public PageTable( D3D10.Device device, PageCache cache, VirtualTextureInfo info, PageIndexer indexer )
{
this.info = info;
this.device = device;
this.indexer = indexer;
quadtree = new Quadtree(new Rectangle(0, 0, info.PageTableSize, info.PageTableSize), MathExtensions.Log2(info.PageTableSize));
int size = info.PageTableSize;
texture = new Direct3D.Texture( device, size, size, DXGI.Format.R8G8B8A8_UNorm, D3D10.ResourceUsage.Default, 0 );
staging = new Direct3D.WriteTexture( device, size, size, DXGI.Format.R8G8B8A8_UNorm );
cache.Added += ( Page page, Point pt ) => quadtree.Add( page, pt );
cache.Removed += ( Page page, Point pt ) => quadtree.Remove( page );
SetupDataAndInfo();
}
// Static Functions
static Rectangle GetRectangle( Quadtree node, int index )
{
int x = node.Rectangle.X;
int y = node.Rectangle.Y;
int w = node.Rectangle.Width/2;
int h = node.Rectangle.Height/2;
switch( index )
{
case 0: return new Rectangle( x, y, w, h );
case 1: return new Rectangle( x + w, y, w, h );
case 2: return new Rectangle( x + w, y + h, w, h );
case 3: return new Rectangle( x, y + h, w, h );
}
throw new ArgumentOutOfRangeException( "index" );
}
static void Write( Quadtree node, SimpleImage image, int miplevel )
{
if( node.Level >= miplevel )
{
int rx = node.Rectangle.X >> miplevel;
int ry = node.Rectangle.Y >> miplevel;
int rw = node.Rectangle.Width >> miplevel;
int rh = node.Rectangle.Height >> miplevel;
SimpleImage.Fill( image, new Rectangle( rx, ry, rw, rh ), (byte)node.Mapping.X, (byte)node.Mapping.Y, (byte)node.Level, 255 );
foreach( Quadtree child in node.Children )
if( child != null )
Quadtree.Write( child, image, miplevel );
}
}
static Quadtree FindPage( Quadtree node, Page request, out int index )
{
int scale = 1 << request.Mip; // Same as pow( 2, mip )
int x = request.X * scale;
int y = request.Y * scale;
// Find the parent of the child we want to remove
bool exitloop = false;
while( !exitloop )
{
exitloop = true;
for( int i = 0; i < 4; ++i )
{
if( node.Children[i] != null && node.Children[i].Rectangle.Contains( x, y ) )
{
// We found it
if( request.Mip == node.Level-1 )
{
index = i;
return node;
}
// Check the children
else
{
node = node.Children[i];
exitloop = false;
}
}
}
}
// We couldn't find it so it must not exist anymore
index = -1;
return null;
}