Gaussian Splat Annotations and Viewer

This repository contains the working changes for the Gaussian Splat Annotations and Viewer that was a Master Project in Media Technology M.Sc. in Winter Term 2023/2024 at TH Köln.

There is a working 🚀 live version of current main branch 🚀 which is deployed to GitHub Pages.

Run locally

To run the application yourself, you need NodeJS on your Computer and available in your PATH environment. In the root folder (the one with this Readme), run npm install to get the dependencies that were defined in package.json. This will also install the devDependencies which are needed to compile the project.

Now, you can download the splat files which contain the scene data. Download the splat models to the respective folders in public/scenes and rename them to scene.splat each:

• https://photos.volkland.de/gsplats/bonsai-7k-raw.splat
• https://photos.volkland.de/gsplats/bicycle-7k.splat
• https://photos.volkland.de/gsplats/garden-7k.splat
• https://photos.volkland.de/gsplats/wohnzimmerAntimatter15-converted.splat
• https://photos.volkland.de/gsplats/wohnzimmerPolycam-converted.splat

You can also use the following curl commands in a terminal:

curl -o public/scenes/bicycle/scene.splat "https://photos.volkland.de/gsplats/bicycle-7k.splat"
curl -o public/scenes/bonsai/scene.splat "https://photos.volkland.de/gsplats/bonsai-7k-raw.splat"
curl -o public/scenes/garden/scene.splat "https://photos.volkland.de/gsplats/garden-7k.splat"
curl -o public/scenes/wohnzimmerAntimatter15/scene.splat "https://photos.volkland.de/gsplats/wohnzimmerAntimatter15-converted.splat"
curl -o public/scenes/wohnzimmerPolycam/scene.splat "https://photos.volkland.de/gsplats/wohnzimmerPolycam-converted.splat"

With limited space or bandwidth, you can also just download a subset of the scenes and expect a broken page when opening the other scenes.

Now that everything is ready, you can run a webserver and open the provided link. It will respond to code changes by reloading (parts of) the page:

npm run dev

You can also create a static build of the application to include in your website. The build will use a base url from which it will derive all subpaths, so you probably want to change it in vite.config.js. To create a static build, run npm run build and copy the files in the dist folder to their place on the web server.

Adding a new scene

1. Think of a slug for your scene. It will be visible to viewers of the webpage in the URL and can not contain spaces.
2. Extend src/comments/annotations-storage.ts:
   1. type AvailableScenes with the new slug.
   2. Set a human-readable name in const sceneNames.
   3. Define the annotations to the scenes in const annotationStorage. This can also be an empty array, but it can not be undefined.
3. Add the .splat file of your scene to public/scenes/$slug/scene.splat.
   • If you only have a ply file, you can use the converter that is linked in the footer navigation of the webpage.
   • .splat files are ignored by git since they are too large and in a binary format. Save the file on some web space and update the readme section and your deployment script (i.e. .github/workflows/vite-deploy.yml).
4. Add a screenshot of your scene to public/scenes/$slug/cover.png. It should have sufficient resolution to look good in the catalogue view.
5. Extend src/GSplatPrograms/prepare-scene.ts:
   1. Define scene modifications in const scenePreparations. This can be empty in the beginning or a reference to identity.
   2. Translate the scene modification to a positional modification in const splatPositionModification. This can be a reference to identity. This is important to translate the position of a splat to its world coordinates, i.e. when attaching an annotation to it. It is not necessary to scale the vector.
   3. If you want to, you can add a helpful arrow (i.e. to define a rotation axis) to the scene. Use the function helpfulArrow for this and fill it with your own data.

After extending the type definition, the application will not build until you extend the rest of the items. This is expected and here to help you.

Debug Mode

There is a debug mode which you can activate in the Scene-Detail-Page by clicking the link on the top right of the canvas. It comes with the following features:

• The current Camera Position in gsplat.js and three.js world coordinate spaces are noted in the bottom of the page.
• A grid along the "floor" of both renderers is inserted. The gsplat renderer creates a red grid, the three.js renderer creates a green grid. The green grid is moved a little bit down so its easier to see both grids.
• The primary axes (1 in each direction) are rendered. These can be a little hidden, its recommended to uncomment the grid calls when you need the axis information.
• A sunflower is added to the three.js scene to have a more interesting, visual object in the scene. The sunflower will "look" at positive X in gsplat.js coordinates, so negative X in three.js coordinates.

Attributions

• Sunflower Polygon: "Sunflower" by Poly by Google, licensed under CC-BY 3.0.

Masterprojekt im Studiengang Medientechnologie M.Sc. an der TH Köln. Contact: jvolklan@th-koeln.de.