void Canvas_Draw()

in ExampleGallery/CustomEffects.xaml.cs [135:206]

• 45 lines of code
• 8 McCabe index (conditional complexity)

        void Canvas_Draw(ICanvasAnimatedControl sender, CanvasAnimatedDrawEventArgs args)
        {
            var elapsedTime = (float)args.Timing.TotalTime.TotalSeconds;

            // Center in the control.
            var position = (sender.Size.ToVector2() - tigerSize) / 2;
            position.Y -= tigerSize.Y * 0.75f;

            // Is the sketch effect enabled?
            ICanvasImage sourceImage;

            if (SketchEnabled)
                sourceImage = sketchEffect;
            else
                sourceImage = bitmapTiger;

            // Which dissolve mode are we currently displaying?
            ICanvasImage dissolveMask;

            switch (CurrentDissolve)
            {
                case DissolveType.Ripples:
                    // Use the custom rippleEffect as our dissolve mask, and animate its offset.
                    dissolveMask = rippleEffect;
                    rippleEffect.Properties["offset"] = -elapsedTime * 6;
                    break;

                case DissolveType.Turbulence:
                    // Use a turbulence image as the dissolve mask.
                    dissolveMask = turbulence;
                    break;

                case DissolveType.LinearGradient:
                    // Use a linear gradient as the dissolve mask, and slowly rotate it.
                    dissolveMask = linearGradient;
                    linearGradient.TransformMatrix = Matrix3x2.CreateRotation(elapsedTime / 3, tigerSize / 2);
                    break;

                case DissolveType.RadialGradient:
                    // Use a radial gradient as the dissolve mask.
                    dissolveMask = radialGradient;
                    break;

                case DissolveType.NoDissolve:
                    // Dissolve is turned off, so just draw the source image directly.
                    args.DrawingSession.DrawImage(sourceImage, position);
                    return;

                default:
                    throw new NotSupportedException();
            }

            // Animate the dissolve amount.
            dissolveEffect.Properties["dissolveAmount"] = (float)Math.Sin(elapsedTime * 2.4) / 2 + 0.5f;

            // Draw the custom effect.
            dissolveEffect.Source1 = sourceImage;
            dissolveEffect.Source2 = dissolveMask;

            args.DrawingSession.DrawImage(dissolveEffect, position);

            if (!ThumbnailGenerator.IsDrawingThumbnail)
            {
                // Display the current dissolve mask.
                args.DrawingSession.DrawText("Dissolve mask:", position.X, position.Y + tigerSize.Y * 1.5f - 32, Colors.Gray);
                args.DrawingSession.DrawImage(dissolveMask, position.X, position.Y + tigerSize.Y * 1.5f, bitmapTiger.Bounds);

                // Display the current dissolve amount.
                string dissolvePercentage = string.Format("{0:0}%", (float)dissolveEffect.Properties["dissolveAmount"] * 100);
                args.DrawingSession.DrawText(dissolvePercentage, position + tigerSize * new Vector2(1.2f, 0.4f), Colors.Gray);
            }
        }