# Overview
**HTrace SSGI** is a fully dynamic screen-space global illumination system that aims for accurate and responsive indirect lighting with detailed secondary shadows. *** ## **Main Features** * **Full Integration into the Rendering Pipeline \[HDRP]**: automatic resource injection with no need for manual setup or package customization. HTrace SSGI overrides native indirect lighting resources, ensuring compatibility with other rendering effects. * **All Rendering Paths:** fully supports Deferred / Deferred+ / Forward / Forward+ rendering paths, with no visual or quality differences between them. * **All Light Sources:** compatible with all light types, including emissive materials that function as actual light sources and cast indirect soft shadows. Performance remains unaffected by the number of lights in the scene. * **Dynamic Environments:** designed for fully dynamic and procedural environments where objects, materials, and lighting can change in real time with no extra performance cost or preprocessing. * **APV Fallback & Enhancement:** natively supports Adaptive Probe Volumes as a fallback option. Enhances APV output by reducing light leaks and noise from low-resolution bakes, while adding fine GI details and occlusion from both static and dynamic objects. * **Advanced Denoising:** powered by a cutting-edge ReSTIR Validation algorithm that maximizes temporal responsiveness, while preserving small details and keeping indirect shadows sharp during spatial filtering. * **Scalability:** provides an adjustable Render Scale parameter for downscaled rendering, along with a wide range of options to fine-tune the effect and balance speed with quality. * **Infinite light bounces:** simulated through a feedback loop, with each frame capturing an additional bounce of light. * **Render Layer Mask:** selectively exclude objects from casting and/or receiving indirect lighting on a per-layer basis via the Render Layer Mask. * **VR Support \[HDRP]**: single-pass VR is supported. * **Open Code:** the code is open for modification. If you have questions about how it works, feel free to reach out to us on [Discord](https://discord.com/invite/zyjZkMe5Bv). ## Limitations and Requirements * Unity **LTS** releases are recommended; bug fixes for **non-LTS** versions are not guaranteed. * [**APV Fallback**](https://ipgames.gitbook.io/htrace-ssgi/settings-and-properties/global-settings#fallback) in **URP** requires **Unity 6000.0** or newer. * [**Exclude Casting**](https://ipgames.gitbook.io/htrace-ssgi/settings-and-properties/global-settings#exclude-casting) / [**Receiving**](https://ipgames.gitbook.io/htrace-ssgi/settings-and-properties/global-settings#exclude-receiving) options require **Unity 6000.0** or newer. * **Orthographic Camera** is untested and not guaranteed to work correctly. * **MSAA** is untested and not guaranteed to work correctly. ## Compatibility * **Currently tested APIs are:** DX11 and DX12, Metal * **Currently tested HDRP / URP versions are:** 14 and above. * **Currently tested Unity versions are:** from 2022.2 to 6000.3. *** {% embed url="" %}