1. Background
WANNA rendering engine is capable of showing beautiful gems like diamonds or sapphires. Some of this beauty is proprietary and requires special model preparation; this article describes how to achieve the desired effect.
2. Preparation
3. Suggested workflow
The best way to model items with repetitive gems is to use instances. Unfortunately not all modeling tools support them, so we suggest the following workflow to work around it.
3.1 Base Model
- Create base geometry in any 3D tool.
- Do not add gems at this stage.
3.2 Texturing
- Texture 3D model using Substance Painter or any other software.
- Export textured model to gltf.
- Import into Blender.
3.3 Adding Gems
- Add gemstones from the archive.
- Reset transformations (temporary workaround).
- Use a single mesh as the source, and make all gemstones of the same cut its instances.
- Do not bake AO under gems (prevents black spots).
- Leave a bit of space between gems and materials that hold them to avoid coplanar mesh.
- All gems should be subnodes of the top level main node to correspond with General model requirements for 3D Viewer
3.4 Naming Materials
Diamonds/dispersion materials: wanna_diamond_XXX.
Coloured gems (sapphire, ruby, emerald, etc.): wanna_colored_gem_XXX.
3.5 Base Material Parameters
Set base materials parameters to the following for all gems. If you are using cuts from our archive, they are already preset there.
Base color |
According to the gem color on the reference |
| Metallic | 0 |
| Specular | 0.5 |
| Roughness | 0 |
| IOR corresponding to gem | See pixelandpoly.com/ior.html |
| Transmission | 1 |
| Blend Mode | Opaque |
3.6 Export
- Export model to glTF with Vertex Colors disabled.
- Upload to WANNA Studio.
- Open Edit → Gems Setting tab.
4. Gems Parameters in WANNA Studio
4.1 Select a material to edit
In Gems Settings, choose the gemstone material you want to edit (e.g., wanna_diamond_1 or wanna_colored_gem_1). All controls below apply to the selected material.
4.2 Light behaviour
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Number of bounces: controls how many times light reflects inside the gem.
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Roughness, Metallic, Specular: standard PBR controls.
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4.3 Optical Properties
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Index of Refraction (IOR) Use physically accurate value for your gem. https://pixelandpoly.com/ior.html |
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Specular (KHR_materials_specular) Controls specular intensity and allows a slight colour tint. Thickness factor — use the actual stone thickness in the same units as in the model. |
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Thickness adjustment for watch sizes Thickness factor — use the actual stone thickness in the same units applied when creating a model. |
If you are creating different watch sizes for try-on, use the following coefficients:
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Attenuation Attenuation distance regulates how deep light needs to go through before it is absorbed (Color intensity). Attenuation color is basically gem color. |
5. Finalisation
Press Save All to store changes in the optimised glTF model.
