Efficient way to draw a single point on canvas

Question

I am looking for a way to draw a single point (with a color) on C# canvas. In android I would do something like

paint.Color = Color.Rgb (10, 10, 10);
canvas.DrawPoint (x, y, paint);

So I thought that I would be able to find it in the Shape class, but it was not there. Am I missing something or there is no way to draw a single point?

In the second case, what is a recommended way of drawing a point? In HTML5 canvas there is a similar problem and people are drawing points using rectangles/circles.

P.S. a question with similar title Add Point to Canvas is not answering it and moving into "how to draw a shape".

What UI library are you using? Winforms? WPF? Metro? Something else? — svick, Nov 08 '13 at 02:04
http://msdn.microsoft.com/en-us/library/system.windows.point(v=vs.110).aspx — Millie Smith, Nov 08 '13 at 02:13
point as in what? you shall go for drawing an ellipse there. — A.K., Nov 08 '13 at 09:59
I would guess a Line would be the most lightweight Shape. If you want, you could derive as Dot class from Shape, but when you define a geometry, you must use one of the existing geometries such as LineGeometry. I wrote a rudimentary Dot shape just for fun and it works more or less, but I don't believe it's really useful... — Thejaka Maldeniya, Feb 08 '14 at 15:09

Romano · Answer 1 · 2016-04-07T17:17:07.790

5

I just ran in the same question for UWP, I finally decided to use an Ellipse:

int dotSize = 10;

Ellipse currentDot = new Ellipse();
currentDot.Stroke = new SolidColorBrush(Colors.Green);
currentDot.StrokeThickness = 3;
Canvas.SetZIndex(currentDot, 3);
currentDot.Height = dotSize;
currentDot.Width = dotSize;
currentDot.Fill = new SolidColorBrush(Colors.Green);
currentDot.Margin = new Thickness(100, 200, 0, 0); // Sets the position.
myGrid.Children.Add(currentDot);

edited Apr 07 '16 at 17:17

answered Apr 07 '16 at 16:52

Romano

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Hi what is `myGrid`? Did you mean YourCanvas? – Khalil Khalaf Jul 11 '16 at 19:59
Hi FirstStep, it is actually a Grid object inside a Canvas in the XAML: ` ` But you probably can draw in the canvas directly, don't have time to test but I'll be surprised if it was not possible. – Romano Jul 13 '16 at 19:37
I see no I get what you mean, just wanted to make sure so thanks – Khalil Khalaf Jul 13 '16 at 19:41

score 1 · Answer 2 · answered Feb 14 '14 at 14:03

What about a Polyline?

xaml:

<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
    <Canvas x:Name="canvas" Background="#00FFFFFF" MouseMove="Canvas_MouseMove">
        <Polyline x:Name="polyline" Stroke="DarkGreen" StrokeThickness="3"/>
    </Canvas>
</Grid>

c#:

private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
{
    polyline.Points.Add(new Point(0,0));
    polyline.Points.Add(new Point(0, 1));
    polyline.Points.Add(new Point(1, 0));
    polyline.Points.Add(new Point(1, 1));
}

Efficient way to draw a single point on canvas

2 Answers2