private Line CreateAnchor(UIElement element, double x, double y)
{
var anchor = new Line()
{
X1 = 0,
Y1 = 0,
X2 = 80,
Y2 = 0
};
SetAnchorProperties(anchor);
var anchorVisual = ElementCompositionPreview.GetElementVisual(anchor);
var elementVisual = ElementCompositionPreview.GetElementVisual(element);
var centerVisual = ElementCompositionPreview.GetElementVisual(_centerContent);
var elementNode = elementVisual.GetReference();
var centerNode = centerVisual.GetReference();
ScalarNode expression;
var elementY = elementNode.Offset.Y + (elementNode.Size.Y / 2);
var centerY = centerNode.Offset.Y + (centerNode.Size.Y / 2);
var elementX = elementNode.Offset.X + (elementNode.Size.X / 2);
var centerX = centerNode.Offset.X + (centerNode.Size.X / 2);
var startingAngle = Math.Atan2(y, x);
if (startingAngle > Math.PI / 4 && startingAngle < 3 * Math.PI / 4)
{
expression = ExpressionFunctions.ATan((-1 * (elementX - centerX)) / (elementY - centerY)) - ((float)Math.PI / 2.0f);
}
else if (startingAngle >= 3 * Math.PI / 4 || startingAngle < -3 * Math.PI / 4)
{
expression = ExpressionFunctions.ATan((elementY - centerY) / (elementX - centerX)) + (float)Math.PI;
}
else if (startingAngle >= -3 * Math.PI / 4 && startingAngle < Math.PI / -4)
{
expression = ExpressionFunctions.ATan((elementX - centerX) / (-1 * (elementY - centerY))) + ((float)Math.PI / 2.0f);
}
else
{
expression = ExpressionFunctions.ATan((elementY - centerY) / (elementX - centerX));
}
anchorVisual.CenterPoint = new Vector3(0);
anchorVisual.StartAnimation(nameof(anchorVisual.RotationAngle), expression);
var offsetExpression = ExpressionFunctions.Vector3(centerNode.Offset.X + (centerNode.Size.X / 2), centerNode.Offset.Y + (centerNode.Size.Y / 2), 0);
anchorVisual.StartAnimation(nameof(anchorVisual.Offset), offsetExpression);
var scaleExpression = ExpressionFunctions.Vector3(ExpressionFunctions.Pow(ExpressionFunctions.Pow(elementX - centerX, 2) + ExpressionFunctions.Pow(elementY - centerY, 2), 0.5f) / 80, 1, 1);
anchorVisual.StartAnimation(nameof(anchorVisual.Scale), scaleExpression);
return(anchor);
}
