public ConcurrentDrawingTest()
{
InitializeComponent();
_buttons = TreeHelper.GetLogicalChildren <Button>(this);
// determine grid size defined in XAML
int rows = HostGrid.RowDefinitions.Count;
int columns = HostGrid.ColumnDefinitions.Count;
// create one concurrent DrawingVisual per Grid cell
_visualHosts = new ConcurrentVisualHost[rows * columns];
Func <Visual> createVisual = () => { return(new DrawingVisual()); };
for (int i = 0; i < _visualHosts.Length; i++)
{
ConcurrentVisualHost host = new ConcurrentVisualHost(createVisual);
_visualHosts[i] = host;
HostGrid.Children.Add(host);
Grid.SetColumn(host, i % columns);
Grid.SetRow(host, i / rows);
DrawingVisual visual = (DrawingVisual)host.WorkerVisual;
host.BeginWork(() => DrawName(visual));
}
// concurrent threads require dedicated RNG instances
int ticks = Environment.TickCount;
_twisters = new MersenneTwister[_visualHosts.Length];
for (int i = 0; i < _twisters.Length; i++)
{
_twisters[i] = new MersenneTwister((uint)(ticks + i));
}
}
private void DrawAllContents(bool isConcurrent)
{
// show how long GUI thread is inactive
foreach (Button button in _buttons)
{
button.IsEnabled = false;
}
Dispatcher.DoEvents();
// determine actual size of each grid cell
_cellWidth = (int)HostGrid.ColumnDefinitions[0].ActualWidth;
_cellHeight = (int)HostGrid.RowDefinitions[0].ActualHeight;
for (int i = 0; i < _visualHosts.Length; i++)
{
ConcurrentVisualHost host = _visualHosts[i];
DrawingVisual visual = (DrawingVisual)host.WorkerVisual;
MersenneTwister twister = _twisters[i];
Action action = () => DrawContent(visual, twister);
if (isConcurrent)
{
host.WorkerDispatcher.BeginInvoke(action);
}
else
{
host.WorkerDispatcher.Invoke(action);
}
}
// GUI thread becomes active again
foreach (Button button in _buttons)
{
button.IsEnabled = true;
}
}
