From ea71949e815683b3fbe603221dc8476254cf3c67 Mon Sep 17 00:00:00 2001
From: Pharap <2933055+Pharap@users.noreply.github.com>
Date: Fri, 26 Mar 2021 22:26:27 +0000
Subject: [PATCH] Add conversion operators for SFixed and UFixed (#93)

This will finally allow SFixed and UFixed to be converted to and from each other.
---
 src/FixedPoints/SFixed.h                |  8 ++++++++
 src/FixedPoints/SFixedMemberFunctions.h | 19 +++++++++++++++++++
 src/FixedPoints/UFixed.h                |  8 ++++++++
 src/FixedPoints/UFixedMemberFunctions.h | 19 +++++++++++++++++++
 4 files changed, 54 insertions(+)

diff --git a/src/FixedPoints/SFixed.h b/src/FixedPoints/SFixed.h
index 01c95f1..4d93cf7 100644
--- a/src/FixedPoints/SFixed.h
+++ b/src/FixedPoints/SFixed.h
@@ -22,6 +22,9 @@ FIXED_POINTS_BEGIN_NAMESPACE
 // Declaration
 //
 
+template< unsigned Integer, unsigned Fraction >
+class UFixed;
+
 template< unsigned Integer, unsigned Fraction >
 class SFixed
 {
@@ -103,6 +106,11 @@ public:
 	template< unsigned IntegerOut, unsigned FractionOut >
 	constexpr explicit operator SFixed<IntegerOut, FractionOut>() const;
 
+	template< unsigned IntegerOut, unsigned FractionOut >
+	constexpr explicit operator UFixed<IntegerOut, FractionOut>() const;
+
+	constexpr explicit operator UFixed<Integer + 1, Fraction>() const;
+
 	static constexpr SFixed fromInternal(const InternalType & value);
 
 	constexpr SFixed operator -() const;
diff --git a/src/FixedPoints/SFixedMemberFunctions.h b/src/FixedPoints/SFixedMemberFunctions.h
index 9d1268b..69f35e5 100644
--- a/src/FixedPoints/SFixedMemberFunctions.h
+++ b/src/FixedPoints/SFixedMemberFunctions.h
@@ -198,6 +198,25 @@ constexpr SFixed<Integer, Fraction>::operator SFixed<IntegerOut, FractionOut>()
 		OutputType::fromInternal(this->value);
 }
 
+template< unsigned Integer, unsigned Fraction >
+template< unsigned IntegerOut, unsigned FractionOut >
+constexpr SFixed<Integer, Fraction>::operator UFixed<IntegerOut, FractionOut>() const
+{
+	using OutputType = UFixed<IntegerOut, FractionOut>;
+	using IntermediaryType = SFixed<IntegerOut - 1, FractionOut>;
+
+	return static_cast<OutputType>(static_cast<IntermediaryType>(*this));
+}
+
+template< unsigned Integer, unsigned Fraction >
+constexpr SFixed<Integer, Fraction>::operator UFixed<Integer + 1, Fraction>() const
+{
+	using OutputType = UFixed<Integer + 1, Fraction>;
+	using OutputInternalType = typename OutputType::InternalType;
+	
+	return OutputType::fromInternal(static_cast<OutputInternalType>(this->value));
+}
+
 //
 // Static Functions
 //
diff --git a/src/FixedPoints/UFixed.h b/src/FixedPoints/UFixed.h
index 747996c..4444f55 100644
--- a/src/FixedPoints/UFixed.h
+++ b/src/FixedPoints/UFixed.h
@@ -22,6 +22,9 @@ FIXED_POINTS_BEGIN_NAMESPACE
 // Declaration
 //
 
+template< unsigned Integer, unsigned Fraction >
+class SFixed;
+
 template< unsigned Integer, unsigned Fraction >
 class UFixed
 {
@@ -104,6 +107,11 @@ public:
 	template< unsigned IntegerOut, unsigned FractionOut >
 	constexpr explicit operator UFixed<IntegerOut, FractionOut>() const;
 
+	template< unsigned IntegerOut, unsigned FractionOut >
+	constexpr explicit operator SFixed<IntegerOut, FractionOut>() const;
+
+	constexpr explicit operator SFixed<Integer - 1, Fraction>() const;
+
 	static constexpr UFixed fromInternal(const InternalType & value);
 
 	UFixed & operator ++();
diff --git a/src/FixedPoints/UFixedMemberFunctions.h b/src/FixedPoints/UFixedMemberFunctions.h
index 2540b9f..00def81 100644
--- a/src/FixedPoints/UFixedMemberFunctions.h
+++ b/src/FixedPoints/UFixedMemberFunctions.h
@@ -189,6 +189,25 @@ constexpr UFixed<Integer, Fraction>::operator UFixed<IntegerOut, FractionOut>()
 		OutputType::fromInternal(this->value);
 }
 
+template< unsigned Integer, unsigned Fraction >
+template< unsigned IntegerOut, unsigned FractionOut >
+constexpr UFixed<Integer, Fraction>::operator SFixed<IntegerOut, FractionOut>() const
+{
+	using OutputType = SFixed<IntegerOut, FractionOut>;
+	using IntermediaryType = UFixed<IntegerOut + 1, FractionOut>;
+
+	return static_cast<OutputType>(static_cast<IntermediaryType>(*this));
+}
+
+template< unsigned Integer, unsigned Fraction >
+constexpr UFixed<Integer, Fraction>::operator SFixed<Integer - 1, Fraction>() const
+{
+	using OutputType = SFixed<Integer - 1, Fraction>;
+	using OutputInternalType = typename OutputType::InternalType;
+	
+	return OutputType::fromInternal(static_cast<OutputInternalType>(this->value));
+}
+
 //
 // Static Functions
 //