SkiaSharp is a .NET wrapper for Google’s Skia Graphics Library that can be used to draw 2D graphics across mobile, server, and desktop platforms. SkiaSharp can be used with OpenGL for hardware-accelerated rendering. SkiaSharp was initially developed by Mono but is now maintained by Microsoft and is provided under the MIT License.

💡 This page demonstrates how to create a Surface, draw on it, then convert it to a Bitmap and display it on a PictureBox in a windows forms application. A much better way to achieve this effect in WinForms apps is to simply use the SKGLControl

Code

In this example we are going to use SkiaSharp without the SkiaSharp user control (SKControl). The advantage of the present method is that it can be used in console applications. Other articles on this website demonstrate how to use the control (typically with OpenGL acceleration).

• Edit your build settings to target 32-bit or 64-bit (not any CPU)
• Install the SkiaSharp NuGet package

1. Create a SKSurface and Canvas

var imageInfo = new SKImageInfo(
    width: pictureBox1.Width,
    height: pictureBox1.Height,
    colorType: SKColorType.Rgba8888,
    alphaType: SKAlphaType.Premul);
    
var surface = SKSurface.Create(imageInfo);

var canvas = surface.Canvas;

2. Draw on the Canvas

canvas.Clear(SKColor.Parse("#003366"));

int lineCount = 1000;
for (int i = 0; i < lineCount; i++)
{
    float lineWidth = rand.Next(1, 10);
    var lineColor = new SKColor(
            red: (byte)rand.Next(255),
            green: (byte)rand.Next(255),
            blue: (byte)rand.Next(255),
            alpha: (byte)rand.Next(255));

    var linePaint = new SKPaint
    {
        Color = lineColor,
        StrokeWidth = lineWidth,
        IsAntialias = true,
        Style = SKPaintStyle.Stroke
    };

    int x1 = rand.Next(imageInfo.Width);
    int y1 = rand.Next(imageInfo.Height);
    int x2 = rand.Next(imageInfo.Width);
    int y2 = rand.Next(imageInfo.Height);
    canvas.DrawLine(x1, y1, x2, y2, linePaint);
}

💡 See the full SkiaSharp API to learn more about the available drawing methods

3. Render onto a Bitmap displayed in a Picturebox

Now that we’re done with the drawing, let’s convert this image to a Bitmap so we can display it in a Picturebox. As we’ve discussed previously, as Picturebox is preferred because it is double-buffered and less prone to flickering during animations where the underlying image it displays is frequently updated.

using (SKImage image = surface.Snapshot())
using (SKData data = image.Encode())
using (System.IO.MemoryStream mStream = new System.IO.MemoryStream(data.ToArray()))
{
    pictureBox1.Image?.Dispose();
    pictureBox1.Image = new Bitmap(mStream, false);
}

Source Code

GitHub: SkiaSharpBenchmark