3dstreet-assets-source
This repository contains the source files for 3DStreet, an open-source web-based tool for visualizing safer streets.
This repo contains source files. For production ready assets, see 3DStreet-Assets-Dist which contains compressed glTF models used in the 3DStreet app and available on our CDN at assets.3dstreet.app.
License
Objects are licensed CC-BY-NC-SA (Creative Commons Non-Commercial Share Alike) unless otherwise noted. See the LICENSE file for details
Installation
Simply clone the repo and work directly on the included Blender files.
Folder Structure
Materials
This folder contains .blend files that contain common materials that will be shared across different models. The textures subfolder contains any texture dependencies.
Models
The models folder contains subfolders for individual assets. Each subfolder contains the .blend and any unique dependencies and resources. These models may contain links to materials from .blend files in the Materials folder if they use any common materials.
Sets
Sets are .blend files that contain links to collections from blend files in the Models folder. Sets allow multiple models to be exported together for the 3dStreet application efficiently and without duplicated dependencies. The exports folder contains gltf and/or glb files ready for use in the application.
Diagram
3DStreet Modeling Best Practices
File Setup
- Use Blender 2.92 or later
- make sure to 'load factory settings' before creating new Blender files for the pipeline.
- Purge the model of all orphaned data
Object Standards
- Models must be correctly scaled in real-world metric units.
- Models must be oriented so that +Z is up, and they face forward in the -Y direction.
- All static parts of an object should be joined into a single mesh.
- All transforms should be applied and the model origin should be (0,0,0)
- Each object should be placed in its own Collection with the same name. This allows models to be referenced into Set files more easily.
Geometry Standards
- Vertices should be welded.
- Normals should look correct in Blender viewport. Some models may have 'custom split normal data' that need to be cleared.
- For geometry using normal maps, ensure that no UV islands have a scale of '0' as this causes issues in WebGL renderers.
- Meshes should have just one UV map labeled "UVMap"
Material Standards
- Remove all materials with solid diffuse colors and replace them with the linked color atlas in the Materials folder. Adjust the UVs as needed to color the mesh as intended.
- Textures specific to the model should go in the model’s textures folder. Atlas textures when appropriate (signage and graphics, non-repeating textures)
- Textures should have power-of-two dimensions and not exceed 2048px. Make textures as small as possible without compromising visual quality. Usually 256-512px is sufficient.
Dependencies
The Blender files were created in Blender 2.92.0
Video Tutorial
This step-by-step video tutorial by @mwbeene is perfect for any level of Blender experience (even beginners) to learn the 3DStreet model pipeline. It can also be useful for other web-based 3d apps outside of 3DStreet.
Converting glTF to glb with Draco compression
First option is to use the gltf-pipeline command-line tool from Cesium team.
- Install gltf-pipeline globaly (with -g parameter). Use instruction from https://www.npmjs.com/package/gltf-pipeline?activeTab=readme. Install Node.js if you don't already have it, and then:
npm install -g gltf-pipeline - To convert glTF file into glb (with Draco compression) use command:
gltf-pipeline -i model.gltf -o modelDraco.glb -d
Another option is to use the gltf-transform command-line tool from Don McCurdy:
- Install gltf-transform globaly (with -g parameter). Follow instructions from https://gltf-transform.donmccurdy.com/cli.html. Install Node.js if you don't already have it, and then:
npm install --global @gltf-transform/cli - To convert glTF file into glb (with Draco compression) use command:
gltf-transform draco model.gltf modelDraco.glb
In recent test as of August 2023 gltf-pipeline resulted in smaller file size