1 files changed, 41 insertions, 0 deletions
diff --git a/layout/generic/ScrollSnapTargetId.h b/layout/generic/ScrollSnapTargetId.h
new file mode 100644
index 0000000000..e25dd0e341
--- /dev/null
+++ b/layout/generic/ScrollSnapTargetId.h
@@ -0,0 +1,41 @@
+/* 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 mozilla_ScrollSnapTargetId_h_
+#define mozilla_ScrollSnapTargetId_h_
+
+#include <cstdint>
+#include "nsPoint.h"
+#include "nsTArray.h"
+#include "Units.h"
+
+namespace mozilla {
+
+// The id for each scroll snap target element to track the last snapped element.
+// 0 means it wasn't snapped on the last scroll operation.
+enum class ScrollSnapTargetId : uintptr_t {
+  None = 0,
+};
+
+struct ScrollSnapTargetIds {
+  CopyableTArray<ScrollSnapTargetId> mIdsOnX;
+  CopyableTArray<ScrollSnapTargetId> mIdsOnY;
+  bool operator==(const ScrollSnapTargetIds& aOther) const {
+    return mIdsOnX == aOther.mIdsOnX && mIdsOnY == aOther.mIdsOnY;
+  }
+};
+
+struct SnapTarget {
+  nsPoint mPosition;
+  ScrollSnapTargetIds mTargetIds;
+};
+
+struct CSSSnapTarget {
+  CSSPoint mPosition;
+  ScrollSnapTargetIds mTargetIds;
+};
+
+}  // namespace mozilla
+
+#endif  // mozilla_ScrollSnapTargetId_h_