Description VTF Viewer (as name tells) is a tool for viewing Source Engine format texture files. Program allows you to view whole folder full of VTF's and other image files as a collection of thumbnails. You can view all mip levels of VTF files as well as read tVTF Viewer (as name tells) is a tool for viewing Source Engine format texture files. Program allows you to view whole folder full of VTF's and other image files as a collection of thumbnails.