TUD Logo

TUD Home » ... » WS 05/06 » Global Illumination » Raytracer GLB

Computer Graphics

Raytracer GLB

Komplexpraktikum Globale Beleuchtung - Wintersemester 2005/06
Lehrstuhl für Computergraphik und Visualisierung
Betreuer: Thomas Räckel


For the course "Komplexpraktikum Globale Beleuchtung" a raytracer had to be programmed in C#. It had to implement one method for global illumination. The following features were obligatory:

  • Recursive raytracing with reflexion, refraction and shadows
  • Primitives: sphere, plane, box, triangle
  • Pointlightsource, directional lightsource
  • Phong material and image textures
  • Perspective camera
  • Reading XML3d scenefiles
  • Creating appealing scenes
Further features could be chosen by the team members. Especially an efficient data structure and a method for global illumination had to be picked.


  • Torsten Schmutzler
  • Gunnar Schröder

Software Architecture

UML Übersicht


  • Geometry: Torus, Cylinder, Tube
  • Different camera modells: perspective, orthogonal and fish-eye camera
  • Depth of field
  • Antialiasing: jittered supersampling
  • Edgedetection for speeding up supersampling
  • Soft Shadows
  • Efficiency: bounding volume hierarchies and shadow cache
  • Global illumination: photon mapping

Result Images

Die DuskShroud Szene Eine Büste

Rendering of the DuskShroud Szene(3721 Triangles) with Defaultsettings without Pruning
Vorbereitungszeit Renderzeit Summe
Flat List 00.04687 s 25 min 07.79687 s 25 min 07.84375 s
Bounding Volume Leaves 00.04687 s 4 min 24.85937 s 4 min 24.90625 s
BVH Quantative Longest 00.1602304 s 15.2118736 s 15.3721040 s
BVH Quantative Round Robin 00.0701008 s 13.4593536 s 13.5294544 s
BVH Spatial Longest 00.0901296 s 12.4779424 s 12.5680720 s
BVH Spatial Round Robin 00.1001440 s 12.6481872 s 12.7483312 s

Rendertimes (463949 Triangles) in 1024x768 without Pruning
Vorbereitungszeit Renderzeit Summe
BVH QL 38.26562 s 12.81250 s 51.07812 s
BVH QRR 24.78125 s 16.82812 s 41.60937 s
BVH SL 19.81250 s 12.21875 s 32.03125 s
BVH SRR 21.73437 s 13.31250 s 35.04687 s
BVH SL with Pruning 37.12500 s 11.39062 s 48.51562 s
BVH SL with Flatten 20.92187 s 12.35937 s 33.28125 s

A Spherefractal on the left. On the Right side our supported Primitives are shown. (The Torusknot is a trianglemesh). Additionally reflections, refractions, spotlight, arealight and photon mapping was used.

Fischaugenkamera Depth of Field
Features of the cameraimplementaion. Left: Fisheyecamera with 360 degree viewangle. Right: Depth of Field. The white ball is in focus.

Left: Cornell Box with reflective and refractive Matirials for causics.
Right: The classic Cornell Box.

Photon Mapping in action. Left: A cloisterszene with ambient lighting. Right: The same scene with global illumination.

Left: Caustic of a transparent teapot. Right: Chessszene with different procedural textures. (checker, wood and marble)
Last modified: 1st Feb 2010, 3.04 PM
Author: Dipl.-Inf. (FH) Benjamin Neidhold