1 #include "brdf.h"

2 #include "erebus_impl.h"

3

4 // ---- class Reflectance ----

5 Reflectance::Reflectance()

6 {

7 }

8

9 float Reflectance::sample(const Vector3 &norm, const Vector3 &outdir, Vector3 *indir) const

10 {

11 *indir = sample_dir(norm, outdir);

12 return eval(norm, outdir, *indir);

13 }

14

15 // --- class LambertRefl ---

16 Vector3 LambertRefl::sample_dir(const Vector3 &norm, const Vector3 &outdir) const

17 {

18 Vector3 dir = Vector3{randf(-1, 1), randf(-1, 1), randf(-1, 1)}.normalized();

19 return dot_product(dir, norm) < 0.0 ? -dir : dir;

20 }

21

22 float LambertRefl::eval(const Vector3 &norm, const Vector3 &outdir, const Vector3 &indir) const

23 {

24 return dot_product(norm, outdir);

25 }