protected void CreateCpuVertexData()
{
if (mVertexDataRecord != null)
{
DestroyCpuVertexData();
// create vertex structure, not using GPU for now (these are CPU structures)
VertexDeclaration dcl = new VertexDeclaration();
VertexBufferBinding bufbind = new VertexBufferBinding();
mVertexDataRecord.CpuVertexData = new VertexData();
mVertexDataRecord.CpuVertexData.vertexBufferBinding = bufbind;
mVertexDataRecord.CpuVertexData.vertexDeclaration = dcl;
// Vertex declaration
// TODO: consider vertex compression
int offset = 0;
// POSITION
// float3(x, y, z)
offset += dcl.AddElement((short)POSITION_BUFFER, offset, VertexElementType.Float3, VertexElementSemantic.Position).Size;
// UV0
// float2(u, v)
// TODO - only include this if needing fixed-function
offset += dcl.AddElement((short)POSITION_BUFFER, offset, VertexElementType.Float2, VertexElementSemantic.TexCoords, 0).Size;
// UV1 delta information
// float2(delta, deltaLODthreshold)
offset = 0;
offset += dcl.AddElement((short)DELTA_BUFFER, offset, VertexElementType.Float2, VertexElementSemantic.TexCoords, 1).Size;
// Calculate number of vertices
// Base geometry size * size
int baseNumVerts = (int)(mVertexDataRecord.Size * mVertexDataRecord.Size);
int numVerts = baseNumVerts;
// Now add space for skirts
// Skirts will be rendered as copies of the edge vertices translated downwards
// Some people use one big fan with only 3 vertices at the bottom,
// but this requires creating them much bigger that necessary, meaning
// more unnecessary overdraw, so we'll use more vertices
// You need 2^levels + 1 rows of full resolution (max 129) vertex copies, plus
// the same number of columns. There are common vertices at intersections
ushort levels = mVertexDataRecord.TreeLevels;
mVertexDataRecord.NumSkirtRowsCols = (ushort)(System.Math.Pow(2, levels) + 1);
mVertexDataRecord.SkirtRowColSkip = (ushort)((mVertexDataRecord.Size - 1) / (mVertexDataRecord.NumSkirtRowsCols - 1));
numVerts += mVertexDataRecord.Size * mVertexDataRecord.NumSkirtRowsCols;
numVerts += mVertexDataRecord.Size * mVertexDataRecord.NumSkirtRowsCols;
HardwareVertexBuffer def = HardwareBufferManager.Instance.CreateVertexBuffer(dcl.Clone(POSITION_BUFFER), numVerts, BufferUsage.StaticWriteOnly, false);//new DefaultHardwareVertexBuffer(dcl.GetVertexSize((short)POSITION_BUFFER), numVerts, BufferUsage.StaticWriteOnly);
//manually create CPU-side buffer
HardwareVertexBuffer posBuf = def;
def = HardwareBufferManager.Instance.CreateVertexBuffer(dcl.Clone(DELTA_BUFFER), numVerts, BufferUsage.StaticWriteOnly, false);//new DefaultHardwareVertexBuffer(dcl.GetVertexSize((short)DELTA_BUFFER),
//numVerts, BufferUsage.StaticWriteOnly);
HardwareVertexBuffer deltabuf = def;
mVertexDataRecord.CpuVertexData.vertexStart = 0;
mVertexDataRecord.CpuVertexData.vertexCount = numVerts;
Rectangle updateRect = new Rectangle(mOffsetX, mOffsetY, mBoundaryX, mBoundaryY);
UpdateVertexBuffer(posBuf, deltabuf, updateRect);
mVertexDataRecord.IsGpuVertexDataDirty = true;
bufbind.SetBinding((short)POSITION_BUFFER, posBuf);
bufbind.SetBinding((short)DELTA_BUFFER, deltabuf);
}
}
/// <summary>
