Making a stroke on a figure

Hi everyone

This may be a weird question but is there a way in Unity and C# to make a stroke on or border around a figure/image?

I have some images of squares in my game and at certain times I want them to have a red stroke/border around one of them. You know so people can see that the square has been marked. So I wonder if there’s a function to make this effect happen.

Hope someone can help~

I think you are talking about an outline shader like this :

http://wiki.unity3d.com/index.php/Silhouette-Outlined_Diffuse

Have a look here:

http://forum.unity3d.com/threads/outline-shader.210940/

http://forum.unity3d.com/threads/trying-to-make-a-silhouette-outline-shader.96005/#post-1408098