public void TestSurroudingAnchor(bool virtualizeItems)
{
var stackSize = new Vector3(100, 200, 300);
var childSize1 = new Vector3(50, 150, 250);
var childSize2 = new Vector3(150, 250, 350);
var childSize3 = new Vector3(250, 250, 350);
var stackPanel = new StackPanel { Size = stackSize, ItemVirtualizationEnabled = virtualizeItems, Orientation = Orientation.Horizontal };
var child1 = new StackPanel { Size = childSize1 };
var child2 = new StackPanel { Size = childSize2 };
var child3 = new StackPanel { Size = childSize3 };
stackPanel.Children.Add(child1);
stackPanel.Children.Add(child2);
stackPanel.Children.Add(child3);
stackPanel.Arrange(Vector3.Zero, false);
// checks in the scrolling direction
stackPanel.ScrollToBeginning(Orientation.Horizontal);
Utilities.AssertAreNearlyEqual(new Vector2(0, 50), stackPanel.GetSurroudingAnchorDistances(Orientation.Horizontal, 0));
stackPanel.ScrolllToElement(0.5f);
Utilities.AssertAreNearlyEqual(new Vector2(-25, 25), stackPanel.GetSurroudingAnchorDistances(Orientation.Horizontal, 0));
stackPanel.ScrolllToElement(1f);
Utilities.AssertAreNearlyEqual(new Vector2(0, 150), stackPanel.GetSurroudingAnchorDistances(Orientation.Horizontal, 0));
stackPanel.ScrolllToElement(2 + 3/5f);
Utilities.AssertAreNearlyEqual(new Vector2(-150, 100), stackPanel.GetSurroudingAnchorDistances(Orientation.Horizontal, 0));
stackPanel.ScrollToEnd(Orientation.Horizontal);
Utilities.AssertAreNearlyEqual(new Vector2(-150, 100), stackPanel.GetSurroudingAnchorDistances(Orientation.Horizontal, 0));
// checks in other directions
Assert.AreEqual(new Vector2(0, 200), stackPanel.GetSurroudingAnchorDistances(Orientation.Vertical, -1));
Assert.AreEqual(new Vector2(-100, 100), stackPanel.GetSurroudingAnchorDistances(Orientation.Vertical, 100));
Assert.AreEqual(new Vector2(-200, 0), stackPanel.GetSurroudingAnchorDistances(Orientation.Vertical, 500));
Assert.AreEqual(new Vector2(0, 300), stackPanel.GetSurroudingAnchorDistances(Orientation.InDepth, -1));
Assert.AreEqual(new Vector2(-150, 150), stackPanel.GetSurroudingAnchorDistances(Orientation.InDepth, 150));
Assert.AreEqual(new Vector2(-300, 0), stackPanel.GetSurroudingAnchorDistances(Orientation.InDepth, 500));
}