shawnecy / bonsai

A voxel engine in a pot

Welcome to Bonsai!

Bonsai is a 3D voxel-based engine built with the intention of writing both fast-paced arcade games and tile/turn-based RPGs

Bonsai, and nearly all it's dependencies, are written completely from scratch. One external dependency is the C runtime library for startup, and a small handful of trig functions (sin, cos, atan2). I have a back-burner task to remove the CRT entirely, though it's unclear when/if I'll get around to it.

The only requirements to build and run Bonsai are an OpenGL 3.3+ driver, C++ compiler, and a few appropriate system headers.

Renderer Features

• Deferred Shading
• HDR Lighting
• Order-independant Transparency
• Lighting Bloom
• Shadow Mapping
• Screen Space Ambient Occlusion

Engine Features

• Hot Code Reloading
• MT Job System
• Entities
• Collision
• Transparent & Emissive Particles
• UI Framework
• Asset Loaders
• Terrain Generators
• Primitive Physics

Performance Profiler Features

• Manual Instrumentation
• Memory allocation tracing
• Per frame call-graph tracing
• Context Switches (windows only)
• Physical Core (windows only)

Getting Started

Building

See the docs on the build process.

Wishlist

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Renderer

[ ] SSR : https://lettier.github.io/3d-game-shaders-for-beginners/screen-space-reflection.html

[ ] Screen-space lines : https://mattdesl.svbtle.com/drawing-lines-is-hard

[ ] Better shadows : https://developer.nvidia.com/gpugems/gpugems3/part-ii-light-and-shadows/chapter-8-summed-area-variance-shadow-maps

[ ] Screen Space Shadows : https://panoskarabelas.com/posts/screen_space_shadows/

[ ] Motion Blur : https://developer.nvidia.com/gpugems/gpugems3/part-iv-image-effects/chapter-27-motion-blur-post-processing-effect

[ ] TAA?

[ ] FXAA : http://blog.simonrodriguez.fr/articles/2016/07/implementing_fxaa.html

[ ] Water : https://www.youtube.com/watch?v=5yhDb9dzJ58

[ ] Fluids : https://andrewkchan.dev/posts/fire.html

[ ] Remove meshing entirely? https://www.youtube.com/watch?v=4xs66m1Of4A

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Terrain

[ ] Erosion simulation

• https://inria.hal.science/hal-01262376/document
• https://xing-mei.github.io/files/erosion.pdf
• https://nickmcd.me/2020/04/15/procedural-hydrology/

[ ] Biomes

• https://en.wikipedia.org/wiki/Holdridge_life_zones

[ ] Meshing

• Isotropic surface meshing
• https://graphics.stanford.edu/courses/cs164-10-spring/Handouts/isotropic.pdf
• https://inria.hal.science/inria-00071612/document

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Assets

[ ] MCA importer

• https://github.com/GabeRundlett/gvox/blob/old/src/formats/minecraft.cpp

[ ] Sound : mp3, ogg, ..? decompresser

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Datastructures

[ ] Better low-discrepency sequences : https://blog.demofox.org/2017/05/29/when-random-numbers-are-too-random-low-discrepancy-sequences/

[ ] Better hash function! : https://nullprogram.com/blog/2018/07/31/

[ ] Better GPU hashing! : https://arugl.medium.com/hash-noise-in-gpu-shaders-210188ac3a3e

[ ] Hash-trie as alternative to a table : https://nullprogram.com/blog/2023/09/30/

[ ] Octree ? https://graphics.tudelft.nl/Publications-new/2020/CBE20/ModifyingCompressedVoxels-main.pdf

[ ] Better floating-point rng : https://www.corsix.org/content/higher-quality-random-floats

[ ] Better greedy meshing? https://www.youtube.com/watch?v=4xs66m1Of4A

[ ] More interpolation goodies : https://paulbourke.net/miscellaneous/interpolation/

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Profiler

[ ] Improve the ETW layer : https://github.com/bombomby/optick/blob/master/src/optick_core.win.h