Revert "Another sprite optimization experiment. (#139)"

This reverts commit a9136eda0a.

d2render/sprite.go

@@ -2,6 +2,7 @@ package d2render
 
 import (
 	"encoding/binary"
+	"image"
 	"image/color"
 	"log"
 	"sync"
@@ -18,7 +19,9 @@ import (
 type Sprite struct {
 	Directions         uint32
 	FramesPerDirection uint32
-	Frames             []*SpriteFrame
+	atlas              *ebiten.Image
+	atlasBytes         []byte
+	Frames             []SpriteFrame
 	SpecialFrameTime   int
 	StopOnLastFrame    bool
 	X, Y               int
@@ -70,14 +73,14 @@ func CreateSprite(data []byte, palette d2datadict.PaletteRec) Sprite {
 		framePointers[i] = binary.LittleEndian.Uint32(data[dataPointer : dataPointer+4])
 		dataPointer += 4
 	}
-	result.Frames = make([]*SpriteFrame, totalFrames)
+	result.Frames = make([]SpriteFrame, totalFrames)
 	wg := sync.WaitGroup{}
 	wg.Add(int(totalFrames))
 	for i := uint32(0); i < totalFrames; i++ {
 		go func(i uint32) {
 			defer wg.Done()
 			dataPointer := framePointers[i]
-			result.Frames[i] = &SpriteFrame{}
+			result.Frames[i] = SpriteFrame{}
 			result.Frames[i].Flip = binary.LittleEndian.Uint32(data[dataPointer : dataPointer+4])
 			dataPointer += 4
 			result.Frames[i].Width = binary.LittleEndian.Uint32(data[dataPointer : dataPointer+4])
@@ -152,6 +155,22 @@ func CreateSprite(data []byte, palette d2datadict.PaletteRec) Sprite {
 		}
 		totalWidth += curMaxWidth
 	}
+	result.atlas, _ = ebiten.NewImage(totalWidth, totalHeight, ebiten.FilterNearest)
+	result.atlasBytes = make([]byte, totalWidth*totalHeight*4)
+	frame = 0
+	curX := 0
+	curY := 0
+	for d := 0; d < int(result.Directions); d++ {
+		curMaxWidth := 0
+		for f := 0; f < int(result.FramesPerDirection); f++ {
+			curMaxWidth = int(d2helper.Max(uint32(curMaxWidth), result.Frames[frame].Width))
+			result.Frames[frame].Image = result.atlas.SubImage(image.Rect(curX, curY, curX+int(result.Frames[frame].Width), curY+int(result.Frames[frame].Height))).(*ebiten.Image)
+			curY += int(result.Frames[frame].Height)
+			frame++
+		}
+		curX += curMaxWidth
+		curY = 0
+	}
 	result.valid = true
 	return result
 }
@@ -164,9 +183,22 @@ func (v *Sprite) cacheFrame(frame int) {
 	if v.Frames[frame].cached {
 		return
 	}
-	v.Frames[frame].Image, _ = ebiten.NewImage(int(v.Frames[frame].Width), int(v.Frames[frame].Height), ebiten.FilterNearest)
+	r := v.Frames[frame].Image.Bounds().Min
-	if err := v.Frames[frame].Image.ReplacePixels(v.Frames[frame].FrameData); err != nil {
+	curX := r.X
-		log.Panicf(err.Error())
+	curY := r.Y
+	totalWidth := v.atlas.Bounds().Max.X
+	for y := 0; y < int(v.Frames[frame].Height); y++ {
+		for x := 0; x < int(v.Frames[frame].Width); x++ {
+			pix := (x + (y * int(v.Frames[frame].Width))) * 4
+			idx := (curX + x + ((curY + y) * totalWidth)) * 4
+			v.atlasBytes[idx] = v.Frames[frame].FrameData[pix]
+			v.atlasBytes[idx+1] = v.Frames[frame].FrameData[pix+1]
+			v.atlasBytes[idx+2] = v.Frames[frame].FrameData[pix+2]
+			v.atlasBytes[idx+3] = v.Frames[frame].FrameData[pix+3]
+		}
+	}
+	if err := v.atlas.ReplacePixels(v.atlasBytes); err != nil {
+		log.Panic(err.Error())
 	}
 	v.Frames[frame].cached = true
 }