From: Patrick <patrick.schoenberger@posteo.de>
Date: Tue, 23 Mar 2021 18:28:28 +0000 (+0100)
Subject: fix translucency, add gaussian blur to shader
X-Git-Url: https://gitweb.ps.run/subsurface_scattering/commitdiff_plain/a0fdc6d882a1755d0b0607ba3d9bb55e7f8ac006?ds=inline

fix translucency, add gaussian blur to shader
---

diff --git a/build.sh b/build.sh
index a065433..8d878f5 100644
--- a/build.sh
+++ b/build.sh
@@ -1,2 +1,4 @@
-# g++ -c ~/cpp/libs/imgui/*.cpp ~/cpp/libs/imgui-sfml/*.cpp -I ~/cpp/libs/imgui -I ~/cpp/libs/imgui-sfml/
-g++ src/main.cpp ./*.o -o main -I ~/cpp/libs/imgui -I ~/cpp/libs/imgui-sfml -lsfml-system -lsfml-window -lsfml-graphics -lGLEW -lGL -lassimp
+#!/bin/sh
+
+# g++ -c C:/prg/cpp/libs/imgui/*.cpp C:/prg/cpp/libs/imgui-sfml/*.cpp -I C:/prg/cpp/libs/imgui -I C:/prg/cpp/libs/imgui-sfml -I C:/prg/cpp/libs/SFML-2.5.1/include
+g++ src/main.cpp ./bin/*.o -o main -I C:/prg/cpp/libs/SFML-2.5.1/include -I C:/prg/cpp/libs/assimp-5.0.1/include -I C:/prg/cpp/libs/assimp-5.0.1/build/include -I C:/prg/cpp/libs/glew-2.1.0/include -I C:/prg/cpp/libs/glm -I C:/prg/cpp/libs/imgui -I C:/prg/cpp/libs/imgui-sfml -L "C:/prg/cpp/libs/SFML-2.5.1/build/lib/Release" -L "C:/prg/cpp/libs/assimp-5.0.1/build/code/Release" -L "C:/prg/cpp/libs/glew-2.1.0/lib/Release/x64" -lsfml-system -lsfml-window -lsfml-graphics -lGLEW -lGL -lassimp
diff --git a/shaders/fbo_frag.glsl b/shaders/fbo_frag.glsl
index 7463fc8..1102992 100644
--- a/shaders/fbo_frag.glsl
+++ b/shaders/fbo_frag.glsl
@@ -11,24 +11,51 @@ uniform int renderState;
 uniform vec2 samplePositions[13];
 uniform vec3 sampleWeights[13];
 
+vec4 blur(sampler2D tex, vec2 uv, vec2 res) {
+  float Pi = 6.28318530718; // Pi*2
+    
+  // GAUSSIAN BLUR SETTINGS {{{
+  float Directions = 16.0; // BLUR DIRECTIONS (Default 16.0 - More is better but slower)
+  float Quality = 4.0; // BLUR QUALITY (Default 4.0 - More is better but slower)
+  float Size = 8.0; // BLUR SIZE (Radius)
+  // GAUSSIAN BLUR SETTINGS }}}
+  
+  vec2 Radius = Size/res;
+  
+  // Pixel colour
+  vec4 Color = texture(tex, uv);
+  
+  // Blur calculations
+  for( float d=0.0; d<Pi; d+=Pi/Directions) {
+    for(float i=1.0/Quality; i<=1.0; i+=1.0/Quality) {
+      Color += texture( tex, uv+vec2(cos(d),sin(d))*Radius*i);		
+    }
+  }
+  
+  // Output to screen
+  Color /= Quality * Directions - 15.0;
+  return Color;
+}
+
 void main()
 {
     if (renderState == 0) {
-        FragColor = texture(shadowmapTexture, TexCoords);
+        FragColor = blur(shadowmapTexture, TexCoords, vec2(screenWidth, screenHeight));
     }
-    // stencil buffer
     else if (renderState == 1) {
-        FragColor = texture(irradianceTexture, TexCoords);
+        FragColor = texture(shadowmapTexture, TexCoords);
     }
+    // stencil buffer
     else if (renderState == 2) {
-        FragColor = texture(shadowmapTexture, TexCoords) * texture(irradianceTexture, TexCoords);
+        FragColor = texture(irradianceTexture, TexCoords);
     }
     else if (renderState == 3) {
         vec4 result = vec4(0, 0, 0, 1);
         for (int i = 0; i < 13; i++) {
             vec2 sampleCoords = TexCoords + samplePositions[i] * vec2(1.0/screenWidth, 1.0/screenHeight);
-            vec4 sample = texture(irradianceTexture, sampleCoords)
-                        * texture(shadowmapTexture, sampleCoords);
+            //vec4 sample = texture(irradianceTexture, sampleCoords)
+            //            * texture(shadowmapTexture, sampleCoords);
+            vec4 sample = texture(irradianceTexture, sampleCoords);
             vec4 weight = vec4(sampleWeights[i], 1);
             result += sample * weight;
         }
diff --git a/shaders/frag_irradiance.glsl b/shaders/frag_irradiance.glsl
index 9e14ebe..497bdf0 100644
--- a/shaders/frag_irradiance.glsl
+++ b/shaders/frag_irradiance.glsl
@@ -1,16 +1,21 @@
 #version 330 core
 
 in vec3 FragPos;
+in vec3 LocalPos;
+in vec3 Backside;
+in float BacksideIrradiance;
 in vec3 Normal;
 
 out vec4 FragColor;
 
-uniform sampler2D shadowmapTexture;
-
 uniform vec3 objectColor;
 uniform vec3 lightColor;
 uniform vec3 lightPos;
 uniform vec3 viewPos;
+uniform float transmittanceScale;
+uniform int renderState;
+uniform float powBase;
+uniform float powFactor;
 
 void main()
 {
@@ -29,6 +34,22 @@ void main()
   float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);
   vec3 specular = specularStrength * spec * lightColor;
 
+  //float distanceToBackside = length(clamp(FragPos - Backside, vec3(0), vec3(1000)));
+  float distanceToBackside = length(FragPos - Backside);
+  //distanceToBackside = distance(Backside, LocalPos);
   vec3 result = (ambient + diffuse + specular) * objectColor;
+
+  if (renderState == 3)
+    if (distanceToBackside != 0)
+      //result += objectColor * pow(powBase, -pow(distanceToBackside, 2)) * transmittanceScale * (1 - diff);
+      result += objectColor * pow(powBase, powFactor / pow(distanceToBackside, 0.6)) * transmittanceScale * (1 - diff);
+  // if (renderState == 3) {
+  //   //result = Backside;
+  //   //result = LocalPos;
+  //   result = vec3(distanceToBackside);
+  // }
+
+    
   FragColor = vec4(result, 1.0f);
+  //FragColor = vec4(vec3(distanceToBackside), 1);
 }
diff --git a/shaders/frag_shadowmap.glsl b/shaders/frag_shadowmap.glsl
index 6d6dab6..9a15c7a 100644
--- a/shaders/frag_shadowmap.glsl
+++ b/shaders/frag_shadowmap.glsl
@@ -2,6 +2,7 @@
 #version 330 core
 
 in vec3 FragPos;
+in vec3 LocalPos;
 
 out vec4 FragColor;
 
@@ -9,6 +10,10 @@ uniform vec3 lightPos;
 
 void main()
 {
-  float lightDist = 1 - (length(lightPos - FragPos) - 5.5);
-  FragColor = vec4(vec3(lightDist), 1);
+  float lightDist = length(lightPos - FragPos);
+  float c1 = mod(lightDist, 10);
+  float c2 = mod(lightDist/10, 10);
+  float c3 = mod(lightDist/100, 10);
+  FragColor = vec4(c1, c2, c3, 1);
+  //FragColor = vec4(LocalPos/10, 1);
 }
diff --git a/shaders/vert_irradiance.glsl b/shaders/vert_irradiance.glsl
new file mode 100644
index 0000000..25770f6
--- /dev/null
+++ b/shaders/vert_irradiance.glsl
@@ -0,0 +1,77 @@
+#version 330 core
+
+layout (location = 0) in vec3 pos;
+layout (location = 1) in vec3 normal;
+
+out vec3 FragPos;
+out vec3 LocalPos;
+out vec3 Backside;
+out float BacksideIrradiance;
+out vec3 Normal;
+
+uniform sampler2D shadowmapTexture;
+uniform vec3 lightPos;
+uniform vec2 samplePositions[13];
+uniform vec3 sampleWeights[13];
+uniform int screenWidth;
+uniform int screenHeight;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 lightView;
+uniform mat4 lightViewInv;
+uniform mat4 projection;
+uniform mat4 lightProjection;
+
+vec4 blur(sampler2D tex, vec2 uv, vec2 res) {
+  float Pi = 6.28318530718; // Pi*2
+    
+  // GAUSSIAN BLUR SETTINGS {{{
+  float Directions = 16.0; // BLUR DIRECTIONS (Default 16.0 - More is better but slower)
+  float Quality = 4.0; // BLUR QUALITY (Default 4.0 - More is better but slower)
+  float Size = 8.0; // BLUR SIZE (Radius)
+  // GAUSSIAN BLUR SETTINGS }}}
+  
+  vec2 Radius = Size/res;
+  
+  // Pixel colour
+  vec4 Color = texture(tex, uv);
+  
+  // Blur calculations
+  for( float d=0.0; d<Pi; d+=Pi/Directions) {
+    for(float i=1.0/Quality; i<=1.0; i+=1.0/Quality) {
+      Color += texture( tex, uv+vec2(cos(d),sin(d))*Radius*i);		
+    }
+  }
+  
+  // Output to screen
+  Color /= Quality * Directions - 15.0;
+  return Color;
+}
+
+void main()
+{
+  gl_Position = projection * view * model * vec4(pos, 1.0);
+  FragPos = vec3(model * vec4(pos, 1));
+  LocalPos = pos;
+  Normal = normal;
+  
+  vec4 lightSpace = lightProjection * lightView * model * vec4(pos, 1.0);
+  lightSpace = lightSpace / lightSpace.w;
+  vec2 shadowmapCoords = lightSpace.xy;
+  shadowmapCoords = vec2(
+    (shadowmapCoords.x * 0.99 + 1) / 2,
+    (shadowmapCoords.y * 0.99 + 1) / 2
+  );
+
+
+  // blur
+  vec4 t = texture(shadowmapTexture, shadowmapCoords);
+  //vec4 t = blur(shadowmapTexture, shadowmapCoords, vec2(screenWidth, screenHeight));
+
+  BacksideIrradiance = t.r + t.g*10 + t.b*100;
+  
+  vec3 lightDir = (vec3(0, 0, 0) - lightPos);
+  Backside = (lightPos + (lightDir * BacksideIrradiance));
+  //Backside = texture(shadowmapTexture, shadowmapCoords).xyz*10;
+}
diff --git a/shaders/vert.glsl b/shaders/vert_shadowmap.glsl
similarity index 63%
rename from shaders/vert.glsl
rename to shaders/vert_shadowmap.glsl
index 6f48573..50847bb 100644
--- a/shaders/vert.glsl
+++ b/shaders/vert_shadowmap.glsl
@@ -4,15 +4,17 @@ layout (location = 0) in vec3 pos;
 layout (location = 1) in vec3 normal;
 
 out vec3 FragPos;
+out vec3 LocalPos;
 out vec3 Normal;
 
 uniform mat4 model;
-uniform mat4 view;
+uniform mat4 lightView;
 uniform mat4 projection;
 
 void main()
 {
-  gl_Position = projection * view * model * vec4(pos, 1.0);
+  gl_Position = projection * lightView * model * vec4(pos, 1.0);
   FragPos = vec3(model * vec4(pos, 1));
+  LocalPos = pos;
   Normal = normal;
 }
diff --git a/src/main.cpp b/src/main.cpp
index dde29ec..24a39cc 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -23,8 +23,13 @@
 /*
 
 TODO:
-- ShadowMap to fbo
 - Save Depth to fbo
+- Stencil Buffer
+- LightDist > 1
+  - 1 - distanceToBackside in frag_irradiance
+- ShadowMap Perspective (no projection?)
+- (Implement Gaussian Blur)
+- LightDir nicht immer zu 0 0 0
 
 */
 
@@ -101,7 +106,6 @@ private:
   GLuint VAO = 0;
 };
 
-
 struct freecam {
   glm::vec3 pos = glm::vec3(0, 0, -1);
   glm::vec2 rot = glm::vec2(0, 0);
@@ -155,7 +159,6 @@ private:
   float moveFactor = 20;
 };
 
-
 struct arccam {
   glm::vec2 rot = glm::vec2(0, 0);
   float radius = 1;
@@ -207,7 +210,6 @@ private:
   const float angleFactor = 200;
 };
 
-
 std::string readFile(std::string filename) {
   std::ifstream ifs(filename, std::ios::binary);
   std::string result, line;
@@ -222,19 +224,22 @@ model loadModel(const std::string &filename) {
 
   const aiScene *scene = importer.ReadFile(
       filename, aiProcess_CalcTangentSpace | aiProcess_Triangulate |
-                    aiProcess_SortByPType | aiProcess_GenSmoothNormals);
+                    aiProcess_SortByPType | aiProcess_GenSmoothNormals |
+                    aiProcess_GenUVCoords);
 
   model result;
 
+  printf("uv channels: %d\n", scene->mMeshes[0]->GetNumUVChannels());
+
   for (int i = 0; i < scene->mMeshes[0]->mNumVertices; i++) {
     aiVector3D v = scene->mMeshes[0]->mVertices[i];
     aiVector3D n = scene->mMeshes[0]->mNormals[i];
-    result.vertices.push_back(v.x);
-    result.vertices.push_back(v.y);
-    result.vertices.push_back(v.z);
-    result.vertices.push_back(n.x);
-    result.vertices.push_back(n.y);
-    result.vertices.push_back(n.z);
+    result.vertices.push_back(v.x * 100);
+    result.vertices.push_back(v.y * 100);
+    result.vertices.push_back(v.z * 100);
+    result.vertices.push_back(n.x * 100);
+    result.vertices.push_back(n.y * 100);
+    result.vertices.push_back(n.z * 100);
   }
 
   for (int i = 0; i < scene->mMeshes[0]->mNumFaces; i++) {
@@ -293,7 +298,6 @@ GLuint compileShaders(const char *vertFilename, const char *fragFilename) {
   return shaderProgram;
 }
 
-
 struct framebuffer {
   framebuffer(const char *vertFilename, const char *fragFilename, int width, int height) {
     glGenFramebuffers(1, &fbo);
@@ -387,23 +391,23 @@ int main() {
   if (glewInit() != GLEW_OK) {
   }
 
-  GLuint shaderProgramShadowmap = compileShaders("shaders/vert.glsl", "shaders/frag_shadowmap.glsl");
-  GLuint shaderProgramIrradiance = compileShaders("shaders/vert.glsl", "shaders/frag_irradiance.glsl");
+  GLuint shaderProgramShadowmap = compileShaders("shaders/vert_shadowmap.glsl", "shaders/frag_shadowmap.glsl");
+  GLuint shaderProgramIrradiance = compileShaders("shaders/vert_irradiance.glsl", "shaders/frag_irradiance.glsl");
 
-  model m = loadModel("models/Isotrop-upperjaw.ply");
+  //model m = loadModel("models/Isotrop-upperjaw.ply");
+  model m = loadModel("models/african_head/african_head.obj");
 
   arccam arcCam;
   freecam freeCam;
-      
-  glm::vec3 lightPos(1.2f, 5.0f, 2.0f);
 
   // MVP
 
   glm::mat4 model = glm::scale(glm::mat4(1.0f), glm::vec3(0.01f, 0.01f, 0.01f));
 
-  glm::mat4 view;
+  glm::mat4 view, lightView;
 
   glm::mat4 proj = glm::perspective(glm::radians(45.0f), (float)window.getSize().x / window.getSize().y, 0.001f, 1000.0f);
+  glm::mat4 lightProj = glm::perspective(glm::radians(90.0f), (float)window.getSize().x / window.getSize().y, 0.001f, 1000.0f);
 
   // Framebuffer
   framebuffer fb_shadowmap("shaders/fbo_vert.glsl", "shaders/fbo_frag.glsl", width, height);
@@ -411,12 +415,18 @@ int main() {
 
   // Config
 
-  struct {
+  const struct {
     bool wireframe = false;
     bool freecam = false;
-    int renderState = 0;
+    int renderState = 2;
     float color[3] = { 0.7f, 0.4f, 0.4f };
-  } options;
+    glm::vec3 lightPos = glm::vec3(0.0f, 0.04f, -0.08f);
+    float transmittanceScale = 0.005f;
+    float powBase = 2.718;
+    float powFactor = 1;
+  } DefaultOptions;
+
+  auto options = DefaultOptions;
 
   sf::Clock deltaClock;
 
@@ -473,6 +483,10 @@ int main() {
 
     // Render Shadowmap
 
+    glClampColor(GL_CLAMP_READ_COLOR, GL_FALSE);
+    glClampColor(GL_CLAMP_VERTEX_COLOR, GL_FALSE);
+    glClampColor(GL_CLAMP_FRAGMENT_COLOR, GL_FALSE);
+
     glBindFramebuffer(GL_FRAMEBUFFER, fb_shadowmap.fbo);
     glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
@@ -490,19 +504,21 @@ int main() {
     else
       view = arcCam.getViewMatrix();
     
+    lightView = glm::lookAt(options.lightPos, glm::vec3(0, 0, 0), glm::vec3(0, 1, 0));
+    
     glUniformMatrix4fv(
       glGetUniformLocation(shaderProgramShadowmap, "model"),
       1, GL_FALSE, glm::value_ptr(model));
     glUniformMatrix4fv(
-      glGetUniformLocation(shaderProgramShadowmap, "view"),
-      1, GL_FALSE, glm::value_ptr(view));
+      glGetUniformLocation(shaderProgramShadowmap, "lightView"),
+      1, GL_FALSE, glm::value_ptr(lightView));
     glUniformMatrix4fv(
       glGetUniformLocation(shaderProgramShadowmap, "projection"),
-      1, GL_FALSE, glm::value_ptr(proj));
+      1, GL_FALSE, glm::value_ptr(lightProj));
 
     glUniform3fv(
       glGetUniformLocation(shaderProgramShadowmap, "lightPos"),
-      1, glm::value_ptr(lightPos));
+      1, glm::value_ptr(options.lightPos));
 
     m.draw();
 
@@ -520,20 +536,41 @@ int main() {
 
     glUseProgram(shaderProgramIrradiance);
     
-    if (options.freecam)
-      view = freeCam.getViewMatrix();
-    else
-      view = arcCam.getViewMatrix();
-    
     glUniformMatrix4fv(
       glGetUniformLocation(shaderProgramIrradiance, "model"),
       1, GL_FALSE, glm::value_ptr(model));
     glUniformMatrix4fv(
       glGetUniformLocation(shaderProgramIrradiance, "view"),
       1, GL_FALSE, glm::value_ptr(view));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightView"),
+      1, GL_FALSE, glm::value_ptr(lightView));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightViewInv"),
+      1, GL_FALSE, glm::value_ptr(glm::inverse(lightView)));
     glUniformMatrix4fv(
       glGetUniformLocation(shaderProgramIrradiance, "projection"),
       1, GL_FALSE, glm::value_ptr(proj));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightProjection"),
+      1, GL_FALSE, glm::value_ptr(lightProj));
+    glUniform1i(glGetUniformLocation(shaderProgramIrradiance, "screenWidth"), window.getSize().x);
+    glUniform1i(glGetUniformLocation(shaderProgramIrradiance, "screenHeight"), window.getSize().y);
+    glUniform2fv(glGetUniformLocation(shaderProgramIrradiance, "samplePositions"), 13, samplePositions);
+    glUniform3fv(glGetUniformLocation(shaderProgramIrradiance, "sampleWeights"), 13, sampleWeights);
+
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "transmittanceScale"),
+      options.transmittanceScale);
+    glUniform1i(
+      glGetUniformLocation(shaderProgramIrradiance, "renderState"),
+      options.renderState);
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "powBase"),
+      options.powBase);
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "powFactor"),
+      options.powFactor);
 
     glUniform3fv(
       glGetUniformLocation(shaderProgramIrradiance, "objectColor"),
@@ -543,7 +580,7 @@ int main() {
       1.0f, 1.0f, 1.0f);
     glUniform3fv(
       glGetUniformLocation(shaderProgramIrradiance, "lightPos"),
-      1, glm::value_ptr(lightPos));
+      1, glm::value_ptr(options.lightPos));
     glUniform3fv(
       glGetUniformLocation(shaderProgramIrradiance, "viewPos"),
       1, glm::value_ptr(options.freecam ? freeCam.pos : arcCam.getPos()));
@@ -586,13 +623,18 @@ int main() {
     ImGui::Checkbox("Wireframe", &options.wireframe);
     ImGui::Checkbox("Free Cam", &options.freecam);
     ImGui::InputInt("Render State", &options.renderState);
-    ImGui::InputFloat3("Color", options.color, 2);
+    ImGui::DragFloat3("Color", options.color, 0.01, 0, 1);
+    ImGui::DragFloat("Transmittance Scale", &options.transmittanceScale, 0.0001f, 0, 0.3);
+    ImGui::DragFloat("Pow Base", &options.powBase, 0.01f, 0, 4);
+    ImGui::DragFloat("Pow Factor", &options.powFactor, 0.01f, 0, 3);
+    ImGui::DragFloat3("Light Pos", glm::value_ptr(options.lightPos), 0.01, -5, 5);
     if (options.freecam) {
       ImGui::LabelText("Position", "%f %f %f", freeCam.pos.x, freeCam.pos.y, freeCam.pos.z);
       ImGui::LabelText("Rotation", "%f %f", freeCam.rot.x, freeCam.rot.y);
       if (ImGui::Button("Reset")) {
         freeCam.pos = glm::vec3(0, 0, -1);
         freeCam.rot = glm::vec2(0);
+        options = DefaultOptions;
       }
     } else {
       ImGui::LabelText("Rotation", "%f %f", arcCam.rot.x, arcCam.rot.y);
@@ -600,6 +642,7 @@ int main() {
       if (ImGui::Button("Reset")) {
         arcCam.rot = glm::vec2(0);
         arcCam.radius = 1;
+        options = DefaultOptions;
       }
     }
     ImGui::End();
diff --git a/src/main2.cpp b/src/main2.cpp
new file mode 100644
index 0000000..24a39cc
--- /dev/null
+++ b/src/main2.cpp
@@ -0,0 +1,656 @@
+#include <stdio.h>
+#include <fstream>
+
+#include <GL/glew.h>
+
+#define GLM_ENABLE_EXPERIMENTAL
+
+#include <glm/glm.hpp>
+#include <glm/gtx/rotate_vector.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
+
+#include <SFML/OpenGL.hpp>
+#include <SFML/Graphics.hpp>
+
+#include <imgui.h>
+#include <imgui-SFML.h>
+
+#include <assimp/Importer.hpp>
+#include <assimp/postprocess.h>
+#include <assimp/scene.h>
+
+/*
+
+TODO:
+- Save Depth to fbo
+- Stencil Buffer
+- LightDist > 1
+  - 1 - distanceToBackside in frag_irradiance
+- ShadowMap Perspective (no projection?)
+- (Implement Gaussian Blur)
+- LightDir nicht immer zu 0 0 0
+
+*/
+
+float samplePositions[] = {
+  0.000000f,  0.000000f,
+  1.633992f,  0.036795f,
+  0.177801f,  1.717593f,
+  -0.194906f,  0.091094f,
+  -0.239737f, -0.220217f,
+  -0.003530f, -0.118219f,
+  1.320107f, -0.181542f,
+  5.970690f,  0.253378f,
+  -1.089250f,  4.958349f,
+  -4.015465f,  4.156699f,
+  -4.063099f, -4.110150f,
+  -0.638605f, -6.297663f,
+  2.542348f, -3.245901f
+};
+
+float sampleWeights[] = {
+  0.220441f,  0.487000f, 0.635000f,
+  0.076356f,  0.064487f, 0.039097f,
+  0.116515f,  0.103222f, 0.064912f,
+  0.064844f,  0.086388f, 0.062272f,
+  0.131798f,  0.151695f, 0.103676f,
+  0.025690f,  0.042728f, 0.033003f,
+  0.048593f,  0.064740f, 0.046131f,
+  0.048092f,  0.003042f, 0.000400f,
+  0.048845f,  0.005406f, 0.001222f,
+  0.051322f,  0.006034f, 0.001420f,
+  0.061428f,  0.009152f, 0.002511f,
+  0.030936f,  0.002868f, 0.000652f,
+  0.073580f,  0.023239f, 0.009703f
+};
+
+struct model {
+  std::vector<float> vertices;
+  std::vector<GLuint> indices;
+
+  void draw() {
+    if (VAO == 0) initVAO();
+    glBindVertexArray(VAO);
+    glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0);
+    glBindVertexArray(0);
+  }
+
+private:
+  void initVAO() {
+    GLuint VBO;
+    glGenBuffers(1, &VBO);
+
+    GLuint EBO;
+    glGenBuffers(1, &EBO);
+
+    glGenVertexArrays(1, &VAO);
+
+    glBindVertexArray(VAO);
+
+    glBindBuffer(GL_ARRAY_BUFFER, VBO);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(float) * vertices.size(),
+                vertices.data(), GL_STATIC_DRAW);
+
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(GLuint) * indices.size(),
+                indices.data(), GL_STATIC_DRAW);
+
+    glEnableVertexAttribArray(0);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 6, (void*)(0));
+    glEnableVertexAttribArray(1);
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 6, (void*)(sizeof(float) * 3));
+
+    glBindVertexArray(0);
+  }
+  GLuint VAO = 0;
+};
+
+struct freecam {
+  glm::vec3 pos = glm::vec3(0, 0, -1);
+  glm::vec2 rot = glm::vec2(0, 0);
+
+  void update(sf::Window &window) {
+    int mouseDeltaX = sf::Mouse::getPosition(window).x - window.getSize().x / 2;
+    int mouseDeltaY = sf::Mouse::getPosition(window).y - window.getSize().y / 2;
+
+    rot.x += mouseDeltaX;
+    rot.y += mouseDeltaY;
+
+    forward = glm::rotate(glm::vec3(0, 0, 1), rot.y / angleFactor, glm::vec3(1, 0, 0));
+    forward = glm::rotate(forward, -rot.x / angleFactor, glm::vec3(0, 1, 0));
+
+    glm::vec3 left = glm::rotate(glm::vec3(0, 0, 1), -rot.x / angleFactor + glm::radians(90.0f), glm::vec3(0, 1, 0));
+
+    if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::LShift))
+      moveFactor = 200;
+    else
+      moveFactor = 20;
+
+    if (sf::Keyboard::isKeyPressed(sf::Keyboard::W))
+      pos += forward / moveFactor;
+    if (sf::Keyboard::isKeyPressed(sf::Keyboard::S))
+      pos -= forward / moveFactor;
+    if (sf::Keyboard::isKeyPressed(sf::Keyboard::A))
+      pos += left / moveFactor;
+    if (sf::Keyboard::isKeyPressed(sf::Keyboard::D))
+      pos -= left / moveFactor;
+
+    limit();
+  }
+
+  void limit() {
+    rot.x = fmod(rot.x, glm::radians(360.0f) * angleFactor);
+    rot.y = fmod(rot.y, glm::radians(360.0f) * angleFactor);
+  }
+
+  glm::mat4 getViewMatrix() {
+    forward = glm::rotate(glm::vec3(0, 0, 1), rot.y / angleFactor, glm::vec3(1, 0, 0));
+    forward = glm::rotate(forward, -rot.x / angleFactor, glm::vec3(0, 1, 0));
+    glm::mat4 result = glm::lookAt(pos, pos + forward, up);
+    return result;
+  }
+
+private:
+  glm::vec3 forward = glm::vec3(0, 0, 1);
+  glm::vec3 up = glm::vec3(0, 1, 0);
+
+  const float angleFactor = 200;
+  float moveFactor = 20;
+};
+
+struct arccam {
+  glm::vec2 rot = glm::vec2(0, 0);
+  float radius = 1;
+
+  void update(sf::Window &window) {
+    int mouseDeltaX = sf::Mouse::getPosition(window).x - window.getSize().x / 2;
+    int mouseDeltaY = sf::Mouse::getPosition(window).y - window.getSize().y / 2;
+
+    rot.x += mouseDeltaX;
+    rot.y += mouseDeltaY;
+
+    limit(-89, 89);
+  }
+
+  void limit(float minY, float maxY) {
+    float angleX = rot.x / angleFactor;
+    float angleY = rot.y / angleFactor;
+
+    rot.x = fmod(rot.x, glm::radians(360.0f) * angleFactor);
+
+    if (angleY > glm::radians(maxY))
+      rot.y = glm::radians(maxY) * angleFactor;
+    if (angleY < glm::radians(minY))
+      rot.y = glm::radians(minY) * angleFactor;
+  }
+
+  glm::vec3 getPos() {
+    float angle = rot.y / angleFactor;
+  
+    float camY = sin(angle) * exp(radius);
+    float camZ = cos(angle) * exp(radius);
+
+    glm::vec3 result(0.0, camY, camZ);
+    return glm::rotate(result, -rot.x / angleFactor, glm::vec3(0, 1, 0));
+  }
+
+  glm::mat4 getViewMatrix() {
+    float angle = rot.y / angleFactor;
+  
+    float camY = sin(angle) * exp(radius);
+    float camZ = cos(angle) * exp(radius);
+    glm::mat4 result = glm::lookAt(glm::vec3(0.0, camY, camZ), glm::vec3(0, 0, 0), glm::vec3(0, 1, 0));
+    result = glm::rotate(result, rot.x / angleFactor, glm::vec3(0, 1, 0));
+
+    return result;
+  }
+
+private:
+  const float angleFactor = 200;
+};
+
+std::string readFile(std::string filename) {
+  std::ifstream ifs(filename, std::ios::binary);
+  std::string result, line;
+  while (std::getline(ifs, line))
+    result += line + "\n";
+
+  return result;
+}
+
+model loadModel(const std::string &filename) {
+  Assimp::Importer importer;
+
+  const aiScene *scene = importer.ReadFile(
+      filename, aiProcess_CalcTangentSpace | aiProcess_Triangulate |
+                    aiProcess_SortByPType | aiProcess_GenSmoothNormals |
+                    aiProcess_GenUVCoords);
+
+  model result;
+
+  printf("uv channels: %d\n", scene->mMeshes[0]->GetNumUVChannels());
+
+  for (int i = 0; i < scene->mMeshes[0]->mNumVertices; i++) {
+    aiVector3D v = scene->mMeshes[0]->mVertices[i];
+    aiVector3D n = scene->mMeshes[0]->mNormals[i];
+    result.vertices.push_back(v.x * 100);
+    result.vertices.push_back(v.y * 100);
+    result.vertices.push_back(v.z * 100);
+    result.vertices.push_back(n.x * 100);
+    result.vertices.push_back(n.y * 100);
+    result.vertices.push_back(n.z * 100);
+  }
+
+  for (int i = 0; i < scene->mMeshes[0]->mNumFaces; i++) {
+    aiFace f = scene->mMeshes[0]->mFaces[i];
+    for (int j = 0; j < f.mNumIndices; j++) {
+      result.indices.push_back(f.mIndices[j]);
+    }
+  }
+
+  return result;
+}
+
+GLuint compileShaders(const char *vertFilename, const char *fragFilename) {
+  GLuint vertShader = glCreateShader(GL_VERTEX_SHADER);
+  std::string vertSource = readFile(vertFilename);
+  const char *vertAddr = vertSource.c_str();
+  glShaderSource(vertShader, 1, &vertAddr, NULL);
+  glCompileShader(vertShader);
+
+  int success;
+  char infoLog[512];
+  glGetShaderiv(vertShader, GL_COMPILE_STATUS, &success);
+  if (!success) {
+    glGetShaderInfoLog(vertShader, 512, NULL, infoLog);
+    printf("Error compiling vertex shader(%s): %s\n", vertFilename, infoLog);
+  }
+
+  GLuint fragShader = glCreateShader(GL_FRAGMENT_SHADER);
+  std::string fragSource = readFile(fragFilename);
+  const char *fragAddr = fragSource.c_str();
+  glShaderSource(fragShader, 1, &fragAddr, NULL);
+  glCompileShader(fragShader);
+
+  glGetShaderiv(fragShader, GL_COMPILE_STATUS, &success);
+  if (!success) {
+    glGetShaderInfoLog(fragShader, 512, NULL, infoLog);
+    printf("Error compiling fragment shader(%s): %s\n", fragFilename, infoLog);
+  }
+
+  // Link Shader Program
+
+  GLuint shaderProgram = glCreateProgram();
+  glAttachShader(shaderProgram, vertShader);
+  glAttachShader(shaderProgram, fragShader);
+  glLinkProgram(shaderProgram);
+
+  glGetProgramiv(shaderProgram, GL_LINK_STATUS, &success);
+  if (!success) {
+    glGetProgramInfoLog(shaderProgram, 512, NULL, infoLog);
+    printf("Error linking shader program: %s\n", infoLog);
+  }
+
+  glDeleteShader(vertShader);
+  glDeleteShader(fragShader);
+
+  return shaderProgram;
+}
+
+struct framebuffer {
+  framebuffer(const char *vertFilename, const char *fragFilename, int width, int height) {
+    glGenFramebuffers(1, &fbo);
+    glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+    
+    glGenTextures(1, &renderTexture);
+    glBindTexture(GL_TEXTURE_2D, renderTexture);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    //glBindTexture(GL_TEXTURE_2D, 0);
+    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, renderTexture, 0);
+
+    glGenRenderbuffers(1, &rbo);
+    glBindRenderbuffer(GL_RENDERBUFFER, rbo);
+    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, width, height);
+    //glBindRenderbuffer(GL_RENDERBUFFER, 0);
+    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, rbo);
+
+    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) == GL_FRAMEBUFFER_COMPLETE) {
+      printf("Successfully created framebuffer\n");
+    }
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    
+    screenShaderProgram = compileShaders(vertFilename, fragFilename);
+    glUseProgram(screenShaderProgram);
+    glUniform1i(glGetUniformLocation(screenShaderProgram, "screenTexture"), 0);
+
+    // Screen VAO
+    
+    glGenBuffers(1, &screenVBO);
+
+    glGenVertexArrays(1, &screenVAO);
+
+    glBindVertexArray(screenVAO);
+
+    float screenVerts[] = {
+      -1.0f, +1.0f, +0.0f, +1.0f,
+      -1.0f, -1.0f, +0.0f, +0.0f,
+      +1.0f, -1.0f, +1.0f, +0.0f,
+  
+      -1.0f, +1.0f, +0.0f, +1.0f,
+      +1.0f, -1.0f, +1.0f, +0.0f,
+      +1.0f, +1.0f, +1.0f, +1.0f,
+    };
+
+    glBindBuffer(GL_ARRAY_BUFFER, screenVBO);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 6 * 4,
+                screenVerts, GL_STATIC_DRAW);
+
+    glEnableVertexAttribArray(0);
+    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, (void*)(0));
+    glEnableVertexAttribArray(1);
+    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, (void*)(sizeof(float) * 2));
+
+    glBindVertexArray(0);
+  }
+  ~framebuffer() {
+    glDeleteFramebuffers(1, &fbo);
+  }
+  
+  GLuint fbo;
+  GLuint renderTexture;
+  GLuint rbo;
+  GLuint screenShaderProgram;
+  GLuint screenVBO;
+  GLuint screenVAO;
+};
+
+int main() {
+  // Window Setup
+
+  const int width = 1600, height = 900;
+
+  sf::ContextSettings settings;
+  settings.depthBits = 24;
+  settings.antialiasingLevel = 0;
+  settings.majorVersion = 4;
+  settings.minorVersion = 6;
+
+  sf::RenderWindow window(sf::VideoMode(1600, 900), "Subsurface Scattering",
+                    sf::Style::Default, settings);
+  window.setVerticalSyncEnabled(true);
+
+  ImGui::SFML::Init(window);
+
+  // Initialize GLEW
+
+  if (glewInit() != GLEW_OK) {
+  }
+
+  GLuint shaderProgramShadowmap = compileShaders("shaders/vert_shadowmap.glsl", "shaders/frag_shadowmap.glsl");
+  GLuint shaderProgramIrradiance = compileShaders("shaders/vert_irradiance.glsl", "shaders/frag_irradiance.glsl");
+
+  //model m = loadModel("models/Isotrop-upperjaw.ply");
+  model m = loadModel("models/african_head/african_head.obj");
+
+  arccam arcCam;
+  freecam freeCam;
+
+  // MVP
+
+  glm::mat4 model = glm::scale(glm::mat4(1.0f), glm::vec3(0.01f, 0.01f, 0.01f));
+
+  glm::mat4 view, lightView;
+
+  glm::mat4 proj = glm::perspective(glm::radians(45.0f), (float)window.getSize().x / window.getSize().y, 0.001f, 1000.0f);
+  glm::mat4 lightProj = glm::perspective(glm::radians(90.0f), (float)window.getSize().x / window.getSize().y, 0.001f, 1000.0f);
+
+  // Framebuffer
+  framebuffer fb_shadowmap("shaders/fbo_vert.glsl", "shaders/fbo_frag.glsl", width, height);
+  framebuffer fb_irradiance("shaders/fbo_vert.glsl", "shaders/fbo_frag.glsl", width, height);
+
+  // Config
+
+  const struct {
+    bool wireframe = false;
+    bool freecam = false;
+    int renderState = 2;
+    float color[3] = { 0.7f, 0.4f, 0.4f };
+    glm::vec3 lightPos = glm::vec3(0.0f, 0.04f, -0.08f);
+    float transmittanceScale = 0.005f;
+    float powBase = 2.718;
+    float powFactor = 1;
+  } DefaultOptions;
+
+  auto options = DefaultOptions;
+
+  sf::Clock deltaClock;
+
+  bool prevMouse = false;
+
+  bool running = true;
+  while (running) {
+    // Events
+
+    sf::Event event;
+    while (window.pollEvent(event)) {
+      ImGui::SFML::ProcessEvent(event);
+
+      if (event.type == sf::Event::EventType::Closed) {
+        running = false;
+      } else if (event.type == sf::Event::EventType::Resized) {
+        glViewport(0, 0, event.size.width, event.size.height);
+      } else if (event.type == sf::Event::EventType::KeyReleased) {
+        using keys = sf::Keyboard;
+        switch (event.key.code) {
+        case keys::Escape:
+          running = false;
+          break;
+        }
+      } else if (event.type == sf::Event::EventType::MouseWheelScrolled) {
+        if (! options.freecam) {
+          arcCam.radius -= event.mouseWheelScroll.delta / 5.0f;
+        }
+      }
+    }
+
+    // Update
+
+    if (sf::Mouse::isButtonPressed(sf::Mouse::Right)) {
+      window.setMouseCursorVisible(false);
+
+      if (prevMouse) {
+        if (options.freecam)
+          freeCam.update(window);
+        else
+          arcCam.update(window);
+      }
+
+
+      sf::Mouse::setPosition(sf::Vector2i(
+          window.getSize().x / 2,
+          window.getSize().y / 2
+        ), window);  
+    } else {
+      window.setMouseCursorVisible(true);
+    }
+
+    prevMouse = sf::Mouse::isButtonPressed(sf::Mouse::Right);
+
+    // Render Shadowmap
+
+    glClampColor(GL_CLAMP_READ_COLOR, GL_FALSE);
+    glClampColor(GL_CLAMP_VERTEX_COLOR, GL_FALSE);
+    glClampColor(GL_CLAMP_FRAGMENT_COLOR, GL_FALSE);
+
+    glBindFramebuffer(GL_FRAMEBUFFER, fb_shadowmap.fbo);
+    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glEnable(GL_DEPTH_TEST);
+
+    if (options.wireframe)
+      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+    else
+      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+
+    glUseProgram(shaderProgramShadowmap);
+    
+    if (options.freecam)
+      view = freeCam.getViewMatrix();
+    else
+      view = arcCam.getViewMatrix();
+    
+    lightView = glm::lookAt(options.lightPos, glm::vec3(0, 0, 0), glm::vec3(0, 1, 0));
+    
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramShadowmap, "model"),
+      1, GL_FALSE, glm::value_ptr(model));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramShadowmap, "lightView"),
+      1, GL_FALSE, glm::value_ptr(lightView));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramShadowmap, "projection"),
+      1, GL_FALSE, glm::value_ptr(lightProj));
+
+    glUniform3fv(
+      glGetUniformLocation(shaderProgramShadowmap, "lightPos"),
+      1, glm::value_ptr(options.lightPos));
+
+    m.draw();
+
+    // Render irradiance
+
+    glBindFramebuffer(GL_FRAMEBUFFER, fb_irradiance.fbo);
+    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glEnable(GL_DEPTH_TEST);
+
+    if (options.wireframe)
+      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+    else
+      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+
+    glUseProgram(shaderProgramIrradiance);
+    
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "model"),
+      1, GL_FALSE, glm::value_ptr(model));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "view"),
+      1, GL_FALSE, glm::value_ptr(view));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightView"),
+      1, GL_FALSE, glm::value_ptr(lightView));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightViewInv"),
+      1, GL_FALSE, glm::value_ptr(glm::inverse(lightView)));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "projection"),
+      1, GL_FALSE, glm::value_ptr(proj));
+    glUniformMatrix4fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightProjection"),
+      1, GL_FALSE, glm::value_ptr(lightProj));
+    glUniform1i(glGetUniformLocation(shaderProgramIrradiance, "screenWidth"), window.getSize().x);
+    glUniform1i(glGetUniformLocation(shaderProgramIrradiance, "screenHeight"), window.getSize().y);
+    glUniform2fv(glGetUniformLocation(shaderProgramIrradiance, "samplePositions"), 13, samplePositions);
+    glUniform3fv(glGetUniformLocation(shaderProgramIrradiance, "sampleWeights"), 13, sampleWeights);
+
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "transmittanceScale"),
+      options.transmittanceScale);
+    glUniform1i(
+      glGetUniformLocation(shaderProgramIrradiance, "renderState"),
+      options.renderState);
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "powBase"),
+      options.powBase);
+    glUniform1f(
+      glGetUniformLocation(shaderProgramIrradiance, "powFactor"),
+      options.powFactor);
+
+    glUniform3fv(
+      glGetUniformLocation(shaderProgramIrradiance, "objectColor"),
+      1, options.color);
+    glUniform3f(
+      glGetUniformLocation(shaderProgramIrradiance, "lightColor"),
+      1.0f, 1.0f, 1.0f);
+    glUniform3fv(
+      glGetUniformLocation(shaderProgramIrradiance, "lightPos"),
+      1, glm::value_ptr(options.lightPos));
+    glUniform3fv(
+      glGetUniformLocation(shaderProgramIrradiance, "viewPos"),
+      1, glm::value_ptr(options.freecam ? freeCam.pos : arcCam.getPos()));
+      
+    glUniform1i(glGetUniformLocation(shaderProgramIrradiance, "shadowmapTexture"), 0);
+    glActiveTexture(GL_TEXTURE0 + 0);
+    glBindTexture(GL_TEXTURE_2D, fb_shadowmap.renderTexture);
+
+    m.draw();
+
+    // Render fbo to screen
+    
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    glDisable(GL_DEPTH_TEST);
+    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT);
+    glUseProgram(fb_irradiance.screenShaderProgram);
+
+    glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "screenWidth"), window.getSize().x);
+    glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "screenHeight"), window.getSize().y);
+    glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "renderState"), options.renderState);
+    glUniform2fv(glGetUniformLocation(fb_irradiance.screenShaderProgram, "samplePositions"), 13, samplePositions);
+    glUniform3fv(glGetUniformLocation(fb_irradiance.screenShaderProgram, "sampleWeights"), 13, sampleWeights);
+
+    glBindVertexArray(fb_irradiance.screenVAO);
+    glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "shadowmapTexture"), 0);
+    glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "irradianceTexture"), 1);
+    glActiveTexture(GL_TEXTURE0 + 0);
+    glBindTexture(GL_TEXTURE_2D, fb_shadowmap.renderTexture);
+    glActiveTexture(GL_TEXTURE0 + 1);
+    glBindTexture(GL_TEXTURE_2D, fb_irradiance.renderTexture);
+    glDrawArrays(GL_TRIANGLES, 0, 6);
+    glBindVertexArray(0);
+
+    ImGui::SFML::Update(window, deltaClock.restart());
+
+    ImGui::Begin("Options");
+    ImGui::Checkbox("Wireframe", &options.wireframe);
+    ImGui::Checkbox("Free Cam", &options.freecam);
+    ImGui::InputInt("Render State", &options.renderState);
+    ImGui::DragFloat3("Color", options.color, 0.01, 0, 1);
+    ImGui::DragFloat("Transmittance Scale", &options.transmittanceScale, 0.0001f, 0, 0.3);
+    ImGui::DragFloat("Pow Base", &options.powBase, 0.01f, 0, 4);
+    ImGui::DragFloat("Pow Factor", &options.powFactor, 0.01f, 0, 3);
+    ImGui::DragFloat3("Light Pos", glm::value_ptr(options.lightPos), 0.01, -5, 5);
+    if (options.freecam) {
+      ImGui::LabelText("Position", "%f %f %f", freeCam.pos.x, freeCam.pos.y, freeCam.pos.z);
+      ImGui::LabelText("Rotation", "%f %f", freeCam.rot.x, freeCam.rot.y);
+      if (ImGui::Button("Reset")) {
+        freeCam.pos = glm::vec3(0, 0, -1);
+        freeCam.rot = glm::vec2(0);
+        options = DefaultOptions;
+      }
+    } else {
+      ImGui::LabelText("Rotation", "%f %f", arcCam.rot.x, arcCam.rot.y);
+      ImGui::DragFloat("Radius", &arcCam.radius, 0.01f, -1.0f, 1.0f);
+      if (ImGui::Button("Reset")) {
+        arcCam.rot = glm::vec2(0);
+        arcCam.radius = 1;
+        options = DefaultOptions;
+      }
+    }
+    ImGui::End();
+
+    ImGui::SFML::Render(window);
+
+    window.display();
+  }
+
+  return 0;
+}