From 97b85d8b7d52292f1587582d10c0f13d69ee8186 Mon Sep 17 00:00:00 2001
From: Jonathan Kew <jkew@mozilla.com>
Date: Tue, 16 Apr 2024 20:10:51 +0000
Subject: [PATCH] Bug 1891630 - Avoid calling GetPathForGlyphs with a
 TextDrawTarget. r=gfx-reviewers,lsalzman

Differential Revision: https://phabricator.services.mozilla.com/D207619
---
 gfx/thebes/COLRFonts.cpp | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/gfx/thebes/COLRFonts.cpp b/gfx/thebes/COLRFonts.cpp
index 6369bf191dc9..4a451f22d31c 100644
--- a/gfx/thebes/COLRFonts.cpp
+++ b/gfx/thebes/COLRFonts.cpp
@@ -1298,8 +1298,7 @@ struct PaintGlyph {
       // Core Text's own color font support may step in and ignore the
       // pattern. So to avoid this, fill the glyph as a path instead.
 #if XP_MACOSX
-      RefPtr<Path> path =
-          aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget);
+      RefPtr<Path> path = GetPathForGlyphs(aState, buffer);
       aState.mDrawTarget->Fill(path, *fillPattern, aState.mDrawOptions);
 #else
       aState.mDrawTarget->FillGlyphs(aState.mScaledFont, buffer, *fillPattern,
@@ -1307,8 +1306,7 @@ struct PaintGlyph {
 #endif
       return true;
     }
-    RefPtr<Path> path =
-        aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget);
+    RefPtr<Path> path = GetPathForGlyphs(aState, buffer);
     aState.mDrawTarget->PushClip(path);
     bool ok = DispatchPaint(aState, aOffset + paintOffset, aBounds);
     aState.mDrawTarget->PopClip();
@@ -1319,10 +1317,19 @@ struct PaintGlyph {
     MOZ_ASSERT(format == kFormat);
     Glyph g{uint16_t(glyphID), Point()};
     GlyphBuffer buffer{&g, 1};
-    RefPtr<Path> path =
-        aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget);
+    RefPtr<Path> path = GetPathForGlyphs(aState, buffer);
     return path->GetFastBounds();
   }
+
+ private:
+  RefPtr<Path> GetPathForGlyphs(const PaintState& aState,
+                                const GlyphBuffer& buffer) const {
+    if (aState.mDrawTarget->GetBackendType() == BackendType::WEBRENDER_TEXT) {
+      RefPtr dt = gfxPlatform::ThreadLocalScreenReferenceDrawTarget();
+      return aState.mScaledFont->GetPathForGlyphs(buffer, dt);
+    }
+    return aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget);
+  }
 };
 
 struct PaintColrGlyph {