Ethz Raytracer

A raytracer for the computer graphics course at ethz.

Live demo

The renderer is deployed to https://ethz-raytracer.firebaseapp.com/

Alternatively, the repository can be cloned from https://github.com/lukaselmer/ethz-raytracer , but then the code first has to be compiled (see compilation instructions).

Compilation instructions

This raytracer is written in Coffeescript, which is very similar and compiles down to JavaScript. To compile the coffeescript sources:

• Install NodeJS
• npm install --force
• npm install -g grunt-cli
• npm run build

You can also use the npm start command to automatically build the files when the coffeescript files change.

Running the tests:

• Unit tests: grunt karma:unit (run automatically when the JS files are changed, works fine with grunt watch)
• CI tests grunt karma:ci (run only once, for continuous integration)

Code structure

Overview of the public folder:

public
├── data (data used in C2 and C3)
│   ├── Earth.tga
│   ├── EarthNormal.tga
│   ├── Moon.tga
│   ├── MoonNormal.tga
│   ├── ateneal.obj
│   ├── ateneam.obj
│   ├── dragon.obj
│   ├── mini.obj
│   ├── neoSimian-mech.obj
│   ├── neoSimian-organic.obj
│   ├── sphere.obj
│   └── teapot.obj
├── index.html (the main file to be opened in the browser)
├── lib (libraries used for the raytracer)
│   ├── bootstrap.min.js
│   ├── jquery-1.10.2.min.js
│   ├── read_obj.js
│   ├── read_tga.js
│   ├── startup.js
│   └── sylvester.src.js
├── out (compiled JS files)
│   ├── compiled.js
│   ├── compiled.js.map
│   ├── compiled.min.js
│   ├── compiled.src.coffee
│   ├── compiled.src.js
│   ├── compiled.src.map
│   ├── v1_compiled.js
│   └── v1_compiled.js.map
├── output (rendered images)
│   ├── cg-ex2-lukaselmer-A1.png
│   ├── cg-ex2-lukaselmer-A1B1.png
│   ├── cg-ex2-lukaselmer-A1B1B2.png
│   ├── cg-ex2-lukaselmer-A1B2.png
│   ├── cg-ex2-lukaselmer-B3.png
│   ├── cg-ex2-lukaselmer-B3B1.png
│   ├── cg-ex2-lukaselmer-B3B1B2.png
│   ├── cg-ex2-lukaselmer-B3B2.png
│   ├── cg-ex2-lukaselmer-B4.png
│   ├── cg-ex2-lukaselmer-B4B1.png
│   ├── cg-ex2-lukaselmer-B4B1B2.png
│   └── cg-ex2-lukaselmer-moduleid.png
└── src (source code)
    ├── BoundingBox.coffee
    ├── Camera.coffee
    ├── Color.coffee
    ├── Intersection.coffee
    ├── Light.coffee
    ├── LightIntensity.coffee
    ├── MeshLoader.coffee
    ├── NormalMap.coffee
    ├── Octree.coffee
    ├── Ray.coffee
    ├── RayConfig.coffee
    ├── RayTracer.coffee
    ├── ReflectionProperty.coffee
    ├── Scene.coffee
    ├── SceneLoader.coffee
    ├── Texture.coffee
    ├── figures
    │   ├── Cylinder.coffee
    │   ├── Ellipsoid.coffee
    │   ├── Hemisphere.coffee
    │   ├── Mesh.coffee
    │   ├── MultipleObjectsIntersection.coffee
    │   ├── Plane.coffee
    │   ├── Sphere.coffee
    │   └── Triangle.coffee
    └── helpers.coffee

Unit Tests

There are now some basic unit tests. To execute the tests run grunt karma. Make shure you run a browser on port 63342, otherwise the texture tests will fail.

Implemented Features

The following features have been implemented:

A1: Basic features

• Ray casting
• Ray-object intersection
• Shadows
• Phong lighting model

B1: Specular reflection and specular refraction

The algorithm is programmed recursively.

B2: Anti-aliasing

Anti-aliasing is implemented with a regular grid. Currently, there are no textures and with the current setup, no unwanted aliasing could be observed.

B3: Quadrics

The two quadrics are implemented.

B4: Boolean operations

The boolean operations are implemented.

C1: Stereoscopic rendering

Is implemented, but yet untested due to the lack of stereoscopic glasses.

C2: Texture mapping and bump mapping

Is implemented with

• Surface mapping
• Anti-aliasing
• North poles are on top
• Bump mapping

C3: Triangle meshes

The triangle meshes are implemented and some additional objects have been rendered.

D1: Octree

Is implemented. Without the octree, rendering meshes is nearly impossible. The depth of the octree can be configured, and should be set high of objects with many faces.

D2: Area lights

The area lights for the shadow rays are implemented. The monte carlo integration is done with a jitter algorithm. Additional algorithms could be implemented.