ray-tracer

Simple ray tracer written in C++

Building

git clone https://github.com/giorgianb/ray-tracer
cd ray-tracer
./compile.sh

Usage

To use the ray tracer, the light sources and the objects in the world need to be specified. These are stored in a text file. There are various objects that can be traced.

Colors

Colors are specified using an r g b value which respectively specify the red, green, and blue values of the object. They must all be between 0 and 1.

Spheres

Spheres can be specified in the following manner:

Sphere
x y z radius r g b

Here, x y z are the coordinates of the center of the sphere, and radius is the radius of the sphere.

Planes

Planes can be specified in the following manner:

Plane
ux uy uz vx vy vz ox oy oz r g b

Here, a plane is specified in the form of s(ux, uy, uz) + t(vx, vy, vz) + (ox, oy, oz), where (ox, oy, oz) specify an offset and (ux, uy, uz) and (vx, vy, vz) are the direction vectors of the plane. In general, if you have the points P, Q, and R specifying a plane, (ux, uy, uz) can be defined as PQ (the vector from point P to point Q), (vx, vy, vz) can be defined as PR (the vector from point P to R), and (ox, oy, oz) can be specified as R.

Polygons

Polygons can be specified in the following manner:

Polygon
ux uy uz vx vy vz ox oy oz
number_vertices
v1_x v1_y v1_z
v2_x v2_y v2_z
v3_x v3_y v3_z
...
vn_x vn_y vn_z
r g b

The first part specifies the plane that the polygon has on. It is specified in the same manner as mentioned above, in the Plane section: where the plane is specified in the form s(ux, uy, uz) + t(vx, vy, vz) + (ox, oy, oz). Then, the number of vertices of the polygon is specified. Important: This will always be one more than the actual number of vertices of the Polygon. For example, if the you want to specify a triangle, the number of vertices will be 4. This is because the first and last vertex must be the same. Then, after the number of vertices is specified, the vertices are listed in a counterclockwise manner.

Checkered Planes

Checkered Planes can be specified in the following manner:

CheckeredPlane
ux uy uz vx vy vz ox oy oz
number_colors
r1 g1 b1
r2 g2 b2
r3 g3 b3
rn gn bn

The checkered plane is specified in the same manner as mentioned in the Plane section: where the plane is specified in the form s(ux, uy, uz) + t(vx, vy, vz) + (ox, oy, oz). Then, the number of colors is specified. What follows are the r, g, and b value of the colors. The size and shape of the "checker" is defined by the parallogram spanned by the vectors (ux, uy, uz) and (vx, vy, vz).

Point Light Sources

Point light sources are specified in the following manner:

PointLightSouce
x y z brightness

Here, (x, y, z) specify the location of the point light source. brightness specifies the brightness of the source. A good value is normally 2000000 although this highly depends on the distance of the light source from everything else.

Sample Usage

magenta-sphere.rt:

Sphere
0 0 500	50 	1 0 1
PointLightSource
500 200 0 300000
PointLightSource
-500 -200 0 50000

./rt --file=magenta-sphere.rt --out=magenta-sphere.ppm