feat: splitsprite 增加白底移除、固定网格拆分与帧居中功能

- 新增 RemoveWhiteBg：纯白色背景(#FFFFFF)像素半透明化 - 新增 fixedGridSplit：GridRows×GridCols 固定网格拆分 - 新增 CenterAlign：帧内容居中对齐，确保人物不跳帧 - Options 新增 WhiteBg/GridRows/GridCols/GridPadding/CenterAlign - 默认模式从绿幕切换为白底 - 新增 tools/test_prompt_to_gif.go 端到端测试脚本 - .gitignore 忽略 test_output 目录
2026-05-25 16:48:48 +08:00
parent aff48b6780
commit f3dfcd3b0b
3 changed files with 373 additions and 6 deletions
@@ -0,0 +1,184 @@
+//go:build ignore
+
+package main
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"image"
+	"image/color"
+	"image/draw"
+	"image/gif"
+	"image/png"
+	"os"
+
+	"gen2d/internal/config"
+	"gen2d/internal/service"
+	"gen2d/pkg/splitsprite"
+)
+
+func main() {
+	cfg := config.Load()
+	service.InitLLMConfig(cfg.LLM)
+	service.InitImageGenConfig(cfg.ImageGen)
+
+	ctx := context.Background()
+
+	// 1. PromptAgent 优化提示词
+	fmt.Println("=== Step 1: Optimize prompt via PromptAgent ===")
+	agentIn := service.PromptAgentInput{
+		Tags:      []string{"像素", "战士", "持剑", "精灵表"},
+		AssetType: "sprite",
+		Prompt:    "生成一个像素风持剑战士的4方向行走精灵表",
+		UserNote:  "需要4方向（上下左右），每方向4帧行走动画",
+	}
+	out, err := service.RunPromptAgent(ctx, agentIn)
+	if err != nil {
+		fatalf("PromptAgent failed: %v", err)
+	}
+	fmt.Printf("Optimized prompt:\n%s\n\n", out.Prompt)
+
+	// 2. 调用文生图 API
+	fmt.Println("=== Step 2: Generate sprite sheet via image API ===")
+	params := service.AssetParams{
+		Resolution: 1024,
+		Format:     "spritesheet",
+	}
+	images, err := service.GenerateImages(ctx, out.Prompt, params)
+	if err != nil {
+		fatalf("GenerateImages failed: %v", err)
+	}
+	if len(images) == 0 {
+		fatalf("no images generated")
+	}
+	fmt.Printf("Generated %d image(s), size=%dx%d\n", len(images), images[0].Width, images[0].Height)
+
+	os.MkdirAll("test_output", 0755)
+
+	// 保存原始精灵表
+	sheetPath := "test_output/sprite_sheet.png"
+	if err := os.WriteFile(sheetPath, images[0].Data, 0644); err != nil {
+		fatalf("save sheet: %v", err)
+	}
+	fmt.Printf("Saved sprite sheet → %s (%d bytes)\n", sheetPath, len(images[0].Data))
+
+	// 3. splitsprite 拆分精灵表
+	fmt.Println("\n=== Step 3: Split sprite sheet ===")
+	sheetImg, err := decodePNG(images[0].Data)
+	if err != nil {
+		fatalf("decode sheet: %v", err)
+	}
+	opts := splitsprite.DefaultOptions()
+	opts.GridRows = 4
+	opts.GridCols = 4
+	opts.GridPadding = 2
+	opts.CenterAlign = true
+	frames, err := splitsprite.Process(sheetImg, opts)
+	if err != nil {
+		fatalf("split failed: %v", err)
+	}
+	fmt.Printf("Detected %d frames\n", len(frames))
+
+	// 保存单帧
+	for i, f := range frames {
+		fn := fmt.Sprintf("test_output/frame_%03d.png", i)
+		if err := savePNG(fn, f); err != nil {
+			fatalf("save frame %d: %v", i, err)
+		}
+	}
+	fmt.Printf("Saved %d frames → test_output/frame_*.png\n", len(frames))
+
+	// 4. 生成 GIF 预览
+	fmt.Println("\n=== Step 4: Generate GIF preview ===")
+	gifPath := "test_output/preview.gif"
+	if err := genGIF(gifPath, frames, 12); err != nil {
+		fatalf("generate GIF: %v", err)
+	}
+	fmt.Printf("GIF preview → %s (%d frames)\n", gifPath, len(frames))
+
+	fmt.Println("\n=== Done ===")
+	fmt.Println("Output files:")
+	fmt.Println("  test_output/sprite_sheet.png  — original sprite sheet")
+	fmt.Println("  test_output/frame_*.png       — individual frames")
+	fmt.Println("  test_output/preview.gif       — animated GIF preview")
+}
+
+func genGIF(path string, frames []image.Image, delay int) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	pal := buildPalette(frames)
+	anim := &gif.GIF{}
+	for _, frame := range frames {
+		b := frame.Bounds()
+		paletted := image.NewPaletted(b, pal)
+		draw.Draw(paletted, b, frame, b.Min, draw.Src)
+		anim.Image = append(anim.Image, paletted)
+		anim.Delay = append(anim.Delay, delay)
+	}
+	anim.LoopCount = 0 // loop forever
+	return gif.EncodeAll(f, anim)
+}
+
+func buildPalette(frames []image.Image) color.Palette {
+	hist := make(map[color.RGBA]int)
+	sampleStep := max(1, len(frames)/8)
+	for i := 0; i < len(frames); i += sampleStep {
+		b := frames[i].Bounds()
+		step := max(1, (b.Dx()*b.Dy())/4096)
+		n := 0
+		for y := b.Min.Y; y < b.Max.Y; y++ {
+			for x := b.Min.X; x < b.Max.X; x++ {
+				if n%step != 0 {
+					n++
+					continue
+				}
+				n++
+				r, g, bl, a := frames[i].At(x, y).RGBA()
+				if a > 0 {
+					c := color.RGBA{R: uint8(r >> 8), G: uint8(g >> 8), B: uint8(bl >> 8), A: uint8(a >> 8)}
+					hist[c]++
+				}
+			}
+		}
+	}
+	pal := make(color.Palette, 0, 256)
+	for c := range hist {
+		pal = append(pal, c)
+		if len(pal) >= 240 {
+			break
+		}
+	}
+	pal = append(pal,
+		color.RGBA{0, 0, 0, 0},
+		color.RGBA{0, 0, 0, 255},
+		color.RGBA{255, 255, 255, 255},
+	)
+	return pal
+}
+
+func decodePNG(data []byte) (image.Image, error) {
+	img, _, err := image.Decode(bytes.NewReader(data))
+	if err != nil {
+		return nil, err
+	}
+	return img, nil
+}
+
+func savePNG(path string, img image.Image) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return png.Encode(f, img)
+}
+
+func fatalf(format string, args ...interface{}) {
+	fmt.Fprintf(os.Stderr, format+"\n", args...)
+	os.Exit(1)
+}