Add float version of gfx::Range

ui/gfx/range/range.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// 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.h"
 
-#include <algorithm>
-#include <limits>
-
-#include "base/format_macros.h"
-#include "base/logging.h"
-#include "base/strings/stringprintf.h"
+#include "base/float_util.h"
 
 namespace gfx {
 
-Range::Range()
-    : start_(0),
-      end_(0) {
+namespace internal {
+
+template <>
+TRangeBase<size_t> InvalidRange<size_t>() {
+  return TRangeBase<size_t>(std::numeric_limits<size_t>::max(),
+                            std::numeric_limits<size_t>::max());
 }
 
-Range::Range(size_t start, size_t end)
-    : start_(start),
-      end_(end) {
+template <>
+TRangeBase<float> InvalidRange<float>() {
+  return TRangeBase<float>(std::numeric_limits<double>::quiet_NaN(),
+                           std::numeric_limits<double>::quiet_NaN());
 }
 
-Range::Range(size_t position)
-    : start_(position),
-      end_(position) {
+bool IsValidRange(const TRangeBase<size_t>& range) {
+  return range != InvalidRange<size_t>();
 }
 
-// static
-const Range Range::InvalidRange() {
-  return Range(std::numeric_limits<size_t>::max());
+bool IsValidRange(const TRangeBase<float>& range) {
+  return !base::IsNaN(range.start()) && !base::IsNaN(range.end());
 }
 
-bool Range::IsValid() const {
-  return *this != InvalidRange();
+size_t RangeLength(const TRangeBase<size_t>& range) {
+  ptrdiff_t length = range.end() - range.start();
+  return length >= 0 ? length : -length;
 }
 
-size_t Range::GetMin() const {
-  return std::min(start(), end());
+float RangeLength(const TRangeBase<float>& range) {
+  float length = range.end() - range.start();
+  return length >= 0 ? length : -length;
 }
 
-size_t Range::GetMax() const {
-  return std::max(start(), end());
+bool RangeIsEmpty(const TRangeBase<size_t>& range) {
+  return range.start() == range.end();
 }
 
-bool Range::operator==(const Range& other) const {
-  return start() == other.start() && end() == other.end();
+bool RangeIsEmpty(const TRangeBase<float>& range) {
+  return !range.IsValid() || range.start() == range.end();
 }
 
-bool Range::operator!=(const Range& other) const {
-  return !(*this == other);
-}
-
-bool Range::EqualsIgnoringDirection(const Range& other) const {
-  return GetMin() == other.GetMin() && GetMax() == other.GetMax();
-}
-
-bool Range::Intersects(const Range& range) const {
-  return IsValid() && range.IsValid() &&
-      !(range.GetMax() < GetMin() || range.GetMin() >= GetMax());
-}
-
-bool Range::Contains(const Range& range) const {
-  return IsValid() && range.IsValid() &&
-      GetMin() <= range.GetMin() && range.GetMax() <= GetMax();
-}
-
-Range Range::Intersect(const Range& range) const {
-  size_t min = std::max(GetMin(), range.GetMin());
-  size_t max = std::min(GetMax(), range.GetMax());
-
-  if (min >= max)  // No intersection.
-    return InvalidRange();
-
-  return Range(min, max);
-}
-
-std::string Range::ToString() const {
-  return base::StringPrintf("{%" PRIuS ",%" PRIuS "}", start(), end());
-}
+}  // namespace internal
 
 std::ostream& operator<<(std::ostream& os, const Range& range) {
   return os << range.ToString();
 }
 
+std::ostream& operator<<(std::ostream& os, const RangeF& range) {
+  return os << range.ToString();
+}
+
 }  // namespace gfx