
+		if ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) &&
+			orange.InVicinity(float64(cPosX), float64(cPosY), 75.0) {
+			difference := newVec2f(
+				(float64(cPosX-orange.Sprite.RealBounds().Dx()/2)-orange.Sprite.X)*4.5,
+				(float64(cPosY-orange.Sprite.RealBounds().Dy()/2)-orange.Sprite.Y)*4.5,
+			)
+
+			orange.Acceleration.Vx = difference.Vx / orange.Mass
+			orange.Acceleration.Vy = difference.Vy / orange.Mass
+		} else if len(inpututil.AppendJustPressedTouchIDs(nil)) != 0 &&
+			orange.InVicinity(float64(tPosX), float64(tPosY), 75.0) {
+
+			tPosX, tPosY := ebiten.TouchPosition(ebiten.AppendTouchIDs(nil)[0])
+			difference := newVec2f(
+				(float64(tPosX-orange.Sprite.RealBounds().Dx()/2)-orange.Sprite.X)*4.5,
+				(float64(tPosY-orange.Sprite.RealBounds().Dy()/2)-orange.Sprite.Y)*4.5,
+			)
+
+			orange.Acceleration.Vx = difference.Vx / orange.Mass
+			orange.Acceleration.Vy = difference.Vy / orange.Mass
+		}
+
+		orange.Velocity.Vx = orange.Velocity.Vx + orange.Acceleration.Vx*0.05
+		orange.Velocity.Vy = orange.Velocity.Vy + orange.Acceleration.Vy*0.05
+
+		oBounds := orange.Sprite.RealBounds()
+		oX := orange.Sprite.X
+		oY := orange.Sprite.Y
+
+		// Constraints
+		// Right
+		if oX+float64(oBounds.Dx()) >= float64(mr.screenBounds.Dx()) {
+			orange.Velocity.Vx = -orange.Velocity.Vx * 0.4
+		}
+
+		// Left
+		if oX <= 0 {
+			orange.Velocity.Vx = -orange.Velocity.Vx * 0.4
+		}
+
+		// Up
+		if oY <= 0.0 {
+			orange.Velocity.Vy = -orange.Velocity.Vy * 0.4
+		}
+
+		// Bottom
+		if oY+float64(oBounds.Dy()) >= float64(mr.screenBounds.Dy()) {
+			orange.Velocity.Vx = orange.Velocity.Vx * 0.4 // friction on the floor
+			orange.Velocity.Vy = -orange.Velocity.Vy * 0.4
+		}
+
+		orange.Sprite.X += orange.Velocity.Vx
+		orange.Sprite.Y += orange.Velocity.Vy
+
+		// Move the orange
+		orange.Sprite.MoveTo(orange.Sprite.X, orange.Sprite.Y)
+
+		// Check whether it touches mandarin box
+		if orange.InVicinity(mr.MandarinBox.Sprite.X, mr.MandarinBox.Sprite.Y, float64(mr.MandarinBox.Sprite.RealBounds().Dx())) {
+			// Yes!
+			mr.mandarinsInBox++
+			mr.mandarinCount--
+			game.PlaySound("orange_put")
+		} else {
+			// Do not include this orange in the next update (effectively, delete it)
+			temp = append(temp, orange)
+		}
+	}
+	mr.Mandarins = temp
+
+	// Orange box
+	mr.MandarinBox.Acceleration.Vx = 0.0
+	mr.MandarinBox.Acceleration.Vy = 9.81 / mr.MandarinBox.Mass
+
+	if ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) &&
+		mr.MandarinBox.InVicinity(float64(cPosX), float64(cPosY), 75.0) {
+		difference := newVec2f(
+			(float64(cPosX-mr.MandarinBox.Sprite.RealBounds().Dx()/2)-mr.MandarinBox.Sprite.X)*3.5,
+			(float64(cPosY-mr.MandarinBox.Sprite.RealBounds().Dy()/2)-mr.MandarinBox.Sprite.Y)*3.5,
+		)
+
+		mr.MandarinBox.Acceleration.Vx = difference.Vx / mr.MandarinBox.Mass
+		mr.MandarinBox.Acceleration.Vy = difference.Vy / mr.MandarinBox.Mass
+	} else if len(inpututil.AppendJustPressedTouchIDs(nil)) != 0 &&
+		mr.MandarinBox.InVicinity(float64(tPosX), float64(tPosY), 75.0) {
+
+		tPosX, tPosY := ebiten.TouchPosition(ebiten.AppendTouchIDs(nil)[0])
+		difference := newVec2f(
+			(float64(tPosX-mr.MandarinBox.Sprite.RealBounds().Dx()/2)-mr.MandarinBox.Sprite.X)*3.5,
+			(float64(tPosY-mr.MandarinBox.Sprite.RealBounds().Dy()/2)-mr.MandarinBox.Sprite.Y)*3.5,
+		)
+
+		mr.MandarinBox.Acceleration.Vx = difference.Vx / mr.MandarinBox.Mass
+		mr.MandarinBox.Acceleration.Vy = difference.Vy / mr.MandarinBox.Mass
+	}
+
+	mr.MandarinBox.Velocity.Vx = mr.MandarinBox.Velocity.Vx + mr.MandarinBox.Acceleration.Vx*0.05
+	mr.MandarinBox.Velocity.Vy = mr.MandarinBox.Velocity.Vy + mr.MandarinBox.Acceleration.Vy*0.05
+
+	mBounds := mr.MandarinBox.Sprite.RealBounds()
+	mX := mr.MandarinBox.Sprite.X
+	mY := mr.MandarinBox.Sprite.Y
+
+	// Right
+	if mX+float64(mBounds.Dx()) >= float64(mr.screenBounds.Dx()) {
+		mr.MandarinBox.Velocity.Vx = -mr.MandarinBox.Velocity.Vx * 0.3
+	}
+
+	// Left
+	if mX <= 0 {
+		mr.MandarinBox.Velocity.Vx = -mr.MandarinBox.Velocity.Vx * 0.3
+	}
+
+	// Up
+	if mY <= 0.0 {
+		mr.MandarinBox.Velocity.Vy = -mr.MandarinBox.Velocity.Vy * 0.3
+	}
+
+	// Bottom
+	if mY+float64(mBounds.Dy()) >= float64(mr.screenBounds.Dy()) {
+		mr.MandarinBox.Velocity.Vx = mr.MandarinBox.Velocity.Vx * 0.3 // friction on the floor
+		mr.MandarinBox.Velocity.Vy = -mr.MandarinBox.Velocity.Vy * 0.3
+	}
+
+	mr.MandarinBox.Sprite.X += mr.MandarinBox.Velocity.Vx
+	mr.MandarinBox.Sprite.Y += mr.MandarinBox.Velocity.Vy
+
+	// Move box
+	mr.MandarinBox.Sprite.MoveTo(mr.MandarinBox.Sprite.X, mr.MandarinBox.Sprite.Y)
+
+	if mr.mandarinsInBox == mr.mandarinInitialCount && !mr.boxFull {
+		// All oranges are in a box!
+		mr.boxFull = true
+		game.PlaySound("mandarin_box_full")
+	}
+
+	// If the box is full with mandarines and is near capybara - end mandarin rain and reward with points!
+	if mr.boxFull && mr.MandarinBox.InVicinity(
+		game.Capybara.Sprite.X+float64(game.Capybara.Sprite.RealBounds().Dx()/2),
+		game.Capybara.Sprite.Y+float64(game.Capybara.Sprite.RealBounds().Dy()/2),
+		float64(mr.screenBounds.Dx())/7) {
+		// Give a reward and finish this mandarin rain!
+		game.Save.Points += pointsForLevel(game.Save.Level+1) / 5
+		game.PlaySound("mandarin_rain_completed")
+		mr.InProgress = false
+		mr.Completed = true
+	}
+}
+
+func (mr *MandarinRain) Draw(screen *ebiten.Image) {
+	if mr.InProgress {
+		// Mandarin box
+		if mr.mandarinsInBox < mr.mandarinInitialCount && mr.mandarinsInBox > 0 {
+			mr.MandarinBox.Sprite.ChangeImageByName("mandarin_box_not_empty.png")
+		} else if mr.mandarinsInBox == mr.mandarinInitialCount {
+			mr.MandarinBox.Sprite.ChangeImageByName("mandarin_box_full.png")
+		} else {
+			mr.MandarinBox.Sprite.ChangeImageByName("mandarin_box_empty.png")
+		}
+
+		op := &ebiten.DrawImageOptions{}
+		scale := float64(screen.Bounds().Dx()) / float64(mr.MandarinBox.Sprite.Img.Bounds().Dx()) / 6.0
+		mr.MandarinBox.Sprite.Scale = scale // Save current scale for proper collision detection
+		op.GeoM.Scale(scale, scale)
+		op.GeoM.Translate(mr.MandarinBox.Sprite.X, mr.MandarinBox.Sprite.Y)
+		screen.DrawImage(mr.MandarinBox.Sprite.Img, op)
+
+		// Oranges
+		for _, orange := range mr.Mandarins {
+			op = &ebiten.DrawImageOptions{}
+			scale = float64(screen.Bounds().Dx()) / float64(orange.Sprite.Img.Bounds().Dx()) / 11.5
+			orange.Sprite.Scale = scale // Save current scale for proper collision detection
+			op.GeoM.Scale(scale, scale)
+			op.GeoM.Translate(orange.Sprite.X, orange.Sprite.Y)
+			screen.DrawImage(orange.Sprite.Img, op)
+		}
+	}
+}

src/game/physical.go

@@ -0,0 +1,40 @@
+package game
+
+import "math"
+
+type Vec2f struct {
+	Vx float64
+	Vy float64
+}
+
+func newVec2f(x float64, y float64) Vec2f {
+	return Vec2f{
+		Vx: x,
+		Vy: y,
+	}
+}
+
+type Physical struct {
+	Sprite       *Sprite
+	Velocity     Vec2f
+	Acceleration Vec2f
+	Mass         float64
+}
+
+func NewPhysical(sprite *Sprite, mass float64) *Physical {
+	return &Physical{
+		Sprite:       sprite,
+		Velocity:     newVec2f(0.0, 0.0),
+		Acceleration: newVec2f(0.0, 0.0),
+		Mass:         10.0,
+	}
+}
+
+// Returns true if x and y coordinates are in the radius of the physical sprite
+func (ph *Physical) InVicinity(x float64, y float64, radius float64) bool {
+	distance := math.Sqrt(
+		math.Pow(ph.Sprite.X-x, 2.0) + math.Pow(ph.Sprite.Y-y, 2.0),
+	)
+
+	return distance <= radius
+}

src/game/sprite.go

@@ -0,0 +1,92 @@
+package game
+
+import (
+	"Unbewohnte/capyclick/resources"
+	"image"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+type AnimationData struct {
+	Squish              float64
+	Theta               float64
+	BounceDirectionFlag bool
+}
+
+// Drawable image structure
+type Sprite struct {
+	Img       *ebiten.Image
+	X         float64
+	Y         float64
+	Animation AnimationData
+	Scale     float64
+	Dragged   bool
+}
+
+func NewSprite(img image.Image) *Sprite {
+	return &Sprite{
+		Img: ebiten.NewImageFromImage(img),
+		X:   0.0,
+		Y:   0.0,
+		Animation: AnimationData{
+			Squish:              0.0,
+			Theta:               0.0,
+			BounceDirectionFlag: false,
+		},
+		Scale:   1.0,
+		Dragged: false,
+	}
+}
+
+func NewSpriteFromFile(fileName string) *Sprite {
+	return NewSprite(resources.ImageFromFile(fileName))
+}
+
+func (s *Sprite) ChangeImageByName(fileName string) {
+	s.Img = ebiten.NewImageFromImage(resources.ImageFromFile(fileName))
+}
+
+// Returns how big the image is with applied scale factor
+func (s *Sprite) RealBounds() image.Rectangle {
+	bounds := s.Img.Bounds()
+	realBounds := image.Rect(0, 0, bounds.Dx()*int(s.Scale), bounds.Dy()*int(s.Scale))
+	return realBounds
+}
+
+func (s *Sprite) IsIn(x int, y int) bool {
+	if x >= int(s.X) && x <= (int(s.X)+s.RealBounds().Dx()) &&
+		y >= int(s.Y) && y <= (int(s.Y)+s.RealBounds().Dy()) {
+		return true
+	}
+
+	return false
+}
+
+// Moves sprite to given positions. Respects window constraints
+func (s *Sprite) MoveTo(x float64, y float64) {
+	s.X = x
+	s.Y = y
+	screenBounds := WindowBounds()
+
+	// Constraints
+	// Right
+	if s.X+float64(s.RealBounds().Dx()) >= float64(screenBounds.Dx()) {
+		s.X = float64(screenBounds.Dx()) - float64(s.RealBounds().Dx())
+	}
+
+	// Left
+	if s.X <= 0 {
+		s.X = 0
+	}
+
+	// Up
+	if s.Y <= 0.0 {
+		s.Y = 0.0
+	}
+
+	// Bottom
+	if s.Y+float64(s.RealBounds().Dy()) >= float64(screenBounds.Dy()) {
+		s.Y = float64(screenBounds.Dy()) - float64(s.RealBounds().Dy())
+	}
+
+}

src/game/window.go

@@ -0,0 +1,31 @@
+package game
+
+import (
+	"image"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+func (g *Game) ToggleFullscreen() {
+	if ebiten.IsFullscreen() {
+		// Turn fullscreen off
+		ebiten.SetFullscreen(false)
+	} else {
+		// Go fullscreen
+		ebiten.SetFullscreen(true)
+	}
+}
+
+func (g *Game) SaveWindowGeometry() {
+	// Update configuration and save information
+	width, height := ebiten.WindowSize()
+	g.Config.WindowSize = [2]int{width, height}
+
+	x, y := ebiten.WindowPosition()
+	g.Config.LastWindowPosition = [2]int{x, y}
+}
+
+func WindowBounds() image.Rectangle {
+	x, y := ebiten.WindowSize()
+	return image.Rect(0, 0, x, y)
+}

src/main.go

@@ -28,6 +28,7 @@ import (
 	"flag"
 	"fmt"
 	"io"
+	"math/rand"
 	"os"
 	"path/filepath"
 	"time"
@@ -35,7 +36,7 @@ import (
 	"github.com/hajimehoshi/ebiten/v2"
 )
 
-const Version string = "v0.1"
+const Version string = "v0.1-release"
 
 var (
 	silent    *bool = flag.Bool("silent", false, "Set to true in order to discard all logging")
@@ -66,7 +67,7 @@ func main() {
 	}
 
 	// Create a game instance
-	var game *game.Game = game.NewGame()
+	var game game.Game = game.NewGame()
 
 	if *saveFiles {
 		// Work out working directory
@@ -138,8 +139,11 @@ func main() {
 		player.SetVolume(game.Config.Volume)
 	}
 
+	// Set up RNG
+	rand.Seed(time.Now().UnixNano())
+
 	// Run the game
-	err := ebiten.RunGame(game)
+	err := ebiten.RunGame(&game)
 	if err == ebiten.Termination || err == nil {
 		logger.Info("[Main] Shutting down!")
 		if *saveFiles {