SketchUp is one of the most used software for architectural modeling. And while users can now import SketchUp files directly into Unity, they still face issues with textures, duplicate assets, low FPS, and scaling.
This post will go over common issues users face when importing SketchUp into Unity, tips on how to fix them, and a new automated solution called Meshmatic.
Common issues when importing SketchUp into Unity
1. Errors exporting objects that were not originally from SketchUp
For many SketchUp users, it’s common practice to import objects from other 3D software (like Maya, 3ds Max and Blender) into their SketchUp model. For example, you may add furniture models from Maya into your SketchUp model.
However, issues can arise when exporting your entire SketchUp model, including objects that were added from Maya, into FBX. These include bad UV’s, duplicate normal, and inverted vertices. Dealing with bad geometry in Unity can be very time consuming and delay your visualization project.
2. SketchUp objects slow down FPS in Unity
Another common issue is that when SketchUp objects are imported into Unity, they are heavier to process and render. The reason is that when inside SketchUp, objects are combined into a single component, but when they are exported into FBX, these components are separated into thousands of individual objects and nodes. This decreases render speed and slows down FPS.
For example, a model of a foliage or tree inside SketchUp may count as a single component, but when imported into Unity, the branches and leaves are separated into thousands of different nodes, making your project harder to render, and slowing down your FPS.
3. Instantiated objects in SketchUp break off in Unity
While working inside SketchUp, duplicate objects, such as windows or chairs are instantiated. This means that any edits such as updating textures on one object will be automatically applied to the rest of the instantiated objects. This is a huge time saver!
The problem arises when you import your project into Unity, and duplicated objects become unique objects that are no longer instantiated. Not only does this make editing your scene more challenging, but it also decreases render speed and FPS.
4. Nested groups or multi-parent groups make editing challenging in Unity
After importing your FBX file into Unity, you may notice that your outliner has many nested groups, or “multi-parent” groups. This complicated outliner makes editing objects within these nested groups very challenging. For example, when you rotate a part, other parts sharing the same parent group will incorrectly rotate as well. This is something that you will need to manually fix in Unity.
Figure 1: Nested groups shown in Maya.
How to import Sketchup to Unity with textures
Whether you’re building a VR walkthrough or working on other visualization projects in Unity, importing your SketchUp model correctly into Unity and ensuring your textures and materials are imported correctly, is important.
To import your SketchUp file into Unity, make sure to follow these steps:
1. Export your file as FBX from Sketchup: The default FBX export settings in SketchUp, as shown below work for most projects.
Figure 2: Default FBX export settings in SketchUp.
2. Import FBX into Unity
3. Use LOD generator plugins inside Unity to create LOD’s: Since Unity does not have an LOD generator, you can use a LOD generator plug-in. Then, simply import your LOD’s into Unity in a single file.
4. Correct mesh problems such as nested groups: Like mentioned earlier, your outliner in Unity may have nested groups, which are problematic when you rotate a part, since all the other parts in the nested group will rotate as well. You have to manually correct this.
5. Generate UVs in Unity: If parts of your mesh have a non SketchUp source, you might encounter UV issues. Make sure to generate UV’s in another software or plug-in, and then import them into Unity.
Figure 3: UV’s generated in Maya.
If you are still having problems exporting your model correctly, Meshmatic can be a good option for you. Meshmatic automates the CAD to FBX conversion process, all while optimizing your model for optimal performance in Unity.
Do it faster: Import SketchUp to Unity with textures using Meshmatic
As you can see, there are a lot of manual steps to make sure your SketchUp file is ready for best performance in Unity. Meshmatic offers a solution to save you time by completely automating the SketchUp to Unity pipeline. Here are the benefits of Meshmatic:
- Meshmatic is an easy-to-use desktop software that speeds up the SKP to Unity pipeline. No 3D experience necessary
- Compatible with 10+ CAD formats, including SKP, 3ds Max, and more
- Automated SKP to FBX conversion, while preserving colors, textures and materials
Meshmatic automatically solves common SketchUp to Unity import issues
The common issues we covered earlier can be resolved quickly and automatically with the help of Meshmatic. Here are some tips on how you can use Meshmatic to easily solve these issues:
Fix non-SketchUp assets
Assets that are not originally designed in SketchUp can have issues such as detached faces, and missing vertices. Before importing an object from a different 3D software, like Maya, into SketchUp, we suggest using Meshmatic to optimize the asset into an optimized mesh, and then importing it into SketchUp.
Improve FPS in Unity with Meshmatic
A large and complex SketchUp file will likely decrease render speed and slow down FPS in Unity. Meshmatic’s optimization tools, particularly the “Combine All” tool, can help resolve these issues. The “Combine All” tool automatically merges all the meshes in your scene into a single object, helping reduce file size and speed up your FPS.
Instantiate duplicates with Meshmatic
Meshmatic’s “Duplicate Instantiator” tool automatically detects duplicates and creates instances of them. This will make editing your file in Unity a lot easier, because all the changes you make to a one object, will be automatically applied to its instances.
Figure 4: Duplicate vertices in the identical chairs are instanced with the help of Meshmatic.
Automatically generate LOD’s
Meshmatic’s LOD generator tool automatically creates LOD’s for your file. The LOD’s are saved in a single file for easy import into Unity.
Figure 5: LOD’s generated in Meshmatic are easily imported into Unity.
Correct nested groups in Unity outliner
The “Outliner Roll-up” tool in Meshmatic automatically corrects nested groups. This tool flattens nested groups by calculating each node’s transformation in the scene, so it’s no longer referenced by its many parent groups. This simplifies the outliner and makes it easier to edit the project.
How to integrate Meshmatic into your SketchUp to Unity pipeline
If you are interested in testing a new solution that converts SketchUp to FBX, corrects errors in the mesh (like bad UV’s, inverted vertices and more), you can download a 7-day free trial to test Meshmatic here.
Start using Meshmatic in a few simple steps:
- Download your free trial
- Install Meshmatic on your PC
- Import your SketchUp model into Meshmatic
- Select the Game Engine profile from the import wizard. Meshmatic will automatically convert and clean up your SketchUp file into an optimized FBX.
- Export your FBX model for Unity
Figure 6: Meshmatic’s Gaming profile optimizes 3D files for optimal performance in Unity.
If you have any feedback, feel free to leave it below!
Download a 7-day Meshmatic trial here.