WPF - How can I make a brush that paints graph-paper-like squares?

Answer 1

Use a DrawingBrush. A Drawing can contain shapes, images, text, and media.

The following example uses a DrawingBrush to paint the Fill of a Rectangle.

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a DrawingBrush and use it to
// paint the rectangle.
DrawingBrush myBrush = new DrawingBrush();

GeometryDrawing backgroundSquare =
    new GeometryDrawing(
        Brushes.White,
        null,
        new RectangleGeometry(new Rect(0, 0, 100, 100)));

GeometryGroup aGeometryGroup = new GeometryGroup();
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(0, 0, 50, 50)));
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(50, 50, 50, 50)));

LinearGradientBrush checkerBrush = new LinearGradientBrush();
checkerBrush.GradientStops.Add(new GradientStop(Colors.Black, 0.0));
checkerBrush.GradientStops.Add(new GradientStop(Colors.Gray, 1.0));

GeometryDrawing checkers = new GeometryDrawing(checkerBrush, null, aGeometryGroup);

DrawingGroup checkersDrawingGroup = new DrawingGroup();
checkersDrawingGroup.Children.Add(backgroundSquare);
checkersDrawingGroup.Children.Add(checkers);

myBrush.Drawing = checkersDrawingGroup;
myBrush.Viewport = new Rect(0, 0, 0.25, 0.25);
myBrush.TileMode = TileMode.Tile;

exampleRectangle.Fill = myBrush;

Source: MSDN: WPF Brushes Overview

Answer 2

You can do this in XAML using a VisualBrush. As a sample to give you a starting point, here is a blog post that uses VisualBrush to create a hatched brush. It's very close to a grid - and would be fairly easy to convert across.

Answer 3

from http://msdn.microsoft.com/en-us/library/aa480159.aspx

<DrawingBrush Viewport="0,0,10,10" 
              ViewportUnits="Absolute"
              TileMode="Tile">
  <DrawingBrush.Drawing>
    <DrawingGroup>
      <GeometryDrawing Geometry="M0,0 L1,0 1,0.1, 0,0.1Z" Brush="Green" />
      <GeometryDrawing Geometry="M0,0 L0,1 0.1,1, 0.1,0Z" Brush="Green" />
    </DrawingGroup>
  </DrawingBrush.Drawing>
</DrawingBrush>

Answer 4

I used a 16x16 bitmap with the left and bottom edges black. Then in my window, I set the background to use that, tiled. Here's the XAML (Slightly altered to show up).

<Window.Background>
  <ImageBrush ImageSource="/GraphPaper;component/Background.bmp"
              Stretch="None" TileMode="Tile"
              Viewport="0,0,16,16" ViewportUnits="Absolute" />
</Window.Background>