feat(创建编辑): 新增对象旋转、翻转与图片裁剪，修复框选颜色及变换边界问题

assets/webui/index.html

@@ -90,6 +90,21 @@
 				</select>
 				<span>对象</span>
 			</div>
+			<div class="editor-group editor-transform">
+				<select id="objectRotate" class="order-select" aria-label="对象旋转" disabled>
+					<option value="" hidden>旋转</option>
+					<option value="90">右转90°</option>
+					<option value="-90">左转90°</option>
+				</select>
+				<select id="objectFlip" class="order-select" aria-label="对象翻转" disabled>
+					<option value="" hidden>翻转</option>
+					<option value="horizontal">水平</option>
+					<option value="vertical">垂直</option>
+				</select>
+				<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>变换</span>
+			</div>
 			<div class="editor-group">
 				<div class="text-font"><select id="textFont" aria-label="字体" title="字体" disabled></select><button id="textFontAdd" class="icon-button" type="button" title="添加字体" aria-label="添加字体">+</button></div>
 				<div class="editor-number"><input id="textSize" type="number" min="1" step="any" required aria-label="字号" disabled><span>pt</span></div>

assets/webui/ofdgo.css

@@ -9,6 +9,7 @@
 	--page: #ffffff;
 	--text-muted: #66737f;
 	--accent: #0f7b68;
+	--accent-soft: rgba(15, 123, 104, 0.12);
 	--accent-strong: #095c4e;
 	--focus: #0f7b68;
 	--sidebar-width: clamp(220px, 20vw, 292px);
@@ -112,6 +113,7 @@ a:focus-visible {
 
 .editor-file,
 .editor-paragraph,
+.editor-transform,
 .editor-group:has(#textFont),
 .editor-group:has(#shapeFill) {
 	grid-template-columns: repeat(2, max-content);
@@ -1220,6 +1222,7 @@ button.outline-link:hover {
 	background: #fff;
 	outline: none;
 	resize: none;
+	transform-origin: 0 0;
 	font-kerning: none;
 	font-variant-ligatures: none;
 	letter-spacing: 0;
@@ -1273,7 +1276,8 @@ button.outline-link:hover {
 
 .edit-object:hover,
 .edit-object.selected,
-.edit-selection {
+.edit-selection,
+.edit-crop {
 	outline: calc(1px / var(--surface-scale)) solid var(--accent);
 }
 
@@ -1298,7 +1302,8 @@ button.outline-link:hover {
 }
 
 .selected .edit-handle,
-.edit-selection .edit-handle {
+.edit-selection .edit-handle,
+.edit-crop .edit-handle {
 	display: block;
 }
 
@@ -1306,11 +1311,28 @@ button.outline-link:hover {
 	display: none;
 }
 
-.edit-selection .edit-handle {
+.edit-selection .edit-handle,
+.edit-crop .edit-handle {
 	pointer-events: auto;
 	touch-action: none;
 }
 
+.edit-crop {
+	pointer-events: auto;
+	touch-action: none;
+	cursor: move;
+}
+
+.cropping .edit-object {
+	pointer-events: none;
+	outline: none;
+	background: none;
+}
+
+.cropping .edit-object .edit-handle {
+	display: none;
+}
+
 .edit-handle::before {
 	position: absolute;
 	inset: calc(-8px / var(--surface-scale));

assets/webui/ofdgo.js

@@ -93,6 +93,10 @@ const el = {
 	objectOrder: document.querySelector("#objectOrder"),
 	objectAlign: document.querySelector("#objectAlign"),
 	objectDistribute: document.querySelector("#objectDistribute"),
+	objectRotate: document.querySelector("#objectRotate"),
+	objectFlip: document.querySelector("#objectFlip"),
+	cropImageButton: document.querySelector("#cropImageButton"),
+	resetCropButton: document.querySelector("#resetCropButton"),
 	multiSelectButton: document.querySelector("#multiSelectButton"),
 	textAlign: document.querySelector("#textAlign"),
 	textWrap: document.querySelector("#textWrap"),
@@ -240,7 +244,13 @@ const canvasEditor = new CanvasEditor(el.viewerPanel, {
 	onTransform: (item, change) => changeDocument(item.items ? "ofdgoTransformObjects" : "ofdgoTransformObject", item,
 		change.x + item.x * (1 - change.scale), change.y + item.y * (1 - change.scale), change.scale),
 	onReshape: (item, box) => changeDocument("ofdgoReshapeObject", item, box.x, box.y, box.width, box.height),
-	onTextWidth: (item, box) => changeDocument("ofdgoLayoutText", item, box.x, box.width, true, item.align || "", item.paragraphHeight || 0),
+	onTextWidth: (item, box) => changeDocument("ofdgoLayoutText", item, box.x - item.x, box.width, true, item.align || "", item.paragraphHeight || 0),
+	onCrop: (item, box) => changeDocument("ofdgoCropImage", item, box.x, box.y, box.width, box.height),
+	onCropChange: () => {
+		updatePendingChanges();
+		updateObjectControls(canvasEditor.selected);
+		syncSelection();
+	},
 	onDelete: (item) => changeDocument(item.items ? "ofdgoDeleteObjects" : "ofdgoDeleteObject", item),
 	onEdit: editCanvasObject,
 	drawStyle: shapeStyle,
@@ -253,8 +263,7 @@ const canvasEditor = new CanvasEditor(el.viewerPanel, {
 		: changeDocument("ofdgoUpdateText", item, value, fontData || null, item.size, null),
 	onTextChange: () => {
 		const editing = canvasEditor.input;
-		setDirty(state.editing && (state.editorInfo?.revision !== state.savedRevision
+		updatePendingChanges();
-			|| Boolean(editing && (editing.input.value !== editing.item.text || editing.fontData))));
 		if (!editing) {
 			updateTextFonts(canvasEditor.selected, true);
 			syncSelection();
@@ -262,14 +271,22 @@ const canvasEditor = new CanvasEditor(el.viewerPanel, {
 	},
 });
 
+// updatePendingChanges 将未提交的文字和裁剪计入修改状态，不生成历史记录。
+function updatePendingChanges() {
+	const editing = canvasEditor.input;
+	setDirty(state.editing && (state.editorInfo?.revision !== state.savedRevision
+		|| Boolean(editing && (editing.input.value !== editing.item.text || editing.fontData)) || canvasEditor.cropChanged()));
+}
+
 el.editorTools.addEventListener("pointerdown", (event) => {
 	if (canvasEditor.input && event.target.closest("button")) event.preventDefault();
 });
 
-// editorClick commits inline text before resolving the selection for a toolbar command.
+// editorClick 提交画布中的文字和裁剪后，再执行工具栏操作。
 function editorClick(button, action) {
 	button.addEventListener("click", async () => {
 		if (canvasEditor.input && !await canvasEditor.commitText()) return;
+		if (canvasEditor.crop && !await canvasEditor.commitCrop()) return;
 		return action();
 	});
 }
@@ -357,6 +374,30 @@ el.objectDistribute.addEventListener("change", () => {
 		return changeDocument("ofdgoDistributeObjects", canvasEditor.selected, axis);
 	}
 });
+for (const [select, method] of [[el.objectRotate, "ofdgoRotateObjects"], [el.objectFlip, "ofdgoFlipObjects"]]) {
+	select.addEventListener("change", () => {
+		const value = select.value, item = canvasEditor.selected;
+		select.value = "";
+		if (!item || !value || canvasEditor.crop) return;
+		return changeDocument(method, { ...item, id: canvasEditor.items().map(member => member.id) },
+			select === el.objectRotate ? Number(value) : value);
+	});
+}
+el.cropImageButton.addEventListener("click", () => {
+	if (document.body.hasAttribute("aria-busy")) return;
+	if (canvasEditor.crop) return canvasEditor.commitCrop();
+	const item = canvasEditor.selected;
+	if (item?.type === "ImageObject") canvasEditor.startCrop(item);
+});
+el.resetCropButton.addEventListener("click", () => {
+	if (document.body.hasAttribute("aria-busy")) return;
+	if (canvasEditor.crop) {
+		canvasEditor.closeCrop();
+		return;
+	}
+	const item = canvasEditor.selected;
+	if (item?.imageBounds) return canvasEditor.options.onCrop(item, item.imageBounds);
+});
 editorClick(el.undoButton, () => changeDocument("ofdgoUndo"));
 editorClick(el.redoButton, () => changeDocument("ofdgoRedo"));
 for (const [button, tool] of [[el.drawLineButton, "line"], [el.drawRectangleButton, "rectangle"], [el.drawEllipseButton, "ellipse"]]) {
@@ -760,12 +801,12 @@ function openInsertPanel(item = null) {
 	el.insertImage.focus();
 }
 
-// currentTextStyle returns the selected text style or the next text box's defaults.
+// currentTextStyle 获取所选文字样式，未选中文字时使用新文字的默认样式。
 function currentTextStyle() {
 	return canvasEditor.selected?.type === "TextObject" ? canvasEditor.selected : state.textDefaults;
 }
 
-// toggleTextTool places text directly on the page without creating empty document objects.
+// toggleTextTool 切换画布文字工具，不提前创建空文字对象。
 async function toggleTextTool() {
 	if (!state.editing || document.body.hasAttribute("aria-busy")) return;
 	if (canvasEditor.tool === "text") {
@@ -788,7 +829,7 @@ async function toggleTextTool() {
 	el.viewerPanel.focus({ preventScroll: true });
 }
 
-// beginCanvasText loads the chosen local font and starts an unsaved inline text box.
+// beginCanvasText 加载所选本地字体，并在画布上创建待提交的文字输入框。
 async function beginCanvasText(index, box, surface, page) {
 	const font = state.textDefaults.fontChoice || state.textFonts[Number(el.textFont.value)];
 	if (!font) {
@@ -848,7 +889,7 @@ function updateTextFonts(item, refresh = false) {
 	}
 }
 
-// changeTextFont preserves uncommitted text while loading a replacement font.
+// changeTextFont 更换字体时保留尚未提交的文字。
 async function changeTextFont() {
 	const item = canvasEditor.selected;
 	const font = state.textFonts[Number(el.textFont.value)];
@@ -940,7 +981,7 @@ function textPoints(size) {
 	return Number((size * 72 / 25.4).toFixed(2));
 }
 
-// changeParagraph keeps layout in the library and only submits changed form values.
+// changeParagraph 仅提交变更的段落选项，具体排版由库完成。
 async function changeParagraph(wrap = currentTextStyle().wrap) {
 	const item = currentTextStyle();
 	if (document.body.hasAttribute("aria-busy") || item.draft) return;
@@ -2253,9 +2294,10 @@ async function exportFile(whole, indices = null, value = el.exportFormat.value)
 		if (openSeq !== state.openSeq) {
 			return;
 		}
-		if (canvasEditor.input) {
+		if (canvasEditor.input || canvasEditor.crop) {
 			setBusy(false);
 			if (!await canvasEditor.commitText()) return;
+			if (!await canvasEditor.commitCrop()) return;
 			openSeq = state.openSeq;
 			setBusy(true, `正在生成 ${label}`, null, whole ? STATUS.exporting : STATUS.pageExporting);
 		}
@@ -2406,7 +2448,7 @@ function unmountPage(index) {
 	const shell = pageShell(index);
 	const selection = document.getSelection();
 	const range = !selection.isCollapsed && selection.rangeCount ? selection.getRangeAt(0) : null;
-	if (canvasEditor.input?.item.index === index
+	if (canvasEditor.input?.item.index === index || canvasEditor.crop?.item.index === index
 		|| range && (!state.documentSelection || !isDocumentSelection(range)) && range.intersectsNode(shell)) {
 		state.selectedPages.add(index);
 		return;
@@ -4160,7 +4202,17 @@ function updateObjectControls(item, reset = false) {
 	const disabled = !item || Boolean(item.draft) || !state.ready || state.exporting;
 	el.deleteObjectButton.disabled = el.objectAlign.disabled = disabled;
 	el.copyObjectButton.disabled = disabled;
-	el.objectDistribute.disabled = disabled || !item.items || item.items.length < 3;
+	const cropping = Boolean(canvasEditor.crop);
+	el.objectAlign.disabled = disabled || cropping;
+	el.objectRotate.disabled = el.objectFlip.disabled = disabled || cropping;
+	el.cropImageButton.disabled = disabled || item.type !== "ImageObject";
+	el.cropImageButton.textContent = cropping ? "完成" : "裁剪";
+	el.cropImageButton.setAttribute("aria-label", cropping ? "完成裁剪" : "裁剪图片");
+	el.cropImageButton.setAttribute("aria-pressed", String(cropping));
+	el.resetCropButton.textContent = cropping ? "取消" : "还原";
+	el.resetCropButton.setAttribute("aria-label", cropping ? "取消裁剪" : "还原图片");
+	el.resetCropButton.disabled = disabled || !cropping && (!item.imageBounds || ["x", "y", "width", "height"].every(key => Math.abs(item[key] - item.imageBounds[key]) < 1e-9));
+	el.objectDistribute.disabled = disabled || cropping || !item.items || item.items.length < 3;
 	el.editObjectButton.disabled = disabled || Boolean(item.items) || item.type === "PathObject";
 	el.multiSelectButton.disabled = !state.editing || !canvasEditor.enabled || !state.ready || state.exporting;
 	const text = item?.type === "TextObject" ? item : state.textDefaults;
@@ -4197,7 +4249,7 @@ function updateObjectControls(item, reset = false) {
 	const count = members[0]?.count || 0;
 	const canRaise = orders.some((order, i) => order !== count - orders.length + i);
 	const canLower = orders.some((order, i) => order !== i);
-	el.objectOrder.disabled = disabled || count <= orders.length;
+	el.objectOrder.disabled = disabled || cropping || count <= orders.length;
 	for (const option of el.objectOrder.options) {
 		option.disabled = disabled || (["up", "top"].includes(option.value) ? !canRaise : !canLower);
 	}

assets/webui/ofdgo_edit.js

@@ -21,14 +21,14 @@ export function objectTransform(box, dx, dy, corner = "") {
 	return { x: left ? box.width * (1 - scale) : 0, y: top ? box.height * (1 - scale) : 0, scale };
 }
 
-// selectionBounds keeps same-page objects together without changing their relative positions.
+// selectionBounds 计算同页对象的联合边界，不改变对象位置。
 export function selectionBounds(items) {
 	const x = Math.min(...items.map(item => item.x)), y = Math.min(...items.map(item => item.y));
 	return { x, y, width: Math.max(...items.map(item => item.x + item.width)) - x,
 		height: Math.max(...items.map(item => item.y + item.height)) - y };
 }
 
-// alignmentGuides marks the nearest edges or centers without changing object coordinates.
+// alignmentGuides 查找最近的边缘或中心辅助线，不改变对象坐标。
 function alignmentGuides(box, targets, tolerance) {
 	const lines = [];
 	for (const [axis, size, cross, span] of [["x", "width", "y", "height"], ["y", "height", "x", "width"]]) {
@@ -51,7 +51,26 @@ function alignmentGuides(box, targets, tolerance) {
 	return lines.join("");
 }
 
-// constrainedPoint preserves shape constraints without changing off-page geometry.
+// transformedBox 将本地矩形映射到页面，用于变换后的文字框预览。
+function transformedBox(box, matrix) {
+	const [a, b, c, d, e, f] = matrix;
+	const points = [[box.x, box.y], [box.x + box.width, box.y], [box.x, box.y + box.height], [box.x + box.width, box.y + box.height]]
+		.map(([x, y]) => [a * x + c * y + e, b * x + d * y + f]);
+	const x = Math.min(...points.map(p => p[0])), y = Math.min(...points.map(p => p[1]));
+	return { x, y, width: Math.max(...points.map(p => p[0])) - x, height: Math.max(...points.map(p => p[1])) - y };
+}
+
+// cropBox 将保留区域限制在当前图片范围内，不改变图片比例。
+function cropBox(box, bounds, dx, dy, corner) {
+	if (!corner) return { ...box, x: Math.max(bounds.x, Math.min(box.x + dx, bounds.x + bounds.width - box.width)),
+		y: Math.max(bounds.y, Math.min(box.y + dy, bounds.y + bounds.height - box.height)) };
+	const next = reshapeBox({ geometry: box }, dx, dy, corner, false);
+	const x = Math.max(bounds.x, next.x), y = Math.max(bounds.y, next.y);
+	return { x, y, width: Math.min(bounds.x + bounds.width, next.x + next.width) - x,
+		height: Math.min(bounds.y + bounds.height, next.y + next.height) - y };
+}
+
+// constrainedPoint 按修饰键约束图形端点，允许超出页面边界。
 export function constrainedPoint(from, to, shape, shift) {
 	let dx = to.x - from.x, dy = to.y - from.y;
 	if (shift && shape === "line") {
@@ -68,7 +87,7 @@ export function constrainedPoint(from, to, shape, shift) {
 	return { x: from.x + dx, y: from.y + dy };
 }
 
-// reshapeBox moves line endpoints or resizes basic shapes without scaling their stroke.
+// reshapeBox 移动线段端点或调整基本图形范围，不缩放描边。
 export function reshapeBox(item, dx, dy, handle, shift) {
 	const box = item.geometry;
 	if (!dx && !dy && !shift) return { ...box };
@@ -93,7 +112,7 @@ export function reshapeBox(item, dx, dy, handle, shift) {
 	return { x, y, width: right - x, height: bottom - y };
 }
 
-// paintShape uses the same page-space geometry for creation and endpoint previews.
+// paintShape 使用统一的页面坐标绘制图形及端点调整预览。
 function paintShape(node, shape, box) {
 	const { x, y, width, height } = box;
 	const attributes = shape === "line" ? { x1: x, y1: y, x2: x + width, y2: y + height }
@@ -152,6 +171,8 @@ export class CanvasEditor {
 	}
 
 	mount(index, page, surface) {
+		const crop = this.crop?.item.index === index ? this.crop : null;
+		if (crop) this.closeCrop();
 		const pending = this.pendingSelection?.index === index;
 		const selected = pending ? this.pendingSelection.ids || page.objects.slice(-1).map(item => item.id)
 			: this.items().filter(item => item.index === index).map(item => item.id);
@@ -189,6 +210,12 @@ export class CanvasEditor {
 		surface.append(layer);
 		if (selected.length) this.setSelection(selection);
 		if (pending) this.pendingSelection = null;
+		if (crop && selection.length === 1 && selection[0].id === crop.item.id
+			&& ["x", "y", "width", "height"].every(key => selection[0][key] === crop.item[key])) {
+			this.startCrop(selection[0]);
+			this.crop.box = { ...crop.box };
+			this.paintCrop();
+		}
 	}
 
 	place(item, change = { x: 0, y: 0, scale: 1 }) {
@@ -208,9 +235,19 @@ export class CanvasEditor {
 			left: `${(item.x + change.x) * PX_PER_MM}px`, top: `${(item.y + change.y) * PX_PER_MM}px`,
 			width: `${item.width * change.scale * PX_PER_MM}px`, height: `${item.height * change.scale * PX_PER_MM}px`,
 		});
+		if (item.textFrame) {
+			const { matrix: [a, b, c, d, e, f], width, height } = item.textFrame;
+			for (const handle of item.node.children) {
+				if (handle.dataset.corner !== "w" && handle.dataset.corner !== "e") continue;
+				const x = handle.dataset.corner === "e" ? width : 0;
+				handle.style.left = `${(a * x + c * height / 2 + e - item.x) * change.scale * PX_PER_MM}px`;
+				handle.style.top = `${(b * x + d * height / 2 + f - item.y) * change.scale * PX_PER_MM}px`;
+				handle.style.cursor = a === 0 ? "var(--resize-vertical, ns-resize)" : "var(--resize-horizontal, ew-resize)";
+			}
+		}
 	}
 
-	// placeShape positions basic-shape handles at their geometry rather than the padded boundary.
+	// placeShape 按图形几何范围放置手柄，不包含边界留量。
 	placeShape(item, box) {
 		const x = Math.min(box.x, box.x + box.width), y = Math.min(box.y, box.y + box.height);
 		Object.assign(item.node.style, {
@@ -226,13 +263,14 @@ export class CanvasEditor {
 		}
 	}
 
-	// items returns the current selection without treating a group as a document object.
+	// items 获取选中的真实对象，临时多选框不作为文档对象。
 	items() {
 		return this.selected?.items || (this.selected ? [this.selected] : []);
 	}
 
-	// setSelection updates object highlights and exposes one same-page selection to the toolbar.
+	// setSelection 更新同页对象选区，并同步工具栏。
 	setSelection(items) {
+		if (this.crop && (items.length !== 1 || items[0] !== this.crop.item)) this.closeCrop();
 		if (this.selected?.items) this.selected.node.remove();
 		for (const item of this.items()) {
 			item.node.classList.remove("selected", "multi-selected");
@@ -273,6 +311,7 @@ export class CanvasEditor {
 
 	clear() {
 		this.closeText();
+		this.closeCrop();
 		this.cancel();
 		this.pendingSelection = null;
 		this.select(null);
@@ -286,6 +325,19 @@ export class CanvasEditor {
 		if (!this.enabled || this.options.busy() || event.button !== 0 || this.drag) {
 			return;
 		}
+		if (this.crop) {
+			if (!event.target.closest(".edit-crop")) {
+				this.commitCrop();
+				return;
+			}
+			event.preventDefault();
+			this.viewer.focus({ preventScroll: true });
+			const { item, box } = this.crop;
+			this.drag = { crop: true, box: { ...box }, pointerID: event.pointerId, corner: event.target.dataset.corner || "",
+				page: item.page, rect: item.surface.getBoundingClientRect(), rotation: this.options.rotation(), clientX: event.clientX, clientY: event.clientY };
+			this.viewer.setPointerCapture(event.pointerId);
+			return;
+		}
 		if (this.tool) {
 			this.startShape(event);
 			return;
@@ -336,6 +388,13 @@ export class CanvasEditor {
 		}
 		event.preventDefault();
 		drag.pointer = event;
+		if (drag.crop) {
+			const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.page, drag.rotation);
+			const to = pagePoint(event.clientX, event.clientY, drag.rect, drag.page, drag.rotation);
+			this.crop.box = cropBox(drag.box, this.crop.item, to.x - from.x, to.y - from.y, drag.corner);
+			this.paintCrop();
+			return;
+		}
 		if (drag.shape) {
 			this.moveShape(event, drag);
 			return;
@@ -350,6 +409,16 @@ export class CanvasEditor {
 		const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.item.page, drag.rotation);
 		const to = pagePoint(event.clientX, event.clientY, drag.rect, drag.item.page, drag.rotation);
 		if (drag.item.type === "TextObject" && (drag.corner === "w" || drag.corner === "e")) {
+			if (drag.item.textFrame) {
+				const frame = drag.item.textFrame, [a, b, c, d] = frame.matrix;
+				const dx = (d * (to.x - from.x) - c * (to.y - from.y)) / (a * d - b * c);
+				const box = reshapeBox({ geometry: { x: 0, y: 0, width: frame.width, height: frame.height } }, dx, 0, drag.corner, false);
+				drag.box = { x: drag.item.x + box.x, width: box.width };
+				const bounds = transformedBox(box, frame.matrix);
+				Object.assign(drag.item.node.style, { left: `${bounds.x * PX_PER_MM}px`, top: `${bounds.y * PX_PER_MM}px`,
+					width: `${bounds.width * PX_PER_MM}px`, height: `${bounds.height * PX_PER_MM}px` });
+				return;
+			}
 			drag.box = reshapeBox({ geometry: drag.item }, to.x - from.x, 0, drag.corner, false);
 			Object.assign(drag.item.node.style, { left: `${drag.box.x * PX_PER_MM}px`, width: `${drag.box.width * PX_PER_MM}px` });
 			return;
@@ -365,7 +434,7 @@ export class CanvasEditor {
 		if (!drag.corner) this.showGuides(drag);
 	}
 
-	// showGuides keeps the visual threshold constant through page zoom and rotation.
+	// showGuides 在页面缩放和旋转时保持辅助线的屏幕判定距离一致。
 	showGuides(drag) {
 		const { item, rect, rotation, change } = drag;
 		const path = alignmentGuides({ ...item, x: item.x + change.x, y: item.y + change.y }, drag.targets, {
@@ -388,6 +457,11 @@ export class CanvasEditor {
 			return;
 		}
 		this.move(event);
+		if (drag.crop) {
+			this.drag = null;
+			this.viewer.releasePointerCapture(drag.pointerID);
+			return;
+		}
 		if (drag.marquee) {
 			this.drag = null;
 			drag.preview.remove();
@@ -419,7 +493,7 @@ export class CanvasEditor {
 		if ((drag.item.shape || drag.item.type === "TextObject") && drag.corner && drag.box) {
 			this.drag = null;
 			this.viewer.releasePointerCapture(drag.pointerID);
-			const geometry = drag.item.geometry || drag.item;
+			const geometry = drag.item.geometry || (drag.item.textFrame ? { x: drag.item.x, width: drag.item.textFrame.width } : drag.item);
 			const changed = Object.keys(drag.box).some((key) => drag.box[key] !== geometry[key]);
 			const apply = drag.item.shape ? this.options.onReshape : this.options.onTextWidth;
 			Promise.resolve(changed && apply(drag.item, drag.box)).finally(() => {
@@ -438,6 +512,10 @@ export class CanvasEditor {
 		const drag = this.drag;
 		this.drag = null;
 		if (drag) {
+			if (drag.crop) {
+				this.crop.box = drag.box;
+				this.paintCrop();
+			}
 			drag.preview?.remove();
 			drag.guides?.preview.remove();
 			if (drag.marquee) this.setSelection(drag.before);
@@ -450,7 +528,7 @@ export class CanvasEditor {
 		}
 	}
 
-	// startMarquee selects by page-space geometry, so rotation and zoom use the same hit tests.
+	// startMarquee 在页面坐标中开始框选，统一处理缩放和旋转。
 	startMarquee(event, additive) {
 		const surface = event.target.closest(".page-surface"), page = this.pages.get(surface);
 		if (!page) {
@@ -468,7 +546,7 @@ export class CanvasEditor {
 		this.viewer.setPointerCapture(event.pointerId);
 	}
 
-	// moveMarquee includes intersecting objects while preserving an additive selection.
+	// moveMarquee 选中与框选区域相交的对象，支持追加到已有选区。
 	moveMarquee(event, drag) {
 		const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.page, drag.rotation);
 		const to = pagePoint(event.clientX, event.clientY, drag.rect, drag.page, drag.rotation);
@@ -505,7 +583,7 @@ export class CanvasEditor {
 		this.viewer.setPointerCapture(event.pointerId);
 	}
 
-	// nearestSurface assigns a pasteboard gesture to one mounted page for its entire duration.
+	// nearestSurface 为页面外开始的手势确定一个已加载页面，拖动期间不切换页面。
 	nearestSurface(event) {
 		let nearest = null, distance = Infinity;
 		for (const surface of this.viewer.querySelectorAll(".page-surface")) {
@@ -521,7 +599,7 @@ export class CanvasEditor {
 		return nearest;
 	}
 
-	// createPreview provides a temporary SVG overlay without rerendering the page during a drag.
+	// createPreview 创建临时SVG预览层，拖动期间不重新渲染页面。
 	createPreview(surface, page, shape, style) {
 		const preview = document.createElementNS("http://www.w3.org/2000/svg", "svg");
 		preview.classList.add("edit-preview");
@@ -553,7 +631,7 @@ export class CanvasEditor {
 			? { x: from.x, y: from.y, width: to.x - from.x, height: to.y - from.y } : { x, y, width, height });
 	}
 
-	// modifierChange refreshes the preview even when Shift changes without pointer movement.
+	// modifierChange 在指针静止时响应Shift变化并刷新预览。
 	modifierChange(event) {
 		const pointer = this.drag?.pointer;
 		if (event.key === "Shift" && pointer) {
@@ -564,6 +642,16 @@ export class CanvasEditor {
 
 	keyDown(event) {
 		if (event.defaultPrevented || event.target?.closest("input, textarea, select, [contenteditable]")) return;
+		if (this.crop && !this.options.busy()) {
+			if (event.key === "Escape" || event.key === "Enter") {
+				event.preventDefault();
+				event.stopPropagation();
+				if (event.key === "Enter") this.commitCrop();
+				else if (this.drag) this.cancel();
+				else this.closeCrop();
+			}
+			return;
+		}
 		this.modifierChange(event);
 		if (event.key === "Escape" && this.drag && !this.tool && !this.options.busy()) {
 			event.preventDefault();
@@ -620,6 +708,11 @@ export class CanvasEditor {
 			lineHeight: item.paragraphHeight || item.lineHeight ? `${(item.paragraphHeight || item.lineHeight) * PX_PER_MM}px` : "normal", color: item.color,
 			textAlign: item.align || "left",
 		});
+		if (item.textFrame) {
+			const { width, height, matrix: [a, b, c, d, e, f] } = item.textFrame;
+			Object.assign(input.style, { left: "0px", top: "0px", width: `${Math.max(width, item.wrap ? width : 50) * PX_PER_MM + 4}px`,
+				minHeight: `${height * PX_PER_MM + 4}px`, transform: `matrix(${a},${b},${c},${d},${e * PX_PER_MM},${f * PX_PER_MM})` });
+		}
 		this.input = { input, item, face, fontChoice: item.fontChoice };
 		item.surface.append(input);
 		input.addEventListener("input", () => {
@@ -648,14 +741,14 @@ export class CanvasEditor {
 		if (!item.draft) input.select();
 	}
 
-	// resizeText follows the draft's current font and content without changing document geometry.
+	// resizeText 按当前字体和内容调整输入框，不修改文档中的几何范围。
 	resizeText() {
 		const { input } = this.input;
 		input.style.height = "0px";
 		input.style.height = `${input.scrollHeight + 2}px`;
 	}
 
-	// setTextFont changes only the inline buffer until text and font are committed together.
+	// setTextFont 暂存输入框字体，后续与文字内容一起提交。
 	setTextFont(face, data) {
 		const editing = this.input;
 		document.fonts.add(face);
@@ -700,4 +793,67 @@ export class CanvasEditor {
 			this.options.onTextChange();
 		}
 	}
+
+	// startCrop 开始调整图片保留区域，确认前不修改文档。
+	startCrop(item) {
+		this.cancel();
+		this.closeCrop();
+		this.setTool("");
+		const box = { x: item.x, y: item.y, width: item.width, height: item.height };
+		const { preview, node: mask } = this.createPreview(item.surface, item.page, "path", { fill: true, fillColor: "rgba(255,255,255,0.72)" });
+		mask.setAttribute("fill-rule", "evenodd");
+		const node = document.createElement("div");
+		node.className = "edit-layer edit-crop";
+		for (const corner of ["nw", "n", "ne", "e", "se", "s", "sw", "w"]) {
+			const handle = document.createElement("span");
+			handle.className = `edit-handle edit-${corner}`;
+			handle.dataset.corner = corner;
+			node.append(handle);
+		}
+		item.surface.append(node);
+		item.surface.classList.add("cropping");
+		this.crop = { item, box, node, mask, preview };
+		this.paintCrop();
+		this.viewer.focus({ preventScroll: true });
+	}
+
+	// paintCrop 更新遮罩及手柄，不重新渲染或复制图片数据。
+	paintCrop() {
+		const { item, box, node, mask } = this.crop;
+		const rectangle = b => `M${b.x} ${b.y}h${b.width}v${b.height}h${-b.width}Z`;
+		mask.setAttribute("d", rectangle(item) + rectangle(box));
+		Object.assign(node.style, { left: `${box.x * PX_PER_MM}px`, top: `${box.y * PX_PER_MM}px`, width: `${box.width * PX_PER_MM}px`, height: `${box.height * PX_PER_MM}px` });
+		this.options.onCropChange();
+	}
+
+	// cropChanged 判断裁剪范围是否有待提交的变更。
+	cropChanged() {
+		return Boolean(this.crop && ["x", "y", "width", "height"].some(key => this.crop.box[key] !== this.crop.item[key]));
+	}
+
+	// commitCrop 将裁剪作为一次可撤销操作提交，失败时保留预览。
+	async commitCrop() {
+		if (!this.crop) return true;
+		if (this.options.busy()) return false;
+		if (!this.cropChanged()) {
+			this.closeCrop();
+			return true;
+		}
+		const crop = this.crop;
+		const saved = await this.options.onCrop(crop.item, crop.box);
+		if (saved && this.crop === crop) this.closeCrop();
+		return Boolean(saved);
+	}
+
+	// closeCrop 移除临时裁剪区域，不修改文档内容。
+	closeCrop() {
+		if (!this.crop) return;
+		if (this.drag?.crop) this.cancel();
+		const crop = this.crop;
+		this.crop = null;
+		crop.node.remove();
+		crop.preview.remove();
+		crop.item.surface.classList.remove("cropping");
+		this.options.onCropChange();
+	}
 }

internal/webui/wasm.go

@@ -116,6 +116,9 @@ func RunWASM() {
 	registerCallback("ofdgoCopyObjects", copyObjects)
 	registerCallback("ofdgoOrderObjects", orderObjects)
 	registerCallback("ofdgoDistributeObjects", distributeObjects)
+	registerCallback("ofdgoRotateObjects", rotateObjects)
+	registerCallback("ofdgoFlipObjects", flipObjects)
+	registerCallback("ofdgoCropImage", cropImage)
 	registerCallback("ofdgoDeleteObject", deleteObject)
 	registerCallback("ofdgoUndo", func([]js.Value) (any, error) { return restoreEditor(false) })
 	registerCallback("ofdgoRedo", func([]js.Value) (any, error) { return restoreEditor(true) })
@@ -572,7 +575,7 @@ func restoreEditor(redo bool) (any, error) {
 	return previewEditor(currentEditor, currentSession.Renderer.RenderAnnotations)
 }
 
-// editorObjects 提供创作画布的对象命中区域
+// editorObjects 提供创作画布的对象范围、文字排版及原始图片边界
 // 入参: index 页面索引, text 页面文字
 // 返回: []any 对象区域, error 错误信息
 func editorObjects(index int, text *ofdgo.PageText) ([]any, error) {
@@ -632,6 +635,13 @@ func editorObjects(index int, text *ofdgo.PageText) ([]any, error) {
 			}
 			if box.W > 0 && box.H > 0 {
 				item := map[string]any{"id": id, "type": object.Type, "x": box.X, "y": box.Y, "width": box.W, "height": box.H, "order": order, "count": len(layer.Objects)}
+				if object.Type == "ImageObject" {
+					full, err := object.ImageObject.ImageBounds()
+					if err != nil {
+						return nil, err
+					}
+					item["imageBounds"] = editorBox(full)
+				}
 				if object.Type == "PathObject" {
 					path := object.PathObject
 					kind, geometry := path.Shape()
@@ -652,12 +662,23 @@ func editorObjects(index int, text *ofdgo.PageText) ([]any, error) {
 					value, layout := source.TextObject.TextLayout()
 					item["text"], item["font"], item["fontName"], item["size"] = value, object.TextObject.Font, fontNames[object.TextObject.Font], object.TextObject.Size
 					item["wrap"], item["align"], item["paragraphHeight"] = layout.Wrap, layout.Align, layout.LineHeight
+					frame, err := object.TextObject.TextFrame()
+					if err != nil {
+						return nil, err
+					}
+					boundary, _ := ofdgo.ParseBox(object.TextObject.Boundary)
+					matrix := ofdgo.TranslationMatrix(boundary.X, boundary.Y).Multiply(ofdgo.NewMatrix(object.TextObject.CTM))
+					inverse, _ := matrix.Invert()
+					local := inverse.TransformBox(box)
+					width := math.Max(object.TextObject.Size, local.X+local.W)
 					if layout.Wrap {
-						frame, err := ofdgo.ParseBox(object.TextObject.Boundary)
+						width = frame.W
-						if err != nil {
+					}
-							return nil, err
+					frame = ofdgo.Box{W: width, H: math.Max(object.TextObject.Size, local.Y+local.H)}
-						}
+					item["textFrame"] = map[string]any{"width": frame.W, "height": frame.H, "matrix": editorMatrix(matrix)}
-						item["x"], item["y"], item["width"], item["height"] = frame.X, frame.Y, frame.W, math.Max(object.TextObject.Size, box.Y+box.H-frame.Y)
+					if layout.Wrap {
+						bounds := matrix.TransformBox(frame)
+						item["x"], item["y"], item["width"], item["height"] = bounds.X, bounds.Y, bounds.W, bounds.H
 					}
 					if codes := object.TextObject.TextCode; len(codes) > 1 {
 						first, _ := strconv.ParseFloat(codes[0].Y, 64)
@@ -815,6 +836,8 @@ func orderObjects(args []js.Value) (any, error) {
 }
 
 // distributeObjects 按指定轴等距分布选区。
+// 入参: args 页面索引、对象标识数组和分布轴
+// 返回: any 文档信息, error 错误信息
 func distributeObjects(args []js.Value) (any, error) {
 	return changeObjects(func() error {
 		return currentEditor.DistributeObjects(args[0].Int(), stringsFromJS(args[1]), args[2].String())
@@ -1129,7 +1152,7 @@ func insertText(args []js.Value) (any, error) {
 }
 
 // layoutText 调整文字框和段落排版，保留软换行前的原文。
-// 入参: args 页码、对象标识、左侧坐标、宽度、折行、对齐和行距
+// 入参: args 页码、对象标识、本地左侧偏移、宽度、折行、对齐和行距
 // 返回: any 文档信息, error 错误信息
 func layoutText(args []js.Value) (any, error) {
 	if currentEditor == nil {
@@ -1143,14 +1166,12 @@ func layoutText(args []js.Value) (any, error) {
 	if object.Type != "TextObject" {
 		return nil, fmt.Errorf("object is not text")
 	}
-	box, err := ofdgo.ParseBox(object.TextObject.Boundary)
-	if err != nil {
-		return nil, err
-	}
 	if !args[2].IsNull() {
-		box.X, box.W = args[2].Float(), args[3].Float()
+		object.TextObject, err = object.TextObject.ResizeTextFrame(args[2].Float(), args[3].Float())
+		if err != nil {
+			return nil, err
+		}
 	}
-	object.TextObject.Boundary = fmt.Sprintf("%g %g %g %g", box.X, box.Y, box.W, box.H)
 	value, _ := object.TextObject.TextLayout()
 	if err := currentEditor.LayoutText(&object.TextObject, value, ofdgo.TextLayout{Wrap: args[4].Bool(), Align: args[5].String(), LineHeight: args[6].Float()}); err != nil {
 		return nil, err
@@ -1165,7 +1186,53 @@ func layoutText(args []js.Value) (any, error) {
 	return previewEditor(currentEditor, currentSession.Renderer.RenderAnnotations)
 }
 
+// editorBox 将库层毫米边界传递给画布交互层。
+// 入参: box 毫米坐标中的矩形范围
+// 返回: map[string]any 可直接传递给JavaScript的横纵坐标和宽高
+func editorBox(box ofdgo.Box) map[string]any {
+	return map[string]any{"x": box.X, "y": box.Y, "width": box.W, "height": box.H}
+}
+
+// editorMatrix 将标准CTM转换为浏览器仿射矩阵分量。
+// 入参: matrix 库层仿射矩阵
+// 返回: []any 可直接传递给JavaScript的a、b、c、d、e、f分量，位移单位为毫米
+func editorMatrix(matrix ofdgo.Matrix) []any {
+	x, y := matrix.Transform(0, 0)
+	ax, ay := matrix.Transform(1, 0)
+	bx, by := matrix.Transform(0, 1)
+	return []any{ax - x, ay - y, bx - x, by - y, x, y}
+}
+
+// rotateObjects 旋转同页选区，通用几何与历史记录由库负责。
+// 入参: args 页面索引、对象标识数组和顺时针角度
+// 返回: any 文档信息, error 错误信息
+func rotateObjects(args []js.Value) (any, error) {
+	return changeObjects(func() error {
+		return currentEditor.RotateObjects(args[0].Int(), stringsFromJS(args[1]), args[2].Int())
+	})
+}
+
+// flipObjects 镜像同页选区。
+// 入参: args 页面索引、对象标识数组和镜像轴
+// 返回: any 文档信息, error 错误信息
+func flipObjects(args []js.Value) (any, error) {
+	return changeObjects(func() error {
+		return currentEditor.FlipObjects(args[0].Int(), stringsFromJS(args[1]), args[2].String())
+	})
+}
+
+// cropImage 设置图片裁剪范围，保留原始图片数据。
+// 入参: args 页面索引、对象标识及页面毫米坐标中的横纵坐标和宽高
+// 返回: any 文档信息, error 错误信息
+func cropImage(args []js.Value) (any, error) {
+	return changeObjects(func() error {
+		return currentEditor.CropImage(args[0].Int(), args[1].String(), ofdgo.Box{X: args[2].Float(), Y: args[3].Float(), W: args[4].Float(), H: args[5].Float()})
+	})
+}
+
 // transformObjects 统一移动或缩放选区，生成一次撤销记录。
+// 入参: args 页面索引、对象标识数组、横纵位移和正缩放比例
+// 返回: any 文档信息, error 错误信息
 func transformObjects(args []js.Value) (any, error) {
 	return changeObjects(func() error {
 		return currentEditor.TransformObjects(args[0].Int(), stringsFromJS(args[1]), args[2].Float(), args[3].Float(), args[4].Float())
@@ -1173,6 +1240,8 @@ func transformObjects(args []js.Value) (any, error) {
 }
 
 // alignObjects 对齐选区中的对象。
+// 入参: args 页面索引、对象标识数组和对齐方式
+// 返回: any 文档信息, error 错误信息
 func alignObjects(args []js.Value) (any, error) {
 	return changeObjects(func() error {
 		return currentEditor.AlignObjects(args[0].Int(), stringsFromJS(args[1]), args[2].String())
@@ -1180,6 +1249,8 @@ func alignObjects(args []js.Value) (any, error) {
 }
 
 // deleteObjects 一次删除选区中的对象。
+// 入参: args 页面索引和对象标识数组
+// 返回: any 文档信息, error 错误信息
 func deleteObjects(args []js.Value) (any, error) {
 	return changeObjects(func() error {
 		return currentEditor.DeleteObjects(args[0].Int(), stringsFromJS(args[1]))
@@ -1187,6 +1258,8 @@ func deleteObjects(args []js.Value) (any, error) {
 }
 
 // changeObjects 提交库层批量操作，无修改时复用当前预览。
+// 入参: apply 待执行的编辑操作
+// 返回: any 文档信息, error 错误信息
 func changeObjects(apply func() error) (any, error) {
 	if currentEditor == nil {
 		return nil, fmt.Errorf("no document is being created")

ofdgo_editor.go

@@ -352,7 +352,7 @@ func (e *Editor) AddImage(data []byte) (string, error) {
 }
 
 // AddObject 按添加顺序放入正文图层，支持文字、路径和图片，自动分配对象ID
-// 首版支持基本颜色和直接资源引用，不支持动作、裁剪、渐变及复合图元
+// 支持基本颜色、直接资源引用及图片的路径裁剪，不支持动作、渐变及复合图元
 // 入参: page 页面索引, object 对象内容，添加后不再引用调用方的可变数据
 // 返回: string 对象标识, error 错误信息
 func (e *Editor) AddObject(page int, object GraphicObject) (string, error) {
@@ -577,8 +577,11 @@ func (e *Editor) prepareObject(id string, object GraphicObject) (GraphicObject,
 	} else if object.Type == "ImageObject" {
 		object.ImageObject.CTM = fmt.Sprintf("%s 0 0 %s 0 0", ofdNumber(box.W), ofdNumber(box.H))
 	}
-	if drawParam != "" || clips != nil || len(actions) != 0 {
+	if drawParam != "" || len(actions) != 0 || clips != nil && object.Type != "ImageObject" {
-		return GraphicObject{}, fmt.Errorf("draw parameter references, clips and actions are not supported for creation")
+		return GraphicObject{}, fmt.Errorf("draw parameter references, non-image clips and actions are not supported for creation")
+	}
+	if err := e.validateImageClips(clips); err != nil {
+		return GraphicObject{}, err
 	}
 	if alpha != nil && (*alpha < 0 || *alpha > 255) {
 		return GraphicObject{}, fmt.Errorf("alpha must be between 0 and 255")
@@ -594,6 +597,42 @@ func (e *Editor) prepareObject(id string, object GraphicObject) (GraphicObject,
 	return cloneEditorObject(object)
 }
 
+// validateImageClips 校验图片的路径裁剪，仅接受无资源引用及嵌套裁剪的路径
+// 入参: clips 图片裁剪集合，nil表示无裁剪
+// 返回: error 错误信息
+func (e *Editor) validateImageClips(clips *Clips) error {
+	if clips == nil {
+		return nil
+	}
+	if len(clips.Clip) == 0 {
+		return fmt.Errorf("image clips must contain a clip")
+	}
+	for _, clip := range clips.Clip {
+		if len(clip.Area) == 0 {
+			return fmt.Errorf("image clip must contain an area")
+		}
+		for _, area := range clip.Area {
+			if len(area.Path) == 0 || area.DrawParam != "" || len(area.Text) != 0 {
+				return fmt.Errorf("image clips only support paths without draw parameter references")
+			}
+			if area.CTM != "" {
+				if _, err := creationNumbers(area.CTM, 6); err != nil {
+					return err
+				}
+			}
+			for _, path := range area.Path {
+				if path.ID != "" {
+					return fmt.Errorf("clip paths must not have object IDs")
+				}
+				if _, err := e.prepareObject("", GraphicObject{Type: "PathObject", PathObject: path}); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
 // cloneEditorObject 通过统一序列化规则复制对象
 // 入参: object 对象内容
 // 返回: GraphicObject 独立副本, error 错误信息
@@ -668,6 +707,8 @@ func (e *Editor) TransformObject(page int, id string, dx, dy, scale float64) err
 }
 
 // transformEditorObject 变换独立对象副本，保留绘制属性和编辑中的段落信息。
+// 入参: object 对象副本, dx 横向位移, dy 纵向位移, scale 正缩放比例
+// 返回: GraphicObject 变换后的对象, error 错误信息
 func transformEditorObject(object GraphicObject, dx, dy, scale float64) (GraphicObject, error) {
 	var boundary, ctm *string
 	switch object.Type {
@@ -696,6 +737,9 @@ func transformEditorObject(object GraphicObject, dx, dy, scale float64) (Graphic
 		boundary, ctm = &object.PathObject.Boundary, &object.PathObject.CTM
 	case "ImageObject":
 		boundary, ctm = &object.ImageObject.Boundary, &object.ImageObject.CTM
+		if scale != 1 {
+			object.ImageObject.Clips = transformImageClips(object.ImageObject.Clips, Matrix{a: scale, d: scale})
+		}
 	}
 	box, err := ParseBox(*boundary)
 	if err != nil {
@@ -780,7 +824,7 @@ func (e *Editor) LayoutText(obj *TextObject, value string, options TextLayout) e
 	}
 	var width float64
 	if options.Wrap || options.Align != "" && options.Align != "left" {
-		box, err := creationBox(obj.Boundary)
+		box, err := obj.TextFrame()
 		if err != nil {
 			return err
 		}

ofdgo_editor_batch.go

@@ -175,6 +175,7 @@ func (e *Editor) DistributeObjects(page int, ids []string, axis string) error {
 }
 
 // replaceObjects 替换正文对象列表，隔离历史快照与后续的增删、排序操作。
+// 入参: page 页面索引, objects 新的正文对象列表
 func (e *Editor) replaceObjects(page int, objects []GraphicObject) {
 	before := e.pages[page].Content.Layer[0].Objects
 	if reflect.DeepEqual(before, objects) {
@@ -319,6 +320,8 @@ func (e *Editor) DeleteObjects(page int, ids []string) error {
 }
 
 // selectedObjects 校验同页选择，返回内部只读对象与对应索引。
+// 入参: page 页面索引, ids 对象标识，不得重复
+// 返回: []GraphicObject 所选对象, []int 正文对象索引, error 错误信息
 func (e *Editor) selectedObjects(page int, ids []string) ([]GraphicObject, []int, error) {
 	if _, err := e.page(page); err != nil {
 		return nil, nil, err
@@ -341,6 +344,8 @@ func (e *Editor) selectedObjects(page int, ids []string) ([]GraphicObject, []int
 }
 
 // editorObjectID 获取可创作对象的标准标识。
+// 入参: object 图形对象
+// 返回: string 对象标识，不支持的类型返回空字符串
 func editorObjectID(object GraphicObject) string {
 	switch object.Type {
 	case "TextObject":
@@ -354,6 +359,8 @@ func editorObjectID(object GraphicObject) string {
 }
 
 // objectBounds 批量获取对齐范围，每页只度量一次文字。
+// 入参: page 页面索引, objects 待度量的对象
+// 返回: []Box 对象范围，文字采用字形范围，其余采用Boundary, error 错误信息
 func (e *Editor) objectBounds(page int, objects []GraphicObject) ([]Box, error) {
 	textBoxes := make(map[string]Box)
 	if slices.ContainsFunc(objects, func(o GraphicObject) bool { return o.Type == "TextObject" }) {

ofdgo_editor_text.go

@@ -20,7 +20,7 @@ import (
 	"github.com/go-text/typesetting/segmenter"
 )
 
-// TextLayout 横向段落选项，Wrap按Boundary宽度折行，Align为left、center、right或justify。
+// TextLayout 本地横向段落选项，Wrap按CTM变换前的边界宽度折行，Align为left、center、right或justify。
 // LineHeight为毫米单位的基线间距，0使用字体度量；零值保持显式换行和左对齐。
 type TextLayout struct {
 	Wrap       bool
@@ -45,6 +45,8 @@ func (obj TextObject) TextLayout() (string, TextLayout) {
 }
 
 // breakTextLines 优先使用Unicode断行机会，过长词仅在字素边界折行，不丢弃空白。
+// 入参: runes 段落字符, advances 各字符步进, width 本地排版宽度, wrap 是否自动折行
+// 返回: [][2]int 各行的字符起止索引，左闭右开
 func breakTextLines(runes []rune, advances []float64, width float64, wrap bool) [][2]int {
 	if !wrap || len(runes) == 0 {
 		return [][2]int{{0, len(runes)}}
@@ -99,6 +101,8 @@ func breakTextLines(runes []rune, advances []float64, width float64, wrap bool)
 }
 
 // alignTextLine 将段落对齐转换为标准X和DeltaX，两端对齐保留段落末行左对齐。
+// 入参: runes 行内字符, advances 各字符步进, width 本地排版宽度, alignment 对齐方式, justify 是否允许本行两端对齐
+// 返回: float64 行首X坐标, string 字符间的DeltaX序列
 func alignTextLine(runes []rune, advances []float64, width float64, alignment string, justify bool) (float64, string) {
 	end := len(runes)
 	for end > 0 && runes[end-1] == ' ' {

ofdgo_editor_transform.go

@@ -0,0 +1,237 @@
+// 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 (
+	"fmt"
+	"slices"
+)
+
+// RotateObject 绕对象中心旋转，文字采用字形范围，其余对象采用Boundary。
+// 入参: page 页面索引, id 对象标识, degrees 顺时针角度
+// 返回: error 错误信息
+func (e *Editor) RotateObject(page int, id string, degrees int) error {
+	return e.RotateObjects(page, []string{id}, degrees)
+}
+
+// RotateObjects 绕同页选区中心旋转，文字采用字形范围，其余对象采用Boundary。
+// 保留相对位置及资源，一次撤销恢复全部。
+// 入参: page 页面索引, ids 对象标识, degrees 顺时针角度，仅支持90度的整数倍
+// 返回: error 错误信息
+func (e *Editor) RotateObjects(page int, ids []string, degrees int) error {
+	if degrees%90 != 0 {
+		return fmt.Errorf("rotation must be a multiple of 90 degrees")
+	}
+	turn := (degrees%360 + 360) % 360 / 90
+	m := []Matrix{IdentityMatrix, {b: 1, c: -1}, {a: -1, d: -1}, {b: -1, c: 1}}[turn]
+	return e.orientObjects(page, ids, m)
+}
+
+// FlipObject 绕对象中心镜像，文字采用字形范围，其余对象采用Boundary。
+// 入参: page 页面索引, id 对象标识, axis 为horizontal或vertical
+// 返回: error 错误信息
+func (e *Editor) FlipObject(page int, id, axis string) error {
+	return e.FlipObjects(page, []string{id}, axis)
+}
+
+// FlipObjects 以同页选区中心镜像，保留资源及绘制顺序，一次撤销恢复全部。
+// 文字采用字形范围，其余对象采用Boundary。
+// 入参: page 页面索引, ids 对象标识, axis 为horizontal或vertical
+// 返回: error 错误信息
+func (e *Editor) FlipObjects(page int, ids []string, axis string) error {
+	m := IdentityMatrix
+	switch axis {
+	case "horizontal":
+		m.a = -1
+	case "vertical":
+		m.d = -1
+	default:
+		return fmt.Errorf("invalid flip axis %q", axis)
+	}
+	return e.orientObjects(page, ids, m)
+}
+
+// orientObjects 更新Boundary与CTM，不重排文字或重采样图片。
+// 入参: page 页面索引, ids 对象标识, matrix 直角旋转或镜像矩阵
+// 返回: error 错误信息
+func (e *Editor) orientObjects(page int, ids []string, matrix Matrix) error {
+	objects, _, err := e.selectedObjects(page, ids)
+	if err != nil || len(objects) == 0 || matrix == IdentityMatrix {
+		return err
+	}
+	boxes, err := e.objectBounds(page, objects)
+	if err != nil {
+		return err
+	}
+	var box Box
+	for _, item := range boxes {
+		box = unionTextBox(box, item)
+	}
+	x, y := box.X+box.W/2, box.Y+box.H/2
+	matrix = TranslationMatrix(x, y).Multiply(matrix).Multiply(TranslationMatrix(-x, -y))
+	for i, object := range objects {
+		var boundary, ctm *string
+		switch object.Type {
+		case "TextObject":
+			boundary, ctm = &object.TextObject.Boundary, &object.TextObject.CTM
+		case "PathObject":
+			boundary, ctm = &object.PathObject.Boundary, &object.PathObject.CTM
+		case "ImageObject":
+			boundary, ctm = &object.ImageObject.Boundary, &object.ImageObject.CTM
+		}
+		before, _ := ParseBox(*boundary)
+		after := matrix.TransformBox(before)
+		local := TranslationMatrix(-after.X, -after.Y).Multiply(matrix).Multiply(TranslationMatrix(before.X, before.Y))
+		*ctm = local.Multiply(NewMatrix(*ctm)).String()
+		*boundary = editorBoxString(after)
+		if object.Type == "ImageObject" {
+			object.ImageObject.Clips = transformImageClips(object.ImageObject.Clips, local)
+		}
+		objects[i] = object
+	}
+	return e.UpdateObjects(page, objects)
+}
+
+// transformImageClips 同步变换不随对象CTM变化的裁剪区域，不修改原始裁剪数据。
+// 入参: clips 图片裁剪集合, matrix 对象边界坐标中的变换
+// 返回: *Clips 变换后的裁剪集合
+func transformImageClips(clips *Clips, matrix Matrix) *Clips {
+	if clips == nil || clips.TransFlag == nil || *clips.TransFlag {
+		return clips
+	}
+	result := *clips
+	result.Clip = slices.Clone(clips.Clip)
+	for i := range result.Clip {
+		result.Clip[i].Area = slices.Clone(clips.Clip[i].Area)
+		for j := range result.Clip[i].Area {
+			area := &result.Clip[i].Area[j]
+			area.CTM = matrix.Multiply(NewMatrix(area.CTM)).String()
+		}
+	}
+	return &result
+}
+
+// ImageBounds 返回完整图片经Boundary位移及CTM变换后的轴对齐边界，不应用裁剪或父级变换。
+// 返回: Box 所在坐标系中的完整图片边界, error 错误信息
+func (obj ImageObject) ImageBounds() (Box, error) {
+	box, err := creationBox(obj.Boundary)
+	if err != nil {
+		return Box{}, err
+	}
+	if obj.CTM == "" {
+		return box, nil
+	}
+	if _, err := creationNumbers(obj.CTM, 6); err != nil {
+		return Box{}, err
+	}
+	return TranslationMatrix(box.X, box.Y).Multiply(NewMatrix(obj.CTM)).TransformBox(Box{W: 1, H: 1}), nil
+}
+
+// CropImage 按页面毫米坐标重设图片裁剪，保留原始资源及像素，可再次扩大裁剪区域。
+// 使用ImageObject.ImageBounds返回的范围可还原完整图片；提交一次撤销记录。
+// 入参: page 页面索引, id 图片对象标识, box 页面毫米坐标中的保留范围
+// 返回: error 错误信息
+func (e *Editor) CropImage(page int, id string, box Box) error {
+	object, err := e.Object(page, id)
+	if err != nil {
+		return err
+	}
+	if object.Type != "ImageObject" {
+		return fmt.Errorf("object %q is not an image", id)
+	}
+	image := &object.ImageObject
+	full, err := image.ImageBounds()
+	if err != nil {
+		return err
+	}
+	if _, err := creationBox(editorBoxString(box)); err != nil {
+		return err
+	}
+	if box.X < full.X-1e-9 || box.Y < full.Y-1e-9 || box.X+box.W > full.X+full.W+1e-9 || box.Y+box.H > full.Y+full.H+1e-9 {
+		return fmt.Errorf("crop must stay within the image bounds")
+	}
+	before, _ := ParseBox(image.Boundary)
+	if box.X != before.X || box.Y != before.Y {
+		image.CTM = TranslationMatrix(before.X-box.X, before.Y-box.Y).Multiply(NewMatrix(image.CTM)).String()
+	}
+	image.Boundary = editorBoxString(box)
+	image.Clips = nil
+	if box != full {
+		inverse, ok := NewMatrix(image.CTM).Invert()
+		if !ok {
+			return fmt.Errorf("image transform is not invertible")
+		}
+		path, err := NewShape(ShapeRectangle, Box{W: box.W, H: box.H})
+		if err != nil {
+			return err
+		}
+		fill, stroke := true, false
+		path.Fill, path.Stroke = &fill, &stroke
+		image.Clips = &Clips{Clip: []Clip{{Area: []ClipArea{{CTM: inverse.String(), Path: []PathObject{path}}}}}}
+	}
+	return e.UpdateObject(page, id, object)
+}
+
+// TextFrame 将对象Boundary逆变换到本地坐标并返回轴对齐边界。
+// 直角旋转与翻转不改变本地段落宽度。
+// 返回: Box 对象本地坐标中的边界, error 错误信息
+func (obj TextObject) TextFrame() (Box, error) {
+	box, err := creationBox(obj.Boundary)
+	if err != nil {
+		return Box{}, err
+	}
+	if obj.CTM != "" {
+		if _, err := creationNumbers(obj.CTM, 6); err != nil {
+			return Box{}, err
+		}
+	}
+	m, ok := NewMatrix(obj.CTM).Invert()
+	if !ok {
+		return Box{}, fmt.Errorf("text transform is not invertible")
+	}
+	return m.TransformBox(Box{W: box.W, H: box.H}), nil
+}
+
+// ResizeTextFrame 调整文字本地坐标的左侧偏移及宽度，保留页面方向；重新排版后通过UpdateObject提交。
+// 支持轴向缩放、直角旋转与镜像，不支持斜切或其他角度旋转。
+// 入参: offset 本地左侧位移, width 新的本地排版宽度，单位为毫米
+// 返回: TextObject 调整后的文字对象, error 错误信息
+func (obj TextObject) ResizeTextFrame(offset, width float64) (TextObject, error) {
+	frame, err := obj.TextFrame()
+	if err != nil {
+		return TextObject{}, err
+	}
+	if !axisAlignedMatrix(NewMatrix(obj.CTM)) {
+		return TextObject{}, fmt.Errorf("text frame resizing requires an axis-aligned transform")
+	}
+	if !finite(offset) || !finite(width) || width <= 0 {
+		return TextObject{}, fmt.Errorf("text frame requires a finite offset and a positive width")
+	}
+	boundary, _ := ParseBox(obj.Boundary)
+	m := TranslationMatrix(boundary.X, boundary.Y).Multiply(NewMatrix(obj.CTM))
+	frame.X += offset
+	frame.W = width
+	box := m.TransformBox(frame)
+	obj.CTM = TranslationMatrix(-box.X, -box.Y).Multiply(m).Multiply(TranslationMatrix(offset, 0)).String()
+	obj.Boundary = editorBoxString(box)
+	return obj, nil
+}
+
+// editorBoxString 使用统一精度序列化创作边界。
+// 入参: box 矩形范围
+// 返回: string 标准Boundary属性值
+func editorBoxString(box Box) string {
+	return fmt.Sprintf("%s %s %s %s", ofdNumber(box.X), ofdNumber(box.Y), ofdNumber(box.W), ofdNumber(box.H))
+}

ofdgo_font_fs.go

@@ -584,8 +584,9 @@ func (d *fontDir) Stat() (fs.FileInfo, error) {
 	return fontFileInfo{name: ".", mode: fs.ModeDir}, nil
 }
 
-// Read 读取字体目录数据
+// Read 字体目录不提供字节内容，始终返回EOF
-// 返回: int 读取字节数, error 错误信息
+// 入参: []byte 读取缓冲区，不使用
+// 返回: int 始终为0, error 始终为io.EOF
 func (d *fontDir) Read([]byte) (int, error) {
 	return 0, io.EOF
 }

ofdgo_font_ttf.go

@@ -192,7 +192,9 @@ func fixTrueType(data []byte, fixCmap, fixName bool) (bool, []byte, map[rune]uin
 	return true, finalData, mapping, missingCmap, nil
 }
 
-// hasBadPostTable 检查post表是否会被canvas/font拒绝
+// hasBadPostTable 检查post表的版本、长度及字形数量是否存在已知不兼容
+// 入参: data post表数据, numGlyphs 字形总数, isTrueType 是否使用TrueType轮廓
+// 返回: bool 是否需要替换post表
 func hasBadPostTable(data []byte, numGlyphs uint16, isTrueType bool) bool {
 	if len(data) < 32 {
 		return true

ofdgo_font_util.go

@@ -537,7 +537,9 @@ func buildCmapTable(numGlyphs uint16, mapping map[rune]uint16) []byte {
 	return mainBuf.Bytes()
 }
 
-// shouldBuildCmapFormat12 判断format 4是否会溢出16位length
+// shouldBuildCmapFormat12 判断字符超出BMP或format 4长度溢出时是否需要format 12
+// 入参: mapping 字符到字形的映射
+// 返回: bool 是否需要构建format 12子表
 func shouldBuildCmapFormat12(mapping map[rune]uint16) bool {
 	if mapping == nil {
 		return false

ofdgo_geom.go

@@ -96,6 +96,39 @@ func (m Matrix) Transform(x, y float64) (float64, float64) {
 	return nx, ny
 }
 
+// TransformBox 获取矩形经仿射变换后的轴对齐边界。
+// 入参: box 原始矩形范围
+// 返回: Box 变换后的轴对齐边界
+func (m Matrix) TransformBox(box Box) Box {
+	x, y := m.Transform(box.X, box.Y)
+	left, top, right, bottom := x, y, x, y
+	for _, point := range [][2]float64{{box.X + box.W, box.Y}, {box.X, box.Y + box.H}, {box.X + box.W, box.Y + box.H}} {
+		x, y := m.Transform(point[0], point[1])
+		left, top, right, bottom = math.Min(left, x), math.Min(top, y), math.Max(right, x), math.Max(bottom, y)
+	}
+	return Box{X: left, Y: top, W: right - left, H: bottom - top}
+}
+
+// String 返回标准CTM属性值。
+// 返回: string 六个空格分隔的矩阵分量
+func (m Matrix) String() string {
+	return fmt.Sprintf("%s %s %s %s %s %s", ofdNumber(m.a), ofdNumber(m.b), ofdNumber(m.c), ofdNumber(m.d), ofdNumber(m.e), ofdNumber(m.f))
+}
+
+// axisAlignedMatrix 判断变换是否保持坐标轴平行，含直角旋转与镜像。
+// 入参: m 仿射变换矩阵
+// 返回: bool 是否为非退化的轴对齐变换
+func axisAlignedMatrix(m Matrix) bool {
+	return m.b == 0 && m.c == 0 && m.a != 0 && m.d != 0 || m.a == 0 && m.d == 0 && m.b != 0 && m.c != 0
+}
+
+// matrixVector 变换位移，不包含平移分量。
+// 入参: m 仿射变换矩阵, x、y 原始位移
+// 返回: float64 变换后的X位移, float64 变换后的Y位移
+func matrixVector(m Matrix, x, y float64) (float64, float64) {
+	return m.a*x + m.c*y, m.b*x + m.d*y
+}
+
 // Invert 求逆矩阵
 // 返回: Matrix 逆矩阵, bool 是否可逆
 func (m Matrix) Invert() (Matrix, bool) {

ofdgo_shape.go

@@ -65,7 +65,7 @@ func NewShape(kind ShapeKind, box Box) (PathObject, error) {
 	return object, nil
 }
 
-// Shape 识别 NewShape 生成的基本路径及其正向轴对齐缩放、平移，返回应用 Boundary 和 CTM 后的几何范围。
+// Shape 识别 NewShape 生成的基本路径及其轴对齐缩放、直角旋转、镜像和平移。
 // 直线范围以起点和有符号的端点位移表示；非基本路径或不支持的变换返回空类型。
 // 返回: ShapeKind 图形类型, Box 几何范围（不含描边）
 func (p PathObject) Shape() (ShapeKind, Box) {
@@ -110,11 +110,16 @@ func (p PathObject) Shape() (ShapeKind, Box) {
 	}
 	boundary, err := ParseBox(p.Boundary)
 	m := NewMatrix(p.CTM)
-	if err != nil || m.a <= 0 || m.d <= 0 || m.b != 0 || m.c != 0 {
+	if err != nil || !axisAlignedMatrix(m) {
 		return "", Box{}
 	}
-	x, y := m.Transform(box.X, box.Y)
+	if kind == ShapeLine {
-	box = Box{X: boundary.X + x, Y: boundary.Y + y, W: box.W * m.a, H: box.H * m.d}
+		x, y := m.Transform(box.X, box.Y)
+		w, h := matrixVector(m, box.W, box.H)
+		box = Box{X: boundary.X + x, Y: boundary.Y + y, W: w, H: h}
+	} else {
+		box = TranslationMatrix(boundary.X, boundary.Y).Multiply(m).TransformBox(box)
+	}
 	if !finite(box.X) || !finite(box.Y) || !finite(box.W) || !finite(box.H) || !finite(box.X+box.W) || !finite(box.Y+box.H) {
 		return "", Box{}
 	}
@@ -141,7 +146,7 @@ func sameShapePath(a, b []string) bool {
 	return true
 }
 
-// Reshape 调整基本路径在所在坐标系中的几何范围，保留对象标识、变换和绘制属性，不缩放线宽。
+// Reshape 调整基本路径在所在坐标系中的几何范围，保留对象标识、方向、缩放和绘制属性，不缩放线宽。
 // 返回对象可通过 Editor.UpdateObject 写入；仅支持 Shape 可识别的路径。
 // 入参: box 新几何范围，直线使用起点和有符号的端点位移
 // 返回: PathObject 调整后的对象, error 错误信息
@@ -157,12 +162,36 @@ func (p PathObject) Reshape(box Box) (PathObject, error) {
 		return PathObject{}, fmt.Errorf("shape coordinates must be finite")
 	}
 	m := NewMatrix(p.CTM)
-	shape, err := NewShape(kind, Box{W: box.W / m.a, H: box.H / m.d})
+	var w, h float64
+	if m.b == 0 {
+		w, h = box.W/m.a, box.H/m.d
+	} else {
+		w, h = box.H/m.b, box.W/m.c
+	}
+	if kind != ShapeLine {
+		w, h = math.Abs(w), math.Abs(h)
+	}
+	shape, err := NewShape(kind, Box{W: w, H: h})
 	if err != nil {
 		return PathObject{}, err
 	}
 	boundary, _ := ParseBox(shape.Boundary)
-	p.Boundary = fmt.Sprintf("%g %g %g %g", box.X+boundary.X*m.a-m.e, box.Y+boundary.Y*m.d-m.f, boundary.W*m.a, boundary.H*m.d)
+	if m.a > 0 && m.d > 0 && m.b == 0 && m.c == 0 {
+		p.Boundary = fmt.Sprintf("%g %g %g %g", box.X+boundary.X*m.a-m.e, box.Y+boundary.Y*m.d-m.f, boundary.W*m.a, boundary.H*m.d)
+	} else {
+		m.e, m.f = 0, 0
+		var x, y float64
+		if kind == ShapeLine {
+			x, y = m.Transform(-boundary.X, -boundary.Y)
+		} else {
+			bounds := m.TransformBox(boundary)
+			x, y = bounds.X, bounds.Y
+		}
+		m = TranslationMatrix(box.X-x, box.Y-y).Multiply(m)
+		bounds := m.TransformBox(Box{W: boundary.W, H: boundary.H})
+		p.Boundary = editorBoxString(bounds)
+		p.CTM = TranslationMatrix(-bounds.X, -bounds.Y).Multiply(m).String()
+	}
 	p.AbbreviatedData = shape.AbbreviatedData
 	return p, nil
 }

ofdgo_writer.go

@@ -437,7 +437,7 @@ func (x *ofdXML) object(object GraphicObject, root bool) {
 		attrs.flag("Fill", obj.Fill)
 		attrs.alpha(obj.Alpha)
 		fill, stroke = obj.FillColor, (*FillColor)(obj.StrokeColor)
-	case "PathObject":
+	case "PathObject", "Path":
 		obj := object.PathObject
 		attrs.add("ID", obj.ID)
 		attrs.add("Boundary", obj.Boundary)
@@ -467,7 +467,9 @@ func (x *ofdXML) object(object GraphicObject, root bool) {
 		attrs.alpha(obj.Alpha)
 	}
 	x.start(object.Type, attrs)
-	if object.Type == "PathObject" {
+	if object.Type == "ImageObject" {
+		x.clips(object.ImageObject.Clips)
+	} else if object.Type == "PathObject" || object.Type == "Path" {
 		x.color("StrokeColor", stroke)
 		x.color("FillColor", fill)
 		x.text("AbbreviatedData", object.PathObject.AbbreviatedData)
@@ -486,6 +488,31 @@ func (x *ofdXML) object(object GraphicObject, root bool) {
 	x.end(object.Type)
 }
 
+// clips 写出图片路径裁剪，保留裁剪集合、区域及路径的变换
+// 入参: clips 裁剪集合，nil不输出节点
+func (x *ofdXML) clips(clips *Clips) {
+	if clips == nil {
+		return
+	}
+	var attrs ofdAttrs
+	attrs.flag("TransFlag", clips.TransFlag)
+	x.start("Clips", attrs)
+	for _, clip := range clips.Clip {
+		x.start("Clip", nil)
+		for _, area := range clip.Area {
+			var attrs ofdAttrs
+			attrs.add("CTM", area.CTM)
+			x.start("Area", attrs)
+			for _, path := range area.Path {
+				x.object(GraphicObject{Type: "Path", PathObject: path}, false)
+			}
+			x.end("Area")
+		}
+		x.end("Clip")
+	}
+	x.end("Clips")
+}
+
 // textCode 使用XML字符引用转义空格，避免依赖阅读器保留原始空白
 // 入参: value OFD文字内容, attrs 文字定位属性
 func (x *ofdXML) textCode(value string, attrs ofdAttrs) {