public void ReleaseAndMerge(AtlasNodePool pool)
{
Int16 n = m_Self;
do
{
pool.m_Nodes[n].ReleaseChildren(pool);
pool.m_Nodes[n].ClearIsOccupied();
n = pool.m_Nodes[n].m_Parent;
}while (n >= 0 && pool.m_Nodes[n].IsMergeNeeded(pool));
}
public void ReleaseChildren(AtlasNodePool pool)
{
if (IsLeafNode())
{
return;
}
pool.m_Nodes[m_LeftChild].ReleaseChildren(pool);
pool.m_Nodes[m_RightChild].ReleaseChildren(pool);
pool.AtlasNodeFree(m_LeftChild);
pool.AtlasNodeFree(m_RightChild);
m_LeftChild = -1;
m_RightChild = -1;
}
public AtlasAllocatorDynamic(int width, int height, int capacityAllocations)
{
// In an evenly split binary tree, the nodeCount == leafNodeCount * 2
int capacityNodes = capacityAllocations * 2;
Debug.Assert(capacityNodes < (1 << 16), "Error: AtlasAllocatorDynamic: Attempted to allocate a capacity of " + capacityNodes + ", which is greater than our 16-bit indices can support. Please request a capacity <=" + (1 << 16));
m_Pool = new AtlasNodePool((Int16)capacityNodes);
m_NodeFromID = new Dictionary <int, Int16>(capacityAllocations);
Int16 rootParent = -1;
m_Root = m_Pool.AtlasNodeCreate(rootParent);
m_Pool.m_Nodes[m_Root].m_Rect.Set(width, height, 0, 0);
m_Width = width;
m_Height = height;
// string debug = "";
// DebugStringFromNode(ref debug, m_Root);
// Debug.Log("Allocating atlas = " + debug);
}
public bool IsMergeNeeded(AtlasNodePool pool)
{
return(pool.m_Nodes[m_LeftChild].IsLeafNode() && (!pool.m_Nodes[m_LeftChild].IsOccupied()) &&
pool.m_Nodes[m_RightChild].IsLeafNode() && (!pool.m_Nodes[m_RightChild].IsOccupied()));
}
public Int16 Allocate(AtlasNodePool pool, int width, int height)
{
if (Mathf.Min(width, height) < 1)
{
// Degenerate allocation requested.
Debug.Assert(false, "Error: Texture2DAtlasDynamic: Attempted to allocate a degenerate region. Please ensure width and height are >= 1");
return(-1);
}
// not a leaf node, try children
// TODO: Rather than always going left, then right, we might want to always attempt to allocate in the smaller child, then larger.
if (!IsLeafNode())
{
Int16 node = pool.m_Nodes[m_LeftChild].Allocate(pool, width, height);
if (node == -1)
{
node = pool.m_Nodes[m_RightChild].Allocate(pool, width, height);
}
return(node);
}
// leaf node, check for fit
if (IsOccupied())
{
return(-1);
}
if (width > m_Rect.x || height > m_Rect.y)
{
return(-1);
}
// perform the split
Debug.Assert(m_LeftChild == -1);
Debug.Assert(m_RightChild == -1);
m_LeftChild = pool.AtlasNodeCreate(m_Self);
m_RightChild = pool.AtlasNodeCreate(m_Self);
// Debug.Log("m_LeftChild = " + m_LeftChild);
// Debug.Log("m_RightChild = " + m_RightChild);
Debug.Assert(m_LeftChild >= 0 && m_LeftChild < pool.m_Nodes.Length);
Debug.Assert(m_RightChild >= 0 && m_RightChild < pool.m_Nodes.Length);
// Debug.Log("Rect = {" + m_Rect.x + ", " + m_Rect.y + ", " + m_Rect.z + ", " + m_Rect.w + "}");
float deltaX = m_Rect.x - width;
float deltaY = m_Rect.y - height;
// Debug.Log("deltaX = " + deltaX);
// Debug.Log("deltaY = " + deltaY);
if (deltaX >= deltaY)
{
// Debug.Log("Split horizontally");
// +--------+------+
// | | |
// | | |
// | | |
// | | |
// +--------+------+
pool.m_Nodes[m_LeftChild].m_Rect.x = width;
pool.m_Nodes[m_LeftChild].m_Rect.y = m_Rect.y;
pool.m_Nodes[m_LeftChild].m_Rect.z = m_Rect.z;
pool.m_Nodes[m_LeftChild].m_Rect.w = m_Rect.w;
pool.m_Nodes[m_RightChild].m_Rect.x = deltaX;
pool.m_Nodes[m_RightChild].m_Rect.y = m_Rect.y;
pool.m_Nodes[m_RightChild].m_Rect.z = m_Rect.z + width;
pool.m_Nodes[m_RightChild].m_Rect.w = m_Rect.w;
if (deltaY < 1)
{
pool.m_Nodes[m_LeftChild].SetIsOccupied();
return(m_LeftChild);
}
else
{
Int16 node = pool.m_Nodes[m_LeftChild].Allocate(pool, width, height);
if (node >= 0)
{
pool.m_Nodes[node].SetIsOccupied();
}
return(node);
}
}
else
{
// Debug.Log("Split vertically.");
// +---------------+
// | |
// |---------------|
// | |
// | |
// +---------------+
pool.m_Nodes[m_LeftChild].m_Rect.x = m_Rect.x;
pool.m_Nodes[m_LeftChild].m_Rect.y = height;
pool.m_Nodes[m_LeftChild].m_Rect.z = m_Rect.z;
pool.m_Nodes[m_LeftChild].m_Rect.w = m_Rect.w;
pool.m_Nodes[m_RightChild].m_Rect.x = m_Rect.x;
pool.m_Nodes[m_RightChild].m_Rect.y = deltaY;
pool.m_Nodes[m_RightChild].m_Rect.z = m_Rect.z;
pool.m_Nodes[m_RightChild].m_Rect.w = m_Rect.w + height;
if (deltaX < 1)
{
pool.m_Nodes[m_LeftChild].SetIsOccupied();
return(m_LeftChild);
}
else
{
Int16 node = pool.m_Nodes[m_LeftChild].Allocate(pool, width, height);
if (node >= 0)
{
pool.m_Nodes[node].SetIsOccupied();
}
return(node);
}
}
}
