feat(字体处理): 修复符号字体缺字错字

ofdgo_pdf_font.go

@@ -143,7 +143,7 @@ func (p *pdfImporter) importedFont(source *pdfgo.Font) (*pdfImportedFont, error)
 	return result, nil
 }
 
-// symbolFont 将标准符号字体的旧式字符表转换为Unicode映射，保留原字形编号
+// symbolFont 加载标准符号字体，保留原字形编号和源字形名称
 // 入参: source 未嵌入的PDF字体
 // 返回: *pdfImportedFont 可用的符号字体，无匹配时为空, error 字体或取消错误
 func (p *pdfImporter) symbolFont(source *pdfgo.Font) (*pdfImportedFont, error) {
@@ -167,56 +167,14 @@ func (p *pdfImporter) symbolFont(source *pdfgo.Font) (*pdfImportedFont, error) {
 		p.symbolFonts[source] = nil
 		return nil, nil
 	}
-	tables, err := fontFileTables(resolved.Data, 0)
-	if err != nil || !pdfSymbolCmap(tables["cmap"]) {
+	program, names, err := symbolFontProgram(p.ctx, resolved.Data, name)
+	if err != nil {
+		return nil, err
+	}
+	if len(names) == 0 {
 		p.symbolFonts[source] = nil
 		return nil, nil
 	}
-	standard, err := p.reader.ReadFontContext(p.ctx, pdfgo.Dictionary{"Type": pdfgo.Name("Font"), "Subtype": pdfgo.Name("Type1"), "BaseFont": pdfgo.Name(name)})
-	if err != nil {
-		return nil, err
-	}
-	codes := make([]byte, 256)
-	for index := range codes {
-		codes[index] = byte(index)
-	}
-	glyphs, err := standard.DecodeContext(p.ctx, codes)
-	if err != nil {
-		return nil, err
-	}
-	original := parseCmapMappings(tables["cmap"])
-	mapping := make(map[rune]uint16)
-	names := make(map[string]uint16)
-	for _, glyph := range glyphs {
-		if glyph.Name == ".notdef" || glyph.Name == "" {
-			continue
-		}
-		id := original[rune(glyph.Code)]
-		for _, base := range [...]rune{0xf000, 0xf100, 0xf200} {
-			if candidate := original[base+rune(glyph.Code)]; candidate != 0 {
-				if id != 0 && id != candidate {
-					return nil, fmt.Errorf("ambiguous PDF symbol font mapping")
-				}
-				id = candidate
-			}
-		}
-		if id == 0 {
-			continue
-		}
-		names[glyph.Name] = id
-		if char, size := utf8.DecodeRuneInString(glyph.Text); size != 0 && size == len(glyph.Text) {
-			mapping[char] = id
-		}
-	}
-	if len(mapping) == 0 {
-		p.symbolFonts[source] = nil
-		return nil, nil
-	}
-	tables["cmap"] = buildCmapTable(0, mapping)
-	program, err := serializeOTF(tables)
-	if err != nil {
-		return nil, err
-	}
 	resource, err := p.editor.backends.FontResources.OpenFontResource(FontFile{Name: name + ".ttf", Data: program}, 0)
 	if err != nil {
 		return nil, err
@@ -234,29 +192,6 @@ func (p *pdfImporter) symbolFont(source *pdfgo.Font) (*pdfImportedFont, error) {
 	return result, nil
 }
 
-// pdfSymbolCmap 识别不含Unicode字符表的Windows符号字体
-// 入参: data 字符映射表
-// 返回: bool 是否为旧式符号字体
-func pdfSymbolCmap(data []byte) bool {
-	if len(data) < 4 {
-		return false
-	}
-	count := int(binary.BigEndian.Uint16(data[2:]))
-	if count > (len(data)-4)/8 {
-		return false
-	}
-	symbol := false
-	for i := range count {
-		pos := 4 + i*8
-		platform, encoding := binary.BigEndian.Uint16(data[pos:]), binary.BigEndian.Uint16(data[pos+2:])
-		if platform == 0 || platform == 3 && (encoding == 1 || encoding == 10) {
-			return false
-		}
-		symbol = symbol || platform == 3 && encoding == 0
-	}
-	return symbol
-}
-
 // pdfFontProgram 为PDF子集字体补齐封装表，保留字形轮廓和编号
 // 无效字符表按PDF已解码字形重建，不改变字符对应的字形编号
 // 入参: source PDF字体, type1 已解析的Type1程序，nil时按需解析