Polygon scaling

10-13-2009 12:06 PM |

 Now I'm trying to implement a map which is using vector data and I ran into a strange effect while scaling polygons. When polygons become very large their strokes start being distorted in various ways. I made a little example but it couldn't get the same strange effect. Anyway you'll be able to see another strange effect if you press the button about 20 times. I would like to know how to avoid this effect or to at least to know why it happens?

Here is the example:

XAML:

<Grid x:Name="LayoutRoot">
    <Polygon x:Name="polygon" Points="0,0,1,0,1,1" Stroke="Red" Fill="Blue" StrokeThickness="1" />
    <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
        <TextBlock x:Name="tbPoints" Foreground="Black" />
        <Button x:Name="btnScale" Click="btnScale_Click" Content="0"  />
    </StackPanel>
</Grid>

C#:

public partial class MainPage : UserControl
{
	static int _counter = 0;

	public MainPage()
	{
		InitializeComponent();
		
	}

	private void btnScale_Click(object sender, RoutedEventArgs e)
	{
		string pos = "";
		for (int i = 0; i < polygon.Points.Count; i++)
		{
			polygon.Points = new Point(polygon.Points.X * 2, polygon.Points.Y * 2);
			pos += "(" + polygon.Points.X + ", " + polygon.Points.Y + ")";
		}

		tbPoints.Text = pos;
		btnScale.Content = (++_counter).ToString();
	}
}

Re: Polygon scaling

10-13-2009 12:18 PM |

 I see the forum parser makes strange effect too: