adding brdf, but virtual is probably terrible for performance

src/util/BRDF.cpp

@@ -0,0 +1,11 @@
+#include "BRDF.h"
+
+glm::vec3 BlinnPhong::evaluate(HitInfo hit, glm::vec3 viewDir, glm::vec3 lightDir, glm::vec3 lightColor)
+{
+  glm::vec3 normal = hit.normal;
+  float diffuse = std::max(glm::dot(normal, lightDir), 0.0f);
+  glm::vec3 h = glm::normalize(lightDir + viewDir);
+  float specular = pow(std::min(std::max(glm::dot(normal, h), 0.0f), 1.0f), shininess);
+
+  return (albedo * diffuse * lightColor) + (specularColor * specular);
+}

src/util/BRDF.h

@@ -0,0 +1,17 @@
+#pragma once
+#include "Material.h"
+
+class BRDF
+{
+  virtual glm::vec3 evaluate(HitInfo hit, glm::vec3 viewDir, glm::vec3 lightDir, glm::vec3 lightColor) = 0;
+};
+
+class BlinnPhong : public BRDF
+{
+  glm::vec3 albedo = glm::vec3(1, 1, 1);
+  float alpha = 1;
+  glm::vec3 specularColor = glm::vec3(1, 1, 1);
+  float shininess = 0;
+  glm::vec3 emissive = glm::vec3(0, 0, 0);
+  virtual glm::vec3 evaluate(HitInfo hit, glm::vec3 viewDir, glm::vec3 lightDir, glm::vec3 lightColor);
+};

src/util/CMakeLists.txt

@@ -1,5 +1,7 @@
 target_sources(RayTracer
 	PRIVATE
+		BRDF.h
+		BRDF.cpp
 		Camera.h
 		Material.h
 		Material.cpp

src/util/Material.cpp

@@ -1 +1,6 @@
-#include "Material.h"
+#include "Material.h"
+
+std::unique_ptr<BRDF> Material::evaluate(HitInfo hitInfo)
+{
+  return std::make_unique<BlinnPhong>();
+}

src/util/Material.h

@@ -1,7 +1,20 @@
 #pragma once
+#include "Minimal.h"
+#include "Texture.h"
+#include "Ray.h"
+#include "BRDF.h"
+
+enum class MaterialType
+{
+	DIFFUSE,
+	SPECULAR,
+	REFRACTIVE,
+};
 
 class Material
 {
 public:
-private:
+  std::unique_ptr<BRDF> evaluate(HitInfo hitInfo);
+  PTexture albedoTexture;
+  PTexture emissiveTexture;
 };

src/util/Model.h

@@ -1,20 +1,14 @@
 #pragma once
 #include "Minimal.h"
+#include "Material.h"
 #include "scene/AABB.h"
 #include <optional>
 #include <vector>
 
-// material infos
-// shading parameter
-// hit data
 struct IntersectionInfo
 {
-  float t;
-  glm::vec3 position;
-  glm::vec3 normal;
-  glm::vec3 albedo;
-  glm::vec3 emissive;
-  //....
+  HitInfo hitInfo;
+  MaterialInfo shadingInfo;
 };
 class Model
 {

src/util/Ray.h

@@ -1,8 +1,24 @@
 #pragma once
 #include <glm/glm.hpp>
 
+struct Payload
+{
+  glm::vec3 accumulatedRadiance = glm::vec3(0);
+  glm::vec3 accumulatedMaterial = glm::vec3(0);
+};
+
 struct Ray
 {
     glm::vec3 origin;
     glm::vec3 direction;
+    uint32_t depth = 0;
+    Payload payload;
+};
+
+struct HitInfo
+{
+  float t;
+  glm::vec3 position;
+  glm::vec3 normal;
+  glm::vec2 texCoords;
 };