private static void getVertexList(QuantizedMeshStream pStream, ref VertexData[] pVertexList)
{
uint numberOfVertex = pStream.ReadUnsigned32Bit();
pVertexList = new VertexData[numberOfVertex];
for (int index = 0; index < numberOfVertex; index++)
{
pVertexList[index].u = pStream.ReadUnsigned16Bit();
}
for (int index = 0; index < numberOfVertex; index++)
{
pVertexList[index].v = pStream.ReadUnsigned16Bit();
}
for (int index = 0; index < numberOfVertex; index++)
{
pVertexList[index].height = pStream.ReadUnsigned16Bit();
}
// Apply ZigZag (data is compressed)
var u = 0;
var v = 0;
var height = 0;
for (int index = 0; index < numberOfVertex; ++index)
{
u += ZigZagDecode((ushort)pVertexList[index].u);
v += ZigZagDecode((ushort)pVertexList[index].v);
height += ZigZagDecode((ushort)pVertexList[index].height);
pVertexList[index].u = u;
pVertexList[index].v = v;
pVertexList[index].height = height;
}
}
private static void GetIndices(QuantizedMeshStream pStream, ref uint[] pTriangleIndices, SizePerStruct pSizePerStruct)
{
byte bytesInStruct = (pSizePerStruct == SizePerStruct.StructSize_32bit) ? (byte)4 : (byte)2;
var alignment = pStream.GetPosition() % bytesInStruct;
if (alignment != 0)
{
pStream.ReadPadding((byte)(bytesInStruct - alignment));
}
uint triangleCount = pStream.ReadUnsigned32Bit();
pTriangleIndices = new uint[triangleCount * 3]; /* 3 indices for 1 triangle */
for (int index = 0; index < pTriangleIndices.Length; index++)
{
pTriangleIndices[index] = (pSizePerStruct == SizePerStruct.StructSize_32bit) ? pStream.ReadUnsigned32Bit() : pStream.ReadUnsigned16Bit();
}
// Decompress values
uint highest = 0;
for (var i = 0; i < pTriangleIndices.Length; ++i)
{
uint code = pTriangleIndices[i];
pTriangleIndices[i] = highest - code;
if (code == 0)
{
++highest;
}
}
}
private static void getEdgeIndices(QuantizedMeshStream pStream, ref uint[] pEdgeIndices, SizePerStruct pSizePerStruct)
{
uint triangleCount = pStream.ReadUnsigned32Bit();
pEdgeIndices = new uint[triangleCount];
for (int index = 0; index < pEdgeIndices.Length; index++)
{
pEdgeIndices[index] = (pSizePerStruct == SizePerStruct.StructSize_32bit) ? pStream.ReadUnsigned32Bit() : pStream.ReadUnsigned16Bit();
}
}
private void DecodeFile(Stream pInputStream, bool pIsGzipped)
{
if (pInputStream == null)
{
throw new ArgumentNullException("pInputStream");
}
using (var quantizedMeshStream = new QuantizedMeshStream(pInputStream, pIsGzipped))
{
// Read Header
CenterX = quantizedMeshStream.ReadDouble();
CenterY = quantizedMeshStream.ReadDouble();
CenterZ = quantizedMeshStream.ReadDouble();
MinimumHeight = quantizedMeshStream.ReadFloat();
MaximumHeight = quantizedMeshStream.ReadFloat();
BoundingSphereCenterX = quantizedMeshStream.ReadDouble();
BoundingSphereCenterY = quantizedMeshStream.ReadDouble();
BoundingSphereCenterZ = quantizedMeshStream.ReadDouble();
BoundingSphereRadius = quantizedMeshStream.ReadDouble();
HorizonOcclusionPointX = quantizedMeshStream.ReadDouble();
HorizonOcclusionPointY = quantizedMeshStream.ReadDouble();
HorizonOcclusionPointZ = quantizedMeshStream.ReadDouble();
// Read Vertex Data
getVertexList(quantizedMeshStream, ref mVertexList);
// Read Index data (traingle indices)
SizePerStruct structSize = (mVertexList.Length > 65536) ? SizePerStruct.StructSize_32bit : SizePerStruct.StructSize_16bit;
GetIndices(quantizedMeshStream, ref mTriangleIndices, structSize);
// Read edge indices
getEdgeIndices(quantizedMeshStream, ref mWestIndices, structSize);
getEdgeIndices(quantizedMeshStream, ref mSouthIndices, structSize);
getEdgeIndices(quantizedMeshStream, ref mEastIndices, structSize);
getEdgeIndices(quantizedMeshStream, ref mNorthIndices, structSize);
Console.Out.WriteLine(String.Format("{0:0.00000000}", CenterX));
for (int index = 0; index < mVertexList.Length; index++)
{
Console.Out.WriteLine(String.Format("{0:0.00000000} {1:0.00000000} {2:0.00000000}",
Normalize(mVertexList[index].u), Normalize(mVertexList[index].v), GetHeightInMeter(index)));
}
Console.Out.WriteLine(String.Format("{0:0.00000000}", CenterZ));
}
}