优化

src/tableUtils.ts

@@ -56,18 +56,49 @@ export function getTableColWidths(elem: TemplateElement): number[] {
   return Array.from({ length: cols }, () => even);
 }
 
-/** 内边距变化后保持行高/列宽不变，自动增大元素尺寸 */
+/** 将轨道尺寸总和调整为 targetTotal（保持相对比例，末项吸收取整误差） */
+function scaleTracksToTotal(tracks: number[], targetTotal: number, min = 0.5): number[] {
+  if (tracks.length === 0) return [];
+  const safeTotal = Math.max(tracks.length * min, targetTotal);
+  const current = tracks.reduce((a, b) => a + b, 0);
+  if (current <= 0) {
+    return distributeTracks(safeTotal, tracks.length, min);
+  }
+  const scaled = tracks.map((t) => round1(Math.max(min, (t / current) * safeTotal)));
+  const sum = scaled.reduce((a, b) => a + b, 0);
+  const diff = round1(safeTotal - sum);
+  if (scaled.length > 0 && diff !== 0) {
+    scaled[scaled.length - 1] = round1(Math.max(min, scaled[scaled.length - 1] + diff));
+  }
+  return scaled;
+}
+
+/** 将 inner 区域均分给 count 条轨道（末项吸收取整误差） */
+function distributeTracks(total: number, count: number, min = 0.5): number[] {
+  if (count <= 0) return [];
+  const safeTotal = Math.max(count * min, total);
+  const even = round1(safeTotal / count);
+  const tracks = Array.from({ length: count }, () => even);
+  const sum = tracks.reduce((a, b) => a + b, 0);
+  const diff = round1(safeTotal - sum);
+  if (tracks.length > 0 && diff !== 0) {
+    tracks[tracks.length - 1] = round1(Math.max(min, tracks[tracks.length - 1] + diff));
+  }
+  return tracks;
+}
+
+/** 内边距变化后保持元素外框尺寸不变，按比例重算行高/列宽以适配新的内容区 */
 export function expandTableForPadding(elem: TemplateElement): TemplateElement {
   if (elem.type !== 'table') return elem;
   const pad = resolvePaddingMm(elem);
-  const rowHeights = getTableRowHeights(elem);
-  const colWidths = getTableColWidths(elem);
+  const innerW = Math.max(1, elem.width - pad.left - pad.right);
+  const innerH = Math.max(1, elem.height - pad.top - pad.bottom);
   return {
     ...elem,
-    tableRowHeights: rowHeights,
-    tableColWidths: colWidths,
-    height: round1(rowHeights.reduce((a, b) => a + b, 0) + pad.top + pad.bottom),
-    width: round1(colWidths.reduce((a, b) => a + b, 0) + pad.left + pad.right),
+    tableRowHeights: scaleTracksToTotal(getTableRowHeights(elem), innerH),
+    tableColWidths: scaleTracksToTotal(getTableColWidths(elem), innerW),
+    width: elem.width,
+    height: elem.height,
   };
 }
 
@@ -183,6 +214,53 @@ export function getCellRectMm(
   return { x: round1(x), y: round1(y), width: round1(width), height: round1(height) };
 }
 
+/** 表格行列像素边界（累积取整，避免单元格背景/选区出现缝隙） */
+export function buildTableGridBoundariesPx(
+  elem: TemplateElement,
+  scale: number,
+  originX = 0,
+  originY = 0
+): { rowBounds: number[]; colBounds: number[] } {
+  const pad = resolvePaddingMm(elem);
+  const rowHeights = getTableRowHeights(elem);
+  const colWidths = getTableColWidths(elem);
+
+  const rowBounds: number[] = [originY + Math.round(pad.top * scale)];
+  for (const h of rowHeights) {
+    rowBounds.push(rowBounds[rowBounds.length - 1] + Math.round(h * scale));
+  }
+
+  const colBounds: number[] = [originX + Math.round(pad.left * scale)];
+  for (const w of colWidths) {
+    colBounds.push(colBounds[colBounds.length - 1] + Math.round(w * scale));
+  }
+
+  return { rowBounds, colBounds };
+}
+
+/** 单元格像素矩形，与 canvas 绘制及设计器选区 overlay 对齐 */
+export function getCellRectPx(
+  elem: TemplateElement,
+  row: number,
+  col: number,
+  scale: number,
+  originX = 0,
+  originY = 0
+): { x: number; y: number; width: number; height: number } {
+  const { rowBounds, colBounds } = buildTableGridBoundariesPx(elem, scale, originX, originY);
+  const anchor = getCellAnchor(elem, row, col);
+  const { rowSpan, colSpan } = getCellSpan(elem, anchor.row, anchor.col);
+
+  const x = colBounds[anchor.col];
+  const y = rowBounds[anchor.row];
+  return {
+    x,
+    y,
+    width: colBounds[anchor.col + colSpan] - x,
+    height: rowBounds[anchor.row + rowSpan] - y,
+  };
+}
+
 export function createDefaultTableElement(id: string, index: number): TemplateElement {
   const rows = 3;
   const cols = 3;
@@ -224,28 +302,6 @@ export function resizeTableGrid(
 ): TemplateElement {
   const rows = Math.max(1, Math.min(50, newRows));
   const cols = Math.max(1, Math.min(50, newCols));
-  const oldRows = getTableRows(elem);
-  const oldCols = getTableCols(elem);
-  const { width, height } = getTableInnerSizeMm(elem);
-
-  let rowHeights = getTableRowHeights(elem);
-  let colWidths = getTableColWidths(elem);
-
-  if (rows > oldRows) {
-    const added = rows - oldRows;
-    const avg = rowHeights.reduce((a, b) => a + b, 0) / oldRows;
-    rowHeights = [...rowHeights, ...Array.from({ length: added }, () => round1(avg))];
-  } else if (rows < oldRows) {
-    rowHeights = rowHeights.slice(0, rows);
-  }
-
-  if (cols > oldCols) {
-    const added = cols - oldCols;
-    const avg = colWidths.reduce((a, b) => a + b, 0) / oldCols;
-    colWidths = [...colWidths, ...Array.from({ length: added }, () => round1(avg))];
-  } else if (cols < oldCols) {
-    colWidths = colWidths.slice(0, cols);
-  }
 
   const newCells: Record<string, TableCellData> = {};
   if (elem.tableCells) {
@@ -259,15 +315,18 @@ export function resizeTableGrid(
   }
 
   const pad = resolvePaddingMm(elem);
+  const innerW = Math.max(1, elem.width - pad.left - pad.right);
+  const innerH = Math.max(1, elem.height - pad.top - pad.bottom);
+
   const next: TemplateElement = {
     ...elem,
     tableRows: rows,
     tableCols: cols,
-    tableRowHeights: rowHeights,
-    tableColWidths: colWidths,
+    tableRowHeights: distributeTracks(innerH, rows),
+    tableColWidths: distributeTracks(innerW, cols),
     tableCells: newCells,
-    width: round1(colWidths.reduce((a, b) => a + b, 0) + pad.left + pad.right),
-    height: round1(rowHeights.reduce((a, b) => a + b, 0) + pad.top + pad.bottom),
+    width: elem.width,
+    height: elem.height,
   };
   return sanitizeTableMerges(next);
 }