Added Heidrich-Seidel anisotropic BRDF.

hsa_brdf.hpp

@@ -0,0 +1,21 @@
+#pragma once
+#ifndef HSA_BRDF_HPP
+#define HSA_BRDF_HPP
+
+#include "phong_brdf.hpp"
+
+using glm::normalize;
+
+class HeidrichSeidelAnisotropicBRDF: public PhongBRDF {
+public:
+  vec3 thread_dir;
+
+  HeidrichSeidelAnisotropicBRDF(vec3 _d): PhongBRDF(), thread_dir(normalize(_d)) { }
+
+  virtual ~HeidrichSeidelAnisotropicBRDF() { }
+  
+  virtual vec3 diffuse(vec3 light_dir, vec3 surface_normal, Ray & incident_ray, vec3 intersection_point, vec3 light_diff_color) const;
+  virtual vec3 specular(vec3 light_dir, vec3 surface_normal, Ray & incident_ray, vec3 intersection_point, vec3 light_spec_color, float shininess) const;
+};
+
+#endif