The Radiance model repository is a free, open-source repository of 3D models, textures, lighting files, and Radiance material definitions which can be used in scenes.
It is fairly common to find 3D models in various formats online which have materials defined for popular rendering engines. However, when producing renders with Radiance, we are interested in 3D models that are to scale, have a certain level of detail built into it, and also have materials, lights, and textures defined in a very specific way. This means that existing repositories are not too useful. Here's what you'll find in this repository:
- All models are a digital twin of a real-life physical product. This repository must have photometrically correct material definitions, and so it is not possible to have an imaginary object, as we cannot scan that material. Where possible, the real product will be named and linked to so you can check what it physically looks like.
- All models are in metres. Relative scale is important in lighting simulation, and so we have chosen metres as a standard.
- All models have calibrated materials. All material definitions are defined in Radiance syntax and obtained from measurements of the real life object, such as through the macbethcal method. Any approximations in the material will be described explicitly to you so you can make an informed judgement. It is encouraged to be critical of the measurements and verify measurements are correct. If you have an improvement, please share it so that everybody benefits (as required by CC-BY-SA).
- All lights are real lights. Any significant light would be represented by an
.iesfile, with a careful definition of the luminaire. - All models are geometrically and texturally detailed. This repository has the dual purpose of being validated, as well as aesthetically pleasing (without sacrificing correctness). This means that we aim for detailed geometry (to a degree that does not prohibit the simulation), and rich textures (in the CG artist sense of the term) with UV mappings. Textures will be calibrated to ensure they still represent the average RGB of the material.
- All models have a preview picture. These preview pictures give only a rough idea of what the model contains, but are not a photometrically correct simulation and will therefore look fake. The model will look different when placed in a true life environment.
- Models are categorised using the IFC4 ISO BIM standard. As the purpose of these lighting simulations are mostly for simulations of the built environment, we have chosen to use BIM classifications.
- All models are open-source and open-data. Not only is this entire repository under CC-BY-SA, any source models with their parametric data are retained in open-source formats, such as
.blendBlender format and.objfiles both being provided. - All assets follow the RFHS for easy reuse. The Radiance Filesystem Hierarchy Standard is a proposed file organisation standard to organise and reuse assets across scenes in Radiance, so using a model is a simple as a single
xformline of code.
I have written a little bit about why we need a Radiance free 3D model repository, which describes some of my motivations behind hosting this repository. I hope these ideas resonate with you.
Contributing
You are encouraged to contribute to this repository! You can contribute by:
- Hosting a mirror of the repository. Yes, unlike other repositories, this is encouraged!
- Adding your own objects to the repository. Please contact me to add it.
- If you own a product that a model here represents, please don't hesitate to scan your own materials and critically analyse how to improve the materials defined here. Any changes that improve the accuracy of these models are very welcome.