feat(渲染逻辑): 完善图片另存与缺字体处理

assets/webui/index.html

@@ -140,6 +140,7 @@
 					<option value="contain">适应</option>
 					<option value="cover">填充</option>
 				</select>
+				<button id="saveImageButton" class="button" type="button" disabled>另存</button>
 				<button id="cropImageButton" class="button" type="button" aria-label="裁剪图片" aria-pressed="false" disabled>裁剪</button>
 				<button id="resetCropButton" class="button" type="button" aria-label="还原图片" disabled>还原</button>
 				<span>图片</span>

assets/webui/ofdgo.css

@@ -86,6 +86,7 @@ a:focus-visible {
 }
 
 .editor-toolbar {
+	--editor-control-width: 58px;
 	display: flex;
 	max-height: 40dvh;
 	overflow: auto;
@@ -103,8 +104,8 @@ a:focus-visible {
 	display: grid;
 	flex: 1 0 auto;
 	justify-content: center;
-	grid-template-columns: repeat(3, max-content);
+	grid-template-columns: repeat(3, var(--editor-control-width));
-	grid-template-rows: repeat(2, 28px) 16px;
+	grid-template-rows: repeat(2, var(--control-height)) 16px;
 	column-gap: 4px;
 	row-gap: 4px;
 	padding: 0 8px;
@@ -112,17 +113,29 @@ a:focus-visible {
 }
 
 .editor-image {
-	grid-template-columns: repeat(2, max-content);
+	grid-template-columns: repeat(2, var(--editor-control-width));
 }
 
 .editor-actions,
 .editor-transform,
 .editor-erase {
-	grid-template-columns: max-content;
+	grid-template-columns: var(--editor-control-width);
 }
 
-.editor-image > select {
+.editor-group > .button,
-	grid-column: 1 / -1;
+.editor-group > select {
+	min-width: 0;
+	width: 100%;
+}
+
+.editor-group > select {
+	height: var(--control-height);
+	padding: 0 4px;
+	border: 1px solid var(--line-strong);
+	border-radius: 0;
+	background: #fff;
+	color: #1f2428;
+	text-align: center;
 }
 
 .editor-paragraph > .editor-field,
@@ -131,11 +144,11 @@ a:focus-visible {
 }
 
 .editor-objects {
-	grid-template-columns: repeat(4, max-content);
+	grid-template-columns: repeat(4, var(--editor-control-width));
 }
 
 .editor-group:has(#penTool) {
-	grid-template-columns: repeat(4, max-content);
+	grid-template-columns: repeat(4, var(--editor-control-width));
 }
 
 .object-picker-list {
@@ -208,7 +221,7 @@ a:focus-visible {
 }
 
 .editor-paragraph {
-	grid-template-columns: 54px 120px;
+	grid-template-columns: var(--editor-control-width) 120px;
 }
 
 .editor-group:has(#shapeFill) {
@@ -2917,6 +2930,10 @@ button.outline-link:hover {
 }
 
 @media (min-width: 901px) and (max-width: 1600px) and (pointer: fine) {
+	.editor-toolbar {
+		--editor-control-width: 54px;
+	}
+
 	.editor-group {
 		padding-inline: 3px;
 		column-gap: 3px;
@@ -2931,7 +2948,7 @@ button.outline-link:hover {
 	}
 
 	.editor-paragraph {
-		grid-template-columns: 54px 108px;
+		grid-template-columns: var(--editor-control-width) 108px;
 	}
 
 	.toolbar {

assets/webui/ofdgo.js

@@ -204,6 +204,7 @@ const el = {
 	objectFlip: document.querySelector("#objectFlip"),
 	imageFit: document.querySelector("#imageFit"),
 	cropImageButton: document.querySelector("#cropImageButton"),
+	saveImageButton: document.querySelector("#saveImageButton"),
 	resetCropButton: document.querySelector("#resetCropButton"),
 	multiSelectButton: document.querySelector("#multiSelectButton"),
 	textAlign: document.querySelector("#textAlign"),
@@ -1523,7 +1524,7 @@ function openObjectStyle() {
 	const shared = (key, fallback) => items.every(item => (item[key] ?? fallback) === (items[0][key] ?? fallback)) ? items[0][key] ?? fallback : null;
 	el.objectLinkFields.hidden = items.length !== 1 || items[0].scoped;
 	const link = items[0].link ? JSON.parse(items[0].link) : null;
-	const targetPage = link?.Goto?.Dest ? state.doc.pages.findIndex(page => page.id === link.Goto.Dest.PageID) : -1;
+	const targetPage = link?.Goto?.Dest ? pageIndexByID(state.doc.pages, link.Goto.Dest.PageID) : -1;
 	el.objectLinkKind.value = items[0].linkCount > 1 ? "keep" : link?.URI ? "uri" : targetPage >= 0 ? "page" : link ? "keep" : "none";
 	el.objectLinkKind.disabled = items[0].linkCount > 1;
 	el.objectLinkAddress.value = link?.URI?.URI || "";
@@ -2769,7 +2770,7 @@ async function changeDocument(name, item, ...args) {
 		const clipboard = state.objectClipboard;
 		if (reindexed && clipboard?.scope?.startsWith(reindexed.scope + "/") && clipboard.page === reindexed.page) state.objectClipboard = null;
 		const location = name === "ofdgoUndo" ? view?.before : view?.after;
-		const restoredIndex = location ? doc.pages.findIndex(page => page.id === location.page) : -1;
+		const restoredIndex = location ? pageIndexByID(doc.pages, location.page) : -1;
 		if (restoredIndex >= 0) {
 			state.composite = location.scope ? { index: restoredIndex, key: location.scope, objects: [] } : null;
 		} else if (!item && !inserting && !editingAnnotation && !(name === "ofdgoPasteObjects" && args[4])) {
@@ -2810,7 +2811,7 @@ async function changeDocument(name, item, ...args) {
 		if (item || name === "ofdgoPasteObjects" || inserting || editingAnnotation) {
 			await refreshEditorPage(doc, item ? item.index : args[0], openSeq, clearSelection);
 		} else {
-			const samePage = doc.pages.findIndex((page) => page.id === previous.id);
+			const samePage = pageIndexByID(doc.pages, previous.id);
 			const pageIndex = restoredIndex >= 0 ? restoredIndex : doc.pageIndex ?? (samePage < 0 ? Math.min(state.pageIndex, doc.pageCount - 1) : samePage);
 			const page = doc.pages[pageIndex];
 			const keepScroll = doc.pageIndex === undefined && page.id === previous.id && pageIndex === state.pageIndex
@@ -4120,7 +4121,7 @@ async function openDocument(options = {}) {
 					if (preview) state.pageCache.set(page.index, { ...preview, previewOnly: true });
 				}
 			}
-			const indices = new Set([pageIndex, ...doc.pages.filter((page) => previewIDs.includes(page.id)).map((page) => page.index)]);
+			const indices = new Set([pageIndex, ...previewIDs.map(id => pageIndexByID(doc.pages, id)).filter(index => index >= 0)]);
 			for (const index of indices) {
 				await loadPageData(index, { openSeq, priority: 0, refresh: true });
 				if (openSeq !== state.openSeq) {
@@ -4282,28 +4283,46 @@ async function renderPage(index, options = {}) {
 	}
 }
 
-async function downloadAttachment(attachment) {
+function downloadAttachment(attachment) {
+	return downloadResource(attachment, "ofdgoExportAttachment", "附件");
+}
+
+async function saveDocumentImage(resource) {
+	if (!resource || !state.doc || document.body.hasAttribute("aria-busy")) return;
+	const seq = state.openSeq;
+	try {
+		const image = await callWASM("ofdgoImages", resource);
+		if (seq !== state.openSeq) return;
+		await downloadResource({id: image.id, fileName: image.name}, "ofdgoExportImages", "图片");
+	} catch (err) {
+		if (seq === state.openSeq) showError(err, false);
+	}
+}
+
+el.saveImageButton.addEventListener("click", () => saveDocumentImage(canvasEditor.selected?.imageResource));
+
+async function downloadResource(attachment, api, label) {
 	if (!state.doc || document.body.hasAttribute("aria-busy")) {
 		return;
 	}
-	if (state.doc.encryption?.encrypted && !window.confirm("附件将按明文下载，是否继续？")) return;
+	if (state.doc.encryption?.encrypted && !window.confirm(`${label}将按明文下载，是否继续？`)) return;
 	const openSeq = state.openSeq;
 	state.exporting = true;
 	updateControls();
-	setBusy(true, "正在读取附件", null, "正在读取附件");
+	setBusy(true, `正在读取${label}`, null, `正在读取${label}`);
 	try {
 		const file = window.showSaveFilePicker ? await window.showSaveFilePicker({ suggestedName: attachment.fileName }) : null;
 		if (openSeq !== state.openSeq) {
 			return;
 		}
-		const result = await callWASM("ofdgoExportAttachment", attachment.id, file);
+		const result = await callWASM(api, attachment.id, file);
 		if (openSeq !== state.openSeq) {
 			return;
 		}
 		if (result.blob) {
 			downloadBytes(result.blob, result.mime, attachment.fileName);
 		}
-		setStatus(`附件已下载（${formatBytes(result.size)}）`);
+		setStatus(`${label}已下载（${formatBytes(result.size)}）`);
 	} catch (err) {
 		if (openSeq === state.openSeq) {
 			if (err.name === "AbortError") {
@@ -5531,7 +5550,7 @@ function mountPageSVG(index, page, openSeq = state.openSeq) {
 
 function pageLinkTarget(link) {
 	if (link.dest) {
-		const target = state.doc.pages.findIndex(page => page.id === link.dest.pageID);
+		const target = pageIndexByID(state.doc.pages, link.dest.pageID);
 		return { href: target < 0 ? "#" : `#page-${target + 1}`, title: target < 0 ? "文档链接" : `第${target + 1}页`, activate: () => navigateDestination(link.dest) };
 	}
 	if (link.attachment) {
@@ -5621,7 +5640,7 @@ function sourcePoint(page, x, y) {
 
 async function navigateDestination(dest) {
 	if (document.body.hasAttribute("aria-busy")) return;
-	const index = state.doc.pages.findIndex(page => page.id === dest.pageID);
+	const index = pageIndexByID(state.doc.pages, dest.pageID);
 	if (index < 0) {
 		setStatus("目标页面不存在");
 		return;
@@ -6498,9 +6517,21 @@ function createOutlineList(outlines, path = []) {
 	return list;
 }
 
+const pageIndexes = new WeakMap();
+
+function pageIndexByID(pages, id) {
+	let indexes = pageIndexes.get(pages);
+	if (!indexes) {
+		indexes = new Map(pages.map((page, position) => [page.id, {page, position}]));
+		pageIndexes.set(pages, indexes);
+	}
+	const entry = indexes.get(id);
+	return entry ? entry.page.index ?? entry.position : -1;
+}
+
 function selectedPageIndexes() {
 	if (!state.pageSelection.size) return state.pageMultiSelect ? [] : [state.pageIndex];
-	return state.doc.pages.filter(page => state.pageSelection.has(page.id)).map(page => page.index);
+	return [...state.pageSelection].map(id => pageIndexByID(state.doc.pages, id)).filter(index => index >= 0).sort((a, b) => a - b);
 }
 
 function changeSelectedPages(action, direction = 0) {
@@ -6546,7 +6577,7 @@ function selectThumbnailPage(event, index) {
 		const page = state.doc.pages[index], additive = event.ctrlKey || event.metaKey || state.pageMultiSelect;
 		if (!additive) state.pageSelection.clear();
 		if (event.shiftKey) {
-			let anchor = state.doc.pages.findIndex(page => page.id === state.pageSelectionAnchor);
+			let anchor = pageIndexByID(state.doc.pages, state.pageSelectionAnchor);
 			if (anchor < 0) anchor = state.pageIndex;
 			for (let i = Math.min(anchor, index); i <= Math.max(anchor, index); i++) state.pageSelection.add(state.doc.pages[i].id);
 		} else {
@@ -7859,6 +7890,7 @@ function updateObjectControls(item, reset = false) {
 	el.objectAlign.disabled = disabled || cropping || !canEditObject(item, "arrange");
 	el.objectRotate.disabled = el.objectFlip.disabled = disabled || cropping || !canEditObject(item, state.composite ? "transform" : "arrange");
 	el.cropImageButton.disabled = disabled || item.type !== "ImageObject" || !canEditObject(item, "cropImage");
+	el.saveImageButton.disabled = disabled || !item.imageResource;
 	el.imageFit.disabled = el.cropImageButton.disabled || cropping || Boolean(item.scoped && !canEditObject(item, "fitImage"));
 	el.cropImageButton.textContent = cropping ? "完成" : "裁剪";
 	el.cropImageButton.setAttribute("aria-label", cropping ? "完成裁剪" : "裁剪图片");
@@ -7958,7 +7990,7 @@ async function callWASM(name, ...args) {
 			request.fontData = new Map();
 			args.push([...request.localFonts.keys()]);
 		}
-		if (name === "ofdgoConvertPDF" || name === "ofdgoExportPage" || name === "ofdgoExportDocument" || name === "ofdgoExportAttachment" || name === "ofdgoSaveDocument" || name === "ofdgoSaveEncrypted" || name === "ofdgoSaveSigned" || name === "ofdgoImportPages") {
+		if (name === "ofdgoExportImages" || name === "ofdgoConvertPDF" || name === "ofdgoExportPage" || name === "ofdgoExportDocument" || name === "ofdgoExportAttachment" || name === "ofdgoSaveDocument" || name === "ofdgoSaveEncrypted" || name === "ofdgoSaveSigned" || name === "ofdgoImportPages") {
 			state.exportRequestID = id;
 			el.cancelExportButton.hidden = false;
 			el.cancelExportButton.disabled = false;

assets/webui/ofdgo_wasm.js

@@ -29,7 +29,7 @@ self.onmessage = ({ data }) => {
 		operations.get(data.id)?.abort();
 		return;
 	}
-	if (data.name === "ofdgoConvertFile" || data.name === "ofdgoPackFiles" || data.name === "ofdgoConvertPDF" || data.name === "ofdgoExportPage" || data.name === "ofdgoExportDocument" || data.name === "ofdgoExportAttachment" || data.name === "ofdgoSaveDocument" || data.name === "ofdgoSaveEncrypted" || data.name === "ofdgoSaveSigned" || data.name === "ofdgoImportPages") {
+	if (data.name === "ofdgoExportImages" || data.name === "ofdgoConvertFile" || data.name === "ofdgoPackFiles" || data.name === "ofdgoConvertPDF" || data.name === "ofdgoExportPage" || data.name === "ofdgoExportDocument" || data.name === "ofdgoExportAttachment" || data.name === "ofdgoSaveDocument" || data.name === "ofdgoSaveEncrypted" || data.name === "ofdgoSaveSigned" || data.name === "ofdgoImportPages") {
 		operations.set(data.id, new AbortController());
 	}
 	pending = pending.then(() => data.name === "ofdgoConvertFile" || data.name === "ofdgoPackFiles" ? handleBatchMessage(data) : handleMessage(data));

assets/webui/ofdgo_work.js

@@ -74,7 +74,8 @@ async function isBundleComplete(bundle) {
 	}
 	const cache = await caches.open(bundle.name);
 	const keys = await cache.keys();
-	return bundle.assets.every((url) => keys.some((key) => key.url === url));
+	const urls = new Set(keys.map(key => key.url));
+	return bundle.assets.every(url => urls.has(url));
 }
 
 async function currentBundle(meta) {

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 v0.0.0-20260928121523-d13a51030150
+	github.com/xiaoqidun/pdfgo v0.0.0-20260928145637-87d467fc8ef1
 	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 v0.0.0-20260928121523-d13a51030150 h1:N4JwW+p/KtgiNeNGVEdqswfLvefqZXGeS6tPpYKpIJQ=
+github.com/xiaoqidun/pdfgo v0.0.0-20260928145637-87d467fc8ef1 h1:meZvn/eb/AAbr6qfsP41UZZsW/g1v67a2CUYGzoJpS0=
-github.com/xiaoqidun/pdfgo v0.0.0-20260928121523-d13a51030150/go.mod h1:4Pf0JO0BEf1uzRY+uZjlMjN/OPn3PYa0YMi6cqPPTLQ=
+github.com/xiaoqidun/pdfgo v0.0.0-20260928145637-87d467fc8ef1/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=

internal/webui/wasm.go

@@ -204,6 +204,8 @@ func RunWASM() {
 	registerAsyncCallback("ofdgoExportPage", exportPage)
 	registerAsyncCallback("ofdgoExportDocument", exportDocument)
 	registerAsyncCallback("ofdgoExportAttachment", exportAttachment)
+	registerCallback("ofdgoImages", documentImages)
+	registerAsyncCallback("ofdgoExportImages", exportImages)
 	registerCallback("ofdgoMatchFontFiles", matchFontFiles)
 	registerCallback("ofdgoFontFaces", fontFaces)
 	registerCallback("ofdgoFontFace", fontFace)
@@ -651,6 +653,49 @@ func documentInfo(args []js.Value) (any, error) {
 	return currentSession.Details(), nil
 }
 
+// documentImages 读取当前文档的原始图片目录
+// 入参: args 浏览器参数
+// 返回: any 图片目录, error 读取错误
+func documentImages(args []js.Value) (any, error) {
+	if currentSession == nil {
+		return nil, fmt.Errorf("ofd document is not opened")
+	}
+	if len(args) != 0 {
+		return currentSession.Reader.Image(context.Background(), args[0].String())
+	}
+	return currentSession.Reader.Images(context.Background())
+}
+
+// exportImages 分块保存单幅原始图片或图片归档
+// 入参: args 图片标识和写出回调，空标识保存全部
+// 返回: any 文件类型, error 读写错误
+func exportImages(args []js.Value) (any, error) {
+	if currentSession == nil {
+		return nil, fmt.Errorf("ofd document is not opened")
+	}
+	writer := bufio.NewWriterSize(exportWriter{write: args[1]}, 1<<20)
+	mime := "application/octet-stream"
+	if id := args[0].String(); id != "" {
+		input, err := currentSession.Reader.OpenImage(context.Background(), id)
+		if err != nil {
+			return nil, err
+		}
+		defer input.Close()
+		if _, err := io.Copy(writer, input); err != nil {
+			return nil, err
+		}
+	} else {
+		mime = "application/zip"
+		if err := currentSession.Reader.WriteImages(context.Background(), writer); err != nil {
+			return nil, err
+		}
+	}
+	if err := writer.Flush(); err != nil {
+		return nil, err
+	}
+	return successResult(map[string]any{"mime": mime}), nil
+}
+
 // exportAttachment 分块导出附件
 // 入参: args 浏览器参数
 // 返回: any 附件数据, error 错误信息
@@ -736,6 +781,20 @@ func renderPage(args []js.Value) (any, error) {
 		return nil, err
 	}
 	links := make([]any, len(page.Links))
+	attachmentNames := make(map[string]string)
+	for _, link := range page.Links {
+		if link.Attachment == "" {
+			continue
+		}
+		attachments, err := currentSession.Reader.Attachments()
+		if err != nil {
+			return nil, err
+		}
+		for _, attachment := range attachments {
+			attachmentNames[attachment.ID] = path.Base(currentSession.Reader.ResPath(attachment.FileLoc))
+		}
+		break
+	}
 	for i, link := range page.Links {
 		item := map[string]any{
 			"uri":    link.URI,
@@ -748,13 +807,7 @@ func renderPage(args []js.Value) (any, error) {
 		}
 		if link.Attachment != "" {
 			item["attachment"] = link.Attachment
-			attachments, _ := currentSession.Reader.Attachments()
+			item["fileName"] = attachmentNames[link.Attachment]
-			for _, attachment := range attachments {
-				if attachment.ID == link.Attachment {
-					item["fileName"] = path.Base(currentSession.Reader.ResPath(attachment.FileLoc))
-					break
-				}
-			}
 		}
 		if dest := link.Dest; dest != nil {
 			item["dest"] = map[string]any{"type": dest.Type, "pageID": dest.PageID, "left": dest.Left, "top": dest.Top,
@@ -1184,6 +1237,9 @@ func editorObjects(index int, text *ofdgo.PageText) ([]any, error) {
 					}
 					item["imageBounds"] = editorBox(full)
 				}
+				if object.Type == "ImageObject" {
+					item["imageResource"] = object.ImageObject.ResourceID
+				}
 				if object.Type == "TextObject" {
 					item["bounds"] = editorBox(box)
 					value, layout := object.TextObject.TextLayout()
@@ -2114,6 +2170,9 @@ func compositeObjects(args []js.Value) (any, error) {
 		item := map[string]any{"id": fmt.Sprintf("%s/%d", key, i), "type": member.Object.Type, "x": box.X, "y": box.Y, "width": box.W, "height": box.H, "order": i, "position": member.Position.Index, "count": member.Position.Count, "container": key + ":" + member.Position.Container, "scoped": true, "contours": member.Contours,
 			"capabilities": editorCapabilities(member.Capabilities, member.Object.Type)}
 		editorAppearance(item, member.Object, member.Capabilities.Paint, member.StrokeScale)
+		if member.Object.Type == "ImageObject" {
+			item["imageResource"] = member.Object.ImageObject.ResourceID
+		}
 		if kind, geometry := member.Shape(); kind != "" {
 			item["shape"], item["geometry"] = string(kind), editorBox(geometry)
 		} else if kind, box, matrix := member.ShapeFrame(); kind != "" {

ofdgo_extract_image.go

@@ -0,0 +1,253 @@
+// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ofdgo
+
+import (
+	"archive/zip"
+	"context"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"path"
+	"slices"
+	"strings"
+)
+
+// ImageInfo 描述文档内的原始图片资源，独立蒙版保留为独立资源
+// 不包含对象裁剪、旋转、透明度及显示尺寸，不代表页面合成后的外观
+type ImageInfo struct {
+	ID       string `json:"id"`
+	Name     string `json:"name"`
+	Format   string `json:"format"`
+	Location string `json:"-"`
+}
+
+// imageOutput 在分块写出图片时检查调用方取消状态
+type imageOutput struct {
+	context context.Context
+	writer  io.Writer
+}
+
+// imageInput 在读取原始图片时检查调用方取消状态
+type imageInput struct {
+	io.ReadCloser
+	context context.Context
+}
+
+// Read 检查取消状态后读取原始数据
+// 入参: data 数据缓冲区
+// 返回: int 读取字节数, error 读取或取消错误
+func (r imageInput) Read(data []byte) (int, error) {
+	if err := r.context.Err(); err != nil {
+		return 0, err
+	}
+	return r.ReadCloser.Read(data)
+}
+
+// Write 检查取消状态后写出原始数据
+// 入参: data 数据块
+// 返回: int 写入字节数, error 写入或取消错误
+func (w imageOutput) Write(data []byte) (int, error) {
+	if err := w.context.Err(); err != nil {
+		return 0, err
+	}
+	return w.writer.Write(data)
+}
+
+// Images 列出文档、页面和模板声明的图片资源，不解码图片像素
+// 包含未使用及重复引用的资源声明，同一资源标识只返回一次
+// 入参: ctx 取消上下文
+// 返回: []ImageInfo 图片资源, error 读取或取消错误
+func (r *Reader) Images(ctx context.Context) ([]ImageInfo, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	if r.imageCatalog != nil {
+		return slices.Clone(r.imageCatalog), nil
+	}
+	doc, err := r.Doc()
+	if err != nil {
+		return nil, err
+	}
+	resources := make([]string, 0)
+	for _, name := range append(slices.Clone(doc.CommonData.DocumentRes), doc.CommonData.PublicRes...) {
+		resources = append(resources, r.ResPath(name))
+	}
+	pages := slices.Clone(doc.Pages.Page)
+	for _, template := range doc.CommonData.TemplatePage {
+		pages = append(pages, Page{BaseLoc: template.BaseLoc})
+	}
+	for _, page := range pages {
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+		header, err := r.readPageHeader(page)
+		if err != nil {
+			return nil, err
+		}
+		for _, name := range header.PageRes {
+			resources = append(resources, resolveResourcePath(r.ResPath(page.BaseLoc), "", name))
+		}
+	}
+	seen := make(map[string]bool)
+	ids := make(map[string]ImageInfo)
+	items := make([]ImageInfo, 0)
+	for _, name := range resources {
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+		if seen[name] {
+			continue
+		}
+		seen[name] = true
+		data, err := r.readFile(name)
+		if err != nil {
+			return nil, err
+		}
+		var res Res
+		if err := xml.Unmarshal(data, &res); err != nil {
+			return nil, err
+		}
+		for _, media := range res.MultiMedias.MultiMedia {
+			if media.Type != "Image" {
+				continue
+			}
+			location := resolveResourcePath(name, res.BaseLoc, media.MediaFile)
+			if media.ID == "" || location == "" {
+				return nil, fmt.Errorf("invalid image resource")
+			}
+			item := ImageInfo{ID: media.ID, Name: path.Base(location), Format: media.Format, Location: location}
+			if previous, ok := ids[item.ID]; ok {
+				if previous != item {
+					return nil, fmt.Errorf("conflicting image resource %q", item.ID)
+				}
+				continue
+			}
+			ids[item.ID] = item
+			items = append(items, item)
+		}
+	}
+	r.imageCatalog = items
+	return slices.Clone(items), nil
+}
+
+// Image 查找指定图片，已加载资源直接读取所在资源文件，不扫描其他页面
+// 入参: ctx 取消上下文, id 图片资源标识
+// 返回: ImageInfo 图片资源, error 读取或取消错误
+func (r *Reader) Image(ctx context.Context, id string) (ImageInfo, error) {
+	if err := ctx.Err(); err != nil {
+		return ImageInfo{}, err
+	}
+	if name := r.resourceFiles[id]; name != "" {
+		data, err := r.readFile(name)
+		if err != nil {
+			return ImageInfo{}, err
+		}
+		var res Res
+		if err := xml.Unmarshal(data, &res); err != nil {
+			return ImageInfo{}, err
+		}
+		for _, media := range res.MultiMedias.MultiMedia {
+			if media.ID == id && media.Type == "Image" && media.MediaFile != "" {
+				location := resolveResourcePath(name, res.BaseLoc, media.MediaFile)
+				return ImageInfo{ID: id, Name: path.Base(location), Format: media.Format, Location: location}, nil
+			}
+		}
+		return ImageInfo{}, fmt.Errorf("image resource %q not found", id)
+	}
+	items, err := r.Images(ctx)
+	if err != nil {
+		return ImageInfo{}, err
+	}
+	for _, item := range items {
+		if item.ID == id {
+			return item, nil
+		}
+	}
+	return ImageInfo{}, fmt.Errorf("image resource %q not found", id)
+}
+
+// OpenImage 打开原始图片资源流，不解码、不重采样或重新压缩
+// 加密文档返回解密后的资源，调用方负责关闭并完整读取以校验ZIP数据
+// 入参: ctx 取消上下文, id 图片资源标识
+// 返回: io.ReadCloser 原始图片流, error 读取错误
+func (r *Reader) OpenImage(ctx context.Context, id string) (io.ReadCloser, error) {
+	item, err := r.Image(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+	input, err := r.openFile(item.Location)
+	if err != nil {
+		return nil, err
+	}
+	return imageInput{ReadCloser: input, context: ctx}, nil
+}
+
+// WriteImages 将原始图片逐个写入ZIP，不改变图片编码，文件序号避免同名覆盖
+// 入参: ctx 取消上下文, writer 输出流, ids 资源标识，省略则导出全部
+// 返回: error 读取、写出或取消错误
+func (r *Reader) WriteImages(ctx context.Context, writer io.Writer, ids ...string) error {
+	var items []ImageInfo
+	if len(ids) == 0 {
+		var err error
+		items, err = r.Images(ctx)
+		if err != nil {
+			return err
+		}
+	} else {
+		seen := make(map[string]bool)
+		for _, id := range ids {
+			if seen[id] {
+				continue
+			}
+			item, err := r.Image(ctx, id)
+			if err != nil {
+				return err
+			}
+			items = append(items, item)
+			seen[id] = true
+		}
+	}
+	archive := zip.NewWriter(imageOutput{ctx, writer})
+	for i, item := range items {
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+		name := strings.Map(func(c rune) rune {
+			if c < 32 || strings.ContainsRune(`<>:"/\|?*`, c) {
+				return '_'
+			}
+			return c
+		}, item.Name)
+		header := &zip.FileHeader{Name: fmt.Sprintf("%04d-%s", i+1, name), Method: zip.Store}
+		output, err := archive.CreateHeader(header)
+		if err != nil {
+			return err
+		}
+		input, err := r.openFile(item.Location)
+		if err != nil {
+			return err
+		}
+		_, err = io.Copy(imageOutput{ctx, output}, input)
+		closeErr := input.Close()
+		if err != nil {
+			return err
+		}
+		if closeErr != nil {
+			return closeErr
+		}
+	}
+	return archive.Close()
+}

ofdgo_geom_path.go

@@ -153,8 +153,19 @@ func objectGeometryPath(geometry GeometryBackend, object PathObject) (GeometryPa
 // 入参: path 填充路径
 // 返回: GeometryPath 显式闭合路径
 func closedGeometry(path GeometryPath) GeometryPath {
+	open, missing := false, false
+	for _, segment := range path {
+		if segment.Verb == GeometryMove && open {
+			missing = true
+			break
+		}
+		open = segment.Verb != GeometryClose
+	}
+	if !missing && !open {
+		return path
+	}
 	result := make(GeometryPath, 0, len(path)+1)
-	open := false
+	open = false
 	for _, segment := range path {
 		if segment.Verb == GeometryMove && open {
 			result = append(result, GeometrySegment{Verb: GeometryClose})

ofdgo_reader.go

@@ -36,6 +36,7 @@ type Reader struct {
 	ResMap                    map[string]string
 	resourcesRead             map[string]bool
 	resourceFiles             map[string]string
+	imageCatalog              []ImageInfo
 	fontCache                 map[string]*Font
 	fontResourcesRead         bool
 	fontFaces                 map[string][]*FontFace

ofdgo_renderer.go

@@ -21,6 +21,7 @@ import (
 
 // Renderer 渲染器实现
 // 通过NewRenderer创建，实例及共享的Reader需串行使用
+// 外部字体缺失且无可用回退时不绘制对应文字，其余内容继续；字体状态可通过FontInfos查询
 // OnPageText可选，接收页面绘制时同步提取的文字，不包含图案和签名外观
 // OnExportProgress可选，同步回报文档导出的已处理页数及总页数，返回错误则停止，页数完成不代表写入成功
 // TransparentBackground关闭页面白底，供嵌套图案和印章保持透明背景

ofdgo_renderer_font_loader_canvas.go

@@ -14,11 +14,7 @@
 
 package ofdgo
 
-import (
+import "github.com/tdewolff/canvas"
-	"fmt"
-
-	"github.com/tdewolff/canvas"
-)
 
 // loadFont 加载字体
 // 入参: fontID 字体ID
@@ -34,13 +30,6 @@ func (r *Renderer) loadFont(fontID string) *canvas.FontFamily {
 	}
 	of := r.Reader.fontCache[fontID]
 	if len(resolved.Data) == 0 {
-		if !r.textOnly {
-			name := fontID
-			if of != nil && of.FontName != "" {
-				name = of.FontName
-			}
-			r.renderError = fmt.Errorf("font %q is unavailable", name)
-		}
 		return nil
 	}
 	if of == nil {

ofdgo_sign_verify.go

@@ -883,13 +883,36 @@ func verifySignatureCertificateChain(cert *smx509.Certificate, pool, trusts [][]
 			if err != nil {
 				return err
 			}
-			group.pool.AddCert(ca)
+			addSignatureCertificate(group.pool, ca)
 		}
 	}
 	_, err := cert.Verify(smx509.VerifyOptions{Roots: roots, Intermediates: intermediates, CurrentTime: at, KeyUsages: []smx509.ExtKeyUsage{usage}})
 	return err
 }
 
+// addSignatureCertificate 添加证书并按RFC5280排除自颁发中间证书的路径长度
+// 入参: pool 证书池, cert 证书
+func addSignatureCertificate(pool *smx509.CertPool, cert *smx509.Certificate) {
+	if !cert.BasicConstraintsValid || cert.MaxPathLen < 0 {
+		pool.AddCert(cert)
+		return
+	}
+	copy := *cert
+	copy.MaxPathLen, copy.MaxPathLenZero = -1, false
+	pool.AddCertWithConstraint(&copy, func(chain []*smx509.Certificate) error {
+		length := 0
+		for i, intermediate := range chain {
+			if i > 0 && !bytes.Equal(intermediate.RawSubject, intermediate.RawIssuer) {
+				length++
+			}
+		}
+		if length > cert.MaxPathLen {
+			return smx509.CertificateInvalidError{Cert: cert, Reason: smx509.TooManyIntermediates}
+		}
+		return nil
+	})
+}
+
 // verifyCertificateSignature 验证证书签名
 // 入参: cert 证书信息, issuerCert 颁发者证书
 // 返回: bool 是否验证通过, error 错误信息