1 files changed, 90 insertions, 0 deletions
diff --git a/chromium/third_party/blink/renderer/core/layout/geometry/writing_mode_converter.cc b/chromium/third_party/blink/renderer/core/layout/geometry/writing_mode_converter.cc
new file mode 100644
index 00000000000..4de9df959bf
--- /dev/null
+++ b/chromium/third_party/blink/renderer/core/layout/geometry/writing_mode_converter.cc
@@ -0,0 +1,90 @@
+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "third_party/blink/renderer/core/layout/geometry/writing_mode_converter.h"
+
+namespace blink {
+
+LogicalOffset WritingModeConverter::SlowToLogical(
+    const PhysicalOffset& offset,
+    const PhysicalSize& inner_size) const {
+  switch (GetWritingMode()) {
+    case WritingMode::kHorizontalTb:
+      DCHECK(!IsLtr());  // LTR is in the fast code path.
+      return LogicalOffset(outer_size_.width - offset.left - inner_size.width,
+                           offset.top);
+    case WritingMode::kVerticalRl:
+    case WritingMode::kSidewaysRl:
+      if (IsLtr()) {
+        return LogicalOffset(
+            offset.top, outer_size_.width - offset.left - inner_size.width);
+      }
+      return LogicalOffset(outer_size_.height - offset.top - inner_size.height,
+                           outer_size_.width - offset.left - inner_size.width);
+    case WritingMode::kVerticalLr:
+      if (IsLtr())
+        return LogicalOffset(offset.top, offset.left);
+      return LogicalOffset(outer_size_.height - offset.top - inner_size.height,
+                           offset.left);
+    case WritingMode::kSidewaysLr:
+      if (IsLtr()) {
+        return LogicalOffset(
+            outer_size_.height - offset.top - inner_size.height, offset.left);
+      }
+      return LogicalOffset(offset.top, offset.left);
+  }
+  NOTREACHED();
+  return LogicalOffset();
+}
+
+PhysicalOffset WritingModeConverter::SlowToPhysical(
+    const LogicalOffset& offset,
+    const PhysicalSize& inner_size) const {
+  switch (GetWritingMode()) {
+    case WritingMode::kHorizontalTb:
+      DCHECK(!IsLtr());  // LTR is in the fast code path.
+      return PhysicalOffset(
+          outer_size_.width - offset.inline_offset - inner_size.width,
+          offset.block_offset);
+    case WritingMode::kVerticalRl:
+    case WritingMode::kSidewaysRl:
+      if (IsLtr()) {
+        return PhysicalOffset(
+            outer_size_.width - offset.block_offset - inner_size.width,
+            offset.inline_offset);
+      }
+      return PhysicalOffset(
+          outer_size_.width - offset.block_offset - inner_size.width,
+          outer_size_.height - offset.inline_offset - inner_size.height);
+    case WritingMode::kVerticalLr:
+      if (IsLtr())
+        return PhysicalOffset(offset.block_offset, offset.inline_offset);
+      return PhysicalOffset(
+          offset.block_offset,
+          outer_size_.height - offset.inline_offset - inner_size.height);
+    case WritingMode::kSidewaysLr:
+      if (IsLtr()) {
+        return PhysicalOffset(
+            offset.block_offset,
+            outer_size_.height - offset.inline_offset - inner_size.height);
+      }
+      return PhysicalOffset(offset.block_offset, offset.inline_offset);
+  }
+  NOTREACHED();
+  return PhysicalOffset();
+}
+
+LogicalRect WritingModeConverter::SlowToLogical(
+    const PhysicalRect& rect) const {
+  return LogicalRect(SlowToLogical(rect.offset, rect.size),
+                     ToLogical(rect.size));
+}
+
+PhysicalRect WritingModeConverter::SlowToPhysical(
+    const LogicalRect& rect) const {
+  const PhysicalSize size = ToPhysical(rect.size);
+  return PhysicalRect(SlowToPhysical(rect.offset, size), size);
+}
+
+}  // namespace blink