1 files changed, 83 insertions, 0 deletions
diff --git a/gfx/layers/apz/src/APZUtils.h b/gfx/layers/apz/src/APZUtils.h
new file mode 100644
index 000000000..222788afa
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+++ b/gfx/layers/apz/src/APZUtils.h
@@ -0,0 +1,83 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set sw=2 ts=8 et 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 mozilla_layers_APZUtils_h
+#define mozilla_layers_APZUtils_h
+
+#include <stdint.h>                     // for uint32_t
+#include "LayersTypes.h"
+#include "UnitTransforms.h"
+#include "mozilla/gfx/Point.h"
+#include "mozilla/FloatingPoint.h"
+
+namespace mozilla {
+namespace layers {
+
+enum HitTestResult {
+  HitNothing,
+  HitLayer,
+  HitLayerTouchActionNone,
+  HitLayerTouchActionPanX,
+  HitLayerTouchActionPanY,
+  HitLayerTouchActionPanXY,
+  HitDispatchToContentRegion,
+};
+
+enum CancelAnimationFlags : uint32_t {
+  Default = 0x0,            /* Cancel all animations */
+  ExcludeOverscroll = 0x1,  /* Don't clear overscroll */
+  ScrollSnap = 0x2          /* Snap to snap points */
+};
+
+inline CancelAnimationFlags
+operator|(CancelAnimationFlags a, CancelAnimationFlags b)
+{
+  return static_cast<CancelAnimationFlags>(static_cast<int>(a)
+                                         | static_cast<int>(b));
+}
+
+enum class ScrollSource {
+  // scrollTo() or something similar.
+  DOM,
+
+  // Touch-screen or trackpad with gesture support.
+  Touch,
+
+  // Mouse wheel.
+  Wheel
+};
+
+typedef uint32_t TouchBehaviorFlags;
+
+// Epsilon to be used when comparing 'float' coordinate values
+// with FuzzyEqualsAdditive. The rationale is that 'float' has 7 decimal
+// digits of precision, and coordinate values should be no larger than in the
+// ten thousands. Note also that the smallest legitimate difference in page
+// coordinates is 1 app unit, which is 1/60 of a (CSS pixel), so this epsilon
+// isn't too large.
+const float COORDINATE_EPSILON = 0.01f;
+
+template <typename Units>
+static bool IsZero(const gfx::PointTyped<Units>& aPoint)
+{
+  return FuzzyEqualsAdditive(aPoint.x, 0.0f, COORDINATE_EPSILON)
+      && FuzzyEqualsAdditive(aPoint.y, 0.0f, COORDINATE_EPSILON);
+}
+
+// Deem an AsyncTransformComponentMatrix (obtained by multiplying together
+// one or more AsyncTransformComponentMatrix objects) as constituting a
+// complete async transform.
+inline AsyncTransformMatrix
+CompleteAsyncTransform(const AsyncTransformComponentMatrix& aMatrix)
+{
+  return ViewAs<AsyncTransformMatrix>(aMatrix,
+      PixelCastJustification::MultipleAsyncTransforms);
+}
+
+} // namespace layers
+} // namespace mozilla
+
+#endif // mozilla_layers_APZUtils_h