mirror and whitted in dev

CMakeLists.txt

@@ -34,6 +34,7 @@ src/FunctionLayer/Texture/ImageTexture.cpp
 src/FunctionLayer/Texture/Texture.cpp
 src/FunctionLayer/Texture/Mipmap.cpp
 src/FunctionLayer/Material/Matte.cpp
+src/FunctionLayer/Material/Mirror.cpp
 src/FunctionLayer/Material/Material.cpp
 src/FunctionLayer/Sampler/IndependentSampler.cpp
 src/ResourceLayer/Image.cpp

examples/bunny/scene.json

@@ -1,6 +1,6 @@
 {
  "output" : {
- "filename" : "cornell-18.png"
+ "filename" : "bunny-1.hdr"
  },
  "sampler" : {
  "type" : "independent",
@@ -24,7 +24,7 @@
  }
  },
  "integrator" : {
- "type" : "directSampleLight"
+ "type" : "directSampleBSDF"
  },
  "scene" : {
  "shapes" : [
@@ -45,8 +45,7 @@
  "edge0" : [0, 0, 20],
  "edge1" : [20,0,0],
  "material" : {
- "type" : "matte",
- "albedo" : [0.8, 0.8, 0.8]
+ "type" : "mirror"
  }
  } 
  ],

src/FunctionLayer/Integrator/WhittedIntegrator.cpp

@@ -0,0 +1,45 @@
+#include "WhittedIntegrator.h"
+#include <FunctionLayer/Material/Material.h>
+
+Spectrum WhittedIntegrator::li(const Ray &_ray, const Scene &scene,
+ std::shared_ptr<Sampler> sampler) const {
+ Spectrum spectrum(.0f), beta(.0f);
+ Ray ray(_ray);
+
+ do {
+ auto itsOpt = scene.rayIntersect(ray);
+
+ // escape the scene
+ if (!itsOpt.has_value()) {
+ for (auto light : scene.infiniteLights) {
+ spectrum += light->evaluateEmission(ray);
+ }
+ break;
+ }
+
+ Intersection its = itsOpt.value();
+ computeRayDifferentials(&its, ray);
+ auto bsdf = its.shape->material->computeBSDF(its);
+
+ auto bsdfSampleResult = bsdf->sample(-ray.direction, sampler->next2D());
+
+ // If the surface is specular, spwan the ray
+ if (bsdfSampleResult.type == BSDFType::Specular) {
+ ray = Ray(its.position, bsdfSampleResult.wi);
+ beta *= bsdfSampleResult.weight;
+ continue;
+ }
+ // If the surface is not specular, sample the light
+ else {
+
+ // First, sample infinite light
+ for (auto light : scene.infiniteLights) {
+ auto lightSampleResult = light->sample(its, sampler->next2D());
+ Ray shadowRay(its.position, lightSampleResult.direction, 1e-4f,
+ FLT_MAX);
+ }
+ }
+ } while (1);
+
+ return spectrum;
+}

src/FunctionLayer/Integrator/WhittedIntegrator.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "Integrator.h"
+
+class WhittedIntegrator : public Integrator {
+public:
+ WhittedIntegrator() = default;
+
+ WhittedIntegrator(const Json &json) : Integrator(json) {}
+
+ virtual ~WhittedIntegrator() = default;
+
+ virtual Spectrum li(const Ray &ray, const Scene &scene,
+ std::shared_ptr<Sampler> sampler) const override;
+};

src/FunctionLayer/Material/BxDF/BSDF.h

@@ -1,10 +1,14 @@
 #pragma once
 #include <CoreLayer/ColorSpace/Spectrum.h>
 #include <FunctionLayer/Shape/Intersection.h>
+
+enum class BSDFType { Diffuse, Specular };
+
 struct BSDFSampleResult {
  Spectrum weight;
  Vector3f wi;
  float pdf;
+ BSDFType type;
 };
 
 class BSDF {

src/FunctionLayer/Material/BxDF/Lambert.h

@@ -19,7 +19,7 @@ class LambertReflection : public BSDF {
  Spectrum weight = albedo;
  Vector3f wi = squareToCosineHemisphere(sample);
  float pdf = squareToCosineHemispherePdf(wi);
- return {weight, toWorld(wi), pdf};
+ return {weight, toWorld(wi), pdf, BSDFType::Diffuse};
  }
 
 private:

src/FunctionLayer/Material/BxDF/Specular.h

@@ -13,9 +13,8 @@ class SpecularReflection : public BSDF {
 
  virtual BSDFSampleResult sample(const Vector3f &wo,
  const Vector2f &sample) const override {
- //
  Vector3f woLocal = toLocal(wo);
  Vector3f wiLocal{-woLocal[0], woLocal[1], -woLocal[2]};
- return {Spectrum(1.f), toWorld(wiLocal), 1.f};
+ return {Spectrum(1.f), toWorld(wiLocal), 1.f, BSDFType::Specular};
  }
 };

src/FunctionLayer/Material/Mirror.cpp

@@ -0,0 +1,13 @@
+#include "Mirror.h"
+#include "./BxDF/Specular.h"
+
+MirrorMaterial::MirrorMaterial(const Json &json) : Material(json) {}
+
+std::shared_ptr<BSDF>
+MirrorMaterial::computeBSDF(const Intersection &intersection) const {
+ Vector3f normal, tangent, bitangent;
+ computeShadingGeometry(intersection, &normal, &tangent, &bitangent);
+ return std::make_shared<SpecularReflection>(normal, tangent, bitangent);
+}
+
+REGISTER_CLASS(MirrorMaterial, "mirror")

src/FunctionLayer/Material/Mirror.h

@@ -0,0 +1,12 @@
+#pragma once
+#include "Material.h"
+
+class MirrorMaterial : public Material {
+public:
+ MirrorMaterial();
+
+ MirrorMaterial(const Json &json);
+
+ virtual std::shared_ptr<BSDF>
+ computeBSDF(const Intersection &intersection) const override;
+};