QUESTION: I imported my .FBX or .OBJ file, but the scene is running very slowly. How do I optimize my model for better AR & VR performance?
A. Edit your model in your native design program
There are several design tricks that you can use to make sure that you get the best possible result when you import OBJ or FBX files for AR/VR, but most of them occur in the native design program. Fortunately, most of these 'tricks' are generally good practice for any designer or artist.
Here are some easy tips for reducing the complexity of the model without compromising your original design:
Reduce the Number of Objects
Aim to keep the number of objects as low as possible (ideally less than 10). If necessary, combine the static geometry of the objects in your scene. A high number of objects can slow down real-time rendering – especially on mobile. BRIO will try to auto combine objects with the same materials if there are more than 10.
For the best performance when you create a 3D model for AR, keep it at the lowest possible object count.
Reduce the Number of Polygons
Try not to exceed 300K polygons in your final scene. This means that you will need to reduce your poly-count in the native design program before exporting for AR or VR, especially if you are adding multiple models to a single scene.
300K polygons are the rough limit for high-end smartphones, but older phones may have trouble rendering even at that volume.
Limit Texture Sizes
Use as few texture maps as possible and do not exceed a size of 2048×2048 pixels. Instead, try to use compressed textures like .jpeg, and re-size your images to achieve the power of two (POT) whenever possible (256×256, 512×512, etc.)You can also reduce the number of skinned objects for animation, and reduce the poly-counts for skinned objects.
When you do this, the textures that are POT will be optimized for AR or VR presentation.
Grouping / Limiting the Number of Materials
By grouping your materials and textures, you can drastically reduce your scene’s size and complexity, particularly if your model is made with several materials.
For example, if you have created a bicycle in 3DS Max, you can group the rubber on the wheels and the rubber handlebar grips if they are the same material. When you do this, you will see no change to the final model, but the performance in AR or VR will be more seamless because you have reduced the complexity of the initial model.
Tip! You can make your scene lighter by turning off effects - this is especially helpful on mobile.
Check out our What Platforms, Devices and Browsers are Supported in BRIO? article.