dipmizu914 / vk_pBRDF

Vulkan-based polarimetric BRDF (pBRDF) renderer by path tracing friendly to NVIDIA Vulkan Wrapper

Vulkan-based polarimetric BRDF (pBRDF) renderer by path tracing friendly to NVIDIA Vulkan Wrapper

Demo (Link to YouTube)

1. Explanation

This code is pBRDF renderer by path tracing on Vulkan API with NVIDIA Wrapper

2. Requirements on Windows

• Visual Studio 2019
• Vulkan SDK above version 1.2.162.0.
• NVIDIA graphics board that supports VK_KHR_ray_tracing_pipeline extension and corresponding drivers (latest recommended)
• CMake above version 3.9.6.

The code has not been tested on other platforms.

3. Setup

1. Clone this repository as follows,

git clone https://github.com/dipmizu914/vk_pBRDF.git --recurse-submodules

2. Build by using CMake.

4. Fix third-party code to read the index of refraction (ior)

1. Add transmission extension name to thirdparty/shared_sources/nvh/gltfscene.hpp as follows,

 // Line 68-
 #define KHR_LIGHTS_PUNCTUAL_EXTENSION_NAME "KHR_lights_punctual"
 #define KHR_TEXTURE_TRANSFORM_EXTENSION_NAME "KHR_texture_transform"
 #define KHR_MATERIALS_PBRSPECULARGLOSSINESS_EXTENSION_NAME "KHR_materials_pbrSpecularGlossiness"
 #define KHR_MATERIALS_UNLIT_EXTENSION_NAME "KHR_materials_unlit"
 #define KHR_MATERIALS_ANISOTROPY_EXTENSION_NAME "KHR_materials_anisotropy"
 #define KHR_MATERIALS_TRANSMISSION_NAME "KHR_materials_transmission"

2. Add ior property for material to thirdparty/shared_sources/nvh/gltfscene.hpp as follows,

 // Line 112- in struct GltfMaterial
  float anisotropy{0};
  vec3  anisotropyDirection{1, 0, 0};
  int   anisotropyTexture{-1};

  float ior{ 1.45 };
  }

3. Add ior reader to void GltfScene::importMaterials(const tinygltf::Model& tmodel) function in thirdparty/shared_sources/nvh/gltfscene.cpp as follows,

 // Line 112- in void GltfScene::importMaterials(const tinygltf::Model& tmodel)
      if (khr.Has("anisotropyTexture"))
      {
        gmat.anisotropyTexture = khr.Get("anisotropyTexture").Get("index").Get<int>();
      }
    }

    if (tmat.extensions.find(KHR_MATERIALS_TRANSMISSION_NAME) != tmat.extensions.end()) {
      const auto& khr = tmat.extensions.find(KHR_MATERIALS_TRANSMISSION_NAME)->second;
      if (khr.Has("ior"))
      {
        gmat.ior = static_cast<float>(khr.Get("ior").Get<double>());
      }
    }
    m_materials.emplace_back(gmat);
  }