lumo 0.2.3 - Docs.rs

Lumo

Lumo is a CPU based multithreaded rendering engine. Made with the goal of learning Rust and physically based rendering :) The renderer is designed to be as modular as possible such that adding new features or algorithms is straightforward.

Features

Area light sampling
Path tracing with next event estimation
Microfacet BSDF with Beckmann and GGX normal distribution functions
Multiple importance sampling from VNDF for GGX
Disney diffuse BRDF with energy normalization used in Frostbite
Vertex and normal parsing from .OBJ files
Stratified sampling
kd-tree with SAH
Perlin noise generator

Usage

Once the repository is cloned, the examples/ folder contains scenes. To run the hello_sphere.rs example execute the command:

cargo run --example hello_sphere

The renderer can be configured either through its setter methods or partially through the CLI:

Usage: hello_sphere [-s <samples>] [-t <threads>] [-w <width>] [-h <height>] [-d]

Optional CLI configuration of renderer. Renderer setter methods have priority.

Options:
  -s, --samples     number of samples per pixel (defaults to 1)
  -t, --threads     number of threads used (defaults to all)
  -w, --width       width of the rendered image (defaults to 1000)
  -h, --height      height of the rendered image (defaults to 1000)
  -d, --direct      use direct light integrator instead of path tracing.
  --help            display usage information

Using the API

The hello_sphere.rs example is written as follows:

use lumo::*;
use lumo::tracer::*;
use glam::DVec3;

fn main() -> Result<(), png::EncodingError> {
    let camera = Camera::default();
    let mut scene = Scene::default();

    scene.add(
        Plane::new(
            DVec3::NEG_Y,
            DVec3::Y,
            Material::diffuse(Texture::Solid(srgb_to_linear(190, 200, 210)))
        )
    );

    scene.add(
        Sphere::new(
            8.0 * DVec3::Y + 1.5 * DVec3::NEG_Z,
            4.0,
            Material::Light(Texture::Solid(srgb_to_linear(255, 255, 255)))
        )
    );

    scene.add(
        Sphere::new(
            DVec3::ZERO,
            1.0,
            Material::diffuse(Texture::Solid(srgb_to_linear(0, 0, 255)))
        )
            .scale(0.3, 0.3, 0.3)
            .translate(0.0, -0.7, -1.5)
    );

    let mut renderer = Renderer::new(scene, camera);
    renderer.set_samples(36);
    renderer.render()
        .save("hello.png")
}

References

Gallery


Stanford dragon with 871K triangles and transparent microfacet BSDF. Rendered in 32 minutes using 40 threads of Intel Xeon Gold 6248. 4096 samples per pixel.


Cornell box displaying reflection and refraction. Rendered in 20 minutes using 20 threads of Intel Xeon Gold 6248. 4096 samples per pixel.

Circle of spheres