feat(转换能力): 优化色料转换采样

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/tdewolff/canvas v0.0.0-20260923214215-09804640d00c
 	github.com/tdewolff/font v0.0.0-20260913163313-54f98bb59ee6
 	github.com/xiaoqidun/jbig2 v1.1.1
-	github.com/xiaoqidun/pdfgo v0.0.0-20261008021024-e8f1cc0a7ad9
+	github.com/xiaoqidun/pdfgo v0.0.0-20261008045044-ada80114c916
 	golang.org/x/crypto v0.57.0
 	golang.org/x/image v0.46.0
 	golang.org/x/text v0.42.0

go.sum

@@ -62,8 +62,8 @@ github.com/tdewolff/test v1.0.12 h1:7F21DqIajswxuche0geHdrUZRCWE4oko4b7bcmkkrxk=
 github.com/tdewolff/test v1.0.12/go.mod h1:XPuWBzvdUzhCuxWO1ojpXsyzsA5bFoS3tO/Q3kFuTG8=
 github.com/xiaoqidun/jbig2 v1.1.1 h1:SjliS9ZO0e9HX5oYUfBuXrfFsXhWricrSz+XY4zORDI=
 github.com/xiaoqidun/jbig2 v1.1.1/go.mod h1:8QonVWtENmh2kc6l+leqeGl7psb79DWlHDkCpdChjfQ=
-github.com/xiaoqidun/pdfgo v0.0.0-20261008021024-e8f1cc0a7ad9 h1:aHEEZYzIL7cCLW9IXMlBC+LyCxkYrge3Zw/GfioDT2I=
-github.com/xiaoqidun/pdfgo v0.0.0-20261008021024-e8f1cc0a7ad9/go.mod h1:4Pf0JO0BEf1uzRY+uZjlMjN/OPn3PYa0YMi6cqPPTLQ=
+github.com/xiaoqidun/pdfgo v0.0.0-20261008045044-ada80114c916 h1:SwXbZ6zLtTCxMeV7A5GBSxgNhyVfdzWLhPh38IdkVTc=
+github.com/xiaoqidun/pdfgo v0.0.0-20261008045044-ada80114c916/go.mod h1:4Pf0JO0BEf1uzRY+uZjlMjN/OPn3PYa0YMi6cqPPTLQ=
 github.com/xyproto/randomstring v1.0.5 h1:YtlWPoRdgMu3NZtP45drfy1GKoojuR7hmRcnhZqKjWU=
 github.com/xyproto/randomstring v1.0.5/go.mod h1:rgmS5DeNXLivK7YprL0pY+lTuhNQW3iGxZ18UQApw/E=
 github.com/yuin/goldmark v1.8.5 h1:r6N5afV5qj/5S4UTch8agZHJ8UxNCMwX7WjkkJam2NA=

ofdgo_pdf_composite_draw.go

@@ -789,8 +789,12 @@ func (c *pdfCompositor) imageColor(mark *pdfgo.ImageMark, point pdfgo.Point, spa
 	if point.X < 0 || point.X > 1 || point.Y < 0 || point.Y > 1 {
 		return [4]float64{}, 0, nil
 	}
+	process, err := c.cache.imageProcess(c.importer, mark.Image, space, c.softMask)
+	if err != nil {
+		return [4]float64{}, 0, err
+	}
 	source := c.cache.images[mark.Image]
-	if source == nil {
+	if process == nil && source == nil {
 		var err error
 		source, err = mark.Image.DecodeComponentsViewContext(c.importer.ctx)
 		if err != nil {
@@ -798,22 +802,13 @@ func (c *pdfCompositor) imageColor(mark *pdfgo.ImageMark, point pdfgo.Point, spa
 		}
 		c.cache.images[mark.Image] = source
 	}
-	x, y := point.X*float64(source.Rect.Dx())-.5, (1-point.Y)*float64(source.Rect.Dy())-.5
-	key := pdfImageProcessKey{image: mark.Image, space: space, softMask: c.softMask}
-	process, prepared := c.cache.imageProcesses[key]
-	if !prepared {
-		var err error
-		process, err = source.PrepareProcess(&pdfgo.ColorantDevice{Space: space}, space, c.softMask)
-		if err != nil {
-			return [4]float64{}, 0, err
-		}
-		if c.cache.imageProcesses == nil {
-			c.cache.imageProcesses = make(map[pdfImageProcessKey]*pdfgo.ImageProcess)
-		}
-		c.cache.imageProcesses[key] = process
+	bounds := process.Bounds()
+	if process == nil {
+		bounds = source.Rect
 	}
+	x, y := point.X*float64(bounds.Dx())-.5, (1-point.Y)*float64(bounds.Dy())-.5
 	sample := func(x, y int) ([4]float64, float64) {
-		x, y = source.Rect.Min.X+max(0, min(source.Rect.Dx()-1, x)), source.Rect.Min.Y+max(0, min(source.Rect.Dy()-1, y))
+		x, y = bounds.Min.X+max(0, min(bounds.Dx()-1, x)), bounds.Min.Y+max(0, min(bounds.Dy()-1, y))
 		if process != nil {
 			return process.ValuesAt(x, y)
 		}
@@ -862,7 +857,7 @@ func (c *pdfCompositor) imageColor(mark *pdfgo.ImageMark, point pdfgo.Point, spa
 	if process != nil || space.Equal(source.Space) {
 		return values, alpha, nil
 	}
-	values, err := space.ConvertWith(values[:source.Space.Components()], source.Space, mark.Style.RenderingIntent, mark.Style.ColorConversion)
+	values, err = space.ConvertWith(values[:source.Space.Components()], source.Space, mark.Style.RenderingIntent, mark.Style.ColorConversion)
 	return values, alpha, err
 }
 

ofdgo_pdf_composite_pattern.go

@@ -246,9 +246,13 @@ func (p *pdfImporter) directCompositeNode(node pdfCompositeNode, space *pdfgo.Co
 		}
 		if space.Model == "DeviceCMYK" && style.ColorConversion != (pdfgo.ColorConversion{}) {
 			if node.image != nil && !node.image.Image.ImageMask {
+				_, native, err := pdfImageProcessColorants(node.image.Image)
+				if err != nil {
+					return false, err
+				}
+				if !native {
 					source := p.compositingCache().images[node.image.Image]
 					if source == nil {
-					var err error
 						source, err = node.image.Image.DecodeComponentsViewContext(p.ctx)
 						if err != nil {
 							return false, err
@@ -258,6 +262,7 @@ func (p *pdfImporter) directCompositeNode(node pdfCompositeNode, space *pdfgo.Co
 					if source.Space.Model == "DeviceRGB" && source.Space.Device() {
 						return false, nil
 					}
+				}
 			} else {
 				for i, paint := range [2]pdfgo.Paint{style.Fill, style.Stroke} {
 					if i == 0 && !fill || i == 1 && !stroke || paint.None || paint.Tiling != nil {

ofdgo_pdf_image_native.go

@@ -53,17 +53,8 @@ func (p *pdfImporter) imageProcessModel(source *pdfgo.Image) (pdfgo.Name, error)
 // 返回: image.Image 只读图像, error 解码或分量映射错误
 func (p *pdfImporter) imageProcess(source *pdfgo.Image, model pdfgo.Name) (image.Image, error) {
 	cache := p.compositingCache()
-	components := cache.images[source]
-	if components == nil {
-		var err error
-		components, err = source.DecodeComponentsViewContext(p.ctx)
-		if err != nil {
-			return nil, err
-		}
-		cache.images[source] = components
-	}
 	space := &pdfgo.ColorSpace{Model: model}
-	process, err := components.PrepareProcess(&pdfgo.ColorantDevice{Space: space}, space, false)
+	process, err := cache.imageProcess(p, source, space, false)
 	if err != nil {
 		return nil, err
 	}
@@ -73,6 +64,32 @@ func (p *pdfImporter) imageProcess(source *pdfgo.Image, model pdfgo.Name) (image
 	return &pdfNativeImage{source: process, space: space}, nil
 }
 
+// imageProcess 复用同组原生采样，仅在需要备用颜色时保留完整分量
+// 入参: importer 导入器, source 源图像, space 组混合空间, softMask 是否用于软蒙版
+// 返回: *pdfgo.ImageProcess 原生采样，需要备用色时为nil, error 解码或布局错误
+func (c *pdfCompositeCache) imageProcess(importer *pdfImporter, source *pdfgo.Image, space *pdfgo.ColorSpace, softMask bool) (*pdfgo.ImageProcess, error) {
+	key := pdfImageProcessKey{image: source, space: space, softMask: softMask}
+	if process, found := c.imageProcesses[key]; found {
+		return process, nil
+	}
+	device := &pdfgo.ColorantDevice{Space: space}
+	var process *pdfgo.ImageProcess
+	var err error
+	if components := c.images[source]; components != nil {
+		process, err = components.PrepareProcess(device, space, softMask)
+	} else {
+		process, err = source.DecodeProcessContext(importer.ctx, device, space, softMask)
+	}
+	if err != nil {
+		return nil, err
+	}
+	if c.imageProcesses == nil {
+		c.imageProcesses = make(map[pdfImageProcessKey]*pdfgo.ImageProcess)
+	}
+	c.imageProcesses[key] = process
+	return process, nil
+}
+
 // ColorModel 保留16位原生分量与源透明度
 // 返回: color.Model 非预乘颜色模型
 func (s *pdfNativeImage) ColorModel() color.Model { return color.NRGBA64Model }