This guide is designed to help you build 3D assets that are optimized for a 3D Swirl creative. For help creating 3D assets, you can contact a trusted 3D production partner.
Asset requirements
| Mesh File | GLB |
|---|---|
| Vertex limit | 30,000 or less |
| Texture formats | PNG (PNG-24, and indexed PNG-8), and JPG image formats |
| Texture size limit | 2048 x 2048 or smaller |
| Material | GLTF PBR Materials |
| Bone limit | 254 or less (includes non-weighted joints as well) |
| Bones per vertex limit | 4 bones per vertex or less |
| Asset size | 3 MB or lower |
| Draw calls | 15 or less unique object/material combinations. For best performance, limit to only 1 draw call. |
While there's no hard limit when it comes to polycount (number of faces of a 3D object), try to keep models below 12,000 polygons. Optimize the model for real-time rendering as much as possible. If something isn't seen or needed, don’t include it in the geometry. Many of these details can be added in the texture. For example, text, bevels, small screws, and so on.
Asset production best practices
Follow the guidelines below when preparing your 3D model for an ad.
3D models or meshes
| Model UVs |
Only a single UV set per mesh is supported. For character models, please mirror UV space when appropriate. For example, when modeling a tiger, don’t create two unique sides. Reuse one side and flip the direction to create the opposite side. |
|---|---|
| Model Pivot | Recommended: Place the origin of the model at either the geometric center or a centered position on the ground. (When published in an ad, people will rotate models around an automatically computed pivot point.) |
| Model Scale |
Important: Google Web Designer's 3D model working units are in meters. A distance of 1.0 units will be treated as 1 meter. Make sure to use the right scale to avoid rendering artifacts or problems with camera framing and animation. |
| Model Coordinate Space | Google Web Designer's 3D coordinate space is right-handed (+Z is the front of the object). Recommended: For ease of use, upload models that use the same coordinate system. |
Textures
| Texture Formats |
Google Web Designer supports PNG (PNG-24, and indexed PNG-8), and JPG image formats for 3D textures |
|---|---|
| Texture Best Practices |
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| Color Changing | If you intend to use color changing as a feature of the ad, the diffuse color texture should be set up as a desaturated version of the diffuse texture (for example, grayscale). When a color change is triggered at run time, the resulting diffuse color will be a multiplicative blend of this texture and the specified color, and lighting will then be applied based on that resulting diffuse color. |
Rigging
| Mesh Check | Ensure the mesh is scaled, positioned and oriented correctly before rigging. Set your scene units to 1 unit = 1 meter to match what Poly expects. |
|---|---|
| Joint Limit | A mesh should have no more than 254 joints. |
| Bone Influence Limit | Each vertex can only be affected by a maximum of four bones. Poly will discard any bone weights after the four most influential bones for each vertex. |
Optimizing Textures
JPG vs. PNG Compression
When to use JPG
Use JPG when a texture has a wide range of color values, gradients, and noise. JPG is a better format than PNG for maximizing file size reduction relative to loss of perceived visual quality.
This RGB texture compresses poorly as PNG, with noticeable banding even without reduction of color depth. JPG compression offers a more desirable tradeoff between visual quality loss and final compression ratio.
When to use PNG
Use PNG-8 when a texture has large solid areas of color with hard edges. For these textures, JPG compression will produce visible artifacts. PNG compression is more efficient than JPG at minimizing file size in these cases.
Tip: Consider using a material color instead of a texture when using large areas of solid color.
This is a best case scenario for PNG compression and texture downsizing. Not only are the color regions in this texture large and solid, they also have perfectly vertical and horizontal edges.