private static void RemoveHashItem(ref DynamicBuffer <BufferHashSetElementData> hashMapBuffer, int hashMapIndex, int bufferIndex,
int bufferCapacity)
{
//get buffer element hash index
var currentItemHashIndex = GetHashItemIndex(ref hashMapBuffer, hashMapIndex, bufferIndex);
//get chain last item
var chainLastHashItemIndex = GetChainLastHashItemIndex(ref hashMapBuffer, hashMapIndex);
// if root item
if (currentItemHashIndex < bufferCapacity)
{
// single item chain
if (hashMapBuffer[hashMapIndex].NextItem < 0)
{
hashMapBuffer[hashMapIndex] = new BufferHashSetElementData(-1, true, -1, -1, hashMapBuffer[hashMapIndex].HashMapIndex);
}
else
{
RemoveHashItemInChain(ref hashMapBuffer, currentItemHashIndex, chainLastHashItemIndex);
MoveTailToAndCut(ref hashMapBuffer, chainLastHashItemIndex);
}
}
//if not root item
else
{
RemoveHashItemInChain(ref hashMapBuffer, currentItemHashIndex, chainLastHashItemIndex);
MoveTailToAndCut(ref hashMapBuffer, chainLastHashItemIndex);
}
}
private static void SetHashItemIndex(ref DynamicBuffer <BufferHashSetElementData> hashMapBuffer, int index, int bufferItemIndex)
{
var hashMapBufferIndex = hashMapBuffer[bufferItemIndex].HashMapIndex;
BufferHashSetElementData hashSetItem = hashMapBuffer[hashMapBufferIndex];
for (int i = 0; i < hashMapBuffer.Capacity; i++)
{
if (hashMapBuffer[hashMapBufferIndex].Index == bufferItemIndex)
{
break;
}
hashMapBufferIndex = hashMapBuffer[hashMapBufferIndex].NextItem;
hashSetItem = hashMapBuffer[hashMapBufferIndex];
}
hashSetItem.Index = index;
if (index < 0)
{
hashSetItem.Empty = true;
}
hashMapBuffer[hashMapBufferIndex] = hashSetItem;
}
private static void SetHashItemHashIndex(ref DynamicBuffer <BufferHashSetElementData> hashMapBuffer, int index, int bufferItemIndex)
{
BufferHashSetElementData hashSetItem = hashMapBuffer[bufferItemIndex];
hashSetItem.HashMapIndex = index;
hashMapBuffer[bufferItemIndex] = hashSetItem;
}
public static bool TryAdd <T>(DynamicBuffer <T> buffer, DynamicBuffer <BufferHashSetElementData> hashMapBuffer, T element)
where T : struct, IBufferElementData, IEqualityComparer <T>
{
if (buffer.Length >= buffer.Capacity)
{
Debug.Log("Error, buffer is full");
return(false);
}
int index = GetIndex(element, buffer.Capacity);
if (hashMapBuffer[index].Empty)
{
int newElementIndex = buffer.Add(element);
var hashMapBufferItem = hashMapBuffer[index];
hashMapBufferItem.Index = newElementIndex;
hashMapBufferItem.Empty = false;
hashMapBuffer[index] = hashMapBufferItem;
var hashMapItemByIndex = hashMapBuffer[newElementIndex];
hashMapItemByIndex.HashMapIndex = index;
hashMapBuffer[newElementIndex] = hashMapItemByIndex;
return(true);
}
int hashIndex = index;
int nextIndex = hashMapBuffer[hashIndex].NextItem;
for (int i = 0; i < buffer.Capacity; i++)
{
if (nextIndex < 0)
{
int newElementIndex = buffer.Add(element);
hashMapBuffer.Add(new BufferHashSetElementData(newElementIndex, false, hashIndex, -1, index));
hashMapBuffer[hashIndex] = new BufferHashSetElementData
(hashMapBuffer[hashIndex].Index, hashMapBuffer[hashIndex].Empty, hashMapBuffer[hashIndex].PrevItem, hashMapBuffer.Length - 1,
hashMapBuffer[hashIndex].HashMapIndex);
var hashMapItemByIndex = hashMapBuffer[newElementIndex];
hashMapItemByIndex.HashMapIndex = index;
hashMapBuffer[newElementIndex] = hashMapItemByIndex;
return(true);
}
if (hashMapBuffer[nextIndex].Empty)
{
int newElementIndex = buffer.Add(element);
hashMapBuffer.Add(new BufferHashSetElementData(newElementIndex, false, hashIndex, -1, index));
hashMapBuffer[hashIndex] = new BufferHashSetElementData
(hashMapBuffer[hashIndex].Index, hashMapBuffer[hashIndex].Empty, hashMapBuffer[hashIndex].PrevItem, hashMapBuffer.Length - 1,
hashMapBuffer[hashIndex].HashMapIndex);
var hashMapItemByIndex = hashMapBuffer[newElementIndex];
hashMapItemByIndex.HashMapIndex = index;
hashMapBuffer[newElementIndex] = hashMapItemByIndex;
return(true);
}
if (buffer[hashMapBuffer[nextIndex].Index].Equals(element, buffer[hashMapBuffer[nextIndex].Index]))
{
#if UNITY_EDITOR || DEBUG
Debug.Log("Already has item, add error::" + index);
#endif
return(false);
}
hashIndex = nextIndex;
nextIndex = hashMapBuffer[nextIndex].NextItem;
}
return(false);
}
