fix(回归优化): 修复浏览器回归并优化内存

assets/webui/ofdgo.js

@@ -7687,13 +7687,18 @@ function chooseResourceFile(action) {
 async function changeManagedResource(action, item, file) {
 	if (!item || !state.editing) return;
 	releaseResourcePreview();
+	const page = Number(resourceElements.Page.value), object = resourceElements.Object.value;
 	const format = file?.name.includes(".") ? file.name.split(".").at(-1).toUpperCase() : "";
 	const changed = item.kind === "Attachment" && action !== "bind" && action !== "unbind"
 		? await changeDocument("ofdgoChangeAttachment", null, action, item.id, file ? [file.name] : [], file ? [file] : [])
-		: await changeDocument("ofdgoChangeResource", null, action, item.kind, item.id, format, file || null, Number(resourceElements.Page.value), resourceElements.Object.value);
+		: await changeDocument("ofdgoChangeResource", null, action, item.kind, item.id, format, file || null, page, object);
 	if (changed) {
 		await loadManagedResources();
-		if (action === "bind" || action === "unbind") resourceElements.Status.textContent = action === "bind" ? "已绑定" : "已解绑";
+		if (action === "bind" || action === "unbind") {
+			resourceElements.Page.value = String(page);
+			await loadResourceTargets(object);
+			resourceElements.Status.textContent = action === "bind" ? "已绑定" : "已解绑";
+		}
 	}
 }
 

internal/base/font/sfnt.go

@@ -17,9 +17,11 @@ package font
 import (
 	"encoding/binary"
 	"fmt"
+	"iter"
 	"maps"
 	"slices"
 	"sync"
+	"unicode/utf8"
 
 	"github.com/go-text/typesetting/font/opentype/tables"
 )
@@ -34,10 +36,12 @@ type SFNT struct {
 	reverse                            map[uint16][]rune
 }
 
-// sfntCmap 保存编码记录及对应字符映射，标记已解析的共享子表
+// sfntCmap 保存编码记录及字符映射，连续区间与共享子表不重复展开
 type sfntCmap struct {
 	platform, encoding, format uint16
 	mapping                    map[rune]uint16
+	groups                     []byte
+	entries                    uint64
 	duplicate                  bool
 }
 
@@ -90,7 +94,7 @@ func ParseSFNTTables(table map[string][]byte) (*SFNT, error) {
 		if cmap.duplicate {
 			continue
 		}
-		for _, glyph := range cmap.mapping {
+		for _, glyph := range cmap.pairs() {
 			if glyph >= f.count {
 				return nil, fmt.Errorf("cmap glyph index out of range")
 			}
@@ -119,7 +123,7 @@ func readSFNTCmaps(data []byte) ([]sfntCmap, error) {
 	}
 	count := int(binary.BigEndian.Uint16(data[2:]))
 	result := make([]sfntCmap, 0, count)
-	parsed := make(map[uint32]map[rune]uint16)
+	parsed := make(map[uint32]sfntCmap)
 	for i := range count {
 		record := data[4+8*i:]
 		offset := binary.BigEndian.Uint32(record[4:])
@@ -128,23 +132,44 @@ func readSFNTCmaps(data []byte) ([]sfntCmap, error) {
 		}
 		sub := data[offset:]
 		format := binary.BigEndian.Uint16(sub)
-		mapping, found := parsed[offset]
+		cmap, found := parsed[offset]
 		if !found {
-			mapping = make(map[rune]uint16)
+			cmap.mapping = make(map[rune]uint16)
 			var err error
 			switch format {
 			case 0:
-				parseCmapFormat0(sub, mapping)
+				parseCmapFormat0(sub, cmap.mapping)
 			case 4:
-				parseCmapFormat4(sub, mapping)
+				parseCmapFormat4(sub, cmap.mapping)
 			case 6:
-				parseCmapFormat6(sub, mapping)
+				parseCmapFormat6(sub, cmap.mapping)
 			case 12:
-				parseCmapFormat12(sub, mapping)
+				if len(sub) >= 16 {
+					length := uint64(binary.BigEndian.Uint32(sub[4:]))
+					count := uint64(binary.BigEndian.Uint32(sub[12:]))
+					if length >= 16 && length <= uint64(len(sub)) && count <= (length-16)/12 {
+						cmap.groups = sub[16 : 16+12*count]
+						for offset := 0; offset < len(cmap.groups); offset += 12 {
+							first := binary.BigEndian.Uint32(cmap.groups[offset:])
+							last := binary.BigEndian.Uint32(cmap.groups[offset+4:])
+							if first > last || offset != 0 && first <= binary.BigEndian.Uint32(cmap.groups[offset-8:]) {
+								cmap.groups = nil
+								parseCmapFormat12(sub, cmap.mapping)
+								break
+							}
+						}
+						if cmap.groups != nil {
+							cmap.mapping = nil
+							for range cmap.pairs() {
+								cmap.entries++
+							}
+						}
+					}
+				}
 			case 2:
-				mapping, err = parseCmapFormat2(sub)
+				cmap.mapping, err = parseCmapFormat2(sub)
 			case 8, 10, 13:
-				mapping, err = parseCmapExtended(sub)
+				cmap.mapping, err = parseCmapExtended(sub)
 			case 14:
 			default:
 				return nil, fmt.Errorf("unsupported cmap format %d", format)
@@ -152,13 +177,67 @@ func readSFNTCmaps(data []byte) ([]sfntCmap, error) {
 			if err != nil {
 				return nil, err
 			}
-			parsed[offset] = mapping
+			parsed[offset] = cmap
 		}
-		result = append(result, sfntCmap{platform: binary.BigEndian.Uint16(record), encoding: binary.BigEndian.Uint16(record[2:]), format: format, mapping: mapping, duplicate: found})
+		cmap.platform, cmap.encoding, cmap.format, cmap.duplicate = binary.BigEndian.Uint16(record), binary.BigEndian.Uint16(record[2:]), format, found
+		result = append(result, cmap)
 	}
 	return result, nil
 }
 
+// pairs 按原映射返回字符与字形，连续编码段不展开存储
+// 返回: iter.Seq2[rune, uint16] 非零有效字符映射
+func (c sfntCmap) pairs() iter.Seq2[rune, uint16] {
+	return func(yield func(rune, uint16) bool) {
+		for char, glyph := range c.mapping {
+			if !yield(char, glyph) {
+				return
+			}
+		}
+		for offset := 0; offset+12 <= len(c.groups); offset += 12 {
+			group := c.groups[offset:]
+			first, last, glyph := binary.BigEndian.Uint32(group), binary.BigEndian.Uint32(group[4:]), binary.BigEndian.Uint32(group[8:])
+			if first > last || first > utf8.MaxRune || glyph > 65535 {
+				continue
+			}
+			end := min(uint64(last), uint64(first)+65535-uint64(glyph), uint64(utf8.MaxRune))
+			for char := uint64(first); char <= end; char++ {
+				id := uint16(uint64(glyph) + char - uint64(first))
+				if id != 0 && utf8.ValidRune(rune(char)) && !yield(rune(char), id) {
+					return
+				}
+			}
+		}
+	}
+}
+
+// lookup 查找原字符映射，连续编码段使用有序区间查询
+// 入参: char 字符
+// 返回: uint16 字形编号, bool 是否存在映射
+func (c sfntCmap) lookup(char rune) (uint16, bool) {
+	if glyph, ok := c.mapping[char]; ok {
+		return glyph, true
+	}
+	if !utf8.ValidRune(char) {
+		return 0, false
+	}
+	low, high := 0, len(c.groups)/12
+	for low < high {
+		middle := low + (high-low)/2
+		group := c.groups[middle*12:]
+		first, last := binary.BigEndian.Uint32(group), binary.BigEndian.Uint32(group[4:])
+		if uint32(char) < first {
+			high = middle
+		} else if uint32(char) > last {
+			low = middle + 1
+		} else {
+			glyph := uint64(binary.BigEndian.Uint32(group[8:])) + uint64(uint32(char)-first)
+			return uint16(glyph), glyph > 0 && glyph <= 65535
+		}
+	}
+	return 0, false
+}
+
 // UnitsPerEm 返回字体设计单位
 // 返回: uint16 每em单位数
 func (f *SFNT) UnitsPerEm() uint16 { return f.units }
@@ -172,7 +251,7 @@ func (f *SFNT) NumGlyphs() uint16 { return f.count }
 func (f *SFNT) CmapEntries() uint64 {
 	var count uint64
 	for _, cmap := range f.cmaps {
-		count += uint64(len(cmap.mapping))
+		count += uint64(len(cmap.mapping)) + cmap.entries
 	}
 	return count
 }
@@ -185,14 +264,14 @@ func (f *SFNT) GlyphIndex(char rune) uint16 {
 		if cmap.duplicate {
 			continue
 		}
-		if gid := cmap.mapping[char]; gid != 0 {
+		if gid, ok := cmap.lookup(char); ok && gid != 0 {
 			return gid
 		}
 	}
 	return 0
 }
 
-// glyphCharacters 返回指向指定字形的全部字符
+// glyphCharacters 返回指向指定字形的全部字符，连续区间按需反查
 // 入参: gid 字形编号
 // 返回: []rune 排序后的字符
 func (f *SFNT) glyphCharacters(gid uint16) []rune {
@@ -204,7 +283,7 @@ func (f *SFNT) glyphCharacters(gid uint16) []rune {
 				continue
 			}
 			for char, glyph := range cmap.mapping {
-				if glyph != 0 && !seen[char] {
+				if glyph != 0 && !seen[char] && f.GlyphIndex(char) == glyph {
 					f.reverse[glyph] = append(f.reverse[glyph], char)
 					seen[char] = true
 				}
@@ -214,7 +293,28 @@ func (f *SFNT) glyphCharacters(gid uint16) []rune {
 			slices.Sort(chars)
 		}
 	})
-	return f.reverse[gid]
+	if gid == 0 {
+		return nil
+	}
+	chars := slices.Clone(f.reverse[gid])
+	for _, cmap := range f.cmaps {
+		if cmap.duplicate {
+			continue
+		}
+		for offset := 0; offset+12 <= len(cmap.groups); offset += 12 {
+			group := cmap.groups[offset:]
+			first, last, glyph := binary.BigEndian.Uint32(group), binary.BigEndian.Uint32(group[4:]), binary.BigEndian.Uint32(group[8:])
+			if first > last || uint32(gid) < glyph {
+				continue
+			}
+			char := uint64(first) + uint64(uint32(gid)-glyph)
+			if char <= uint64(last) && char <= utf8.MaxRune && utf8.ValidRune(rune(char)) && f.GlyphIndex(rune(char)) == gid {
+				chars = append(chars, rune(char))
+			}
+		}
+	}
+	slices.Sort(chars)
+	return slices.Compact(chars)
 }
 
 // GlyphAdvance 返回水平字宽

internal/base/font/subset.go

@@ -197,7 +197,7 @@ func subsetSourceSFNT(sfnt *SFNT, usage *Usage, size int) []byte {
 	for char := range usage.Characters {
 		id := sfnt.GlyphIndex(char)
 		for _, cmap := range unicodeTables {
-			if alternate, ok := cmap.mapping[char]; ok && alternate != id {
+			if alternate, ok := cmap.lookup(char); ok && alternate != id {
 				return nil
 			}
 		}

ofdgo_editor_font.go

@@ -291,6 +291,132 @@ func editorObjectFontScan(object GraphicObject) bool {
 // 入参: progress 保存进度回调
 // 返回: map[string][]byte 包内字体子集, error 错误信息
 func (e *Editor) subsetFonts(progress editorProgress) (map[string][]byte, error) {
+	result, err := e.subsetNewFonts(progress)
+	if err != nil {
+		return nil, err
+	}
+	ctx := context.Background()
+	if e.output != nil {
+		ctx = e.output.ctx
+	}
+	source, err := e.subsetSnapshotFonts(ctx, progress.withContext(ctx))
+	if err != nil {
+		return nil, err
+	}
+	if result == nil {
+		return source, nil
+	}
+	maps.Copy(result, source)
+	return result, nil
+}
+
+// subsetSnapshotFonts 在写出时扫描快照中新增字体的完整包引用，不改动既有字体
+// 入参: ctx 取消上下文, progress 写出进度
+// 返回: map[string][]byte 新增字体的安全子集, error 扫描或裁剪错误
+func (e *Editor) subsetSnapshotFonts(ctx context.Context, progress editorProgress) (map[string][]byte, error) {
+	if e.source == nil || e.backends.FontResources == nil {
+		return nil, ctx.Err()
+	}
+	candidates := make(map[string]bool)
+	for _, resource := range e.resources {
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+		if resource.font != nil && resource.font.FontFile != "" && e.source.reader.fileNames[resource.name] {
+			candidates[resource.name] = true
+		}
+	}
+	if len(candidates) == 0 {
+		return nil, ctx.Err()
+	}
+	view, err := e.readerContext(ctx, progress)
+	if err != nil {
+		return nil, err
+	}
+	defer view.Close()
+	refs, resources, references, safe, err := scanEditorResources(ctx, view, view.files, nil, maps.Clone(view.fileNames), progress, true)
+	if err != nil || !safe {
+		return nil, err
+	}
+	scoped, err := resourceReferenceScopes(ctx, refs.documents, resources, references, "")
+	if err != nil || scoped == nil {
+		return nil, err
+	}
+	read := func(name string) ([]byte, error) { return view.readFileViewContext(ctx, name) }
+	usage, err := resourceFontUsage(ctx, resources, scoped, read)
+	if err != nil {
+		return nil, err
+	}
+	for _, source := range references {
+		for name := range source.files {
+			if font := usage[name]; font != nil && !source.versions[name] {
+				font.unsafe = true
+			}
+		}
+		for _, definition := range source.definitions {
+			for name := range definition.files {
+				if font := usage[name]; font != nil {
+					font.unsafe = true
+				}
+			}
+		}
+	}
+	result := make(map[string][]byte)
+	for i, name := range slices.Sorted(maps.Keys(candidates)) {
+		if err := progress.report("fonts", i, len(candidates)); err != nil {
+			return nil, err
+		}
+		font := usage[name]
+		if font == nil || font.unsafe || len(font.chars)+len(font.glyphs) == 0 {
+			continue
+		}
+		data, err := read(name)
+		if err != nil {
+			return nil, err
+		}
+		parsed, err := e.backends.FontResources.OpenFontResource(FontFile{Data: data}, 0)
+		if err != nil {
+			return nil, err
+		}
+		if !parsed.CanSubset {
+			continue
+		}
+		preserve := len(font.glyphs) != 0
+		glyphs := maps.Clone(font.glyphs)
+		for char := range font.chars {
+			if err := ctx.Err(); err != nil {
+				return nil, err
+			}
+			glyphs[parsed.GlyphIndex(char)] = true
+		}
+		glyphs[0] = true
+		for id := range glyphs {
+			if id >= parsed.NumGlyphs() {
+				font.unsafe = true
+				break
+			}
+		}
+		if font.unsafe {
+			continue
+		}
+		subset, err := e.backends.FontResources.SubsetFont(data, slices.Sorted(maps.Keys(glyphs)), preserve)
+		if err != nil {
+			return nil, err
+		}
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+		if len(subset) != 0 && len(subset) < len(data) {
+			result[name] = subset
+		}
+	}
+	return result, progress.report("fonts", len(candidates), len(candidates))
+}
+
+// subsetNewFonts 解析尚未物化为源资源的新增字体，保持编辑字体完整
+// 入参: progress 写出进度
+// 返回: map[string][]byte 包内字体子集, error 读取或裁剪错误
+func (e *Editor) subsetNewFonts(progress editorProgress) (map[string][]byte, error) {
 	ctx := context.Background()
 	if e.output != nil {
 		ctx = e.output.ctx
@@ -303,7 +429,7 @@ func (e *Editor) subsetFonts(progress editorProgress) (map[string][]byte, error)
 		return nil, err
 	}
 	if !slices.ContainsFunc(e.resources, func(resource editorResource) bool {
-		return resource.font != nil && resource.font.FontFile != ""
+		return resource.font != nil && resource.font.FontFile != "" && (e.source == nil || !e.source.reader.fileNames[resource.name])
 	}) {
 		return nil, nil
 	}
@@ -318,7 +444,7 @@ func (e *Editor) subsetFonts(progress editorProgress) (map[string][]byte, error)
 		if err := progress.report("fonts", i, total); err != nil {
 			return nil, err
 		}
-		if resource.font.FontFile == "" {
+		if resource.font.FontFile == "" || e.source != nil && e.source.reader.fileNames[resource.name] {
 			continue
 		}
 		resourceFont := e.fonts[resource.font.ID]

ofdgo_pdf.go

@@ -82,6 +82,7 @@ type pdfImporter struct {
 	pageActionPage     int
 	fontIDs            map[*pdfgo.Font]string
 	fonts              map[*pdfgo.Font]*pdfImportedFont
+	fontPrograms       map[pdfFontProgramKey]*pdfImportedFont
 	symbolFonts        map[*pdfgo.Font]*pdfImportedFont
 	fontWarnings       map[string]bool
 	clipTexts          map[*pdfgo.TextClip][]TextObject

ofdgo_pdf_group.go

@@ -398,10 +398,13 @@ func (p *pdfImporter) compileGroup(build func(*pdfImporter) error) (*RasterPage,
 	if p.symbolFonts == nil {
 		p.symbolFonts = make(map[*pdfgo.Font]*pdfImportedFont)
 	}
+	if p.fontPrograms == nil {
+		p.fontPrograms = make(map[pdfFontProgramKey]*pdfImportedFont)
+	}
 	if p.clipPaths == nil {
 		p.clipPaths = resourceCache[[32]byte, pdfClipPath](p.resources, 8<<20)
 	}
-	local := pdfImporter{resources: p.resources, ctx: p.ctx, reader: p.reader, editor: editor, renderer: p.renderer, matrix: p.matrix, pageBox: p.pageBox, pageWidth: p.pageWidth, pageHeight: p.pageHeight, rasterDPI: p.rasterDPI, warning: p.warning, rasterWarned: true, fontIDs: map[*pdfgo.Font]string{}, fonts: p.fonts, symbolFonts: p.symbolFonts, clipPaths: p.clipPaths, textOrigins: p.textOrigins}
+	local := pdfImporter{resources: p.resources, ctx: p.ctx, reader: p.reader, editor: editor, renderer: p.renderer, matrix: p.matrix, pageBox: p.pageBox, pageWidth: p.pageWidth, pageHeight: p.pageHeight, rasterDPI: p.rasterDPI, warning: p.warning, rasterWarned: true, fontIDs: map[*pdfgo.Font]string{}, fonts: p.fonts, fontPrograms: p.fontPrograms, symbolFonts: p.symbolFonts, clipPaths: p.clipPaths, textOrigins: p.textOrigins}
 	if err := build(&local); err != nil {
 		return nil, box, err
 	}

ofdgo_pdf_text.go

@@ -38,6 +38,12 @@ type pdfImportedFont struct {
 	repairLimit uint16
 }
 
+// pdfFontProgramKey 区分字体封装内容及交给资源后端的来源名称
+type pdfFontProgramKey struct {
+	checksum [32]byte
+	name     string
+}
+
 // pdfTextReplacement 记录一个完整替换区段的文字数量与转换状态
 type pdfTextReplacement struct {
 	text     *pdfgo.ReplacementText
@@ -661,13 +667,17 @@ func (p *pdfImporter) importedFont(source *pdfgo.Font) (*pdfImportedFont, error)
 	if p.editor.backends.FontResources == nil {
 		return nil, fmt.Errorf("PDF font %s resource: font resources: %w", source.Name, ErrBackendUnavailable)
 	}
+	if p.editor.backends.Fonts == nil {
+		return nil, fmt.Errorf("PDF font backend unavailable")
+	}
+	key := pdfFontProgramKey{checksum: sha256.Sum256(program), name: source.Name}
+	if cached := p.fontPrograms[key]; cached != nil {
+		result.resource, result.metrics, result.checksum = cached.resource, cached.metrics, cached.checksum
+	} else {
 		result.resource, err = p.editor.backends.FontResources.OpenFontResource(FontFile{Name: source.Name + ".ttf", Data: program}, 0)
 		if err != nil {
 			return nil, fmt.Errorf("PDF font %s resource: %w", source.Name, err)
 		}
-	if p.editor.backends.Fonts == nil {
-		return nil, fmt.Errorf("PDF font backend unavailable")
-	}
 		result.metrics, err = p.editor.backends.Fonts.OpenFont(result.resource.Data)
 		if err != nil {
 			return nil, fmt.Errorf("PDF font %s metrics: %w", source.Name, err)
@@ -675,7 +685,9 @@ func (p *pdfImporter) importedFont(source *pdfgo.Font) (*pdfImportedFont, error)
 		if _, ok := result.metrics.(FontOutlines); !ok {
 			return nil, fmt.Errorf("PDF font backend does not provide glyph outlines")
 		}
-	result.checksum, result.repairLimit = sha256.Sum256(result.resource.Data), repair.MetricsLimit
+		result.checksum = sha256.Sum256(result.resource.Data)
+	}
+	result.repairLimit = repair.MetricsLimit
 	if source.Recovered || programRecovered {
 		if err := p.preservePDFObject(p.ctx, "Font", source.Dictionary); err != nil {
 			return nil, err
@@ -690,6 +702,13 @@ func (p *pdfImporter) importedFont(source *pdfgo.Font) (*pdfImportedFont, error)
 	if p.fonts == nil {
 		p.fonts = make(map[*pdfgo.Font]*pdfImportedFont)
 	}
+	if err := p.ctx.Err(); err != nil {
+		return nil, err
+	}
+	if p.fontPrograms == nil {
+		p.fontPrograms = make(map[pdfFontProgramKey]*pdfImportedFont)
+	}
+	p.fontPrograms[key] = result
 	p.fonts[source] = result
 	return result, nil
 }

ofdgo_renderer_canvas.go

@@ -19,6 +19,7 @@ import (
 	"image"
 	"image/color"
 	"image/draw"
+	"math"
 	"slices"
 
 	"github.com/tdewolff/canvas"
@@ -120,7 +121,7 @@ func (b CanvasBackend) renderImage(page *RasterPage, img *image.RGBA) (image.Ima
 			}
 			continue
 		}
-		p, err := rasterCanvasPath(cmd.Path, pathData)
+		p, err := rasterCanvasPath(visibleRasterPath(cmd, page), pathData)
 		if err != nil {
 			return nil, fmt.Errorf("canvas command %d: %w", i, err)
 		}
@@ -228,6 +229,54 @@ func (b CanvasBackend) renderImage(page *RasterPage, img *image.RGBA) (image.Ima
 	return img, nil
 }
 
+// visibleRasterPath 排除填充区域外的完整子路径，保留曲线控制范围与抗锯齿边缘
+// 入参: command 绘制指令, page 目标页面
+// 返回: []RasterSegment 可见子路径，描边和短路径沿用原数据
+func visibleRasterPath(command RasterCommand, page *RasterPage) []RasterSegment {
+	if command.Stroke != nil || len(command.Path) < 256 || command.Path[0].Verb != RasterMove {
+		return command.Path
+	}
+	padding := 25.4 / page.DPI
+	var visible []RasterSegment
+	filtered := false
+	start := 0
+	minX, minY, maxX, maxY := math.Inf(1), math.Inf(1), math.Inf(-1), math.Inf(-1)
+	flush := func(end int) {
+		if minX <= page.Width+padding && maxX >= -padding && minY <= page.Height+padding && maxY >= -padding {
+			if filtered {
+				visible = append(visible, command.Path[start:end]...)
+			}
+		} else if !filtered {
+			filtered = true
+			visible = append(visible, command.Path[:start]...)
+		}
+	}
+	include := func(point RasterPoint) bool {
+		point = command.Transform.Apply(point)
+		if !finite(point.X) || !finite(point.Y) {
+			return false
+		}
+		minX, minY = math.Min(minX, point.X), math.Min(minY, point.Y)
+		maxX, maxY = math.Max(maxX, point.X), math.Max(maxY, point.Y)
+		return true
+	}
+	for index, segment := range command.Path {
+		if segment.Verb == RasterMove && index != start {
+			flush(index)
+			start = index
+			minX, minY, maxX, maxY = math.Inf(1), math.Inf(1), math.Inf(-1), math.Inf(-1)
+		}
+		if segment.Verb > RasterClose || segment.Verb != RasterClose && !include(segment.End) || (segment.Verb == RasterQuad || segment.Verb == RasterCubic) && !include(segment.Control1) || segment.Verb == RasterCubic && !include(segment.Control2) {
+			return command.Path
+		}
+	}
+	flush(len(command.Path))
+	if !filtered {
+		return command.Path
+	}
+	return visible
+}
+
 // rasterCanvasPath 预留路径容量，保留光栅指令的构建及闭合规则
 // 入参: path 只读光栅路径, buffer 可复用的独占路径缓冲
 // 返回: *canvas.Path 使用独占缓冲的绘制路径, error 不支持的指令

ofdgo_renderer_clip_canvas.go

@@ -27,6 +27,7 @@ import (
 type clipRenderer struct {
 	path   *canvas.Path
 	clip   *canvas.Path
+	unions *renderCache[[32]byte, *canvas.Path]
 }
 
 // Size 返回不限定边界的裁剪画布尺寸
@@ -57,13 +58,23 @@ func (r *clipRenderer) RenderText(text *canvas.Text, m canvas.Matrix) {
 // 入参: img 图像, m 变换矩阵
 func (r *clipRenderer) RenderImage(img image.Image, m canvas.Matrix) {}
 
-// add 合并裁剪轮廓
+// add 合并裁剪轮廓，按完整输入复用已有并集
 // 入参: path 裁剪路径
 func (r *clipRenderer) add(path *canvas.Path) {
 	if r.path == nil {
 		r.path = path
+	} else if r.unions == nil || path == nil {
+		r.path = unionClipPath(r.path, path)
+	} else {
+		key := canvasGeometryDigest(r.path, path)
+		if merged, ok := r.unions.get(key); ok {
+			r.path = merged.Copy()
 		} else {
 			r.path = unionClipPath(r.path, path)
+			if cost := len(r.path.Data())*8 + 256; cost <= r.unions.limit {
+				r.unions.put(key, r.path.Copy(), cost)
+			}
+		}
 	}
 }
 
@@ -96,7 +107,7 @@ func (r *Renderer) buildClipPath(clips *Clips, pageH float64, bx, by float64, ma
 	}
 	var p *canvas.Path
 	for _, clip := range clips.Clip {
-		renderer := &clipRenderer{}
+		renderer := &clipRenderer{unions: r.canvasClipUnions()}
 		for _, area := range clip.Area {
 			areaCTM := matrix.Multiply(NewMatrix(area.CTM))
 			for _, pathObj := range area.Path {

ofdgo_renderer_geom_canvas.go

@@ -556,6 +556,14 @@ func clipLinearFillGeometry(path, clip GeometryPath) (GeometryPath, bool, error)
 	return *geometryFromCanvasPath(result), true, nil
 }
 
+// invertCanvasMatrix 对有限可逆矩阵求逆，保留非零小尺度变换
+// 入参: matrix 画布仿射矩阵
+// 返回: canvas.Matrix 逆矩阵, bool 是否存在有限逆矩阵
+func invertCanvasMatrix(matrix canvas.Matrix) (canvas.Matrix, bool) {
+	inverse, ok := MatrixFromValues([6]float64{matrix[0][0], matrix[1][0], matrix[0][1], matrix[1][1], matrix[0][2], matrix[1][2]}).Invert()
+	return canvas.Matrix{{inverse.a, inverse.c, inverse.e}, {inverse.b, inverse.d, inverse.f}}, ok
+}
+
 // actionCanvasMatrix 转换页面坐标矩阵，不翻转Y轴
 // 入参: matrix 页面变换
 // 返回: canvas.Matrix 路径变换

ofdgo_renderer_measure_canvas.go

@@ -227,7 +227,11 @@ func (run *TextRun) addSpan(start, end int, bounds canvas.Rect, m canvas.Matrix,
 		if path.Empty() {
 			return
 		}
-		bounds = path.Transform(m.Inv()).Bounds()
+		inverse, ok := invertCanvasMatrix(m)
+		if !ok {
+			return
+		}
+		bounds = path.Transform(inverse).Bounds()
 	}
 	if bounds.W() < 0 || bounds.H() <= 0 {
 		return
@@ -238,8 +242,8 @@ func (run *TextRun) addSpan(start, end int, bounds canvas.Rect, m canvas.Matrix,
 		span = run.Spans[n-1]
 		v := span.Matrix
 		previous := canvas.Matrix{{v[0], v[2], v[4]}, {v[1], v[3], v[5]}}
-		if previous.Det() != 0 {
+		if inverse, ok := invertCanvasMatrix(previous); ok {
-			bounds = canvas.Rect{X1: 1, Y1: 1}.Add(canvas.Rect{X1: 1, Y1: 1}.Transform(previous.Inv().Mul(m)))
+			bounds = canvas.Rect{X1: 1, Y1: 1}.Add(canvas.Rect{X1: 1, Y1: 1}.Transform(inverse.Mul(m)))
 			m = previous.Translate(bounds.X0, bounds.Y0).Scale(bounds.W(), bounds.H())
 		}
 		run.Spans = run.Spans[:n-1]

ofdgo_renderer_state_canvas.go

@@ -34,6 +34,9 @@ type canvasFontKey struct {
 // canvasClipCacheKey 区分不依赖文档资源的共享裁剪缓存
 type canvasClipCacheKey struct{}
 
+// canvasClipUnionKey 区分文字和图形裁剪的共享并集缓存
+type canvasClipUnionKey struct{}
+
 // canvasPathCacheKey 区分不依赖文档资源的共享局部路径缓存
 type canvasPathCacheKey struct{}
 
@@ -83,6 +86,21 @@ func (r *Renderer) canvasClipIntersections() *renderCache[[32]byte, *canvas.Path
 	return cache
 }
 
+// canvasClipUnions 复用相同输入轮廓的裁剪并集，不改变布尔运算顺序
+// 返回: *renderCache[[32]byte, *canvas.Path] 只读裁剪并集缓存
+func (r *Renderer) canvasClipUnions() *renderCache[[32]byte, *canvas.Path] {
+	key := canvasClipUnionKey{}
+	if state, ok := r.sharedBackendStates[key]; ok {
+		return state.(*renderCache[[32]byte, *canvas.Path])
+	}
+	if r.sharedBackendStates == nil {
+		r.sharedBackendStates = make(map[any]any)
+	}
+	cache := resourceCache[[32]byte, *canvas.Path](r.Reader.resources, 8<<20)
+	r.sharedBackendStates[key] = cache
+	return cache
+}
+
 // canvasParsedPaths 获取子渲染器共享的局部路径缓存，不保留对象变换
 // 返回: *renderCache[canvasPathKey, *canvas.Path] 路径缓存
 func (r *Renderer) canvasParsedPaths() *renderCache[canvasPathKey, *canvas.Path] {

ofdgo_writer.go

@@ -146,6 +146,19 @@ func (e *Editor) Snapshot(ctx context.Context) (*Editor, error) {
 	}
 	snapshot.revision, snapshot.serial, snapshot.saveTarget = e.revision, e.serial, e.saveTarget
 	snapshot.backends, snapshot.fontDirs, snapshot.fontFS = e.backends, slices.Clone(e.fontDirs), slices.Clone(e.fontFS)
+	for _, resource := range e.resources {
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+		if resource.font == nil || resource.font.FontFile == "" || !next.fileNames[resource.name] {
+			continue
+		}
+		data, err := next.readFileViewContext(ctx, resource.name)
+		if err != nil {
+			return nil, err
+		}
+		snapshot.resources = append(snapshot.resources, editorResource{name: resource.name, data: data, font: cloneEditorData(resource.font)})
+	}
 	if e.source != nil {
 		snapshot.source.retiredAttachments = maps.Clone(e.source.retiredAttachments)
 		snapshot.source.removedAttachments = maps.Clone(e.source.removedAttachments)