Rend-a-Pixel (Raytracer)

Rend-a-Pixel is a raytracing rendering engine developed on top of the Lightwave Framework as the final project for the Computer Graphics course at Saarland University lectured by Prof. Dr.-Ing. Philipp Slusallek during the Winter Semester 2023/2024. Some of the implemented features are showcased below:

Area Lights

No Area Lights	Uniform Sphere Sampling
Cosine-Weighted Sampling	Subtended-Cone Sampling

Multiple Importance Sampling

BSDF Sampling	NEE	MIS

Shading Normals

No Normal Mapping	Normal Mapping

A Thinlens Camera Model

Perspective	With Thinlens

Alpha Masking

Without Alpha Masking	With Alpha Masking

Custom Bokeh Shapes

Sphere-looking Lights	3-bladed Bokeh Shapes

Image Denoising

Noisy	Denoised

Halton Sampler

Independent Sampling	Normal Halton Sampling
Digit-permutated Halton Sampling	Owen-scrambled Halton Sampling

Halton Sampler (In detail)

Independent Sampling	Normal Halton Sampling
Digit-permutated Halton Sampling	Owen-scrambled Halton Sampling

Summary of Features

• Camera Models
  • Basic Perspective Camera
  • Thinlens Camera
• Basic Primitives
  • Sphere
  • Rectangles
  • Triangle/Generic Meshes
• Integrators
  • Albedo
  • Normals
  • Direct Lighting
  • Path Tracing
• BSDFs & Lighting Models:
  • Materials:
    • Diffuse
    • Conductor
    • Rough Conductor
    • Dielectric
    • Principled
  • Lambertian Emission
• Textures:
  • Checkerboard Texture
  • Image Texture
• Lights:
  • Environment Map
    • Improved Environment Sampling
  • Area Lights
    • Uniform Sphere Sampling
    • Cosine-Weighted Sampling
    • Subtended-Cone Sampling
  • Point Light
  • Directional Light
• Sampling:
  • BSDF Sampling
  • Next Event Estimation (NEE)
  • Multiple Importance Sampling (MIS)
• Image denoising using Intel® Open Image Denoise
• Acceleration Structures:
  • SAH Bounding Volume Hierarchy
• Shading Normals
• Alpha Masking
• Custom Bokeh Shapes

Copyright & Credits

© The Lightwave Framework was written by Alexander Rath, with contributions from Ömercan Yazici and Philippe Weier. Their support was invaluable in the coding of these features. The scenes showcasing the features were provided by their team, and should be used under permission. Many textures and models were taken from Poly Haven's extensive library. Many thanks to the team behind Tev used extensively throughout this project as an EXR viewer.

References

1. Tomas Akenine-Mller, Eric Haines, and Naty Hoffman. Real-Time Rendering (4th ed.) USA: A. K. Peters, Ltd., 2018. ISBN: 0134997832.
2. John F. Hughes et al. Computer Graphics - Principles and Practice, (3rd ed.) Addison-Wesley, 2014. ISBN: 978-0-321-39952-6.
3. Matt Pharr, Wenzel Jakob, and Greg Humphreys. Physically Based Rendering: From Theory to Implementation, (3rd ed.) Morgan Kaufmann Publishers Inc., 2016, ISBN: 978-0128006450.
4. Matt Pharr, Wenzel Jakob, and Greg Humphreys. Physically Based Rendering: From Theory to Implementation, (4th ed.) MIT Press, 2023, ISBN: 978-0262048026.