Merge pull request #14 from zcking/feature/tilemap-example

refactored to use batch rendering

community/tilemap/main.go

@@ -16,14 +16,20 @@ import (
 
 var clearColor = colornames.Skyblue
 
-var sprites []*pixel.Sprite
-
 func gameloop(win *pixelgl.Window, tilemap *tmx.Map) {
+ batches := make([]*pixel.Batch, 0)
+ batchIndices := make(map[string]int)
+ batchCounter := 0
+
  // Load the sprites
  sprites := make(map[string]*pixel.Sprite)
  for _, tileset := range tilemap.Tilesets {
  if _, alreadyLoaded := sprites[tileset.Image.Source]; !alreadyLoaded {
- sprites[tileset.Image.Source] = loadSprite(tileset.Image.Source)
+ sprite, pictureData := loadSprite(tileset.Image.Source)
+ sprites[tileset.Image.Source] = sprite
+ batches = append(batches, pixel.NewBatch(&pixel.TrianglesData{}, pictureData))
+ batchIndices[tileset.Image.Source] = batchCounter
+ batchCounter++
  }
  }
 
@@ -59,6 +65,10 @@ func gameloop(win *pixelgl.Window, tilemap *tmx.Map) {
  win.Clear(clearColor)
 
  // Draw tiles
+ for _, batch := range batches {
+ batch.Clear()
+ }
+
  for _, layer := range tilemap.Layers {
  for tileIndex, tile := range layer.DecodedTiles {
  ts := layer.Tileset
@@ -82,10 +92,13 @@ func gameloop(win *pixelgl.Window, tilemap *tmx.Map) {
  sprite := sprites[ts.Image.Source]
  sprite.Set(sprite.Picture(), pixel.R(iX, iY, fX, fY))
  pos := gamePos.ScaledXY(pixel.V(float64(ts.TileWidth), float64(ts.TileHeight)))
- sprite.Draw(win, pixel.IM.Moved(pos))
+ sprite.Draw(batches[batchIndices[ts.Image.Source]], pixel.IM.Moved(pos))
  }
  }
 
+ for _, batch := range batches {
+ batch.Draw(win)
+ }
  win.Update()
  }
 }
@@ -123,15 +136,15 @@ func run() {
  gameloop(win, tilemap)
 }
 
-func loadSprite(path string) *pixel.Sprite {
+func loadSprite(path string) (*pixel.Sprite, *pixel.PictureData) {
  f, err := os.Open(path)
  panicIfErr(err)
 
  img, err := png.Decode(f)
  panicIfErr(err)
 
  pd := pixel.PictureDataFromImage(img)
- return pixel.NewSprite(pd, pd.Bounds())
+ return pixel.NewSprite(pd, pd.Bounds()), pd
 }
 
 func main() {