feat(后端架构): 移除实验性GoGPU后端，保留多后端扩展能力

ofdgo_render_cache.go

@@ -16,9 +16,6 @@ package ofdgo
 
 import (
 	"container/list"
-	"crypto/sha256"
-	"encoding/binary"
-	"math"
 )
 
 // renderCache 按估算字节数限制派生渲染数据，淘汰不修改源资源
@@ -85,70 +82,3 @@ func rasterCommandCost(command RasterCommand) int {
 	}
 	return cost
 }
-
-// rasterCommandKey 按完整路径、样式、裁剪及像素配置标识非图片指令
-// 入参: page 页面尺寸和DPI, command 绘制指令
-// 返回: [32]byte 内容键
-func rasterCommandKey(page *RasterPage, command RasterCommand) [32]byte {
-	h := sha256.New()
-	path, clip := rasterClipKey(page, command.Path), rasterClipKey(page, command.Clip)
-	h.Write(path[:])
-	h.Write(clip[:])
-	var data [8]byte
-	number := func(value float64) {
-		binary.LittleEndian.PutUint64(data[:], math.Float64bits(value))
-		h.Write(data[:])
-	}
-	flag := func(value bool) {
-		if value {
-			h.Write([]byte{1})
-		} else {
-			h.Write([]byte{0})
-		}
-	}
-	word := func(value string) {
-		number(float64(len(value)))
-		h.Write([]byte(value))
-	}
-	flag(command.Clip != nil)
-	flag(command.EvenOdd)
-	for _, value := range command.Transform {
-		number(value)
-	}
-	c := command.Paint.Color
-	h.Write([]byte{c.R, c.G, c.B, c.A})
-	flag(command.Stroke != nil)
-	if stroke := command.Stroke; stroke != nil {
-		number(stroke.Width)
-		number(stroke.MiterLimit)
-		number(stroke.Tolerance)
-		number(stroke.DashOffset)
-		word(stroke.Cap)
-		word(stroke.Join)
-		number(float64(len(stroke.Dashes)))
-		for _, dash := range stroke.Dashes {
-			number(dash)
-		}
-	}
-	flag(command.Paint.Gradient != nil)
-	if g := command.Paint.Gradient; g != nil {
-		h.Write([]byte{byte(g.Kind)})
-		for _, value := range []float64{g.Start.X, g.Start.Y, g.End.X, g.End.Y, g.R0, g.R1} {
-			number(value)
-		}
-		flag(g.Spread != nil)
-		if spread := g.Spread; spread != nil {
-			number(float64(spread.Extend))
-			number(spread.Period)
-			word(spread.MapType)
-		}
-		for _, stop := range g.Stops {
-			number(stop.Offset)
-			c := stop.Color
-			h.Write([]byte{c.R, c.G, c.B, c.A})
-		}
-	}
-	var key [32]byte
-	copy(key[:], h.Sum(nil))
-	return key
-}