Don't allocate in Vector's ctor

By relying on the fact that a struct or class's first member has the
same address as the struct itself we can cast VectorWriteProxy<T> to
Vector<T> and access the CowData field.

This allows a Vector to be moved in memory without invalidating the
pointer to the cowdata field.
This commit is contained in:
Hein-Pieter van Braam 2018-12-14 20:03:02 +00:00
parent 7ac67bfec1
commit 3ef7ecf546
1 changed files with 23 additions and 33 deletions

View File

@ -44,17 +44,11 @@
template <class T>
class VectorWriteProxy {
friend class Vector<T>;
CowData<T> *_parent;
_FORCE_INLINE_ VectorWriteProxy(CowData<T> *parent) :
_parent(parent){};
public:
_FORCE_INLINE_ T &operator[](int p_index) {
CRASH_BAD_INDEX(p_index, _parent->size());
CRASH_BAD_INDEX(p_index, ((Vector<T> *)(this))->_cowdata.size());
return _parent->ptrw()[p_index];
return ((Vector<T> *)(this))->_cowdata.ptrw()[p_index];
}
};
@ -62,39 +56,41 @@ template <class T>
class Vector {
friend class VectorWriteProxy<T>;
CowData<T> *_cowdata;
public:
VectorWriteProxy<T> write;
private:
CowData<T> _cowdata;
public:
bool push_back(const T &p_elem);
void remove(int p_index) { _cowdata->remove(p_index); }
void remove(int p_index) { _cowdata.remove(p_index); }
void erase(const T &p_val) {
int idx = find(p_val);
if (idx >= 0) remove(idx);
};
void invert();
_FORCE_INLINE_ T *ptrw() { return _cowdata->ptrw(); }
_FORCE_INLINE_ const T *ptr() const { return _cowdata->ptr(); }
_FORCE_INLINE_ T *ptrw() { return _cowdata.ptrw(); }
_FORCE_INLINE_ const T *ptr() const { return _cowdata.ptr(); }
_FORCE_INLINE_ void clear() { resize(0); }
_FORCE_INLINE_ bool empty() const { return _cowdata->empty(); }
_FORCE_INLINE_ bool empty() const { return _cowdata.empty(); }
_FORCE_INLINE_ T get(int p_index) { return _cowdata->get(p_index); }
_FORCE_INLINE_ const T get(int p_index) const { return _cowdata->get(p_index); }
_FORCE_INLINE_ void set(int p_index, const T &p_elem) { _cowdata->set(p_index, p_elem); }
_FORCE_INLINE_ int size() const { return _cowdata->size(); }
Error resize(int p_size) { return _cowdata->resize(p_size); }
_FORCE_INLINE_ const T &operator[](int p_index) const { return _cowdata->get(p_index); }
Error insert(int p_pos, const T &p_val) { return _cowdata->insert(p_pos, p_val); }
_FORCE_INLINE_ T get(int p_index) { return _cowdata.get(p_index); }
_FORCE_INLINE_ const T get(int p_index) const { return _cowdata.get(p_index); }
_FORCE_INLINE_ void set(int p_index, const T &p_elem) { _cowdata.set(p_index, p_elem); }
_FORCE_INLINE_ int size() const { return _cowdata.size(); }
Error resize(int p_size) { return _cowdata.resize(p_size); }
_FORCE_INLINE_ const T &operator[](int p_index) const { return _cowdata.get(p_index); }
Error insert(int p_pos, const T &p_val) { return _cowdata.insert(p_pos, p_val); }
void append_array(const Vector<T> &p_other);
template <class C>
void sort_custom() {
int len = _cowdata->size();
int len = _cowdata.size();
if (len == 0)
return;
@ -110,7 +106,7 @@ public:
void ordered_insert(const T &p_val) {
int i;
for (i = 0; i < _cowdata->size(); i++) {
for (i = 0; i < _cowdata.size(); i++) {
if (p_val < operator[](i)) {
break;
@ -135,20 +131,14 @@ public:
return ret;
}
_FORCE_INLINE_ Vector() :
_cowdata(new CowData<T>()),
write(VectorWriteProxy<T>(_cowdata)) {}
_FORCE_INLINE_ Vector(const Vector &p_from) :
_cowdata(new CowData<T>()),
write(VectorWriteProxy<T>(_cowdata)) { _cowdata->_ref(p_from._cowdata); }
_FORCE_INLINE_ Vector() {}
_FORCE_INLINE_ Vector(const Vector &p_from) { _cowdata._ref(p_from._cowdata); }
inline Vector &operator=(const Vector &p_from) {
_cowdata->_ref(p_from._cowdata);
_cowdata._ref(p_from._cowdata);
return *this;
}
_FORCE_INLINE_ ~Vector() {
delete _cowdata;
}
_FORCE_INLINE_ ~Vector() {}
};
template <class T>