1 files changed, 54 insertions, 0 deletions
diff --git a/gfx/layers/basic/AutoMaskData.h b/gfx/layers/basic/AutoMaskData.h
new file mode 100644
index 0000000000..8775c8c33d
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+++ b/gfx/layers/basic/AutoMaskData.h
@@ -0,0 +1,54 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef GFX_AUTOMASKDATA_H_
+#define GFX_AUTOMASKDATA_H_
+
+#include "mozilla/layers/LayersSurfaces.h"  // for SurfaceDescriptor
+
+namespace mozilla {
+namespace layers {
+
+/**
+ * Drawing with a mask requires a mask surface and a transform.
+ *
+ * This helper class manages the SourceSurface logic.
+ */
+class MOZ_STACK_CLASS AutoMoz2DMaskData {
+ public:
+  AutoMoz2DMaskData() = default;
+  ~AutoMoz2DMaskData() = default;
+
+  void Construct(const gfx::Matrix& aTransform, gfx::SourceSurface* aSurface) {
+    MOZ_ASSERT(!IsConstructed());
+    mTransform = aTransform;
+    mSurface = aSurface;
+  }
+
+  gfx::SourceSurface* GetSurface() {
+    MOZ_ASSERT(IsConstructed());
+    return mSurface.get();
+  }
+
+  const gfx::Matrix& GetTransform() {
+    MOZ_ASSERT(IsConstructed());
+    return mTransform;
+  }
+
+ private:
+  bool IsConstructed() { return !!mSurface; }
+
+  gfx::Matrix mTransform;
+  RefPtr<gfx::SourceSurface> mSurface;
+
+  AutoMoz2DMaskData(const AutoMoz2DMaskData&) = delete;
+  AutoMoz2DMaskData& operator=(const AutoMoz2DMaskData&) = delete;
+};
+
+}  // namespace layers
+}  // namespace mozilla
+
+#endif  // GFX_AUTOMASKDATA_H_