/// <summary>
/// Helper used by BeginDraw. This checks the graphics device status,
/// making sure it is big enough for drawing the current control, and
/// that the device is not lost. Returns an error string if the device
/// could not be reset.
/// </summary>
string HandleDeviceReset()
{
bool deviceNeedsReset = false;
switch (GraphicsDevice.GraphicsDeviceStatus)
{
case GraphicsDeviceStatus.Lost:
// If the graphics device is lost, we cannot use it at all.
return("Graphics device lost");
case GraphicsDeviceStatus.NotReset:
// If device is in the not-reset state, we should try to reset it.
deviceNeedsReset = true;
break;
default:
// If the device state is ok, check whether it is big enough.
PresentationParameters pp = GraphicsDevice.PresentationParameters;
deviceNeedsReset = (ClientSize.Width > pp.BackBufferWidth) ||
(ClientSize.Height > pp.BackBufferHeight);
break;
}
// Do we need to reset the device?
if (deviceNeedsReset)
{
try
{
graphicsDeviceService.ResetDevice(ClientSize.Width,
ClientSize.Height);
}
catch (Exception e)
{
return("Graphics device reset failed\n\n" + e);
}
}
return(null);
}
