diff --git a/examples/smoke/README.md b/examples/smoke/README.md
new file mode 100644
index 0000000000000000000000000000000000000000..ccaf2e0c0dad3beaa630922094def3a14bf51025
--- /dev/null
+++ b/examples/smoke/README.md
@@ -0,0 +1,8 @@
+# Smoke
+
+This example implements a smoke particle effect using sprites. It uses a spritesheet with a CSV
+description.
+
+The art in the spritesheet comes from [Kenney](https://kenney.nl/).
+
+
\ No newline at end of file
diff --git a/examples/smoke/blackSmoke.csv b/examples/smoke/blackSmoke.csv
new file mode 100644
index 0000000000000000000000000000000000000000..7870d7b08d02ed609cc9d40222f444421f50db96
--- /dev/null
+++ b/examples/smoke/blackSmoke.csv
@@ -0,0 +1,25 @@
+1543,1146,362,336
+396,0,398,364
+761,1535,386,342
+795,794,351,367
+394,1163,386,364
+1120,1163,377,348
+795,0,368,407
+0,0,395,397
+1164,0,378,415
+781,1163,338,360
+1543,0,372,370
+1148,1535,393,327
+387,1535,373,364
+396,365,371,388
+0,758,378,404
+379,758,378,371
+1543,774,360,371
+1543,1483,350,398
+0,398,382,359
+1164,416,356,382
+1164,799,369,350
+0,1535,386,394
+795,408,366,385
+1543,371,367,402
+0,1163,393,371
\ No newline at end of file
diff --git a/examples/smoke/blackSmoke.png b/examples/smoke/blackSmoke.png
new file mode 100644
index 0000000000000000000000000000000000000000..c5ebbb8d99561424d90889d7fb7c29b3ed630c06
Binary files /dev/null and b/examples/smoke/blackSmoke.png differ
diff --git a/examples/smoke/main.go b/examples/smoke/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..78dea1a25ab400bbc56adea7325f607eb0dfd28c
--- /dev/null
+++ b/examples/smoke/main.go
@@ -0,0 +1,240 @@
+package main
+
+import (
+ "container/list"
+ "encoding/csv"
+ "fmt"
+ "image"
+ "io"
+ "math"
+ "math/rand"
+ "os"
+ "strconv"
+ "time"
+
+ _ "image/png"
+
+ "github.com/faiface/pixel"
+ "github.com/faiface/pixel/pixelgl"
+ "golang.org/x/image/colornames"
+)
+
+type particle struct {
+ Sprite *pixel.Sprite
+ Pos pixel.Vec
+ Rot, Scale float64
+ Mask pixel.RGBA
+ Data interface{}
+}
+
+type particles struct {
+ Generate func() *particle
+ Update func(dt float64, p *particle) bool
+ SpawnAvg, SpawnDist float64
+
+ parts list.List
+ spawnTime float64
+}
+
+func (p *particles) UpdateAll(dt float64) {
+ p.spawnTime -= dt
+ for p.spawnTime <= 0 {
+ p.parts.PushFront(p.Generate())
+ p.spawnTime += math.Max(0, p.SpawnAvg+rand.NormFloat64()*p.SpawnDist)
+ }
+
+ for e := p.parts.Front(); e != nil; e = e.Next() {
+ part := e.Value.(*particle)
+ if !p.Update(dt, part) {
+ defer p.parts.Remove(e)
+ }
+ }
+}
+
+func (p *particles) DrawAll(t pixel.Target) {
+ for e := p.parts.Front(); e != nil; e = e.Next() {
+ part := e.Value.(*particle)
+
+ part.Sprite.SetMatrix(pixel.IM.
+ Scaled(0, part.Scale).
+ Rotated(0, part.Rot).
+ Moved(part.Pos),
+ )
+ part.Sprite.SetColorMask(part.Mask)
+ part.Sprite.Draw(t)
+ }
+}
+
+type smokeData struct {
+ Vel pixel.Vec
+ Time float64
+ Life float64
+}
+
+type smokeSystem struct {
+ Sheet pixel.Picture
+ Rects []pixel.Rect
+ Orig pixel.Vec
+
+ VelBasis []pixel.Vec
+ VelDist float64
+
+ LifeAvg, LifeDist float64
+}
+
+func (ss *smokeSystem) Generate() *particle {
+ sd := new(smokeData)
+ for _, base := range ss.VelBasis {
+ c := math.Max(0, 1+rand.NormFloat64()*ss.VelDist)
+ sd.Vel += base.Scaled(c)
+ }
+ sd.Vel = sd.Vel.Scaled(1 / float64(len(ss.VelBasis)))
+ sd.Life = math.Max(0, ss.LifeAvg+rand.NormFloat64()*ss.LifeDist)
+
+ p := new(particle)
+ p.Data = sd
+
+ p.Pos = ss.Orig
+ p.Scale = 1
+ p.Mask = pixel.Alpha(1)
+ p.Sprite = pixel.NewSprite(ss.Sheet, ss.Rects[rand.Intn(len(ss.Rects))])
+
+ return p
+}
+
+func (ss *smokeSystem) Update(dt float64, p *particle) bool {
+ sd := p.Data.(*smokeData)
+ sd.Time += dt
+
+ frac := sd.Time / sd.Life
+
+ p.Pos += sd.Vel.Scaled(dt)
+ p.Scale = 0.5 + frac*1.5
+
+ const (
+ fadeIn = 0.2
+ fadeOut = 0.4
+ )
+ if frac < fadeIn {
+ p.Mask = pixel.Alpha(math.Pow(frac/fadeIn, 0.75))
+ } else if frac >= fadeOut {
+ p.Mask = pixel.Alpha(math.Pow(1-(frac-fadeOut)/(1-fadeOut), 1.5))
+ } else {
+ p.Mask = pixel.Alpha(1)
+ }
+
+ return sd.Time < sd.Life
+}
+
+func loadSpriteSheet(sheetPath, descriptionPath string) (sheet pixel.Picture, rects []pixel.Rect, err error) {
+ sheetFile, err := os.Open(sheetPath)
+ if err != nil {
+ return nil, nil, err
+ }
+ defer sheetFile.Close()
+
+ sheetImg, _, err := image.Decode(sheetFile)
+ if err != nil {
+ return nil, nil, err
+ }
+
+ sheet = pixel.PictureDataFromImage(sheetImg)
+
+ descriptionFile, err := os.Open(descriptionPath)
+ if err != nil {
+ return nil, nil, err
+ }
+ defer descriptionFile.Close()
+
+ description := csv.NewReader(descriptionFile)
+ for {
+ record, err := description.Read()
+ if err == io.EOF {
+ break
+ }
+ if err != nil {
+ return nil, nil, err
+ }
+
+ x, _ := strconv.ParseFloat(record[0], 64)
+ y, _ := strconv.ParseFloat(record[1], 64)
+ w, _ := strconv.ParseFloat(record[2], 64)
+ h, _ := strconv.ParseFloat(record[3], 64)
+
+ y = sheet.Bounds().H() - y - h
+
+ rects = append(rects, pixel.R(x, y, x+w, y+h))
+ }
+
+ return sheet, rects, nil
+}
+
+func run() {
+ sheet, rects, err := loadSpriteSheet("blackSmoke.png", "blackSmoke.csv")
+ if err != nil {
+ panic(err)
+ }
+
+ cfg := pixelgl.WindowConfig{
+ Title: "Smoke",
+ Bounds: pixel.R(0, 0, 1024, 768),
+ Resizable: true,
+ VSync: true,
+ }
+ win, err := pixelgl.NewWindow(cfg)
+ if err != nil {
+ panic(err)
+ }
+
+ ss := &smokeSystem{
+ Rects: rects,
+ Orig: 0,
+ VelBasis: []pixel.Vec{pixel.V(-100, 100), pixel.V(100, 100), pixel.V(0, 100)},
+ VelDist: 0.1,
+ LifeAvg: 7,
+ LifeDist: 0.5,
+ }
+
+ p := &particles{
+ Generate: ss.Generate,
+ Update: ss.Update,
+ SpawnAvg: 0.3,
+ SpawnDist: 0.1,
+ }
+
+ batch := pixel.NewBatch(&pixel.TrianglesData{}, sheet)
+
+ var (
+ second = time.Tick(time.Second)
+ frames = 0
+ )
+
+ last := time.Now()
+ for !win.Closed() {
+ dt := time.Since(last).Seconds()
+ last = time.Now()
+
+ p.UpdateAll(dt)
+
+ win.Clear(colornames.Aliceblue)
+ win.SetMatrix(pixel.IM.Moved(win.Bounds().Center() - pixel.Y(win.Bounds().H()/2)))
+
+ batch.Clear()
+ p.DrawAll(batch)
+ batch.Draw(win)
+
+ win.Update()
+
+ frames++
+ select {
+ case <-second:
+ win.SetTitle(fmt.Sprintf("%s | FPS: %d", cfg.Title, frames))
+ frames = 0
+ default:
+ }
+ }
+}
+
+func main() {
+ pixelgl.Run(run)
+}
diff --git a/examples/smoke/screenshot.png b/examples/smoke/screenshot.png
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index 0000000000000000000000000000000000000000..6cf005641e06f797bd9bad34b744fc4047f507a4
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