Question

I’m writing a program in WPF application that simulates the game of life.
How can I preform GDI+ like graphics operations to create an Image that contains the grid of cells?

(Normally, in WinForms, I would have know how to do this operation).

Edit:
I used this code:

            WriteableBitmap wb = new WriteableBitmap(width * 5, height * 5, 100, 100, new PixelFormat(), new BitmapPalette(new List<Color> { Color.FromArgb(255, 255, 0, 0) }));
        wb.WritePixels(new Int32Rect(0, 0, 5, 5), new IntPtr(), 3, 3);
        Background.Source = wb;

Background is a System.Windows.Controls.Image Control

Answer 1

I think you’re making things harder on yourself by using WriteableBitmap.WritePixel. You’ll have a much better time drawing with Shapes or using RendterTargetBitmap and a DeviceContext.

Here’s some code on how you would draw using this method.

MainForm’s XAML:

<Grid>
    <Image Name="Background"
           Width="200"
           Height="200"
           VerticalAlignment="Center"
           HorizontalAlignment="Center" />
</Grid>

MainForm’s Code-Behind:

private RenderTargetBitmap buffer;
private DrawingVisual drawingVisual = new DrawingVisual();

public MainWindow()
{
    InitializeComponent();            
}

protected override void OnRender(DrawingContext drawingContext)
{
    base.OnRender(drawingContext);
    buffer = new RenderTargetBitmap((int)Background.Width, (int)Background.Height, 96, 96, PixelFormats.Pbgra32);
    Background.Source = buffer;
    DrawStuff();
}

private void DrawStuff()
{
    if (buffer == null)
        return;

    using (DrawingContext drawingContext = drawingVisual.RenderOpen())
    {
        drawingContext.DrawRectangle(new SolidColorBrush(Colors.Red), null, new Rect(0, 0, 10, 10));
    }

    buffer.Render(drawingVisual);
}

Adjust the Width/Height of the Image to whatever you desire. All of your drawing logic should be inside of the using statement. You’ll find the methods on DrawingContext are much more flexible and easier to understand than WritePixel. Call “DrawStuff” whenever you want to trigger a redraw.