package main import ( "bytes" _ "embed" "fmt" "image" "image/color" _ "image/png" "log" "math" "github.com/hajimehoshi/ebiten/v2" _ "github.com/hajimehoshi/ebiten/v2/ebitenutil" "github.com/hajimehoshi/ebiten/v2/inpututil" "github.com/hajimehoshi/ebiten/v2/vector" "github.com/hajimehoshi/ebiten/v2/text/v2" "github.com/hajimehoshi/ebiten/v2/examples/resources/fonts" "github.com/hajimehoshi/ebiten/v2/audio" "github.com/hajimehoshi/ebiten/v2/audio/wav" "github.com/hajimehoshi/ebiten/v2/audio/vorbis" ) const ( screenWidth = 400 screenHeight = 240 tileSize = 16 playerSpeed = 2.1 jumpHeight = 4 gravity = 0.16 friction = 0.75 airResistance = 0.98 endCardDuration = 240 exitTransitionWeight = 0.7 ghostAlpha = 0.5 hightlightBorder = 2 audioFadeIn = 0.99 musicVolume = 0.3 sampleRate = 44100 shadowOffset = 1 killPlayerAfter = 80 musicLoopLength = 230 menuFadeInTime = 80 buttonOffset = 4.0 buttonOffsetPressed = 2.0 ) var ( //go:embed shaders/none.kage noneShader_src []byte //go:embed shaders/vcr.kage vcrShader_src []byte //go:embed shaders/clouds.kage cloudShader_src []byte //go:embed shaders/bloom.kage bloomShader_src []byte //go:embed assets/tiles.png tilesPng_src []byte //go:embed assets/character.png characterPng_src []byte //go:embed assets/rewind.wav rewindWav_src []byte //go:embed assets/stop.wav stopWav_src []byte //go:embed assets/start.wav startWav_src []byte //go:embed assets/ambient.ogg ambientOgg_src []byte //go:embed assets/spring.ogg springOgg_src []byte //go:embed assets/jump1.ogg jump1Ogg_src []byte //go:embed assets/jump2.ogg jump2Ogg_src []byte //go:embed assets/land1.ogg land1Ogg_src []byte //go:embed assets/land2.ogg land2Ogg_src []byte //go:embed assets/vo/voice1.ogg voice1Ogg_src []byte //go:embed assets/vo/voice2.ogg voice2Ogg_src []byte //go:embed assets/vo/voice3.ogg voice3Ogg_src []byte //go:embed assets/vo/voice4.ogg voice4Ogg_src []byte //go:embed assets/vo/voice5.ogg voice5Ogg_src []byte //go:embed assets/vo/voice6.ogg voice6Ogg_src []byte //go:embed assets/vo/voice7.ogg voice7Ogg_src []byte ) var ( shaders map[string]*ebiten.Shader tilesImage *ebiten.Image characterImage *ebiten.Image fontFaceSource *text.GoTextFaceSource rewindSpeed = 2 bx, by, bw, bh float32 bo float32 = buttonOffset ) type State int const ( MENU State = iota IN_GAME END PLACING PAUSED REVERSING ) type RecPoint struct { x float32 y float32 vx float32 vy float32 alpha float32 delta int state int } type AudioPlayer struct { audioContext *audio.Context rewindAudio *audio.Player stopAudio *audio.Player startAudio *audio.Player ambientAudio *audio.Player springAudio *audio.Player jumpAudio []*audio.Player landAudio []*audio.Player voiceAudio []*audio.Player } type Game struct { surface *ebiten.Image tilemap *Tilemap offsetX int offsetY int player *GameObject startPosition *GameObject exit *GameObject objects []*GameObject time int animStart int shaderName string recording [][]RecPoint state State toPlace []*GameObject whenStateFinished []func(g *Game) playerAi [][3]bool playerAiIdx int audioPlayer *AudioPlayer } func (g * Game)RecordPoint() { points := []RecPoint{} for _, object := range g.objects { points = append(points, RecPoint{ x: object.x, y: object.y, vx: object.vx, vy: object.vy, alpha: object.alpha, delta: object.delta, state: object.state, }) } g.recording = append(g.recording, points) } func (g * Game)ReplayPoint() { if len(g.recording) == 0 { return } var points []RecPoint points, g.recording = g.recording[len(g.recording)-1], g.recording[:len(g.recording)-1] for i, point := range points { obj := g.objects[i] obj.x = point.x obj.y = point.y obj.vx = point.vx obj.vy = point.vy obj.alpha = point.alpha obj.delta = point.delta obj.state = point.state } } func (g * Game)ResetPlayerAi() { g.playerAiIdx = 0 g.player.x = g.player.startx g.player.y = g.player.starty g.player.vx = 0 g.player.vy = 0 g.player.alpha = ghostAlpha } func (g * Game)ReplayPlayerAi() { if len(g.playerAi) == 0 { return } var state [3]bool if g.playerAiIdx >= len(g.playerAi) { state = g.playerAi[len(g.playerAi) - 1] } else { state = g.playerAi[g.playerAiIdx] } if state[0] { g.player.MoveLeft() } if state[1] { g.player.MoveRight() } if state[2] { g.player.Jump() } g.playerAiIdx += 1 if g.playerAiIdx >= len(g.playerAi) + killPlayerAfter { g.KillPlayer() } } func (g * Game) ClearAll() { g.objects = g.objects[:0] g.objects = append(g.objects, g.player) g.objects = append(g.objects, g.exit) } func (g * Game) ResetAll() { for _, obj := range g.objects { obj.x = obj.startx obj.y = obj.starty obj.vx = 0 obj.vy = 0 obj.delta = 0 obj.highlight = false } g.recording = g.recording[:0]; } func (g *Game) Init() { g.surface = ebiten.NewImage(screenWidth, screenHeight) g.shaderName = "sky" g.state = MENU g.audioPlayer.ambientAudio.SetVolume(0) ebiten.SetWindowSize(screenWidth*2, screenHeight*2) ebiten.SetWindowTitle("Reverse") if err := ebiten.RunGame(g); err != nil { log.Fatal(err) } } func (g *Game) SetEditingMode() { g.SetPlacing() //g.playerAi = g.playerAi[:0] g.ResetAll() g.playerAiIdx = 0 } func (g *Game) Update() error { g.time += 1 if g.state == MENU { if float32(g.time) > menuFadeInTime { cx, cy := ebiten.CursorPosition() onButton := float32(cx) > bx && float32(cy) > by && float32(cx) < bx + bw && float32(cy) < by + bh if inpututil.IsMouseButtonJustPressed(ebiten.MouseButton0) { if onButton { bo = buttonOffsetPressed } else { bo = buttonOffset } } if inpututil.IsMouseButtonJustReleased(ebiten.MouseButton0) { bo = buttonOffset if onButton && g.animStart <= 0{ g.animStart = g.time + 60 g.audioPlayer.landAudio[0].Rewind() g.audioPlayer.landAudio[0].Play() StartGame(g) } } } } if g.state == MENU || g.state == IN_GAME || g.state == PLACING { if g.audioPlayer.ambientAudio.Position().Seconds() > musicLoopLength { g.audioPlayer.ambientAudio.Rewind() } if ! g.audioPlayer.ambientAudio.IsPlaying() { g.audioPlayer.ambientAudio.Play() } volume := g.audioPlayer.ambientAudio.Volume() volume = musicVolume-((musicVolume-volume)*audioFadeIn) g.audioPlayer.ambientAudio.SetVolume(volume) } if g.state == PAUSED && inpututil.IsKeyJustPressed(ebiten.KeyR) { g.TransitionState() } if g.state == IN_GAME { if inpututil.IsKeyJustPressed(ebiten.KeyE) { g.SetEditingMode() } if inpututil.IsKeyJustPressed(ebiten.KeyR) { g.SetReversing() next := func (g *Game){ g.SetInGame() g.recording = g.recording[:0] g.playerAi = g.playerAi[:0] } g.whenStateFinished = append([]func(*Game){next}, g.whenStateFinished...) } var currentState [3]bool if ebiten.IsKeyPressed(ebiten.KeyLeft) || ebiten.IsKeyPressed(ebiten.KeyA) { g.player.MoveLeft() currentState[0] = true } else { currentState[0] = false } if ebiten.IsKeyPressed(ebiten.KeyRight) || ebiten.IsKeyPressed(ebiten.KeyD) { g.player.MoveRight() currentState[1] = true } else { currentState[1] = false } if (ebiten.IsKeyPressed(ebiten.KeySpace) || ebiten.IsKeyPressed(ebiten.KeyUp)) { g.player.Jump() currentState[2] = true } else { currentState[2] = false } g.playerAi = append(g.playerAi, currentState) for _, obj := range g.objects { obj.Update(*g.tilemap, g.objects) obj.highlight = false } g.tilemap.Update() g.RecordPoint() } if g.state == REVERSING { g.time -= 1 + rewindSpeed; if g.time < g.animStart || g.animStart <= 0{ for x := 0; x < rewindSpeed; x++ { g.ReplayPoint() } if len(g.recording) == 0 { g.TransitionState() } } } if g.state == PLACING { g.UpdatePlacing() } if g.player != nil && g.player.y > screenHeight { g.KillPlayer() } return nil } func (g *Game) UpdatePlacing() { for _, obj := range g.objects { obj.Update(*g.tilemap, g.objects) } g.tilemap.Update() g.ReplayPlayerAi() cx, cy := ebiten.CursorPosition() for _, object := range g.objects { object.highlight = object.CollidePoint(float32(cx), float32(cy)) && object.movable && len(g.toPlace) == 0 } if len(g.toPlace) > 0 { placeable := g.toPlace[0] cx = int(math.Floor(float64(cx)/float64(g.tilemap.tileSize)))*g.tilemap.tileSize cy = int(math.Floor(float64(cy)/float64(g.tilemap.tileSize)))*g.tilemap.tileSize cx += placeable.offsetX cy += placeable.offsetY placeable.x = float32(cx) placeable.y = float32(cy) placeable.alpha = float32(math.Abs(math.Sin(float64(g.time) / 30.0))) } if inpututil.IsMouseButtonJustPressed(ebiten.MouseButton0) { g.PlaceObject(cx, cy) } } func (g *Game) PlaceObject(cx, cy int) { if len(g.toPlace) == 0 { object := GetObjectAt(g.objects, float32(cx), float32(cy)) if object != nil { if object.movable { g.toPlace = append([]*GameObject{object}, g.toPlace...) g.RemoveObject(object) } } return } placeable := g.toPlace[0] if placeable.HasCollision(*g.tilemap, g.objects, NONE) { return } placeable.delta = 0 placeable.startx = float32(cx) placeable.starty = float32(cy) placeable.highlight = false placeable.alpha = 1.0 g.objects = append(g.objects, placeable) g.toPlace = g.toPlace[1:len(g.toPlace)] placeable.PlayLand() if len(g.toPlace) == 0 && len(g.playerAi) == 0 { g.TransitionState() } } func DrawBackground(screen *ebiten.Image, time int) { shop := &ebiten.DrawRectShaderOptions{} shop.Uniforms = map[string]any{ "Time": float32(time) / 60, } screen.DrawRectShader(screenWidth, screenHeight, shaders["sky"], shop) } func PostProcess(screen *ebiten.Image, shaderName string, time int) { w, h := screen.Bounds().Dx(), screen.Bounds().Dy() for _, shader := range []string{shaderName} { out := ebiten.NewImage(w, h) shop := &ebiten.DrawRectShaderOptions{} shop.Uniforms = map[string]any{ "Time": float32(time) / 60, "NoiseOffset": float32(time) / 60, } shop.Images[0] = screen shop.Images[1] = screen shop.Images[2] = screen shop.Images[3] = screen out.DrawRectShader(w, h, shaders[shader], shop) op := &ebiten.DrawImageOptions{} screen.DrawImage(out, op) } } func (g *Game) DrawVCRControls(surface *ebiten.Image) { textSize := 15.0 var msg string if g.state == REVERSING { msg = fmt.Sprintf("<<") } else { msg = fmt.Sprintf("||") } textOp := &text.DrawOptions{} textOp.GeoM.Translate(15, 15) textOp.ColorScale.ScaleWithColor(color.RGBA{255, 255, 255, 255}) text.Draw(surface, msg, &text.GoTextFace{ Size: textSize, Source: fontFaceSource, }, textOp) } func (g *Game) DrawTheEnd(surface *ebiten.Image, alpha float32) { textSize := 30.0 msg := fmt.Sprintf("THE END") textOp := &text.DrawOptions{} textOp.GeoM.Translate((screenWidth - textSize*7 ) / 2, (screenHeight - textSize) / 2) textOp.ColorScale.ScaleWithColor(color.RGBA{55, 53, 53, 255}) textOp.ColorScale.ScaleAlpha(alpha) text.Draw(surface, msg, &text.GoTextFace{ Size: textSize, Source: fontFaceSource, }, textOp) } func (g *Game) DrawTitle(surface *ebiten.Image, alpha float32) { textSize := 30.0 tmp := ebiten.NewImage(screenWidth, screenHeight) msg := fmt.Sprintf("LEVEL") textOp := &text.DrawOptions{} textOp.GeoM.Translate((screenWidth - textSize*5 ) / 2, (screenHeight - textSize) / 3) textOp.ColorScale.ScaleWithColor(color.RGBA{216, 211, 210, 255}) text.Draw(tmp, msg, &text.GoTextFace{ Size: textSize, Source: fontFaceSource, }, textOp) ShadowDraw(surface, tmp, 0, 0, alpha) } func (g *Game) DrawStart(surface *ebiten.Image, alpha float32) { msg := fmt.Sprintf("play") tmp := ebiten.NewImage(screenWidth, screenHeight) var textSize float32 = 15.0 var x, y float32 = (screenWidth - textSize*5 ) / 2 + bo/2, (screenHeight + textSize) / 3 + screenHeight / 3 + bo/2 var padding float32 = 5.0 c := color.RGBA{55, 53, 53, 255} bx, by, bw, bh = x - padding, y - padding, (2*padding + float32(len(msg))*textSize) , (2.0*padding + textSize) vector.DrawFilledRect(tmp, bx, by, bw, bh, c, false) c = color.RGBA{79, 78, 78, 255} vector.DrawFilledRect(tmp, bx-bo, by-bo, bw, bh, c, false) textOp := &text.DrawOptions{} textOp.GeoM.Translate(float64(x-bo), float64(y-bo)) textOp.ColorScale.ScaleWithColor(color.RGBA{216, 211, 210, 255}) //textOp.ColorScale.ScaleAlpha(alpha) textOp.Filter = ebiten.FilterNearest text.Draw(tmp, msg, &text.GoTextFace{ Size: float64(textSize), Source: fontFaceSource, }, textOp) op := &ebiten.DrawImageOptions{} op.ColorScale.ScaleAlpha(alpha) surface.DrawImage(tmp, op) } func (g *Game) IsShowTheEnd() bool { return g.animStart > 0 && (g.state == END || g.state == PAUSED || g.state == REVERSING) } func (g *Game) Draw(screen *ebiten.Image) { DrawBackground(screen, g.time) if g.state == MENU { var scale float32 = 1.0 delta := float32(g.time) if g.animStart > 0 { delta = float32((g.animStart+menuFadeInTime) - g.time) scale = 0.5 } if g.tilemap != nil { polation := float32(math.Pow(float64(delta*scale)/menuFadeInTime, 3))*screenHeight g.tilemap.Draw(screen, 0, polation - 2) } alpha := float32(delta) * scale / (menuFadeInTime/2.0) if alpha > 1.0 { alpha = 1.0 } g.DrawTitle(screen, alpha) alpha = float32(delta - (menuFadeInTime/2.0)) * scale / (menuFadeInTime/2.0) if alpha > 1.0 { alpha = 1.0 } g.DrawStart(screen, alpha) if g.animStart > 0 && delta <= 0 { g.animStart = 0 g.SetInGame() } return } g.surface.Fill(color.RGBA{0, 0, 0, 0}) g.tilemap.Draw(g.surface, 0, -2) for i := len(g.objects)-1; i >= 0; i-- { obj := g.objects[i] obj.Draw(obj, g.surface, *g.tilemap) } if g.state == PLACING { if len(g.toPlace) > 0 { g.toPlace[0].Draw(g.toPlace[0], g.surface, *g.tilemap) } } op := &ebiten.DrawImageOptions{} op.GeoM.Translate(float64(g.offsetX), float64(g.offsetY)) if g.IsShowTheEnd() { // draw THE END a := float64(endCardDuration - (g.time - g.animStart)) / float64(endCardDuration); a = 1 - float64(math.Pow(float64(a), 2)) if g.state == PAUSED { a = 1.0 } if a < 0.0 { a = 0.0 } op.GeoM.Translate(float64(g.offsetX), float64(g.offsetY) + a*screenHeight/2) screen.DrawImage(g.surface, op) g.DrawTheEnd(screen, float32(a)) // AFTER THE END if g.state == END && g.time - g.animStart > endCardDuration { g.TransitionState() } } else { screen.DrawImage(g.surface, op) } if g.state == REVERSING || g.state == PAUSED { g.DrawVCRControls(screen) } PostProcess(screen, g.shaderName, g.time) //ebitenutil.DebugPrint(screen, fmt.Sprintf("tps: %.4f", ebiten.ActualFPS())) } func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int){ return screenWidth, screenHeight } func LoadShaders() error { if shaders == nil { shaders = map[string]*ebiten.Shader{} } var err error shaders["none"], err = ebiten.NewShader([]byte(noneShader_src)) if err != nil { return err } shaders["vcr"], err = ebiten.NewShader([]byte(vcrShader_src)) if err != nil { return err } shaders["bloom"], err = ebiten.NewShader([]byte(bloomShader_src)) if err != nil { return err } shaders["sky"], err = ebiten.NewShader([]byte(cloudShader_src)) if err != nil { return err } return nil } func (g *Game) KillPlayer() { if g.state == IN_GAME { g.ResetAll() g.playerAi = g.playerAi[:0] } else { g.playerAiIdx = 0 g.player.x = g.player.startx g.player.y = g.player.starty g.player.vx = 0 g.player.vy = 0 if len(g.toPlace) == 0 { g.ResetAll() g.playerAi = g.playerAi[:0] g.SetInGame() } } } func (g *Game) EndLevel() { if g.state == IN_GAME { g.state = END g.TransitionState() } if g.state == PLACING { g.ResetPlayerAi() } } func (g *Game)RemoveObject(obj *GameObject) { i := 0 // output index for _, x := range g.objects { if x != obj { // copy and increment index g.objects[i] = x i++ } } // Prevent memory leak by erasing truncated values // (not needed if values don't contain pointers, directly or indirectly) for j := i; j < len(g.objects); j++ { g.objects[j] = nil } g.objects = g.objects[:i] } func (g *Game) SetPaused() { g.state = PAUSED g.shaderName = "vcr" //g.player.alpha = 1.0 g.audioPlayer.startAudio.Rewind() g.audioPlayer.startAudio.Play() g.audioPlayer.ambientAudio.Pause() } func (g *Game) SetReversing() { g.state = REVERSING rewindSpeed = 1 + int(len(g.recording) / 120) g.shaderName = "vcr" g.player.alpha = 1.0 g.audioPlayer.rewindAudio.Rewind() g.audioPlayer.rewindAudio.Play() g.audioPlayer.ambientAudio.Pause() } func (g *Game) StopRewinding() { g.shaderName = "none" if g.audioPlayer.rewindAudio.IsPlaying() { g.audioPlayer.rewindAudio.Pause() g.audioPlayer.startAudio.Rewind() g.audioPlayer.startAudio.Play() g.audioPlayer.ambientAudio.Play() } } func (g *Game) SetInGame() { g.state = IN_GAME g.player.alpha = 1.0 g.StopRewinding() } func (g *Game) SetPlacing() { g.state = PLACING g.player.alpha = ghostAlpha g.StopRewinding() } func loadAudiosVorbis(oggFiles [][]byte, audioContext *audio.Context) []*audio.Player { var players = make([]*audio.Player, 0) for _, x := range oggFiles { var err error sound, err := vorbis.DecodeWithoutResampling(bytes.NewReader(x)) if err != nil { return nil } p, err := audioContext.NewPlayer(sound) if err != nil { return nil } players = append(players, p) } return players } func loadAudioVorbis(oggFile []byte, audioContext *audio.Context) *audio.Player { var err error sound, err := vorbis.DecodeWithoutResampling(bytes.NewReader(oggFile)) if err != nil { return nil } p, err := audioContext.NewPlayer(sound) if err != nil { return nil } return p } func loadAudio(wavFile []byte, audioContext *audio.Context) *audio.Player { var err error sound, err := wav.DecodeWithoutResampling(bytes.NewReader(wavFile)) if err != nil { return nil } p, err := audioContext.NewPlayer(sound) if err != nil { return nil } return p } func (g *Game) LoadAudio() { g.audioPlayer = &AudioPlayer{} g.audioPlayer.audioContext = audio.NewContext(sampleRate) g.audioPlayer.rewindAudio = loadAudio(rewindWav_src, g.audioPlayer.audioContext) g.audioPlayer.stopAudio = loadAudio(stopWav_src, g.audioPlayer.audioContext) g.audioPlayer.startAudio = loadAudio(startWav_src, g.audioPlayer.audioContext) g.audioPlayer.ambientAudio = loadAudioVorbis(ambientOgg_src, g.audioPlayer.audioContext) g.audioPlayer.springAudio = loadAudioVorbis(springOgg_src, g.audioPlayer.audioContext) g.audioPlayer.jumpAudio = loadAudiosVorbis([][]byte{jump1Ogg_src, jump2Ogg_src}, g.audioPlayer.audioContext) g.audioPlayer.landAudio = loadAudiosVorbis([][]byte{land1Ogg_src, land2Ogg_src}, g.audioPlayer.audioContext) g.audioPlayer.voiceAudio = loadAudiosVorbis([][]byte{ voice1Ogg_src, voice2Ogg_src, voice3Ogg_src, voice4Ogg_src, voice5Ogg_src, voice6Ogg_src, voice7Ogg_src, }, g.audioPlayer.audioContext) } func (g *Game) LoadImages() { s, err := text.NewGoTextFaceSource(bytes.NewReader(fonts.PressStart2P_ttf)) if err != nil { log.Fatal(err) } fontFaceSource = s img, _, err := image.Decode(bytes.NewReader(characterPng_src)) if err != nil { log.Fatal(err) } characterImage = ebiten.NewImageFromImage(img) img, _, err = image.Decode(bytes.NewReader(tilesPng_src)) if err != nil { log.Fatal(err) } tilesImage = ebiten.NewImageFromImage(img) } func main() { err := LoadShaders() if err != nil { log.Fatal(err) } ebiten.SetWindowTitle("Hello, World!") game := &Game{} game.LoadAudio() game.LoadImages() game.Init() if err := ebiten.RunGame(game); err != nil { log.Fatal(err) } } func (g *Game) TransitionState() { if len(g.whenStateFinished) > 0 { var function func(*Game) g.whenStateFinished, function = g.whenStateFinished[1:len(g.whenStateFinished)], g.whenStateFinished[0] function(g) } } func (g *Game) QueueState(function func(g *Game)) { g.whenStateFinished = append(g.whenStateFinished, function) }