优化预览

src/utils.ts

@@ -152,6 +152,27 @@ export const DEFAULT_CUT_LINE_CONFIG: CutLineConfig = {
   color: '#cccccc',
 };
 
+/** 裁切线有效线宽 (mm)，预览与 PDF 共用 */
+export function getCutLineStrokeWidthMm(cutLine: Pick<CutLineConfig, 'width'>): number {
+  return Math.max(0.02, cutLine.width);
+}
+
+/** 虚线单段长度 (mm)，预览与 PDF 共用 */
+export function getCutLineDashSegmentMm(cutLine: Pick<CutLineConfig, 'style' | 'width'>): number {
+  if (cutLine.style !== 'dashed') return 0;
+  return Math.max(0.5, cutLine.width * 4);
+}
+
+/** 预览 SVG strokeDasharray，scale 为 mm→px 比例 */
+export function formatCutLineSvgDashArray(
+  cutLine: Pick<CutLineConfig, 'style' | 'width'>,
+  scale: number
+): string | undefined {
+  if (cutLine.style !== 'dashed') return undefined;
+  const seg = getCutLineDashSegmentMm(cutLine) * scale;
+  return `${seg} ${seg}`;
+}
+
 export interface GridCutLinePositions {
   xs: number[];
   ys: number[];