blob: 66ea25641d92fb53373970da2c63aa045e3f7d83 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
package main
//Material
type Material interface {
Attenuation() Vec3
Scatter(r Ray, hit HitRecord) Ray
}
//Lambertian
type Lambertian struct {
Albedo Vec3
}
func (l Lambertian) Attenuation() Vec3 {
return l.Albedo;
}
func (l Lambertian) Scatter(r Ray, hit HitRecord) Ray {
scat_dir := hit.N.Add(RandomVec3OnUnitSphere());
if scat_dir.NearZero() {
scat_dir = hit.N;
}
return Ray{hit.P, scat_dir, true};
}
//Metal
type Metal struct {
Albedo Vec3
Fuzz float64
}
func (m Metal) Attenuation() Vec3 {
return m.Albedo;
}
func (m Metal) Scatter(r Ray, hit HitRecord) Ray {
refl := r.Direction.Reflect(hit.N).Unit().
Add(SplatVec3(m.Fuzz).Mul(RandomVec3OnUnitSphere()));
valid := refl.Dot(hit.N) > 0;
return Ray{hit.P, refl, valid};
}
|
