diff options
Diffstat (limited to 'src/blog/2021-10-27.md')
-rw-r--r-- | src/blog/2021-10-27.md | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/blog/2021-10-27.md b/src/blog/2021-10-27.md new file mode 100644 index 0000000..06b9a0d --- /dev/null +++ b/src/blog/2021-10-27.md @@ -0,0 +1,34 @@ +# Ray marching in Rust :rust: ! +I'm currently learning Rust for fun and re-writing my [ascii-renderer](https://github.com/eug-vs/ascii-3d-renderer) from Python :python:. I'm using Ray Marching this time, here's how it looks (if you are on mobile, use desktop version of the site): + +[![asciicast](https://asciinema.org/a/jsDqGeMkRwLeYhVIMqNbaec0M.svg)](https://asciinema.org/a/jsDqGeMkRwLeYhVIMqNbaec0M) + +You can see that Ray Marching allows for some cool stuff like smooth surface blending and proper shadowing. + +# Ray marching +Usually 3d renderers use a triangular mesh to describe objects in a scene. In Python version of `ascii-renderer` I defined each object as a set of points +(i.e object is defined by a function `__contains__` that determines whether the given point is in this object). It allowed me for some cool Ray Tracing stuff, but that was just me toying around. + +Behold - Ray Marching! It's a cool rendering technique where you describe your scene with a *Distance Field* - each point in this field contains a distance from that point to the scene. +Well, actually it's a *Signed Distance Field* - the distance to the object is considered negative *inside* the object, and positive *outside*. + +What's cool about Ray Marching is that since the whole scene is defined with mathematical expression, I can apply any mathematical transformations to it. For example I can make an object wavy +using a `sin`, or make it repeat forever with `%` operator. Also, `SDF` allows for different ways to combine objects - I can find a `union`, `difference`, and `intersection` for free! + + + +## Performance +Currently it's rendering 4 shapes at ~19 FPS, which is pretty bad. That's probably due to my dirty and inefficient code :laughing: - I'm nowhere near a good understanding of Rust :rust: patterns. + +My goal is to render 8 shapes at 24 FPS: + - 24 FPS is OK for a human eye + - 8 distinct shapes is usually enough to create a complex scene (ray marching allows for cool tricks that can multiply amount of your shapes without performance decrease) + + +# Plans + - Cleanup the code and increase performance + - Build an actually usable API + - Use `ncurses` instead of just printing to `STDOUT` + - Create an `ncurses` GUI for building a scene + - Allow importing/exporting scenes in `JSON` + - Do some magic :star: and expose API to the browser using `WebAssembly` |