Computer Graphics Project --- Ray Tracing

Requirements

GNU GCC C++ compiler 5.4 (at least support C11)
CMake 3.5+
OpenCV (optional)
GLFW3 - OpenGL (optional)

To compile correctly, at least one of OpenCV and OpenGL is needed for rendering, and you can specify the option in the CMakeLists.txt file.

Instruction

Clone the repository

git glone git@github.com:lw396285v/raytrace.git
cd raytrace

Check CMakeLists.txt, and set build option, for example if you only have OpenGL library installed, you can set:

set(BUILD_WITH_OPENGL 1) # which means you have OpenGL library
set(BUILD_WITH_OPENCV 0) # which means you don't have OpenCV library

Then you can run these commands in the source directory to build

mkdir build
cmake ..
make all -j8 
# on Windows it may be slightly different, after "cmake ..", you may need to use Visual Studio to open the project and build.

After building, you will find 4 executable files
```
tracer
tracer_double
tracer_single
UnitTest
```
To visualize the result, you can run each executable like
```
# command : [excutable name] [rendering method]
# for example
tracer_double opencv;
UnitTest opengl;
```
but remember, only OpenCV Rendering will save a PNG image snapshot under its root directory.

Result

Each executable will generate a scene, and they are shown here

UnitTest

This is a simple scene, which include 3 planes, 1 sphere and 1point light source. The rays are recursively traced 2 times. All objects' material use Phong reflection model. The differences are:

The shininess term is different. It is obvious that the sphere is more shiny.

The planes and the sphere have different mirror property (reflection).

The sphere has glass property (transparency).

tracer

This scene contains 2 sphere, 1 cylinder, 1 octahedron and 5 planes, with 1 point light source. The rays are recursively traced 3 times.

only the front sphere is transparent.

All objects except the left, back and right planes have mirror property.

Due to different ambient light terms and reflect behaviors (specular and diffuse term), the colors of the objects are different.

shininess terms are different

But with one point light source, the shadow is sharp.

tracer_single

Compare to tracer , tracer_single has a different light source. In face, 9 point light sources are used to simulate 1 circle light source. and we can find that the shadow become soft.

tracer_double

I add another circle light source (In fact, there are total 12 point light source) in the scene. Maybe it's too bright?

Code structure

Problems encountered