pinkuburu/ltcgi

Optimized plug-and-play realtime area lighting using the linearly transformed cosine algorithm for Unity/VRChat.

LTCGI

LTCGI is an optimized plug-and-play realtime area light solution using the linearly transformed cosine algorithm for standalone Unity and VRChat. Free to use with attribution. It can utilize the Unity build-in lightmapper or Bakery for realistic shadows on static objects.

Check out the official website for documentation and a "Getting Started" guide! (https://ltcgi.dev)

Consider the attribution requirements. Check the Releases tab for downloads.

You can also download the standalone demo app pictured above to try it out for yourself.
Alternatively, join the demo world in VRChat.

Read the FAQ before asking for help anywhere! Once you've done that, feel free to join my Discord and ask for help: https://discord.gg/r38vJd2DuJ

Download

For VRChat, you can install LTCGI via the Creator Companion from my VPM repository:

⬇️ Creator Companion/VPM Install

For standalone Unity, you can import LTCGI as a git package with the URL: https://github.com/PiMaker/ltcgi.git

Adapters for various VRChat video players are still distributed as unitypackages from the Releases tab.

Supported shaders

To use LTCGI, all objects that should receive lighting must use a compatible shader. Currently compatible ones are listed below. If you implement LTCGI into your shader, feel free to send a PR to be included.

• ORL Shader Family by @orels1
• Silent's Filamented
• Mochie's Unity Shaders
• Hekky Shaders
• z3y's Shaders
• Basic "Unlit" Test Shader (included)
• Surface Shader (included)

Attribution

According to the License you are free to use this in your world, but you need to give credit. You are free to do so in whichever way, but you must provide a link to this GitHub repository, such as to fulfill the imported license of the LTC example code used as a base for this project.

For your convenience, a prefab called LTCGI Attribution is provided in the package.

If you don't want to use it, instead display text similar to the following:

This project/world uses LTCGI by _pi_, see 'github.com/pimaker/ltcgi'.

Licensing

The LTC algorithm

Based on this paper:

Real-Time Polygonal-Light Shading with Linearly Transformed Cosines.
Eric Heitz, Jonathan Dupuy, Stephen Hill and David Neubelt.
ACM Transactions on Graphics (Proceedings of ACM SIGGRAPH 2016) 35(4), 2016.
Project page: https://eheitzresearch.wordpress.com/415-2/

Read more

LTCGI

This project is made available under the terms of the MIT license, unless explicitly marked otherwise in the source files. See LICENSE for more.

The following files are licensed explicitly, and may not be modified or used in commercial projects, but can be redistributed and displayed otherwise, provided this license is kept:

• Propaganda/pi_graffiti.png
• Propaganda/ltcgi_graffiti.png