How to Create Correct Mirror Reflections in an AI Visualization? A Guide for SketchUp
A mirror in the raw SketchUp view is an empty, flat surface, so AI has nothing to reconstruct the reflection from and makes it up on its own. The "Mirrors" feature in the Raya plugin solves this before generation even starts: you point out the plane in the SketchUp window, and the plugin generates a reflection of the scene in its place. It's calculated locally, in a few seconds, and at no extra cost. Below I show the whole process and what actually changes in the finished visualization.
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Why AI draws mirrors incorrectly in visualizations
Empty mirror surfaces are one of the more common reasons why Raya misreads an interior. The AI model gets a flat image, not a 3D scene, so it can only reconstruct the reflection from what it sees in the uploaded view. In SketchUp, a mirror is just a plain panel of a single color and carries no information about what it reflects.
If you gave a photographer a photo of an interior with the mirror covered in gray cardboard and asked them to paint in the reflection, they'd also have to guess what's behind the camera. AI does exactly the same thing, just faster and with more confidence.
Sometimes it turns into a dark pane of glass, sometimes a fragment of an interior that isn't even part of the project. Input quality accounts for about 80% of output quality, and a mirror is the place where that shows up fastest. Below you can see an example where the mirror was generated as a dark, blurry plane.
The "Mirrors" feature in the Raya plugin for SketchUp
Since the problem lies in the input view, that's where it has to be solved. The "Mirrors" generates a reflection of the scene in the plane while you're still in the SketchUp window, before the view goes to generation. You'll find it in the plugin panel, under the "Generate" tab, right below the "Materials" section.
This isn't rendering. SketchUp doesn't calculate light physics — it just shows the scene mirrored across the plane of the mirror, which is why you see the effect instantly instead of after a few minutes of waiting.
That's where the second thing worth knowing before your first click comes from: generating reflections doesn't cost any credits. Everything is calculated locally on your computer and nothing is sent to Raya's servers. Credits are only used for the visualization generation itself, that is 2 credits for a 2K render and 4 credits for a 4K one.
You create an account for free, no card required, with 20 credits to start. The Raya plugin for SketchUp is free too, and mirror reflections work in every supported version of the program, meaning SketchUp 2020 and up. The SketchUp 2025 requirement only applies to inserting generated models into the scene, which we covered in the guide on how to make a 3D model from a photo in SketchUp.
How to pick mirrors step by step
Installing the plugin and logging in is a one-time formality, and marking the mirrors themselves takes just a dozen or so seconds. The whole procedure has three steps.
Turn on the Raya plugin for SketchUp — You open it by clicking the star icon or from the "Extensions" tab.
"Pick mirrors" — the plugin shows the number of selected planes, and you point out where they are.
"Done" or the Enter key confirms the selection and starts generating the reflections.
In selection mode, the plane under the cursor highlights in green, and clicking it again deselects it. The counter shows how many surfaces you've already marked, and the Esc key cancels the whole selection. The plugin handles mirrors hidden inside groups and components, and if a component appears multiple times in the model, it makes the selected instance independent so the reflection doesn't end up on every copy.
The baking itself takes a dozen or so seconds and is visible right in the SketchUp window. A red button then appears in the panel, "Remove mirrors", which restores the surface's original materials.
From there you work as usual. You click "Capture View", choose the frame's aspect ratio, set the lighting and materials, and then "Generate". A 2K render usually comes back after 20-40 seconds and you can download it as a PNG or JPG, with full commercial rights.
What a baked reflection changes in the finished visualization
Instructions are one thing, the effect on the render is another. The pair below comes from the same view of a tenement building: once without the baked reflection, once with it. These are two separate generations, so the sofa and countertop materials came out slightly different. Focus on the mirror surface itself.
Good example
Bad exampleWithout the "Mirrors" feature, the AI treated the mirror like a dark, smoked pane of glass. The frame came out great, and so did the molding around it, but inside the frame there's none of what the eye expects from a mirror hanging opposite the windows.
In the version with the baked reflection, the surface shows the ceiling with its molding, the cornice, and the window from the opposite wall. Even the mirror hanging across from it is reflected, creating a second reflection deeper in.
In a bathroom, hallway, or dressing room, a mirror often takes up half the frame and decides whether the client accepts the visualization without questions. The same mechanism applies to glass and shop-window panes too, so if you're just starting out and want to see the wider context, check out the guide on how to create an interior visualization with AI step by step.
What the "Mirrors" feature won't do
Mirror reflections have their limits, and it's better to know them upfront than to discover them during a client presentation. The reflection is baked for a single camera setup, so after rotating the view you click "Update", otherwise the surface will keep the previous shot.
The surface must be flat and either set in front of the wall or have some thickness. The plugin will skip rounded or beveled mirrors, and for a surface lying exactly in the same plane as the wall behind it, it will show a message and won't mark that surface.
Unfortunately, after restarting SketchUp, the plugin doesn't remember which planes were mirrors. The baked reflections stay in the model, but to refresh them you have to pick the surfaces again.
I hope that after reading this article, mirrors will stop ruining a good visualization at the last step. Picking the surfaces takes a dozen or so seconds and doesn't cost a single credit, so if you use SketchUp, definitely make use of this feature.
And if you want to try it on your own project, create an account and use your 20 free credits. No card is needed, and they're enough for about ten 2K visualizations — plenty to comfortably test mirrors in a few interiors.
