protected override Paint GetPaintInner(Windows.Foundation.Rect destinationRect)
{
var paint = new Paint();
// Android LinearGradient requires two ore more stop points.
if (GradientStops.Count >= 2)
{
var colors = GradientStops.Select(s => ((Android.Graphics.Color)s.Color).ToArgb()).ToArray();
var locations = GradientStops.Select(s => (float)s.Offset).ToArray();
var width = destinationRect.Width;
var height = destinationRect.Height;
var transform = RelativeTransform?.ToNativeTransform(size: new Windows.Foundation.Size(width, height), isBrush: true);
//Matrix .MapPoints takes an array of floats
var pts = new[] { StartPoint, EndPoint }
.Select(p => new float[] { (float)(p.X * width), (float)(p.Y * height) })
.SelectMany(p => p)
.ToArray();
transform?.MapPoints(pts);
var shader = new LinearGradient(pts[0], pts[1], pts[2], pts[3], colors, locations, Shader.TileMode.Mirror);
paint.SetShader(shader);
}
return(paint);
}
internal CAGradientLayer GetLayer(CGSize size)
{
var gradientLayer = new CAGradientLayer();
gradientLayer.Colors = GradientStops.Select(gs => (CGColor)gs.Color).ToArray();
gradientLayer.Locations = GradientStops.Select(gs => new NSNumber(gs.Offset)).ToArray();
var transform = RelativeTransform?.ToNativeTransform(size);
gradientLayer.StartPoint = transform?.TransformPoint(StartPoint) ?? StartPoint;
gradientLayer.EndPoint = transform?.TransformPoint(EndPoint) ?? EndPoint;
return(gradientLayer);
}
/// <summary>
/// Create matrix to transform image based on relative dimensions of bitmap and drawRect, Stretch mode, and RelativeTransform
/// </summary>
/// <param name="drawRect"></param>
/// <param name="bitmap"></param>
/// <returns></returns>
private Android.Graphics.Matrix GenerateMatrix(Foundation.Rect drawRect, Bitmap bitmap)
{
var matrix = new Android.Graphics.Matrix();
// Note that bitmap.Width and bitmap.Height (in physical pixels) are automatically scaled up when loaded from local resources, but aren't when acquired externally.
// This means that bitmaps acquired externally might not render the same way on devices with different densities when using Stretch.None.
var sourceRect = new Foundation.Rect(0, 0, bitmap.Width, bitmap.Height);
var destinationRect = GetArrangedImageRect(sourceRect.Size, drawRect);
matrix.SetRectToRect(sourceRect.ToRectF(), destinationRect.ToRectF(), Android.Graphics.Matrix.ScaleToFit.Fill);
RelativeTransform?.ToNativeTransform(matrix, new Size(drawRect.Width, drawRect.Height), isBrush: true);
return(matrix);
}
internal CAGradientLayer GetLayer(CGSize size)
{
var gradientLayer = new CAGradientLayer();
gradientLayer.Colors = GradientStops.Select(gs => (CGColor)gs.Color).ToArray();
gradientLayer.Locations = GradientStops.Select(gs => new NSNumber(gs.Offset)).ToArray();
var transform = RelativeTransform?.ToNativeTransform(size);
#if __IOS__
gradientLayer.StartPoint = transform?.TransformPoint(StartPoint) ?? StartPoint;
gradientLayer.EndPoint = transform?.TransformPoint(EndPoint) ?? EndPoint;
return(gradientLayer);
#elif __MACOS__
throw new NotImplementedException();
#endif
}
