How to do c# collision detection?

user1866990 picture user1866990 · Apr 21, 2013 · Viewed 18.3k times · Source

Are there any predefined methods in c# which allow for collision detection?

I am new to c# and am trying to get collision detection of two ellipses are there any predefined ways collision detection can be implemented?

I already have code which draws the ellipses, what would be a good way to start the collision detection?

private void timer1_Tick(object sender, EventArgs e)
    {
        //Remove the previous ellipse from the paint canvas.
        canvas1.Children.Remove(ellipse);

        if (--loopCounter == 0)
            timer.Stop();

        //Add the ellipse to the canvas
        ellipse = CreateAnEllipse(20, 20);
        canvas1.Children.Add(ellipse);

        Canvas.SetLeft(ellipse, rand.Next(0, 500));
        Canvas.SetTop(ellipse, rand.Next(0, 310));
    }

    // Customize your ellipse in this method
    public Ellipse CreateAnEllipse(int height, int width)
    {
        SolidColorBrush fillBrush = new SolidColorBrush() { Color = Colors.Yellow};
        SolidColorBrush borderBrush = new SolidColorBrush() { Color = Colors.Black };

        return new Ellipse()
        {
            Height = height,
            Width = width,
            StrokeThickness = 1,
            Stroke = borderBrush,
            Fill = fillBrush
        }; 
    }

this is the code to draw an ellipse which then gets removed and appears in another position.

Answer

David picture David · Apr 21, 2013

I have tested this, it worked, at least for me

enter image description here

var x1 = Canvas.GetLeft(e1);
var y1 = Canvas.GetTop(e1);
Rect r1 = new Rect(x1, y1, e1.ActualWidth, e1.ActualHeight);


var x2 = Canvas.GetLeft(e2);
var y2 = Canvas.GetTop(e2);
Rect r2 = new Rect(x2, y2, e2.ActualWidth, e2.ActualHeight);

if (r1.IntersectsWith(r2))
    MessageBox.Show("Intersected!");
else
    MessageBox.Show("Non-Intersected!");