From b7cf29d767b30d84c9d57d20735aa95e6429271e Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Sun, 25 Nov 2012 23:52:25 +0900
Subject: [PATCH] add compost auto_pan, vocal_cancelled

---
 sprout/compost/effects.hpp                 |   2 +
 sprout/compost/effects/auto_pan.hpp        | 158 +++++++++++++++++++++
 sprout/compost/effects/vocal_cancelled.hpp |  53 +++++++
 3 files changed, 213 insertions(+)
 create mode 100644 sprout/compost/effects/auto_pan.hpp
 create mode 100644 sprout/compost/effects/vocal_cancelled.hpp

diff --git a/sprout/compost/effects.hpp b/sprout/compost/effects.hpp
index 5e6a5329..91e3f126 100644
--- a/sprout/compost/effects.hpp
+++ b/sprout/compost/effects.hpp
@@ -13,8 +13,10 @@
 #include <sprout/compost/effects/tremolo.hpp>
 #include <sprout/compost/effects/vibrato.hpp>
 #include <sprout/compost/effects/chorus.hpp>
+#include <sprout/compost/effects/auto_pan.hpp>
 #include <sprout/compost/effects/pseudo_stereo.hpp>
 #include <sprout/compost/effects/noise_gated.hpp>
+#include <sprout/compost/effects/vocal_cancelled.hpp>
 #include <sprout/compost/effects/superposed.hpp>
 
 #endif	// #ifndef SPROUT_COMPOST_EFFECTS_HPP
diff --git a/sprout/compost/effects/auto_pan.hpp b/sprout/compost/effects/auto_pan.hpp
new file mode 100644
index 00000000..7dec17a6
--- /dev/null
+++ b/sprout/compost/effects/auto_pan.hpp
@@ -0,0 +1,158 @@
+#ifndef SPROUT_COMPOST_EFFECTS_AUTO_PAN_HPP
+#define SPROUT_COMPOST_EFFECTS_AUTO_PAN_HPP
+
+#include <iterator>
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/utility/lvalue_forward.hpp>
+#include <sprout/math/constants.hpp>
+#include <sprout/math/sin.hpp>
+#include <sprout/range/adaptor/transformed.hpp>
+#include <sprout/range/adaptor/outdirected.hpp>
+#include <sprout/range/adaptor/indexed.hpp>
+#include <sprout/compost/formats/stereo.hpp>
+
+namespace sprout {
+	namespace compost {
+		//
+		// auto_pan_outdirected_value
+		//
+		template<typename Value, typename IntType, bool IsLeft>
+		struct auto_pan_outdirected_value {
+		public:
+			typedef Value value_type;
+			typedef IntType int_type;
+		private:
+			value_type depth_;
+			value_type rate_;
+			int_type samples_per_sec_;
+		private:
+			template<bool Left, typename Outdirected>
+			SPROUT_CONSTEXPR typename std::enable_if<
+				Left,
+				typename std::iterator_traits<Outdirected>::value_type
+			>::type
+			calc(Outdirected const& x) const {
+				return (1 + depth_ * sprout::sin(2 * sprout::math::pi<Value>() * rate_ * x.index() / samples_per_sec_)) * *x;
+			}
+			template<bool Left, typename Outdirected>
+			SPROUT_CONSTEXPR typename std::enable_if<
+				!Left,
+				typename std::iterator_traits<Outdirected>::value_type
+			>::type
+			calc(Outdirected const& x) const {
+				return (1 + depth_ * sprout::sin(2 * sprout::math::pi<Value>() * rate_ * x.index() / samples_per_sec_ + sprout::math::pi<Value>())) * *x;
+			}
+		public:
+			SPROUT_CONSTEXPR auto_pan_outdirected_value(
+				value_type const& depth, value_type const& rate,
+				int_type samples_per_sec = 44100
+				)
+				: depth_(depth), rate_(rate), samples_per_sec_(samples_per_sec)
+			{}
+			template<typename Outdirected>
+			SPROUT_CONSTEXPR typename std::iterator_traits<Outdirected>::value_type
+			operator()(Outdirected const& x) const {
+				return calc<IsLeft>(x);
+			}
+		};
+
+		namespace effects {
+			//
+			// auto_pan_holder
+			//
+			template<typename T, typename IntType = int>
+			class auto_pan_holder {
+			public:
+				typedef T value_type;
+				typedef IntType int_type;
+			private:
+				value_type depth_;
+				value_type rate_;
+				int_type samples_per_sec_;
+			public:
+				auto_pan_holder() = default;
+				auto_pan_holder(auto_pan_holder const&) = default;
+				SPROUT_CONSTEXPR auto_pan_holder(
+					value_type const& depth, value_type const& rate,
+					int_type samples_per_sec = 44100
+					)
+					: depth_(depth), rate_(rate), samples_per_sec_(samples_per_sec)
+				{}
+				SPROUT_CONSTEXPR value_type const& depth() const {
+					return depth_;
+				}
+				SPROUT_CONSTEXPR value_type const& rate() const {
+					return rate_;
+				}
+				SPROUT_CONSTEXPR int_type const& samples_per_sec() const {
+					return samples_per_sec_;
+				}
+			};
+
+			//
+			// auto_pan_forwarder
+			//
+			class auto_pan_forwarder {
+			public:
+				template<typename T, typename IntType>
+				SPROUT_CONSTEXPR sprout::compost::effects::auto_pan_holder<T, IntType>
+				operator()(T const& depth, T const& rate, IntType samples_per_sec) {
+					return sprout::compost::effects::auto_pan_holder<T, IntType>(depth, rate, samples_per_sec);
+				}
+				template<typename T>
+				SPROUT_CONSTEXPR sprout::compost::effects::auto_pan_holder<T>
+				operator()(T const& depth, T const& rate) {
+					return sprout::compost::effects::auto_pan_holder<T>(depth, rate);
+				}
+			};
+
+			//
+			// auto_pan
+			//
+			namespace {
+				SPROUT_STATIC_CONSTEXPR sprout::compost::effects::auto_pan_forwarder auto_pan{};
+			}	// anonymous-namespace
+
+			//
+			// operator|
+			//
+			template<typename Range, typename T, typename IntType>
+			inline SPROUT_CONSTEXPR auto
+			operator|(Range&& lhs, sprout::compost::effects::auto_pan_holder<T, IntType> const& rhs)
+			-> decltype(
+				sprout::forward<Range>(lhs)
+					| sprout::adaptors::indexed | sprout::adaptors::outdirected
+					| sprout::adaptors::transformed(
+						sprout::compost::auto_pan_outdirected_value<T, IntType, true>(rhs.depth(), rhs.rate(), rhs.samples_per_sec())
+						)
+					| sprout::compost::formats::stereo(
+						sprout::forward<Range>(lhs)
+							| sprout::adaptors::indexed | sprout::adaptors::outdirected
+							| sprout::adaptors::transformed(
+								sprout::compost::auto_pan_outdirected_value<T, IntType, false>(rhs.depth(), rhs.rate(), rhs.samples_per_sec())
+								)
+						)
+				)
+			{
+				return sprout::forward<Range>(lhs)
+					| sprout::adaptors::indexed | sprout::adaptors::outdirected
+					| sprout::adaptors::transformed(
+						sprout::compost::auto_pan_outdirected_value<T, IntType, true>(rhs.depth(), rhs.rate(), rhs.samples_per_sec())
+						)
+					| sprout::compost::formats::stereo(
+						sprout::forward<Range>(lhs)
+							| sprout::adaptors::indexed | sprout::adaptors::outdirected
+							| sprout::adaptors::transformed(
+								sprout::compost::auto_pan_outdirected_value<T, IntType, false>(rhs.depth(), rhs.rate(), rhs.samples_per_sec())
+								)
+						)
+					;
+			}
+		}	// namespace effects
+
+		using sprout::compost::effects::auto_pan;
+	}	// namespace compost
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_COMPOST_EFFECTS_AUTO_PAN_HPP
diff --git a/sprout/compost/effects/vocal_cancelled.hpp b/sprout/compost/effects/vocal_cancelled.hpp
new file mode 100644
index 00000000..6e778ba0
--- /dev/null
+++ b/sprout/compost/effects/vocal_cancelled.hpp
@@ -0,0 +1,53 @@
+#ifndef SPROUT_COMPOST_EFFECTS_VOCAL_CANCELLED_HPP
+#define SPROUT_COMPOST_EFFECTS_VOCAL_CANCELLED_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/utility/lvalue_forward.hpp>
+#include <sprout/functional/minus.hpp>
+#include <sprout/range/adaptor/transformed.hpp>
+#include <sprout/compost/formats/left_channel.hpp>
+#include <sprout/compost/formats/right_channel.hpp>
+
+namespace sprout {
+	namespace compost {
+		namespace effects {
+			//
+			// vocal_cancelled_forwarder
+			//
+			class vocal_cancelled_forwarder {};
+
+			//
+			// vocal_cancelled
+			//
+			namespace {
+				SPROUT_STATIC_CONSTEXPR sprout::compost::effects::vocal_cancelled_forwarder vocal_cancelled{};
+			}	// anonymous-namespace
+
+			//
+			// operator|
+			//
+			template<typename Range>
+			inline SPROUT_CONSTEXPR auto
+			operator|(Range&& lhs, sprout::compost::effects::vocal_cancelled_forwarder const& rhs)
+			-> decltype(
+				sprout::lvalue_forward<Range>(lhs) | sprout::compost::formats::left_channel
+					| sprout::adaptors::transformed(
+						sprout::lvalue_forward<Range>(lhs) | sprout::compost::formats::right_channel,
+						sprout::minus<>()
+						)
+				)
+			{
+				return sprout::lvalue_forward<Range>(lhs) | sprout::compost::formats::left_channel
+					| sprout::adaptors::transformed(
+						sprout::lvalue_forward<Range>(lhs) | sprout::compost::formats::right_channel,
+						sprout::minus<>()
+						)
+					;
+			}
+		}	// namespace effects
+
+		using sprout::compost::effects::vocal_cancelled;
+	}	// namespace compost
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_COMPOST_EFFECTS_VOCAL_CANCELLED_HPP