From 2d484869a517521f1456076bf0de0b6602ce6cb5 Mon Sep 17 00:00:00 2001
From: Ashish Bhattarai <ashishbhattarai@pm.me>
Date: Wed, 18 Mar 2026 17:49:40 +0100
Subject: [PATCH] Fix svg element clipping

---
 lib/write_svg.js | 36 ++++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/lib/write_svg.js b/lib/write_svg.js
index 077838b..8bd3096 100644
--- a/lib/write_svg.js
+++ b/lib/write_svg.js
@@ -159,6 +159,11 @@ export default function (doc, svg, x, y, options) {
     white: [NamedColors.white, 1],
     transparent: [NamedColors.black, 0],
   };
+  const RGBDefaultColors = {
+    black: [NamedColors.black, 1],
+    white: [NamedColors.white, 1],
+    transparent: [NamedColors.black, 0],
+  };
   const Entities = {
     quot: 34,
     amp: 38,
@@ -694,7 +699,7 @@ export default function (doc, svg, x, y, options) {
     doc.page.xobjects[group.name] = group.xobj;
     doc.addContent('/' + group.name + ' Do');
   }
-  function docApplyMask(group, clip) {
+  function docApplyMask(group) {
     let name = 'M' + (doc._maskCount = (doc._maskCount || 0) + 1);
     let gstate = doc.ref({
       Type: 'ExtGState',
@@ -702,10 +707,8 @@ export default function (doc, svg, x, y, options) {
       ca: 1,
       BM: 'Normal',
       SMask: {
-        // Needs to be Alpha for clipping to work with cmyk color space
-        // Clipping mode is reproducing svg clip-path by drawing everything inside clip path with DefaultColors.white [1,1,1,1]
-        // And everything outside (not draw, defaults to [0,0,0,0]) is masked off
-        S: clip ? 'Alpha' : 'Luminosity',
+        // This should ideally be an Alpha mask for clipping but when we set it to Alpha the firefox pdf viewer doesn't render masks correctly
+        S: 'Luminosity',
         G: group.xobj,
         BC: maskBackdrop,
       },
@@ -850,7 +853,16 @@ export default function (doc, svg, x, y, options) {
   function docEndText() {
     doc.addContent('ET');
   }
-  function docFillColor(color) {
+  function docFillColor(color, isClip) {
+    if (isClip) {
+      // always write clips in RGB colorspace
+      const oldColorProfile = doc._activeColorProfile;
+      doc._activeColorProfile = null;
+      doc.fillColor(RGBDefaultColors.white[0], RGBDefaultColors.white[1]);
+      doc._activeColorProfile = oldColorProfile;
+      return;
+    }
+
     if (color[0].constructor.name === 'PDFPattern') {
       doc.fillOpacity(color[1]);
       docUsePattern(color[0], false);
@@ -2747,7 +2759,7 @@ export default function (doc, svg, x, y, options) {
         doc.image(image, 0, 0);
       } else {
         doc.rect(0, 0, image.width, image.height);
-        docFillColor(DefaultColors.white).fill();
+        docFillColor(DefaultColors.white, true);
       }
       doc.restore();
     };
@@ -3099,7 +3111,7 @@ export default function (doc, svg, x, y, options) {
         }
       } else {
         this.shape.insertInDocument();
-        docFillColor(DefaultColors.white);
+        docFillColor(DefaultColors.white, true);
         doc.fill(this.get('clip-rule'));
       }
       doc.restore();
@@ -3312,7 +3324,7 @@ export default function (doc, svg, x, y, options) {
       this.drawChildren(true, false);
       doc.restore();
       docEndGroup(group);
-      docApplyMask(group, true);
+      docApplyMask(group);
     };
   };
 
@@ -3340,7 +3352,7 @@ export default function (doc, svg, x, y, options) {
       this.drawChildren(false, true);
       doc.restore();
       docEndGroup(group);
-      docApplyMask(group, false);
+      docApplyMask(group);
     };
   };
 
@@ -3412,7 +3424,7 @@ export default function (doc, svg, x, y, options) {
             }
             if (fill || stroke || isClip) {
               if (fill) {
-                docFillColor(fill);
+                docFillColor(fill, isClip);
               }
               if (stroke && strokeWidth) {
                 docStrokeColor(stroke);
@@ -3446,7 +3458,7 @@ export default function (doc, svg, x, y, options) {
       let fill = this.getFill(isClip, isMask),
         stroke = this.getStroke(isClip, isMask);
       if (fill) {
-        docFillColor(fill);
+        docFillColor(fill, isClip);
       }
       if (stroke) {
         docStrokeColor(stroke);