1 files changed, 69 insertions, 0 deletions
diff --git a/gfx/src/nsSize.h b/gfx/src/nsSize.h
new file mode 100644
index 0000000000..df1fa5570e
--- /dev/null
+++ b/gfx/src/nsSize.h
@@ -0,0 +1,69 @@
+/* -*- 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 NSSIZE_H
+#define NSSIZE_H
+
+#include "nsCoord.h"
+#include "mozilla/gfx/BaseSize.h"
+#include "mozilla/gfx/Point.h"
+
+// Maximum allowable size
+inline constexpr nscoord NS_MAXSIZE = nscoord_MAX;
+
+typedef mozilla::gfx::IntSize nsIntSize;
+
+struct nsSize : public mozilla::gfx::BaseSize<nscoord, nsSize> {
+  typedef mozilla::gfx::BaseSize<nscoord, nsSize> Super;
+
+  constexpr nsSize() {}
+  constexpr nsSize(nscoord aWidth, nscoord aHeight) : Super(aWidth, aHeight) {}
+
+  inline mozilla::gfx::IntSize ScaleToNearestPixels(
+      float aXScale, float aYScale, nscoord aAppUnitsPerPixel) const;
+  inline mozilla::gfx::IntSize ToNearestPixels(nscoord aAppUnitsPerPixel) const;
+
+  /**
+   * Return this size scaled to a different appunits per pixel (APP) ratio.
+   * @param aFromAPP the APP to scale from
+   * @param aToAPP the APP to scale to
+   */
+  [[nodiscard]] inline nsSize ScaleToOtherAppUnits(int32_t aFromAPP,
+                                                   int32_t aToAPP) const;
+};
+
+inline mozilla::gfx::IntSize nsSize::ScaleToNearestPixels(
+    float aXScale, float aYScale, nscoord aAppUnitsPerPixel) const {
+  return mozilla::gfx::IntSize(
+      NSToIntRoundUp(NSAppUnitsToDoublePixels(width, aAppUnitsPerPixel) *
+                     aXScale),
+      NSToIntRoundUp(NSAppUnitsToDoublePixels(height, aAppUnitsPerPixel) *
+                     aYScale));
+}
+
+inline mozilla::gfx::IntSize nsSize::ToNearestPixels(
+    nscoord aAppUnitsPerPixel) const {
+  return ScaleToNearestPixels(1.0f, 1.0f, aAppUnitsPerPixel);
+}
+
+inline nsSize nsSize::ScaleToOtherAppUnits(int32_t aFromAPP,
+                                           int32_t aToAPP) const {
+  if (aFromAPP != aToAPP) {
+    nsSize size;
+    size.width = NSToCoordRound(NSCoordScale(width, aFromAPP, aToAPP));
+    size.height = NSToCoordRound(NSCoordScale(height, aFromAPP, aToAPP));
+    return size;
+  }
+  return *this;
+}
+
+inline nsSize IntSizeToAppUnits(mozilla::gfx::IntSize aSize,
+                                nscoord aAppUnitsPerPixel) {
+  return nsSize(NSIntPixelsToAppUnits(aSize.width, aAppUnitsPerPixel),
+                NSIntPixelsToAppUnits(aSize.height, aAppUnitsPerPixel));
+}
+
+#endif /* NSSIZE_H */