From d61158fa9e68d330751df0666c796df94fc525ad Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emmanuel=20Beno=C3=AEt?= <tseeker@nocternity.net>
Date: Sat, 7 Oct 2017 16:56:20 +0200
Subject: [PATCH] Definitions for sync data

---
 Makefile     |   1 +
 externals.hh |   1 +
 sync.cc      | 105 +++++++++++++++++++++++++++++++++++++++++++++++++++
 sync.hh      |  63 +++++++++++++++++++++++++++++++
 4 files changed, 170 insertions(+)
 create mode 100644 sync.cc
 create mode 100644 sync.hh

diff --git a/Makefile b/Makefile
index 3a01709..75f2d9d 100644
--- a/Makefile
+++ b/Makefile
@@ -24,6 +24,7 @@ DEMO = \
 	 profiling.cc \
 	 shaders.cc \
 	 odbg.cc \
+	 sync.cc \
 	 \
 	 demo.cc \
 	 \
diff --git a/externals.hh b/externals.hh
index aab13f9..9358efe 100644
--- a/externals.hh
+++ b/externals.hh
@@ -22,6 +22,7 @@
 #include <map>
 #include <set>
 #include <regex>
+#include <unordered_map>
 
 // ImGui
 #include <imgui.h>
diff --git a/sync.cc b/sync.cc
new file mode 100644
index 0000000..779dbf2
--- /dev/null
+++ b/sync.cc
@@ -0,0 +1,105 @@
+#include "externals.hh"
+#include "sync.hh"
+
+
+const T_SyncVariable T_SyncData::MissingVariable_{ };
+
+
+T_SyncData::T_SyncData(
+		__rd__ const uint32_t duration ,
+		__rd__ const float units ) noexcept
+	: duration_( duration ) , units_( units )
+{ }
+
+
+T_SyncData::T_VarHelper_::T_VarHelper_(
+		__rw__ T_SyncVariable&& v ,
+		__rd__ const uint32_t duration ) noexcept
+	: variable( std::move( v ) )
+{
+	const auto n( variable.size( ) );
+	uint32_t s = 0;
+	for ( auto i = 0u ; i < n ; i ++ ) {
+		auto const& v( variable[ i ] );
+		assert( v.nPoints >= 2 );
+		assert( v.durations.size( ) == v.nPoints - 1 );
+
+		const auto nd( v.nPoints - 1 );
+		for ( auto j = 0u ; j < nd ; j ++ ) {
+			segStarts.push_back( s );
+			segRefs.push_back( std::make_pair( i , j ) );
+			s += v.durations[ j ];
+			if ( s > duration ) {
+				return;
+			}
+		}
+	}
+}
+
+
+void T_SyncData::setSyncVariable(
+		__rd__ std::string const& name ,
+		__rw__ T_SyncVariable&& variable ) noexcept
+{
+	variables_.erase( name );
+	if ( !variable.empty( ) ) {
+		variables_.emplace( name , T_VarHelper_{ std::move( variable ) , duration_ } );
+	}
+}
+
+
+T_SyncVariable const& T_SyncData::variable(
+	__rd__ std::string const& name ) const noexcept
+{
+	auto pos( variables_.find( name ) );
+	if ( pos == variables_.end( ) ) {
+		return MissingVariable_;
+	}
+	return pos->second.variable;
+}
+
+
+float T_SyncData::valueOf(
+	__rd__ std::string const& name ,
+	__rd__ const float time ) const noexcept
+{
+	assert( time >= 0 );
+
+	auto pos( variables_.find( name ) );
+	if ( pos == variables_.end( ) ) {
+		return 0;
+	}
+
+	// Find segment
+	auto const& var( pos->second );
+	const uint32_t tu( std::min( duration_ ,
+			uint32_t( floor( time / units_ ) ) ) );
+	uint32_t s( 0 );
+	for ( auto ss : var.segStarts ) {
+		if ( ss > tu ) {
+			break;
+		}
+		s ++;
+	}
+	assert( s > 0 );
+	s --;
+	const auto sid( var.segRefs[ s ].first );
+	auto const& seg( var.variable[ sid ] );
+	const auto pid( var.segRefs[ s ].second );
+	
+	// Interpolation factor
+	const float st( var.segStarts[ s ] * units_ );
+	const float et( ( var.segStarts[ s ] + seg.durations[ pid ] ) * units_ );
+	const float v0 = ( time - st ) / ( et - st );
+	float v = v0;
+	if ( seg.type != E_SyncSegment::LINEAR ) {
+		v *= v0;
+		if ( seg.type == E_SyncSegment::SMOOTH ) {
+			v *= 3 - 2 * v0;
+		}
+	}
+
+	const float sv( seg.values[ pid ] );
+	const float ev( seg.values[ pid + 1 ] );
+	return v * ( ev - sv ) + sv;
+}
diff --git a/sync.hh b/sync.hh
new file mode 100644
index 0000000..7286efc
--- /dev/null
+++ b/sync.hh
@@ -0,0 +1,63 @@
+#pragma once
+#ifndef REAL_BUILD
+# include "externals.hh"
+#endif
+
+
+enum class E_SyncSegment
+{
+	LINEAR ,
+	RAMP ,
+	SMOOTH ,
+	//HERMITE
+};
+
+struct T_SyncSegment
+{
+	uint32_t nPoints;
+	E_SyncSegment type;
+	std::vector< float > values;		// nPoints items
+	std::vector< uint32_t > durations;	// nPoints - 1 items
+};
+
+using T_SyncVariable = std::vector< T_SyncSegment >;
+
+
+struct T_SyncData
+{
+	T_SyncData( ) = delete;
+	T_SyncData(
+		__rd__ const uint32_t duration ,
+		__rd__ const float units ) noexcept;
+
+	void setSyncVariable(
+		__rd__ std::string const& name ,
+		__rw__ T_SyncVariable&& variable ) noexcept;
+
+	T_SyncVariable const& variable(
+		__rd__ std::string const& name ) const noexcept;
+
+	float valueOf(
+		__rd__ std::string const& variable ,
+		__rd__ const float time ) const noexcept;
+
+    private:
+	static const T_SyncVariable MissingVariable_;
+
+	// Caching structure used to access segments
+	using T_SegRef_ = std::pair< uint32_t , uint32_t >;
+	struct T_VarHelper_
+	{
+		T_SyncVariable variable;
+		std::vector< T_SegRef_ > segRefs;
+		std::vector< float > segStarts;
+
+		T_VarHelper_(
+			__rw__ T_SyncVariable&& variable ,
+			__rd__ const uint32_t duration ) noexcept;
+	};
+
+	uint32_t duration_;
+	float units_;
+	std::unordered_map< std::string , T_VarHelper_ > variables_;
+};