feat(转换能力): 完善渐变转换与图像复用

go.mod

@@ -9,7 +9,7 @@ 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 v0.0.0-20260928085418-08275755d188
+	github.com/xiaoqidun/pdfgo v0.0.0-20260928094736-cdc5f892445c
 	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 v0.0.0-20260928085418-08275755d188 h1:XMOU0kQii0LW3BcFxPQLA7tgVfDmZ6zQcpZuU+eP+fk=
+github.com/xiaoqidun/pdfgo v0.0.0-20260928094736-cdc5f892445c h1:6idDj210CT1eyGK/fHDw0hD90GSrLqeRV7ECaP9dfyI=
-github.com/xiaoqidun/pdfgo v0.0.0-20260928085418-08275755d188/go.mod h1:4Pf0JO0BEf1uzRY+uZjlMjN/OPn3PYa0YMi6cqPPTLQ=
+github.com/xiaoqidun/pdfgo v0.0.0-20260928094736-cdc5f892445c/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.go

@@ -75,7 +75,7 @@ type pdfImporter struct {
 	objects         []GraphicObject
 	pages           map[pdfgo.Reference]*pdfgo.Page
 	pageIDs         map[pdfgo.Reference]string
-	imageIDs        map[*pdfgo.Stream]string
+	imageIDs        map[pdfImageKey]string
 	maskClips       map[*pdfgo.SoftMask]pdfgo.Path
 	pageBox         pdfgo.Rectangle
 	pageWidth       float64

ofdgo_pdf_composite_draw.go

@@ -390,7 +390,10 @@ func (c *pdfCompositor) mask(mask *pdfgo.SoftMask, inherited *pdfgo.ColorSpace)
 				return nil, err
 			}
 		}
-		result[i] = mask.Transfer(v)
+		result[i], err = mask.Transfer(v)
+		if err != nil {
+			return nil, err
+		}
 	}
 	c.masks[mask] = result
 	return result, nil

ofdgo_pdf_group.go

@@ -522,7 +522,10 @@ func (p *pdfImporter) maskClip(mask *pdfgo.SoftMask) (pdfgo.Path, error) {
 		return pdfgo.Path{}, err
 	}
 	opacity := func(v float64) (bool, error) {
-		v = mask.Transfer(v)
+		v, err := mask.Transfer(v)
+		if err != nil {
+			return false, err
+		}
 		if v != 0 && v != 1 {
 			return false, &pdfgo.UnsupportedError{Feature: "nonbinary luminosity mask"}
 		}

ofdgo_pdf_object.go

@@ -32,6 +32,12 @@ import (
 	"github.com/xiaoqidun/pdfgo"
 )
 
+// pdfImageKey 区分同一图像流在不同渲染意图下的资源
+type pdfImageKey struct {
+	stream *pdfgo.Stream
+	intent pdfgo.Name
+}
+
 // image 转换图像样本，不将整页或其他对象栅格化
 // 入参: mark PDF图像绘制信息
 // 返回: error 错误信息
@@ -59,7 +65,8 @@ func (p *pdfImporter) image(mark pdfgo.ImageMark) error {
 		return &pdfgo.UnsupportedError{Feature: "image color separation overprint"}
 	}
 	source := mark.Image
-	id := p.imageIDs[source.Stream]
+	key := pdfImageKey{stream: source.Stream, intent: source.Intent}
+	id := p.imageIDs[key]
 	if source.ImageMask {
 		id = ""
 	}
@@ -125,9 +132,9 @@ func (p *pdfImporter) image(mark pdfgo.ImageMark) error {
 		}
 		if !source.ImageMask {
 			if p.imageIDs == nil {
-				p.imageIDs = map[*pdfgo.Stream]string{}
+				p.imageIDs = map[pdfImageKey]string{}
 			}
-			p.imageIDs[source.Stream] = id
+			p.imageIDs[key] = id
 		}
 	}
 	return p.appendImage(mark, id)