Parses and rasterize 3D object data from .obj files. Applies transformations and a lighting model to add lights and shadows to the scene.
OBJ format is a simple data-format that represents 3D geometry with triangles, using the position of each vertex, the UV position of each texture coordinate vertex, vertex normals and faces that make each polygon.
Built for Computer Graphics, at Comenius University of Bratislava.
The motivation of this project was learning how 3D modeled objects can be displayed in 2D scenes and the different techniques that helps us achieve that objective.
The instructor of this class encouraged us to do this project in Python. However, I was a bit reluctant about it because I am not much into it so for me it would be more complicated rather than easy.
As I love Rust and it is one of the programming languages that I want to really master, I considered doing this project with it, but creating graphical interfaces with it was going to be a really hard problem which I wasn't willing to cope with it in this project, as I had a deadline.
Finally, I decided to use Kotlin, as it was a language that I had been using for quite a bit given my Android development journey. In addition, runs in the JVM, so it is very similar to Java, my most used language. With Kotlin I was able to use Java AWT, a library that I could use to create graphic interfaces with ease.
The functionality of this project can be divided in various steps:
- Parse the obj file into the triangles that compose the object
- Apply transformations to each point (translation, scaling and rotation)
- Render each triangle of the object:
- Check if the triangle is not facing the camera (back-face culling)
- Calculate illumination model color (Blinn-Phong)
- Draw triangle with the calculated color