Strolle

Strolle (from strålspårning) is a real-time renderer with support for dynamic global illumination:

Strolle's goal is to experiment with modern real-time lighting techniques such as ReSTIR and see how far we can go on consumer hardware, especially the one without dedicated ray-tracing cores.

Strolle comes integrated with Bevy, but can be also used on its own (through wgpu).

Status: Experimental, no official release yet (see the demo below, though!).
Platforms: Windows, Mac, Linux & WebGPU.

• Gallery
• Examples
• Usage
• Roadmap

Gallery

(note that currently there's no denoiser for specular lighting)

Examples

Dungeon

$ cargo run --release --example demo

Shows a dungeon tech demo, as in the example above.

Use WASD to move, mouse to navigate the camera, and:

• H/L: Adjust sun's azimuth,
• J/K: Adjust sun's altitude,
• F: Toggle flashlight on/off,
• M: Toggle diffuse/specular materials,
• T: Remove textures,
• 1: Show the final, composed image¹ (default),
• 2: Show direct-diffuse lighting only¹,
• 3: Show direct-specular lighting only¹,
• 4: Show indirect-diffuse lighting only¹,
• 5: Show indirect-specular lighting only¹,
• 8: Show BVH heatmap,
• 9: Switch camera to a path-traced reference mode (slow),
• 0: Switch camera to Bevy's renderer,
• ;: Toggle camera's controls on/off - useful for taking screenshots.

¹ press the same key again to toggle denoising on/off

Model thanks to:
https://sketchfab.com/3d-models/low-poly-game-level-82b7a937ae504cfa9f277d9bf6874ad2

Cornell Box

$ cargo run --release --example cornell

Usage

Bevy

Currently supported Bevy version: 0.12.1.

1. Add Strolle to your dependencies:

   [dependencies]
   bevy_strolle = { git = "https://github.com/patryk27/strolle" }

2. Add a patch to work-around a bug in Naga:

   [patch."crates-io"]
   naga = { git = "https://github.com/Patryk27/naga", branch = "v0.13.0-strolle" }

3. Setup & enjoy!

   App::new()
       /* ... */
       .add_plugins(StrollePlugin);
   
   commands
       .spawn(Camera3dBundle {
           camera_render_graph: CameraRenderGraph::new(
               bevy_strolle::graph::NAME,
           ),
           camera: Camera {
               hdr: true,
               ..default()
           },
           ..default()
       });

Note that Strolle completely overrides Bevy's camera graph, so you can't use a Strolle camera together with Bevy's effects such as bloom or TAA - fragment and vertex shaders won't work as well.

Also, Strolle is not optimized well towards higher resolutions - on non-high-end GPUs, it's recommended to stick to ~800x600 and upscale the camera instead (see the demo.rs here).

Roadmap

https://github.com/Patryk27/strolle/issues?q=is%3Aissue+is%3Aopen+label%3AC-bug%2CC-feature

Algorithms

Notable algorithms implemented in Strolle include:

• ReSTIR DI
• ReSTIR GI
• SVGF
• A Scalable and Production Ready Sky and Atmosphere Rendering Technique

License

MIT License

Copyright (c) 2022 Patryk Wychowaniec & Jakub Trąd