From 2d089b19d19732756e6dc1b0ea7367ff875af747 Mon Sep 17 00:00:00 2001
From: Zhong <cszhjh@gmail.com>
Date: Wed, 6 Aug 2025 17:55:33 +0800
Subject: [PATCH] fix(components): [watermark] resolve text clipping caused by
 textAlign (#21639)

* fix(components): [watermark] resolve text clipping caused by textAlign

* refactor(components): [watermark] update based on review feeddback

* fix: update
---
 packages/components/watermark/src/useClips.ts   | 15 +++++++++++++--
 packages/components/watermark/src/watermark.vue | 10 ++++++----
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/packages/components/watermark/src/useClips.ts b/packages/components/watermark/src/useClips.ts
index beb3af7df1..f59231889c 100644
--- a/packages/components/watermark/src/useClips.ts
+++ b/packages/components/watermark/src/useClips.ts
@@ -4,6 +4,15 @@ import type { WatermarkProps } from './watermark'
 
 export const FontGap = 3
 
+// [alignRatio, spaceRatio]
+const TEXT_ALIGN_RATIO_MAP = {
+  left: [0, 0.5],
+  start: [0, 0.5],
+  center: [0.5, 0],
+  right: [1, -0.5],
+  end: [1, -0.5],
+} as const
+
 function prepareCanvas(
   width: number,
   height: number,
@@ -39,7 +48,8 @@ export default function useClips() {
     height: number,
     font: Required<NonNullable<WatermarkProps['font']>>,
     gapX: number,
-    gapY: number
+    gapY: number,
+    space: number
   ): [dataURL: string, finalWidth: number, finalHeight: number] {
     // ================= Text / Image =================
     const [ctx, canvas, contentWidth, contentHeight] = prepareCanvas(
@@ -70,9 +80,10 @@ export default function useClips() {
       ctx.textBaseline = textBaseline
       const contents = isArray(content) ? content : [content]
       contents?.forEach((item, index) => {
+        const [alignRatio, spaceRatio] = TEXT_ALIGN_RATIO_MAP[textAlign]
         ctx.fillText(
           item ?? '',
-          contentWidth / 2,
+          contentWidth * alignRatio + space * spaceRatio,
           index * (mergedFontSize + FontGap * ratio)
         )
       })
diff --git a/packages/components/watermark/src/watermark.vue b/packages/components/watermark/src/watermark.vue
index f86145dc72..90d7d2fc9b 100644
--- a/packages/components/watermark/src/watermark.vue
+++ b/packages/components/watermark/src/watermark.vue
@@ -112,6 +112,7 @@ const appendWatermark = (base64Url: string, markWidth: number) => {
 const getMarkSize = (ctx: CanvasRenderingContext2D) => {
   let defaultWidth = 120
   let defaultHeight = 64
+  let space = 0
 
   const { image, content, width, height, rotate } = props
 
@@ -144,12 +145,12 @@ const getMarkSize = (ctx: CanvasRenderingContext2D) => {
       maxHeight * contents.length + (contents.length - 1) * FontGap
 
     const angle = (Math.PI / 180) * Number(rotate)
-    const space = Math.ceil(Math.abs(Math.sin(angle) * defaultHeight) / 2)
+    space = Math.ceil(Math.abs(Math.sin(angle) * defaultHeight) / 2)
 
     defaultWidth += space
   }
 
-  return [width ?? defaultWidth, height ?? defaultHeight] as const
+  return [width ?? defaultWidth, height ?? defaultHeight, space] as const
 }
 
 const getClips = useClips()
@@ -167,7 +168,7 @@ const renderWatermark = () => {
     }
 
     const ratio = getPixelRatio()
-    const [markWidth, markHeight] = getMarkSize(ctx)
+    const [markWidth, markHeight, space] = getMarkSize(ctx)
 
     const drawCanvas = (
       drawContent?: NonNullable<WatermarkProps['content']> | HTMLImageElement
@@ -188,7 +189,8 @@ const renderWatermark = () => {
           textBaseline: textBaseline.value,
         },
         gapX.value,
-        gapY.value
+        gapY.value,
+        space
       )
 
       appendWatermark(textClips, clipWidth)