Soft Trace

CPU Ray Tracing application exhibiting basic Global Illumination effects. The application displays a Qt UI with two windows: the left window shows the scene rendered using OpenGL (immediate mode), while the right window displays the equivalent ray-traced scene.

The different effects are achieved by performing different ray generation + intersection + resolution strategies.

Global Illumination effects supported

• Blinn-Phong shading - Affected by standard .mtl properties {Ka, Kd, Ks, Ke}
• Fresnel - Controlled by custom .mtl property N_ior (see Typical values)
• Reflections - Controlled by custom .mtl property 0 <= N_mirr <= 1
• Refractions - Controlled by custom .mtl property 0 <= N_transp <= 1
• Shadows - Single shadow ray test
• Area Lights - 20 shadow samples
• Interpolation - Render normal as [r, g, b] = abs([n.x, n.y, n.z])
• Orthographic - Renders scene using Orthographic or Perspective camera

Project Structure

soft-trace/
├── src/                 # Source code
├── assets/              # Static assets (.obj and .mtl files)
├── soft-trace.pro       # QMake project
└── README.md            # Project README

Build

qmake
make

Run

bin/soft-trace <.obj> <.mtl>

Example:

bin/soft-trace assets/cornell_box.obj assets/cornell_box.mtl

The asset files must be well-formed for the application to work. See Material.h for custom .mtl properties used. Example files are provided.

Technologies

• C++: >= C++17
• Qt: 5.12.x
• OpenGL: >= 4.0
• OpenMP: >= 4.5
• GLM: 1.0.1

Newer versions of Qt might work correctly, if no breaking changes that affect the application were introduced.