protected override PixelBox LockImpl( BasicBox lockBox, BufferLocking options )
{
// Check for misuse
if ( ( (int)usage & (int)TextureUsage.RenderTarget ) != 0 )
throw new Exception( "DirectX does not allow locking of or directly writing to RenderTargets. Use BlitFromMemory if you need the contents." );
// Set extents and format
PixelBox rval = new PixelBox( lockBox, Format );
// Set locking flags according to options
D3D.LockFlags flags = D3D.LockFlags.None;
switch ( options )
{
case BufferLocking.Discard:
// D3D only likes D3D.LockFlags.Discard if you created the texture with D3DUSAGE_DYNAMIC
// debug runtime flags this up, could cause problems on some drivers
if ( ( usage & BufferUsage.Dynamic ) != 0 )
flags |= D3D.LockFlags.Discard;
break;
case BufferLocking.ReadOnly:
flags |= D3D.LockFlags.ReadOnly;
break;
default:
break;
}
if ( surface != null )
{
// Surface
DX.DataRectangle data = null;
try
{
if ( lockBox.Left == 0 && lockBox.Top == 0 &&
lockBox.Right == Width && lockBox.Bottom == Height )
{
// Lock whole surface
data = surface.LockRectangle( flags );
}
else
{
System.Drawing.Rectangle prect = ToD3DRectangle( lockBox ); // specify range to lock
data = surface.LockRectangle( prect, flags );
}
}
catch ( Exception e )
{
throw new Exception( "Surface locking failed.", e );
}
FromD3DLock( rval, data );
}
else
{
// Volume
D3D.Box pbox = ToD3DBox( lockBox ); // specify range to lock
DX.DataBox data = volume.LockBox( pbox, flags );
FromD3DLock( rval, data );
}
return rval;
}
