From 127aa75e0f32446438c7ab83cf76c44bee42007d Mon Sep 17 00:00:00 2001
From: yumcyawiz <hashdolf1923@gmail.com>
Date: Mon, 22 Nov 2021 17:10:11 +0900
Subject: [PATCH] do not add LDS path in caustics photon map

---
 include/integrator.h | 9 +++++++--
 include/scene.h      | 4 +---
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/include/integrator.h b/include/integrator.h
index daae946..406463e 100644
--- a/include/integrator.h
+++ b/include/integrator.h
@@ -454,6 +454,13 @@ class PhotonMapping : public Integrator {
           IntersectInfo info;
           if (scene.intersect(ray, info)) {
             const BxDFType bxdf_type = info.hitPrimitive->getBxDFType();
+
+            // break when hitting diffuse surface without previous specular
+            if (!prev_specular && bxdf_type == BxDFType::DIFFUSE) {
+              break;
+            }
+
+            // add photon when hitting diffuse surface after specular
             if (prev_specular && bxdf_type == BxDFType::DIFFUSE &&
                 !info.hitPrimitive->hasAreaLight()) {
               // TODO: remove lock to get more speed
@@ -462,8 +469,6 @@ class PhotonMapping : public Integrator {
                 photons.emplace_back(throughput, info.surfaceInfo.position,
                                      -ray.direction);
               }
-
-              // break after the first diffuse surface
               break;
             }
 
diff --git a/include/scene.h b/include/scene.h
index eecc850..4a8b40e 100644
--- a/include/scene.h
+++ b/include/scene.h
@@ -26,9 +26,6 @@ const std::shared_ptr<BxDF> createBxDF(const tinyobj::material_t& material) {
       Vec3f(material.specular[0], material.specular[1], material.specular[2]);
 
   switch (material.illum) {
-    case 2:
-      // lambert
-      return std::make_shared<Lambert>(kd);
     case 5:
       // mirror
       return std::make_shared<Mirror>(Vec3(1.0f));
@@ -36,6 +33,7 @@ const std::shared_ptr<BxDF> createBxDF(const tinyobj::material_t& material) {
       // glass
       return std::make_shared<Glass>(Vec3(1.0f), material.ior);
     default:
+      // lambert
       return std::make_shared<Lambert>(kd);
   }
 }