Glass rendering tips for realistic visualizations

Summary: 

• Dan Stine shares how to create realistic architectural glazing in Enscape directly from Revit and SketchUp.
• Understand how Enscape interprets different material types and how to fine-tune key properties like transparency, reflectivity, and roughness.
• Discover the impact of ray-traced sun shadows for more natural lighting through semi-transparent and tinted glass.
• Learn how the Material Library can help with faster workflows and consistent results across teams.

Author's note:

I regularly teach daylight design to graduate architecture students and present to professional audiences on daylighting and lighting analysis, including recurring lectures for the University of Minnesota’s Lighting Design program. Those talks emphasize how glazing supports daylight, view, wayfinding, and circadian considerations—and how to translate that intent into settings that look right and behave plausibly in real time.

This post shows how to produce convincing architectural glazing in Enscape straight from Revit and SketchUp. It explains how Enscape interprets common Revit/SketchUp material types (e.g., Generic, Glazing, advanced/PBR) and how to tune transparency, reflectivity, and roughness in the Enscape Material Editor.

It also highlights important improvements, such as ray-traced sun shadows that allow semitransparent and tinted glass to cast colored light on interior surfaces, and the Material Library and “Replace with Enscape Material” workflow for faster, more consistent results across teams.

Table of contents

1. Realistic glass rendering in architectural visualization 
2. Defining glass in Revit 
3. Glass rendering in SketchUp
4. How to render glass in Revit 
5. Visible light reflectance (VLR) 
6. Glazing material 
7. Glass support in Enscape Material Editor 
8. Colored transmissive light
9. Conclusion

Architectural glazing

Glass—“architectural glazing” in our curtain walls and windows—does more than separate inside from out. It provides daylight and desirable warmth in colder seasons, supports a visual connection to nature during busy workdays, helps people orient themselves in large buildings, and contributes to circadian health and well-being when the spectrum, timing, and intensity are considered in design. In the renderings we share with clients, glazing should therefore look convincing (clarity, reflection, tint) and behave credibly (transmit and reflect light in a way that matches the design intent). Enscape’s livelink workflow makes that possible directly inside Revit and SketchUp without exporting, which is why glazing has become one of the most satisfying materials to “get right.”

Realistic glass rendering in architectural visualization

For years, glass was hard to depict well: reflections could look wrong, colors felt off, or the steps required were too technical for typical design schedules. Today, Enscape’s Material Editor (available in supported CAD platforms, like Revit and SketchUp) gives direct access to physically-based controls such as tint, transparency, roughness, and a dedicated Glass type, while the Material lLibrary supplies ready-made PBR assets you can use as-is or customize. These tools live inside your CAD host application, so you adjust a parameter and see the result immediately.

When ray-traced sun shadows are enabled, semi-transparent geometry—including tinted and patterned glass—casts shadows whose opacity and tint reflect the material, so a band of colored glazing now paints color onto floors and walls in sunlight. This makes façade color decisions intelligible in real-time.

Defining glass in Revit

This article focuses on glazing in Revit because the underlying material system offers multiple paths: Generic, Glazing, and the newer Advanced (PBR) appearance assets introduced in Revit 2019. Understanding how these map into Enscape’s physically based model is the key to achieving predictable results.

Without leaving the Revit environment, Enscape also provides its own Material Editor (see image below); using it, you can:

• Set Type = Glass
• Apply a Base Texture for stained glass
• Add Bump/Normal
• Adjust Opacity
• Enable Frosted to blur based on roughness

Glass rendering in SketchUp

SketchUp’s best glazing workflows run through the Enscape Material Editor. Because SketchUp’s native material system is limited, the Enscape editor supplies the missing PBR controls and the same Glass type you see in Revit – in fact, you can share Enscape-defined materials between Revit and SketchUp. The two most influential settings for typical architectural glass are Tint Color (for VLT hue) and Reflection Roughness (for reflectivity sharpness). You can also drive patterns through Transparency cutouts (frits or lamination graphics) and load a Base Texture with a bump/normal for stained glass or textured glass effects.

Image (from SketchUp): three panes with different settings.

1. Tint Color for typical VLT
2. Transparency Texture (Type = Transmittance) for frit/pattern
3. Albedo/Opacity for frosted/etched looks.

The image below shows the Enscape material editor settings for the frosted glass (#3). Notice the Type is set to Generic. Similar results can be achieved using the Glass type and checking Frosted.

In addition, the Refractive Index control bends light for thick glass scenarios; air is 1.0, water is 1.33, and typical window glass is about 1.52. Architectural glazing often uses very little distortion (near 1.0) for clarity and efficiency.

How to render glass in Revit

Revit offers three common approaches that all render well in Enscape when set up correctly: Generic, Glazing, and Advanced. You can stay entirely within Revit’s native editor or use the Enscape Material Editor to drive a Revit material as Glass. Either way, in Enscape’s General Settings dialog, set Material Selection to Appearance (not Graphics) so the renderer reads Appearance assets rather than shaded overrides; this one setting resolves many “why does it look wrong?” questions.

Default glass material

Many Revit templates ship with a “Glass” material using the Glazing shader but with a very low Reflectance, which can make curtain walls look like they have no glass at all. Raising reflectance creates believable exterior reflections in Enscape; as shown in the comparisons below; from 0 to 50 to 100 illustrates the impact clearly.

Advanced material

Revit’s Advanced appearance assets (PBR) include a physicallybased Glazing shader and a separate Transparent (for regular Glass) shader. The glazing asset exposes real-world inputs such as Visible Transmittance (VLT) and a transmissive color. Those parameters are helpful for daylight and energy modeling workflows, and Enscape accurately renders the transmissive color.

Designers who specify glazing or are involved in daylight analysis will be familiar with these real-world physical properties. Revit, Autodesk Lighting Analysis, ElumTools, and Autodesk Insight also use this information for daylight and energy analysis. In the chart below (from the Autodesk Insight help documentation), we see the VLT range is from about 60 – 90%.

The transmissive color corresponds to the inherent color in the raw materials used to create the glass. The light assumes this color as it passes through the glass. Using Revit’s advanced material shader for glazing, when the correct color is entered, from a manufacturer’s data sheet, for example, the Visible Transmittance (VLT) value is correctly calculated as well, as shown in the image below. VLT is the total amount of light that passes through the glass. FYI: Vitro example used can be found here.

The following image shows the results of this material definition within Enscape. It is easy to see the transmissive color within the glass, which is great!

 Tip: Adjust the Luminance value within Revit's color dialog to adjust the VLT when using a color rather than grayscale RGB. This ElumTools article describes how to map an RGB value to a real-world VLT value.

Here is another example using a much lower VLT value from the manufacturer’s product line.

Generic material

If you prefer direct control, Revit’s Generic shader is flexible and reliable in Enscape. From a manufacturer's datasheet, you can sample the RGB tint and approximate VLT by mapping the percentage to Revit’s 0–255 grayscale (255 × VLT ≈ RGB value for greyscale), or by using the color chip and adjusting Luminance to tune transmission. Add Transparency (Transmittance) for frit or patterns, and dial Specular and Roughness to balance mirror-like reflections with a softer, satin read. This method is still one of the fastest paths to matching a product line.

The image below highlights the various settings for each shader type in Revit. Notice that Generic has the most options.

In the manufacturer's datasheet shown below, the glass color and reflectance can be mapped directly (tip: use an eyedropper tool in a graphics app to get the RGB value of the color). The VLT can be translated as a percentage of Revit’s 255 shades of gray; thus, 255 x VLT = RGB value (enter the result for all three). This is achieved using the Tint parameter.

Visible light reflectance (VLR)

Revit’s reflectivity sliders don’t map 1:1 to manufacturer VLR values; Enscape normalizes those sliders to physically plausible glass reflectance so that a “medium” setting renders like roughly 4% F0 reflectance, with the upper end near 12%. That normalization helps keep your glass believable while you focus on artistic intent.

Glazing material

Back to Revit’s Glazing material: following the same steps used for the Generic shader (match the tint to the datasheet and adjust reflectance/roughness) yields similar results in Enscape—and the tint still drives the perceived VLT. If your project or analysis workflow requires the Advanced/PBR Glazing asset because of its explicit VLT control, you can use it and still achieve great looks in Enscape.

Glass material in Enscape

Enscape’s Material Library and Material Editor have matured substantially in recent years. You can import pre-built PBRs, store materials in a shared location, batchimport or export .matpkg files, and even Replace with Enscape Material to swap a Revit/SketchUp material for an Enscape library version in one step. These features make it easy to publish a small set of vetted glazing materials for office-wide use and maintain consistency across projects.

For the material itself, the Enscape Glass type gives direct control over Tint Color, Opacity, Reflection Roughness, and Frosted blurring. You can assign a Base Texture for stained or patterned glass and add Bump/Normal for subtle relief—ideal for decorative laminates or art glass. In scenes with sunlight, turning on RayTraced Sun Shadows allows that tint to affect the sun patches indoors; with artificial lights, enabling RayTraced Artificial Light at High quality or above reveals semi-transparent effects as well.

Here are the Enscape-provided “glass” materials. None of these glass options is set to the material type “Glass”, so they are defined generically.

Related reading: If you explore Revit’s Advanced base assets as templates for glazing families, this short primer on the five “base materials” is helpful background: Revit Advanced Materials - Base Material Templates.

Colored light update

I wrote a blog post in 2017 highlighting a presentation I gave to my graduate architecture students on custom curtainwalls in Revit with colored glazing. Notice how Enscape now supports the colored transmissive light on the interior wall, compared to the original image below.

Conclusion

There’s always more to say about glazing—from view quality, to solar control, to the psychology of interior color—but the steps above are enough to achieve the results shown here and to convey design intent clearly to clients and stakeholders. In practice, the fastest way to reliable, beautiful output is to use the Enscape Material Editor’s Glass type (or a well-tuned Revit Generic or Glazing shader), match tint/opacity/roughness to the datasheet, and enable RayTraced Sun Shadows for sunlight and Ray-Traced Artificial Light for electric light when you need semi-transparent effects to read. Keep Enscape open while you tweak; the real-time feedback shortens iteration and improves outcomes.

For more inspiration

Explore the Enscape gallery and keep building a small, shared library of glazing materials you trust; with “Replace with Enscape Material” and batch import/export, it’s easy to keep teams aligned as projects and hosts change.