miniRT

This project introduces the following topics:

• Intermediate raytracing protocol implementation (visibility part)
• Image saving in a non-compressed format (BMP)
• Deep error management
• Basic raytracing protocol implementation (shading part, by using Lambert law and other light properties)

Before explaining how the project works, how to compile and run it

On MacOS outside the 42 Network

You will have to make some changes to make sure MiniLibX can be properly used.
The way I recommend installing it is by compiling MiniLibX from sources (which can be found on intra project page, or by using this instance minilibx)
and copying mlx.h into /usr/local/include/mlx.h and libmlx.a to /usr/local/lib/libmlx.a

Then proceed the same way as if you were on a 42 iMac

On 42 Network campus iMacs

To make it work on 42 iMacs, you need to clone somewhere (to make it easier, under srcs/ is a good option) both libft and get_next_line as they are required dependencies.

The following step is to compile it, you can do it with a simple make, or if you cloned the dependencies somewhere that is not under srcs, using make MINIRT_LIBFT=../relative/path/to/libft MINIRT_GNL=/absolute/paths/work/too will do the job.

An output file called miniRT will be produced (otherwise message me, mmartin- on Slack).

How to run miniRT

Program usage is ./miniRT <rt_file> [--save]. If --save is not specified,
a window will open with the rendered content of the file. If --save is specified,
a screenshot.bmp image will be generated.

The structure of a .rt file is as follow:
| Parameter | Arguments | Usage example |
|———————————————-|————————————————————————————————————————————————————|——————————————————-|
| R | X[width of window] Y[height of window] | R 1920 1080 |
| A | R[ratio of ambient light] C[color of ambient light] | A 0.01 127,255,0 |
| c | O[x,y,z coordinates] D[x,y,z normalized direction] F[field of view] | C 0,0,-40 0,0,1 80 |
| l | O[x,y,z coordinates] R[ratio of light] C[color of light] | l 0,100,0 1.0 255,0,0 |
| sp | O[x,y,z coordinates] D[diameter of sphere] C[color of sphere] | sp 0,40,0 19 255,255,255 |
| pl | O[x,y,z coordinates] D[x,y,z normalized direction] C[color of plane] | pl 0,15,0 0,1,0 255,0,0 |
| sq | O[x,y,z coordinates] D[x,y,z normalized direction] C[color of square] | sq 0,0,0 0,0,1 255,0,255 |
| cy | O[x,y,z coordinates] D[x,y,z normalized direction] D[diameter of cyl] H[height of cyl] C[color of cyl] | cy 0,0,0 0,1,1 8 30 255,0,0 |
| tr | A[x,y,z vertex 1] B[x,y,z vertex 2] C[x,y,z vertex3] C[color of triangle] | tr 0,20,10 15,-4,-10 12,0,0 255,0,0 |

How the project work

First of all, I had to learn maths from scratch. At the start of the project I didn’t know nor understand any of linear algebra or trigonometry.
For this matter, I used 3blue1brown Linear Algebra resources.

Talking about resources, the list for everything I’ve used to learn about this topic (and even rasterization and similar topics):

• Essence of linear algebra, by 3blue1brown
• Geometry, by Scratchapixel
• Fast, Minimum Storage Ray/Triangle Intersection, by Tomas Möller and Ben Trumbore 1997
• Geometric equation for sphere and plane, By Scratchapixel
• Ray-cylinder intersection, by Denis Zorin 1999

The project consists of four parts:

• Argument validation and file reading and validation
• Visibility part by ray-geometry intersection
• Shading part, using Lambert law and intersection between objects
• Saving image to BMP or displaying it to window

Score

This project took me too long because of the mathematic base I had to adquire. It will be greatly improved over time, but as I cannot submit it
again it will remain with 100/100 (with bonus it would be 100/115).