void DrawLandmark(VNFaceLandmarkRegion2D feature, CGRect scaledBoundingBox, bool closed, UIColor color)
{
if (feature == null)
{
return;
}
var mappedPoints = feature.NormalizedPoints.Select(o => new CGPoint(x: o.X * scaledBoundingBox.Width + scaledBoundingBox.X, y: o.Y * scaledBoundingBox.Height + scaledBoundingBox.Y));
using (var newLayer = new CAShapeLayer())
{
newLayer.Frame = _view.Frame;
newLayer.StrokeColor = color.CGColor;
newLayer.LineWidth = 2;
newLayer.FillColor = UIColor.Clear.CGColor;
using (UIBezierPath path = new UIBezierPath())
{
path.MoveTo(mappedPoints.First());
foreach (var point in mappedPoints.Skip(1))
{
path.AddLineTo(point);
}
if (closed)
{
path.AddLineTo(mappedPoints.First());
}
newLayer.Path = path.CGPath;
}
_shapeLayer.AddSublayer(newLayer);
}
}
// Uses VNUtils to calculate the points, just to test the native API
void ConvertPoints2(VNFaceLandmarkRegion2D landmark, CGRect boundingBox, nuint imgWidth, nuint imgHeight)
{
var points = landmark.Points;
var faceLandmarkPoints = points.Select(p =>
VNUtils.GetImagePoint(p, boundingBox, imgWidth, imgHeight)
);
DispatchQueue.MainQueue.DispatchAsync(() => {
Draw(faceLandmarkPoints.ToArray());
});
}
void ConvertPoints(VNFaceLandmarkRegion2D landmark, CGRect boundingBox)
{
var points = landmark.Points;
var faceLandmarkPoints = points.Select(p => {
return(new CGPoint(
x: ((nfloat)p.X) * boundingBox.Width + boundingBox.X,
y: ((nfloat)p.Y) * boundingBox.Height + boundingBox.Y
));
});
DispatchQueue.MainQueue.DispatchAsync(() => {
Draw(faceLandmarkPoints.ToArray());
});
}