You need Visual Studio from Microsoft from Visual Studio 2015 website.
The shaders used by Microsoft Visual Studio 2015 come like DGSL file.
This extension is associated with the Microsoft Visual Studio integrated development environment that allows programmers to create applications for Microsoft Windows, Windows Phone, web, etc.
Also, the .dgsl file stores definitions of 3D surfaces.
Any of the dgsl file types can be found here: C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\Microsoft\VsGraphics\Assets\Effects\;
You can see one screenshot of the visual one shaders.