From 77f058a34c171e3811af534a7fa08dcc411bf5a1 Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Thu, 5 Jul 2012 00:09:44 +0900
Subject: [PATCH] add floor, ceil, trunc, round

---
 sprout/cmath.hpp                          |  1 +
 sprout/cstdlib/str_to_float.hpp           |  1 -
 sprout/darkroom/materials/texture_map.hpp |  4 +-
 sprout/detail/math/float.hpp              |  8 +--
 sprout/math/ceil.hpp                      | 53 ++++++++++++++++++++
 sprout/math/floor.hpp                     | 53 ++++++++++++++++++++
 sprout/math/functions.hpp                 |  1 +
 sprout/math/nearest.hpp                   | 10 ++++
 sprout/math/round.hpp                     | 61 +++++++++++++++++++++++
 sprout/math/trunc.hpp                     | 45 +++++++++++++++++
 sprout/random/binomial_distribution.hpp   |  6 +--
 sprout/random/geometric_distribution.hpp  |  4 +-
 12 files changed, 236 insertions(+), 11 deletions(-)
 create mode 100644 sprout/math/ceil.hpp
 create mode 100644 sprout/math/floor.hpp
 create mode 100644 sprout/math/nearest.hpp
 create mode 100644 sprout/math/round.hpp
 create mode 100644 sprout/math/trunc.hpp

diff --git a/sprout/cmath.hpp b/sprout/cmath.hpp
index 61fbcbc4..9791dc11 100644
--- a/sprout/cmath.hpp
+++ b/sprout/cmath.hpp
@@ -8,5 +8,6 @@
 #include <sprout/math/exponential.hpp>
 #include <sprout/math/power.hpp>
 #include <sprout/math/operations.hpp>
+#include <sprout/math/nearest.hpp>
 
 #endif	// #ifndef SPROUT_CMATH_HPP
diff --git a/sprout/cstdlib/str_to_float.hpp b/sprout/cstdlib/str_to_float.hpp
index 6f3c2ea9..1e640860 100644
--- a/sprout/cstdlib/str_to_float.hpp
+++ b/sprout/cstdlib/str_to_float.hpp
@@ -4,7 +4,6 @@
 #include <cstddef>
 #include <cstdlib>
 #include <limits>
-#include <cmath>
 #include <type_traits>
 #include <sprout/config.hpp>
 #include <sprout/iterator/operation.hpp>
diff --git a/sprout/darkroom/materials/texture_map.hpp b/sprout/darkroom/materials/texture_map.hpp
index 86a76f75..d756b4c7 100644
--- a/sprout/darkroom/materials/texture_map.hpp
+++ b/sprout/darkroom/materials/texture_map.hpp
@@ -3,8 +3,8 @@
 
 #include <cstddef>
 #include <cstdint>
-#include <cmath>
 #include <sprout/config.hpp>
+#include <sprout/math/floor.hpp>
 #include <sprout/utility/value_holder.hpp>
 #include <sprout/darkroom/colors/rgb.hpp>
 
@@ -121,7 +121,7 @@ namespace sprout {
 				}
 				template<typename Unit>
 				SPROUT_CONSTEXPR result_type calc_bilinear(Unit const& x, Unit const& y) const {
-					using std::floor;
+					using sprout::floor;
 					return calc_bilinear_1(x, floor(x - 0.5), floor(x + 0.5), y, floor(y - 0.5), floor(y + 0.5));
 				}
 				template<typename Unit>
diff --git a/sprout/detail/math/float.hpp b/sprout/detail/math/float.hpp
index e3730b5f..0096f58e 100644
--- a/sprout/detail/math/float.hpp
+++ b/sprout/detail/math/float.hpp
@@ -1,9 +1,11 @@
 #ifndef SPROUT_DETAIL_FLOAT_HPP
 #define SPROUT_DETAIL_FLOAT_HPP
 
-#include <cmath>
 #include <type_traits>
 #include <sprout/config.hpp>
+#include <sprout/math/abs.hpp>
+#include <sprout/math/floor.hpp>
+#include <sprout/math/round.hpp>
 #include <sprout/type_traits/enabler_if.hpp>
 
 namespace sprout {
@@ -89,7 +91,7 @@ namespace sprout {
 		template<typename FloatType, typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler>
 		inline SPROUT_CONSTEXPR int
 		float_digit_of_impl(FloatType val) {
-			using std::floor;
+			using sprout::floor;
 			return static_cast<int>((val - floor(val)) * 10);
 		}
 		template<typename FloatType>
@@ -104,7 +106,7 @@ namespace sprout {
 		template<typename FloatType, typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler>
 		inline SPROUT_CONSTEXPR FloatType
 		float_round_impl(FloatType val, FloatType p10) {
-			using std::round;
+			using sprout::round;
 			return round(val * p10) / p10;
 		}
 		template<typename FloatType>
diff --git a/sprout/math/ceil.hpp b/sprout/math/ceil.hpp
new file mode 100644
index 00000000..26b914e7
--- /dev/null
+++ b/sprout/math/ceil.hpp
@@ -0,0 +1,53 @@
+#ifndef SPROUT_MATH_CEIL_HPP
+#define SPROUT_MATH_CEIL_HPP
+
+#include <cstdint>
+#include <limits>
+#include <type_traits>
+#include <stdexcept>
+#include <sprout/config.hpp>
+#include <sprout/math/detail/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<typename FloatType>
+			inline SPROUT_CONSTEXPR FloatType
+			ceil_impl(FloatType x, FloatType x0) {
+				return x - x0 < std::numeric_limits<FloatType>::epsilon()
+					? x0
+					: x0 + 1
+					;
+			}
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			ceil(FloatType x) {
+				return std::numeric_limits<std::uintmax_t>::max() < x || std::numeric_limits<std::uintmax_t>::max() < -x
+					? throw std::domain_error("ceil: Sorry, not implemented.")
+					: x < 0
+						? -static_cast<FloatType>(static_cast<std::uintmax_t>(-x))
+						: sprout::math::detail::ceil_impl(x, static_cast<FloatType>(static_cast<std::uintmax_t>(x)))
+					;
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			ceil(IntType x) {
+				return sprout::math::detail::ceil(static_cast<double>(x));
+			}
+		}	// namespacedetailmath
+
+		using NS_SPROUT_MATH_DETAIL::ceil;
+	}	// namespace math
+
+	using sprout::math::ceil;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_CEIL_HPP
diff --git a/sprout/math/floor.hpp b/sprout/math/floor.hpp
new file mode 100644
index 00000000..1267e2ef
--- /dev/null
+++ b/sprout/math/floor.hpp
@@ -0,0 +1,53 @@
+#ifndef SPROUT_MATH_FLOOR_HPP
+#define SPROUT_MATH_FLOOR_HPP
+
+#include <cstdint>
+#include <limits>
+#include <type_traits>
+#include <stdexcept>
+#include <sprout/config.hpp>
+#include <sprout/math/detail/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<typename FloatType>
+			inline SPROUT_CONSTEXPR FloatType
+			floor_impl(FloatType x, FloatType x0) {
+				return x0 - x < std::numeric_limits<FloatType>::epsilon()
+					? x0
+					: x0 - 1
+					;
+			}
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			floor(FloatType x) {
+				return std::numeric_limits<std::uintmax_t>::max() < x || std::numeric_limits<std::uintmax_t>::max() < -x
+					? throw std::domain_error("floor: Sorry, not implemented.")
+					: x < 0
+						? sprout::math::detail::floor_impl(x, -static_cast<FloatType>(static_cast<std::uintmax_t>(-x)))
+						: static_cast<FloatType>(static_cast<std::uintmax_t>(x))
+					;
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			floor(IntType x) {
+				return sprout::math::detail::floor(static_cast<double>(x));
+			}
+		}	// namespacedetailmath
+
+		using NS_SPROUT_MATH_DETAIL::floor;
+	}	// namespace math
+
+	using sprout::math::floor;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_FLOOR_HPP
diff --git a/sprout/math/functions.hpp b/sprout/math/functions.hpp
index 1b6bb004..37ab90d0 100644
--- a/sprout/math/functions.hpp
+++ b/sprout/math/functions.hpp
@@ -8,6 +8,7 @@
 #include <sprout/math/exponential.hpp>
 #include <sprout/math/power.hpp>
 #include <sprout/math/operations.hpp>
+#include <sprout/math/nearest.hpp>
 #include <sprout/math/common_factor.hpp>
 #include <sprout/math/factorial.hpp>
 #include <sprout/math/bernoulli.hpp>
diff --git a/sprout/math/nearest.hpp b/sprout/math/nearest.hpp
new file mode 100644
index 00000000..9ac91dde
--- /dev/null
+++ b/sprout/math/nearest.hpp
@@ -0,0 +1,10 @@
+#ifndef SPROUT_MATH_NEAREST_HPP
+#define SPROUT_MATH_NEAREST_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/math/ceil.hpp>
+#include <sprout/math/floor.hpp>
+#include <sprout/math/trunc.hpp>
+#include <sprout/math/round.hpp>
+
+#endif	// #ifndef SPROUT_MATH_NEAREST_HPP
diff --git a/sprout/math/round.hpp b/sprout/math/round.hpp
new file mode 100644
index 00000000..f981e5c5
--- /dev/null
+++ b/sprout/math/round.hpp
@@ -0,0 +1,61 @@
+#ifndef SPROUT_MATH_ROUND_HPP
+#define SPROUT_MATH_ROUND_HPP
+
+#include <cstdint>
+#include <limits>
+#include <type_traits>
+#include <stdexcept>
+#include <sprout/config.hpp>
+#include <sprout/math/detail/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<typename FloatType>
+			inline SPROUT_CONSTEXPR FloatType
+			round_impl_positive(FloatType x, FloatType x0) {
+				return x - x0 < FloatType(0.5)
+					? x0
+					: x0 + 1
+					;
+			}
+			template<typename FloatType>
+			inline SPROUT_CONSTEXPR FloatType
+			round_impl_nagative(FloatType x, FloatType x0) {
+				return x0 - x < FloatType(0.5)
+					? x0
+					: x0 - 1
+					;
+			}
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			round(FloatType x) {
+				return std::numeric_limits<std::uintmax_t>::max() < x || std::numeric_limits<std::uintmax_t>::max() < -x
+					? throw std::domain_error("round: Sorry, not implemented.")
+					: x < 0
+						? sprout::math::detail::round_impl_nagative(x, -static_cast<FloatType>(static_cast<std::uintmax_t>(-x)))
+						: sprout::math::detail::round_impl_positive(x, static_cast<FloatType>(static_cast<std::uintmax_t>(x)))
+					;
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			round(IntType x) {
+				return sprout::math::detail::round(static_cast<double>(x));
+			}
+		}	// namespacedetailmath
+
+		using NS_SPROUT_MATH_DETAIL::round;
+	}	// namespace math
+
+	using sprout::math::round;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_ROUND_HPP
diff --git a/sprout/math/trunc.hpp b/sprout/math/trunc.hpp
new file mode 100644
index 00000000..99d3ac98
--- /dev/null
+++ b/sprout/math/trunc.hpp
@@ -0,0 +1,45 @@
+#ifndef SPROUT_MATH_TRUNC_HPP
+#define SPROUT_MATH_TRUNC_HPP
+
+#include <cstdint>
+#include <limits>
+#include <type_traits>
+#include <stdexcept>
+#include <sprout/config.hpp>
+#include <sprout/math/detail/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+
+namespace sprout {
+	namespace math {
+		namespace detail {
+			template<
+				typename FloatType,
+				typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR FloatType
+			trunc(FloatType x) {
+				return std::numeric_limits<std::uintmax_t>::max() < x || std::numeric_limits<std::uintmax_t>::max() < -x
+					? throw std::domain_error("trunc: Sorry, not implemented.")
+					: x < 0
+						? -static_cast<FloatType>(static_cast<std::uintmax_t>(-x))
+						: static_cast<FloatType>(static_cast<std::uintmax_t>(x))
+					;
+			}
+
+			template<
+				typename IntType,
+				typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
+			>
+			inline SPROUT_CONSTEXPR double
+			trunc(IntType x) {
+				return sprout::math::detail::trunc(static_cast<double>(x));
+			}
+		}	// namespacedetailmath
+
+		using NS_SPROUT_MATH_DETAIL::trunc;
+	}	// namespace math
+
+	using sprout::math::trunc;
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_TRUNC_HPP
diff --git a/sprout/random/binomial_distribution.hpp b/sprout/random/binomial_distribution.hpp
index 066e7e6c..6c7a2ae6 100644
--- a/sprout/random/binomial_distribution.hpp
+++ b/sprout/random/binomial_distribution.hpp
@@ -1,7 +1,6 @@
 #ifndef SPROUT_RANDOM_BINOMIAL_DISTRIBUTION_HPP
 #define SPROUT_RANDOM_BINOMIAL_DISTRIBUTION_HPP
 
-#include <cmath>
 #include <iosfwd>
 #include <istream>
 #include <stdexcept>
@@ -12,6 +11,7 @@
 #include <sprout/math/log.hpp>
 #include <sprout/math/pow.hpp>
 #include <sprout/math/sqrt.hpp>
+#include <sprout/math/floor.hpp>
 #include <sprout/random/random_result.hpp>
 #include <sprout/random/uniform_01.hpp>
 
@@ -307,7 +307,7 @@ namespace sprout {
 			}
 			template<typename Engine>
 			SPROUT_CONSTEXPR sprout::random::random_result<Engine, binomial_distribution> generate_4(Engine const& eng, RealType v, RealType u, RealType us) const {
-				using std::floor;
+				using sprout::floor;
 				return generate_5(eng, v, u, us, static_cast<IntType>(floor((2 * btrd_.a / us + btrd_.b) * u + btrd_.c)));
 			}
 			template<typename Engine>
@@ -332,7 +332,7 @@ namespace sprout {
 			}
 			template<typename Engine>
 			SPROUT_CONSTEXPR sprout::random::random_result<Engine, binomial_distribution> generate_1_1(Engine const& eng, RealType u) const {
-				using std::floor;
+				using sprout::floor;
 				using sprout::abs;
 				return sprout::random::random_result<Engine, binomial_distribution>(
 					static_cast<IntType>(floor((2 * btrd_.a / (RealType(0.5) - abs(u)) + btrd_.b) * u + btrd_.c)),
diff --git a/sprout/random/geometric_distribution.hpp b/sprout/random/geometric_distribution.hpp
index d769bed2..abcfd189 100644
--- a/sprout/random/geometric_distribution.hpp
+++ b/sprout/random/geometric_distribution.hpp
@@ -1,12 +1,12 @@
 #ifndef SPROUT_RANDOM_GEOMETRIC_DISTRIBUTION_HPP
 #define SPROUT_RANDOM_GEOMETRIC_DISTRIBUTION_HPP
 
-#include <cmath>
 #include <ios>
 #include <limits>
 #include <stdexcept>
 #include <sprout/config.hpp>
 #include <sprout/math/log.hpp>
+#include <sprout/math/floor.hpp>
 #include <sprout/random/random_result.hpp>
 #include <sprout/random/uniform_01.hpp>
 
@@ -98,7 +98,7 @@ namespace sprout {
 			template<typename Engine, typename Random>
 			SPROUT_CONSTEXPR sprout::random::random_result<Engine, geometric_distribution> generate_1(Random const& rnd) const {
 				using sprout::log;
-				using std::floor;
+				using sprout::floor;
 				return sprout::random::random_result<Engine, geometric_distribution>(
 					static_cast<IntType>(floor(log(RealType(1) - rnd.result()) / log_1mp_)),
 					rnd.engine(),