So as an Architectural designer we are often trying to show clients, and jurisdictions what will actually get built with our renderings. Glass is a tricky thing to get right, and when you throw in coatings and colors it gets even more difficult to tune it properly. I think I've come up with a way to tweak Revit materials to show these glasses properly, and have a system for matching any glass/ coating providers products. It helps to have a glass provider that has a good website that has all the date we need to specify glass (Vitro glass is an industry standard and has great resources for this) . The diffuse color is the tint of the glass as presented by the manufacturer, the reflectivity is set by the Exterior reflectance number and the tint sets the Visual Light Transmission as a percentage of 255 (solid black). See image for a visual explanation.