public void DecodeFrom( CompressedBlock block )
{
const int INVALID_ADJ = 15;
const int TERMINATOR = 128;
Install install = block.Parent.Install;
byte[] data = block.Data;
for ( int i=0; i<IDTABLE_SIZE; ++i ) idTable[i] = ushort.MaxValue;
int index = 0;
idCount = -1;
// Get a list of province ids
do {
++idCount;
idTable[idCount] = (ushort)(data[idCount<<1] + ((data[(idCount<<1)+1]&127) << 8));
index += 2;
} while ( data[(idCount<<1)+1] < TERMINATOR );
++idCount;
// Normalize the IDs... Basically, we're stripping some of that data away which we don't need (mainly to do with borders).
for ( int i=0; i<idCount; ++i ) {
if ( idTable[i] <= Province.MaxID ) continue;
ushort id = idTable[((idTable[i]>>9) & 63)-4];
if( id > Province.MaxID )
id = install.Provinces.TerraIncognita.ID;
else {
int river = (idTable[i]>>5) & 15;
if ( river != INVALID_ADJ ) id = install.Provinces[id].GetNeighbor( river ).ID;
idTable[i] = id;
}
}
// Build the tree.
DecompressorState decompstate = new DecompressorState( index, ref data );
BuildTree( root, decompstate, 5 );
index = decompstate.GetFinalNodeIndex();
// Define ownership and colors tables
int numLeaves = decompstate.NumOfLeaves;
int sizeLeaves = decompstate.SizeOfLeaves;
byte[] colors = new byte[decompstate.SizeOfLeaves + (4-(decompstate.SizeOfLeaves % 4))];
ushort[] ownership = null;
decompstate = null;
if ( idCount == 1 ) {
ownership = new ushort[numLeaves];
for ( int i=0; i<numLeaves; ++i )
ownership[i] = idTable[0];
}
else if ( idCount == 2 ) {
ownership = new ushort[numLeaves + (8-(numLeaves % 8))];
for ( int i=0; i<numLeaves; ++index ) {
ownership[i++] = idTable[(data[index] >> 0) & 1];
ownership[i++] = idTable[(data[index] >> 1) & 1];
ownership[i++] = idTable[(data[index] >> 2) & 1];
ownership[i++] = idTable[(data[index] >> 3) & 1];
ownership[i++] = idTable[(data[index] >> 4) & 1];
ownership[i++] = idTable[(data[index] >> 5) & 1];
ownership[i++] = idTable[(data[index] >> 6) & 1];
ownership[i++] = idTable[(data[index] >> 7) & 1];
}
}
else if ( idCount <= 4 ) {
ownership = new ushort[numLeaves + (4-(numLeaves % 4))];
for ( int i=0; i<numLeaves; ++index ) {
ownership[i++] = idTable[(data[index] >> 0) & 3];
ownership[i++] = idTable[(data[index] >> 2) & 3];
ownership[i++] = idTable[(data[index] >> 4) & 3];
ownership[i++] = idTable[(data[index] >> 6) & 3];
}
}
else if ( idCount <= 16 ) {
ownership = new ushort[numLeaves + (2-(numLeaves % 2))];
for ( int i=0; i<numLeaves; index++ ) {
ownership[i++] = idTable[(data[index] >> 0) & 15];
ownership[i++] = idTable[(data[index] >> 4) & 15];
}
}
else if ( idCount > 16 ) {
ownership = new ushort[numLeaves];
for ( int i=0; i<ownership.Length; ++i, ++index )
ownership[i] = idTable[data[index]];
}
// Read in color table
// Finally, read the leaf data. This part contains the "color" data for each leaf.
for ( int i=0; i<sizeLeaves; ) {
colors[i++] = (byte)(data[index] & 63);
colors[i++] = (byte)((data[index] >> 6 | data[index+1] << 2) & 63);
colors[i++] = (byte)((data[index+1] >> 4 | data[index+2] << 4) & 63);
colors[i++] = (byte)(data[index+2] >> 2);
index += 3;
}
// Fill them into the tree
PopulatorState popstate = new PopulatorState( ref ownership, ref colors );
PopulateTree( root, popstate );
}
private void PopulateTree( Node currentNode, PopulatorState state )
{
if ( currentNode == null ) return;
if ( !currentNode.IsLeaf() ) {
// Walk over the tree in a breath-first manner
PopulateTree( currentNode.BottomRightChild, state );
PopulateTree( currentNode.BottomLeftChild, state );
PopulateTree( currentNode.TopRightChild, state );
PopulateTree( currentNode.TopLeftChild, state );
}
else {
currentNode.Owner = state.CurrentOwner;
currentNode.Color = state.CurrentColor;
state.NextLeaf();
}
}