initial commit, 4.5 stable

thirdparty/jolt_physics/Jolt/Core/Array.h

@@ -0,0 +1,713 @@
+// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
+// SPDX-FileCopyrightText: 2024 Jorrit Rouwe
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+#include <Jolt/Core/STLAllocator.h>
+#include <Jolt/Core/HashCombine.h>
+
+#ifdef JPH_USE_STD_VECTOR
+
+JPH_SUPPRESS_WARNINGS_STD_BEGIN
+#include <vector>
+JPH_SUPPRESS_WARNINGS_STD_END
+
+JPH_NAMESPACE_BEGIN
+
+template <class T, class Allocator = STLAllocator<T>> using Array = std::vector<T, Allocator>;
+
+JPH_NAMESPACE_END
+
+#else
+
+JPH_NAMESPACE_BEGIN
+
+/// Simple replacement for std::vector
+///
+/// Major differences:
+/// - Memory is not initialized to zero (this was causing a lot of page faults when deserializing large MeshShapes / HeightFieldShapes)
+/// - Iterators are simple pointers (for now)
+/// - No exception safety
+/// - No specialization like std::vector<bool> has
+/// - Not all functions have been implemented
+template <class T, class Allocator = STLAllocator<T>>
+class [[nodiscard]] Array : private Allocator
+{
+public:
+	using value_type = T;
+	using allocator_type = Allocator;
+	using size_type = size_t;
+	using difference_type = typename Allocator::difference_type;
+	using pointer = T *;
+	using const_pointer = const T *;
+	using reference = T &;
+	using const_reference = const T &;
+
+	using const_iterator = const T *;
+	using iterator = T *;
+
+	/// An iterator that traverses the array in reverse order
+	class rev_it
+	{
+	public:
+		/// Constructor
+							rev_it() = default;
+		explicit			rev_it(T *inValue)				: mValue(inValue) { }
+
+		/// Copying
+							rev_it(const rev_it &) = default;
+		rev_it &			operator = (const rev_it &) = default;
+
+		/// Comparison
+		bool				operator == (const rev_it &inRHS) const { return mValue == inRHS.mValue; }
+		bool				operator != (const rev_it &inRHS) const { return mValue != inRHS.mValue; }
+
+		/// Arithmetics
+		rev_it &			operator ++ ()					{ --mValue; return *this; }
+		rev_it				operator ++ (int)				{ return rev_it(mValue--); }
+		rev_it &			operator -- ()					{ ++mValue; return *this; }
+		rev_it				operator -- (int)				{ return rev_it(mValue++); }
+
+		rev_it				operator + (int inValue)		{ return rev_it(mValue - inValue); }
+		rev_it				operator - (int inValue)		{ return rev_it(mValue + inValue); }
+
+		rev_it &			operator += (int inValue)		{ mValue -= inValue; return *this; }
+		rev_it &			operator -= (int inValue)		{ mValue += inValue; return *this; }
+
+		/// Access
+		T &					operator * () const				{ return *mValue; }
+		T &					operator -> () const			{ return *mValue; }
+
+	private:
+		T *					mValue;
+	};
+
+	/// A const iterator that traverses the array in reverse order
+	class crev_it
+	{
+	public:
+		/// Constructor
+							crev_it() = default;
+		explicit			crev_it(const T *inValue)		: mValue(inValue) { }
+
+		/// Copying
+							crev_it(const crev_it &) = default;
+		explicit			crev_it(const rev_it &inValue)	: mValue(inValue.mValue) { }
+		crev_it &			operator = (const crev_it &) = default;
+		crev_it &			operator = (const rev_it &inRHS) { mValue = inRHS.mValue; return *this; }
+
+		/// Comparison
+		bool				operator == (const crev_it &inRHS) const { return mValue == inRHS.mValue; }
+		bool				operator != (const crev_it &inRHS) const { return mValue != inRHS.mValue; }
+
+		/// Arithmetics
+		crev_it &			operator ++ ()					{ --mValue; return *this; }
+		crev_it				operator ++ (int)				{ return crev_it(mValue--); }
+		crev_it &			operator -- ()					{ ++mValue; return *this; }
+		crev_it				operator -- (int)				{ return crev_it(mValue++); }
+
+		crev_it				operator + (int inValue)		{ return crev_it(mValue - inValue); }
+		crev_it				operator - (int inValue)		{ return crev_it(mValue + inValue); }
+
+		crev_it &			operator += (int inValue)		{ mValue -= inValue; return *this; }
+		crev_it &			operator -= (int inValue)		{ mValue += inValue; return *this; }
+
+		/// Access
+		const T &			operator * () const				{ return *mValue; }
+		const T &			operator -> () const			{ return *mValue; }
+
+	private:
+		const T *			mValue;
+	};
+
+	using reverse_iterator = rev_it;
+	using const_reverse_iterator = crev_it;
+
+private:
+	/// Move elements from one location to another
+	inline void				move(pointer inDestination, pointer inSource, size_type inCount)
+	{
+		if constexpr (std::is_trivially_copyable<T>())
+			memmove(inDestination, inSource, inCount * sizeof(T));
+		else
+		{
+			if (inDestination < inSource)
+			{
+				for (T *destination_end = inDestination + inCount; inDestination < destination_end; ++inDestination, ++inSource)
+				{
+					new (inDestination) T(std::move(*inSource));
+					inSource->~T();
+				}
+			}
+			else
+			{
+				for (T *destination = inDestination + inCount - 1, *source = inSource + inCount - 1; destination >= inDestination; --destination, --source)
+				{
+					new (destination) T(std::move(*source));
+					source->~T();
+				}
+			}
+		}
+	}
+
+	/// Reallocate the data block to inNewCapacity
+	inline void				reallocate(size_type inNewCapacity)
+	{
+		JPH_ASSERT(inNewCapacity > 0 && inNewCapacity >= mSize);
+
+		pointer ptr;
+		if constexpr (AllocatorHasReallocate<Allocator>::sValue)
+		{
+			// Reallocate data block
+			ptr = get_allocator().reallocate(mElements, mCapacity, inNewCapacity);
+		}
+		else
+		{
+			// Copy data to a new location
+			ptr = get_allocator().allocate(inNewCapacity);
+			if (mElements != nullptr)
+			{
+				move(ptr, mElements, mSize);
+				get_allocator().deallocate(mElements, mCapacity);
+			}
+		}
+		mElements = ptr;
+		mCapacity = inNewCapacity;
+	}
+
+	/// Destruct elements [inStart, inEnd - 1]
+	inline void				destruct(size_type inStart, size_type inEnd)
+	{
+		if constexpr (!std::is_trivially_destructible<T>())
+			if (inStart < inEnd)
+				for (T *element = mElements + inStart, *element_end = mElements + inEnd; element < element_end; ++element)
+					element->~T();
+	}
+
+public:
+	/// Reserve array space
+	inline void				reserve(size_type inNewSize)
+	{
+		if (mCapacity < inNewSize)
+			reallocate(inNewSize);
+	}
+
+	/// Resize array to new length
+	inline void				resize(size_type inNewSize)
+	{
+		destruct(inNewSize, mSize);
+		reserve(inNewSize);
+
+		if constexpr (!std::is_trivially_constructible<T>())
+			for (T *element = mElements + mSize, *element_end = mElements + inNewSize; element < element_end; ++element)
+				new (element) T;
+		mSize = inNewSize;
+	}
+
+	/// Resize array to new length and initialize all elements with inValue
+	inline void				resize(size_type inNewSize, const T &inValue)
+	{
+		JPH_ASSERT(&inValue < mElements || &inValue >= mElements + mSize, "Can't pass an element from the array to resize");
+
+		destruct(inNewSize, mSize);
+		reserve(inNewSize);
+
+		for (T *element = mElements + mSize, *element_end = mElements + inNewSize; element < element_end; ++element)
+			new (element) T(inValue);
+		mSize = inNewSize;
+	}
+
+	/// Destruct all elements and set length to zero
+	inline void				clear()
+	{
+		destruct(0, mSize);
+		mSize = 0;
+	}
+
+private:
+	/// Grow the array by at least inAmount elements
+	inline void				grow(size_type inAmount = 1)
+	{
+		size_type min_size = mSize + inAmount;
+		if (min_size > mCapacity)
+		{
+			size_type new_capacity = max(min_size, mCapacity * 2);
+			reserve(new_capacity);
+		}
+	}
+
+	/// Free memory
+	inline void				free()
+	{
+		get_allocator().deallocate(mElements, mCapacity);
+		mElements = nullptr;
+		mCapacity = 0;
+	}
+
+	/// Destroy all elements and free memory
+	inline void				destroy()
+	{
+		if (mElements != nullptr)
+		{
+			clear();
+			free();
+		}
+	}
+
+public:
+	/// Replace the contents of this array with inBegin .. inEnd
+	template <class Iterator>
+	inline void				assign(Iterator inBegin, Iterator inEnd)
+	{
+		clear();
+		reserve(size_type(std::distance(inBegin, inEnd)));
+
+		for (Iterator element = inBegin; element != inEnd; ++element)
+			new (&mElements[mSize++]) T(*element);
+	}
+
+	/// Replace the contents of this array with inList
+	inline void				assign(std::initializer_list<T> inList)
+	{
+		clear();
+		reserve(size_type(inList.size()));
+
+		for (const T &v : inList)
+			new (&mElements[mSize++]) T(v);
+	}
+
+	/// Default constructor
+							Array() = default;
+
+	/// Constructor with allocator
+	explicit inline			Array(const Allocator &inAllocator) :
+		Allocator(inAllocator)
+	{
+	}
+
+	/// Constructor with length
+	explicit inline			Array(size_type inLength, const Allocator &inAllocator = { }) :
+		Allocator(inAllocator)
+	{
+		resize(inLength);
+	}
+
+	/// Constructor with length and value
+	inline					Array(size_type inLength, const T &inValue, const Allocator &inAllocator = { }) :
+		Allocator(inAllocator)
+	{
+		resize(inLength, inValue);
+	}
+
+	/// Constructor from initializer list
+	inline					Array(std::initializer_list<T> inList, const Allocator &inAllocator = { }) :
+		Allocator(inAllocator)
+	{
+		assign(inList);
+	}
+
+	/// Constructor from iterator
+	inline					Array(const_iterator inBegin, const_iterator inEnd, const Allocator &inAllocator = { }) :
+		Allocator(inAllocator)
+	{
+		assign(inBegin, inEnd);
+	}
+
+	/// Copy constructor
+	inline					Array(const Array<T, Allocator> &inRHS) :
+		Allocator(inRHS.get_allocator())
+	{
+		assign(inRHS.begin(), inRHS.end());
+	}
+
+	/// Move constructor
+	inline					Array(Array<T, Allocator> &&inRHS) noexcept :
+		Allocator(std::move(inRHS.get_allocator())),
+		mSize(inRHS.mSize),
+		mCapacity(inRHS.mCapacity),
+		mElements(inRHS.mElements)
+	{
+		inRHS.mSize = 0;
+		inRHS.mCapacity = 0;
+		inRHS.mElements = nullptr;
+	}
+
+	/// Destruct all elements
+	inline					~Array()
+	{
+		destroy();
+	}
+
+	/// Get the allocator
+	inline Allocator &		get_allocator()
+	{
+		return *this;
+	}
+
+	inline const Allocator &get_allocator() const
+	{
+		return *this;
+	}
+
+	/// Add element to the back of the array
+	inline void				push_back(const T &inValue)
+	{
+		JPH_ASSERT(&inValue < mElements || &inValue >= mElements + mSize, "Can't pass an element from the array to push_back");
+
+		grow();
+
+		T *element = mElements + mSize++;
+		new (element) T(inValue);
+	}
+
+	inline void				push_back(T &&inValue)
+	{
+		grow();
+
+		T *element = mElements + mSize++;
+		new (element) T(std::move(inValue));
+	}
+
+	/// Construct element at the back of the array
+	template <class... A>
+	inline T &				emplace_back(A &&... inValue)
+	{
+		grow();
+
+		T *element = mElements + mSize++;
+		new (element) T(std::forward<A>(inValue)...);
+		return *element;
+	}
+
+	/// Remove element from the back of the array
+	inline void				pop_back()
+	{
+		JPH_ASSERT(mSize > 0);
+		mElements[--mSize].~T();
+	}
+
+	/// Returns true if there are no elements in the array
+	inline bool				empty() const
+	{
+		return mSize == 0;
+	}
+
+	/// Returns amount of elements in the array
+	inline size_type		size() const
+	{
+		return mSize;
+	}
+
+	/// Returns maximum amount of elements the array can hold
+	inline size_type		capacity() const
+	{
+		return mCapacity;
+	}
+
+	/// Reduce the capacity of the array to match its size
+	void					shrink_to_fit()
+	{
+		if (mElements != nullptr)
+		{
+			if (mSize == 0)
+				free();
+			else if (mCapacity > mSize)
+				reallocate(mSize);
+		}
+	}
+
+	/// Swap the contents of two arrays
+	void					swap(Array<T, Allocator> &inRHS) noexcept
+	{
+		std::swap(get_allocator(), inRHS.get_allocator());
+		std::swap(mSize, inRHS.mSize);
+		std::swap(mCapacity, inRHS.mCapacity);
+		std::swap(mElements, inRHS.mElements);
+	}
+
+	template <class Iterator>
+	void					insert(const_iterator inPos, Iterator inBegin, Iterator inEnd)
+	{
+		size_type num_elements = size_type(std::distance(inBegin, inEnd));
+		if (num_elements > 0)
+		{
+			// After grow() inPos may be invalid
+			size_type first_element = inPos - mElements;
+
+			grow(num_elements);
+
+			T *element_begin = mElements + first_element;
+			T *element_end = element_begin + num_elements;
+			move(element_end, element_begin, mSize - first_element);
+
+			for (T *element = element_begin; element < element_end; ++element, ++inBegin)
+				new (element) T(*inBegin);
+
+			mSize += num_elements;
+		}
+	}
+
+	void					insert(const_iterator inPos, const T &inValue)
+	{
+		JPH_ASSERT(&inValue < mElements || &inValue >= mElements + mSize, "Can't pass an element from the array to insert");
+
+		// After grow() inPos may be invalid
+		size_type first_element = inPos - mElements;
+
+		grow();
+
+		T *element = mElements + first_element;
+		move(element + 1, element, mSize - first_element);
+
+		new (element) T(inValue);
+		mSize++;
+	}
+
+	/// Remove one element from the array
+	iterator				erase(const_iterator inIter)
+	{
+		size_type p = size_type(inIter - begin());
+		JPH_ASSERT(p < mSize);
+		mElements[p].~T();
+		if (p + 1 < mSize)
+			move(mElements + p, mElements + p + 1, mSize - p - 1);
+		--mSize;
+		return const_cast<iterator>(inIter);
+	}
+
+	/// Remove multiple element from the array
+	iterator				erase(const_iterator inBegin, const_iterator inEnd)
+	{
+		size_type p = size_type(inBegin - begin());
+		size_type n = size_type(inEnd - inBegin);
+		JPH_ASSERT(inEnd <= end());
+		destruct(p, p + n);
+		if (p + n < mSize)
+			move(mElements + p, mElements + p + n, mSize - p - n);
+		mSize -= n;
+		return const_cast<iterator>(inBegin);
+	}
+
+	/// Iterators
+	inline const_iterator	begin() const
+	{
+		return mElements;
+	}
+
+	inline const_iterator	end() const
+	{
+		return mElements + mSize;
+	}
+
+	inline crev_it			rbegin() const
+	{
+		return crev_it(mElements + mSize - 1);
+	}
+
+	inline crev_it			rend() const
+	{
+		return crev_it(mElements - 1);
+	}
+
+	inline const_iterator	cbegin() const
+	{
+		return begin();
+	}
+
+	inline const_iterator	cend() const
+	{
+		return end();
+	}
+
+	inline crev_it			crbegin() const
+	{
+		return rbegin();
+	}
+
+	inline crev_it			crend() const
+	{
+		return rend();
+	}
+
+	inline iterator			begin()
+	{
+		return mElements;
+	}
+
+	inline iterator			end()
+	{
+		return mElements + mSize;
+	}
+
+	inline rev_it			rbegin()
+	{
+		return rev_it(mElements + mSize - 1);
+	}
+
+	inline rev_it			rend()
+	{
+		return rev_it(mElements - 1);
+	}
+
+	inline const T *		data() const
+	{
+		return mElements;
+	}
+
+	inline T *				data()
+	{
+		return mElements;
+	}
+
+	/// Access element
+	inline T &				operator [] (size_type inIdx)
+	{
+		JPH_ASSERT(inIdx < mSize);
+		return mElements[inIdx];
+	}
+
+	inline const T &		operator [] (size_type inIdx) const
+	{
+		JPH_ASSERT(inIdx < mSize);
+		return mElements[inIdx];
+	}
+
+	/// Access element
+	inline T &				at(size_type inIdx)
+	{
+		JPH_ASSERT(inIdx < mSize);
+		return mElements[inIdx];
+	}
+
+	inline const T &		at(size_type inIdx) const
+	{
+		JPH_ASSERT(inIdx < mSize);
+		return mElements[inIdx];
+	}
+
+	/// First element in the array
+	inline const T &		front() const
+	{
+		JPH_ASSERT(mSize > 0);
+		return mElements[0];
+	}
+
+	inline T &				front()
+	{
+		JPH_ASSERT(mSize > 0);
+		return mElements[0];
+	}
+
+	/// Last element in the array
+	inline const T &		back() const
+	{
+		JPH_ASSERT(mSize > 0);
+		return mElements[mSize - 1];
+	}
+
+	inline T &				back()
+	{
+		JPH_ASSERT(mSize > 0);
+		return mElements[mSize - 1];
+	}
+
+	/// Assignment operator
+	Array<T, Allocator> &	operator = (const Array<T, Allocator> &inRHS)
+	{
+		if (static_cast<const void *>(this) != static_cast<const void *>(&inRHS))
+			assign(inRHS.begin(), inRHS.end());
+
+		return *this;
+	}
+
+	/// Assignment move operator
+	Array<T, Allocator> &	operator = (Array<T, Allocator> &&inRHS) noexcept
+	{
+		if (static_cast<const void *>(this) != static_cast<const void *>(&inRHS))
+		{
+			destroy();
+
+			get_allocator() = std::move(inRHS.get_allocator());
+
+			mSize = inRHS.mSize;
+			mCapacity = inRHS.mCapacity;
+			mElements = inRHS.mElements;
+
+			inRHS.mSize = 0;
+			inRHS.mCapacity = 0;
+			inRHS.mElements = nullptr;
+		}
+
+		return *this;
+	}
+
+	/// Assignment operator
+	Array<T, Allocator> &	operator = (std::initializer_list<T> inRHS)
+	{
+		assign(inRHS);
+
+		return *this;
+	}
+
+	/// Comparing arrays
+	bool					operator == (const Array<T, Allocator> &inRHS) const
+	{
+		if (mSize != inRHS.mSize)
+			return false;
+		for (size_type i = 0; i < mSize; ++i)
+			if (!(mElements[i] == inRHS.mElements[i]))
+				return false;
+		return true;
+	}
+
+	bool					operator != (const Array<T, Allocator> &inRHS) const
+	{
+		if (mSize != inRHS.mSize)
+			return true;
+		for (size_type i = 0; i < mSize; ++i)
+			if (mElements[i] != inRHS.mElements[i])
+				return true;
+		return false;
+	}
+
+	/// Get hash for this array
+	uint64					GetHash() const
+	{
+		// Hash length first
+		uint64 ret = Hash<uint32> { } (uint32(size()));
+
+		// Then hash elements
+		for (const T *element = mElements, *element_end = mElements + mSize; element < element_end; ++element)
+			HashCombine(ret, *element);
+
+		return ret;
+	}
+
+private:
+	size_type				mSize = 0;
+	size_type				mCapacity = 0;
+	T *						mElements = nullptr;
+};
+
+JPH_NAMESPACE_END
+
+JPH_SUPPRESS_WARNING_PUSH
+JPH_CLANG_SUPPRESS_WARNING("-Wc++98-compat")
+
+namespace std
+{
+	/// Declare std::hash for Array
+	template <class T, class Allocator>
+	struct hash<JPH::Array<T, Allocator>>
+	{
+		size_t operator () (const JPH::Array<T, Allocator> &inRHS) const
+		{
+			return std::size_t(inRHS.GetHash());
+		}
+	};
+}
+
+JPH_SUPPRESS_WARNING_POP
+
+#endif // JPH_USE_STD_VECTOR