d2dlib

To use d2dlib in a Windows Forms application, follow these steps:

1. Inherit your Windows Form or Control from the D2DForm or D2DControl classes provided by d2dwinform.dll.
2. Override the OnRender(D2DGraphics g) method. Do not override the standard .NET OnPaint method.
3. Use the provided D2DGraphics g context inside OnRender to perform your drawing operations.

You can install the d2dlib library using NuGet. For standard installations, use the default package. For 64-bit specific environments, use the x64 package.

Important: Because Direct2D is a platform-associated API, you must set your project's Platform target to either x86 or x64 in the project settings. It will not work with Any CPU if the target is not explicitly defined.

# Standard installation
install-package unvell.d2dlib

# x64 platform installation
install-package unvell.d2dlib-x64

Depending on your target .NET version, you must configure your project architecture to ensure compatibility with the library:

For .NET Core or .NET Framework 4.5 and later

Enable the "Prefer 32-bit" option. This can be found on the 'Build' page of your project settings.

For .NET Framework 4 and earlier

Change your project's build configuration from 'Any CPU' to 'x86' architecture.

To begin using d2dlib for rendering, follow these two steps:

1. Inherit from d2dlib classes: Ensure your Windows Form or Control inherits from either the D2DForm or D2DControl class.
2. Implement drawing logic: Override the OnRender method to perform your drawing operations.

Important: Do not override the OnPaint method; use OnRender instead.

// Example pattern
public class MyD2DForm : D2DForm
{
    protected override void OnRender(Graphics graphics)
    {
        // Your drawing code here
        base.OnRender(graphics);
    }
}

To apply transformations like rotation or scaling to a specific set of drawing operations, use a transform session. This prevents the transformation from affecting subsequent drawing calls outside the session.

1. Call g.PushTransform() to start the session.
2. Apply transformations (e.g., g.RotateTransform(angle, centerPoint)).
3. Perform drawing.
4. Call g.PopTransform() to restore the previous coordinate state.

g.PushTransform();

// rotate 45 degree
g.RotateTransform(45, centerPoint);

g.DrawBitmap(mybmp, rect);

g.PopTransform();

While simple shapes can take a D2DColor, you can use Brush objects for more complex fills and gradients. Brushes are created via the Device object.

• Solid Color Brush: Created via Device.CreateSolidColorBrush(D2DColor color).
• Linear Gradient Brush: Created via Device.CreateLinearGradientBrush(D2DPoint start, D2DPoint end, D2DGradientStop[] stops).
• Radial Gradient Brush: (Supported via the device interface).

// Solid color brush
var brush = Device.CreateSolidColorBrush(new D2DColor(1, 0, 0.5));
g.DrawEllipse(rect, brush);

// Linear gradient brush
var brush = Device.CreateLinearGradientBrush(new D2DPoint(0, 0), new D2DPoint(200, 100),
  new D2DGradientStop[] {
    new D2DGradientStop(0, D2DColor.White),
    new D2DGradientStop(0.5, D2DColor.Green),
    new D2DGradientStop(1, D2DColor.Black),
  });

The D2DGraphics object provides methods similar to the standard Windows Forms graphics interface for drawing primitives and text.

• Rectangles: Use DrawRectangle(D2DRect rect, D2DColor color).
• Ellipses: Use DrawEllipse(D2DEllipse ellipse, D2DColor color).
• Text: Use DrawText(string text, D2DColor color, Font font, float x, float y).

protected override void OnRender(D2DGraphics g)
{
  // Draw a rectangle
  var rect = new D2DRect(0, 0, 10, 10);
  g.DrawRectangle(rect, D2DColor.Red);

  // Draw an ellipse
  var ellipse = new D2DEllipse(0, 0, 10, 10);
  g.DrawEllipse(ellipse, D2DColor.Gray);

  // Draw text
  g.DrawText("Hello World", D2DColor.Yellow, this.Font, 100, 200);
}