Add float version of gfx::Range

ui/gfx/range/range_f.cc

+// Copyright 2015 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 "ui/gfx/range/range_f.h"
+
+#include <algorithm>
+#include <limits>
+
+#include "base/float_util.h"
+#include "base/format_macros.h"
+#include "base/strings/stringprintf.h"
+
+namespace gfx {
+
+RangeF::RangeF()
+    : start_(0.0f),
+      end_(0.0f) {
+}
+
+RangeF::RangeF(float start, float end)
+    : start_(start),
+      end_(end) {
+}
+
+RangeF::RangeF(float position)
+    : start_(position),
+      end_(position) {
+}
+
+// static
+const RangeF RangeF::InvalidRange() {
+  return RangeF(std::numeric_limits<double>::quiet_NaN());
+}
+
+bool RangeF::IsValid() const {
+  return !base::IsNaN(start_) && !base::IsNaN(end_);

[Robert Sesek, 2015/02/12 16:52:37]

Use start() and end() like the rest of the implementation does.

[msw, 2015/02/12 21:01:04]

Can this just "return *this != InvalidRange();" like Range?

[ckocagil, 2015/02/13 18:47:47]

No. NaN isn't equal to any other value, including NaN.

[ckocagil, 2015/02/13 18:47:47]

Done.

+}
+
+float RangeF::GetMin() const {
+  return std::min(start(), end());
+}
+
+float RangeF::GetMax() const {
+  return std::max(start(), end());
+}
+
+bool RangeF::operator==(const RangeF& other) const {
+  return start() == other.start() && end() == other.end();
+}
+
+bool RangeF::operator!=(const RangeF& other) const {
+  return !(*this == other);
+}
+
+bool RangeF::EqualsIgnoringDirection(const RangeF& other) const {
+  return GetMin() == other.GetMin() && GetMax() == other.GetMax();
+}
+
+bool RangeF::Intersects(const RangeF& range) const {
+  return IsValid() && range.IsValid() &&
+      !(range.GetMax() < GetMin() || range.GetMin() >= GetMax());
+}
+
+bool RangeF::Contains(const RangeF& range) const {
+  return IsValid() && range.IsValid() &&
+      GetMin() <= range.GetMin() && range.GetMax() <= GetMax();
+}
+
+RangeF RangeF::Intersect(const RangeF& range) const {
+  float min = std::max(GetMin(), range.GetMin());
+  float max = std::min(GetMax(), range.GetMax());
+
+  if (min >= max)  // No intersection.
+    return InvalidRange();
+
+  return RangeF(min, max);
+}
+
+std::string RangeF::ToString() const {
+  return base::StringPrintf("{%f,%f}", start(), end());
+}
+
+std::ostream& operator<<(std::ostream& os, const RangeF& range) {
+  return os << range.ToString();
+}
+
+}  // namespace gfx