public void BuildTree(Deflater deflater)
{
short[] dynamicTree = this.dynamicTree;
short[] staticTreeData = this.staticTree.StaticTreeData;
int maxElements = this.staticTree.MaxElements;
int maxCode = -1;
deflater.heapLen = 0;
deflater.heapMax = TreeConstants.HeapSize;
for (int index = 0; index < maxElements; ++index)
{
if (dynamicTree[index * 2] != (short)0)
{
deflater.heap[++deflater.heapLen] = maxCode = index;
deflater.depth[index] = (byte)0;
}
else
{
dynamicTree[index * 2 + 1] = (short)0;
}
}
while (deflater.heapLen < 2)
{
int[] heap = deflater.heap;
int index1 = ++deflater.heapLen;
int num1;
if (maxCode >= 2)
{
num1 = 0;
}
else
{
maxCode = num1 = maxCode + 1;
}
int num2 = num1;
heap[index1] = num1;
int index2 = num2;
dynamicTree[index2 * 2] = (short)1;
deflater.depth[index2] = (byte)0;
--deflater.opt_len;
if (staticTreeData != null)
{
deflater.static_len -= (int)staticTreeData[index2 * 2 + 1];
}
}
this.maxCode = maxCode;
for (int k = deflater.heapLen / 2; k >= 1; --k)
{
deflater.RestoreHeapDown(dynamicTree, k);
}
int index3 = maxElements;
do
{
int index1 = deflater.heap[1];
deflater.heap[1] = deflater.heap[deflater.heapLen--];
deflater.RestoreHeapDown(dynamicTree, 1);
int index2 = deflater.heap[1];
deflater.heap[--deflater.heapMax] = index1;
deflater.heap[--deflater.heapMax] = index2;
dynamicTree[index3 * 2] = (short)((int)dynamicTree[index1 * 2] + (int)dynamicTree[index2 * 2]);
deflater.depth[index3] = (byte)((uint)Math.Max(deflater.depth[index1], deflater.depth[index2]) + 1U);
dynamicTree[index1 * 2 + 1] = dynamicTree[index2 * 2 + 1] = (short)index3;
deflater.heap[1] = index3++;
deflater.RestoreHeapDown(dynamicTree, 1);
}while (deflater.heapLen >= 2);
deflater.heap[--deflater.heapMax] = deflater.heap[1];
this.GenerateBitLengths(deflater);
CompressionTree.GenerateCodes(dynamicTree, maxCode, deflater.bl_count);
}