comments TS SSS

6 files changed, 28 insertions, 110 deletions

diff --git a/shaders/ts_frag.glsl b/shaders/ts_frag.glsl
index a0a8457..9362e2a 100644
--- a/shaders/ts_frag.glsl
+++ b/shaders/ts_frag.glsl
@@ -20,42 +20,7 @@ uniform float transmittanceScale;
 

 void main()

 {

-  if (renderState == 0) {

-    FragColor = texture(irradianceTexture, UV);

-  }

-  else if (renderState == 1) {

-    vec3 norm = normalize(Normal);

-    vec3 lightDir = normalize(lightPos - FragPos);

-

-    float diff = max(dot(norm, lightDir), 0.0);

-    vec3 diffuse = diff * lightColor;

-

-    float ambientStrength = 0.1;

-    vec3 ambient = ambientStrength * lightColor;

-

-    float specularStrength = 0.5;

-    vec3 viewDir = normalize(viewPos - FragPos);

-    vec3 reflectDir = reflect(-lightDir, norm);

-    float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);

-    vec3 specular = specularStrength * spec * lightColor;

-

-    vec3 result = (ambient + diffuse + specular) * objectColor;

-      

-    FragColor = vec4(result, 1.0);

-  }

-  else if (renderState == 2) {

-    vec4 result = vec4(0, 0, 0, 1);

-    for (int i = 0; i < 13; i++) {

-        vec2 sampleCoords = UV + samplePositions[i] * vec2(1.0/screenWidth, 1.0/screenHeight);

-        //vec4 sample = texture(irradianceTexture, sampleCoords)

-        //            * texture(shadowmapTexture, sampleCoords);

-        vec4 sample = texture(irradianceTexture, sampleCoords);

-        vec4 weight = vec4(sampleWeights[i], 1);

-        result += sample * weight;

-    }

-    FragColor = result;

-  }

-  else if (renderState == 3) {

+    // light the model

     vec3 norm = normalize(Normal);

     vec3 lightDir = normalize(lightPos - FragPos);

 

@@ -73,28 +38,34 @@ void main()
 

     vec3 result = vec3((ambient + diffuse + specular) * objectColor);

 

+    // sample irradiance as distance to light combined with angle to the light

+    // with a Gaussian kernel

     vec3 result2 = vec3(0, 0, 0);

     for (int i = 0; i < 13; i++) {

         vec2 sampleCoords = UV + samplePositions[i] * vec2(1.0/screenWidth, 1.0/screenHeight);

         //vec4 sample = texture(irradianceTexture, sampleCoords)

         //            * texture(shadowmapTexture, sampleCoords);

-        vec3 sample = vec3(texture(irradianceTexture, sampleCoords));

+        vec3 sample = vec3(texture(irradianceTexture, sampleCoords)) * diff;

         vec3 weight = sampleWeights[i];

         result2 += sample * weight;

     }

 

+    // multiply to apply irradiance, sqrt to get values between 0 and 1

     result = sqrt(result * result2);

     

+    // sample texture to get distance from light

     vec4 t = texture(irradianceTexture, UV);

-

     float BacksideIrradiance = t.r; //*100 + t.g + t.b/100;

-    

+    // and calculate world pos

     vec3 Backside = (lightPos + (normalize(FragPos - lightPos) * BacksideIrradiance));

     

+    // add translucency by amplifying color inverse to the thickness

+    // (1 - diff) is part of the irradiance term,

+    // if the light hits the object straight at 90°

+    // most light is received

     float distanceToBackside = length(FragPos - Backside);

     if (distanceToBackside != 0)

       result += objectColor * exp(2 / pow(distanceToBackside, 0.6)) * transmittanceScale * (1 - diff);

 

     FragColor = vec4(result, 1);

-  }

 }

diff --git a/shaders/ts_frag_irradiance.glsl b/shaders/ts_frag_irradiance.glsl
index b9e70ae..37d28f1 100644
--- a/shaders/ts_frag_irradiance.glsl
+++ b/shaders/ts_frag_irradiance.glsl
@@ -10,52 +10,11 @@ uniform vec3 lightColor;
 uniform vec3 objectColor;

 uniform vec3 viewPos;

 

-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()

 {

-  vec3 norm = normalize(Normal);

-  vec3 lightDir = normalize(lightPos - FragPos);

-

-  float diff = max(dot(norm, lightDir), 0.0);

-  vec3 diffuse = diff * lightColor;

-

-  float ambientStrength = 0.1;

-  vec3 ambient = ambientStrength * lightColor;

-

-  float specularStrength = 0.5;

-  vec3 viewDir = normalize(viewPos - FragPos);

-  vec3 reflectDir = reflect(-lightDir, norm);

-  float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);

-  vec3 specular = specularStrength * spec * lightColor;

-

-  vec3 result = (ambient + diffuse) * objectColor;

-

-  result = vec3(length(FragPos - lightPos));

+  // color the XY-plane according to the distance

+  // of the fragment in world space

+  vec3 result = vec3(length(FragPos - lightPos));

     

   FragColor = vec4(result, 1.0f);

 }

diff --git a/shaders/ts_vert.glsl b/shaders/ts_vert.glsl
index f8e790a..3ee202f 100644
--- a/shaders/ts_vert.glsl
+++ b/shaders/ts_vert.glsl
@@ -14,6 +14,7 @@ uniform mat4 projection;
 

 void main()

 {

+  // regular mvp

   gl_Position = projection * view * model * vec4(pos, 1.0);

   FragPos = vec3(model * vec4(pos, 1.0));

   Normal = normal;

diff --git a/shaders/ts_vert_irradiance.glsl b/shaders/ts_vert_irradiance.glsl
index afe5645..f0d77b9 100644
--- a/shaders/ts_vert_irradiance.glsl
+++ b/shaders/ts_vert_irradiance.glsl
@@ -13,7 +13,9 @@ uniform mat4 projection;
 

 void main()

 {

-  FragPos = vec3(model * vec4(pos, 1.0));

+  // lay out the model in the XY-plane according to it's UV coordinates

   gl_Position = vec4(uv * 2.0 - 1.0, 0.0, 1.0);

+  // pass fragment position in world coordinates

+  FragPos = vec3(model * vec4(pos, 1.0));

   Normal = normal;

 }

diff --git a/src/main.cpp b/src/main.cpp
index 8b48e70..168d01d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -20,18 +20,9 @@
 #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

-

-*/

+

+// sample positions and weights for a Gaussian kernel from 

+// Hable, John ; Borshukov, George ; Hejl, Jim: Fast Skin Shading. In: ShaderX7, ShaderX : Charles River Media, 2009, S. 161–173

 

 float samplePositions[] = {

   0.000000f,  0.000000f,

diff --git a/src/main2.cpp b/src/main2.cpp
index 206466d..5d717e6 100644
--- a/src/main2.cpp
+++ b/src/main2.cpp
@@ -20,6 +20,10 @@
 #include <assimp/postprocess.h>

 #include <assimp/scene.h>

 

+

+// sample positions and weights for a Gaussian kernel from 

+// Hable, John ; Borshukov, George ; Hejl, Jim: Fast Skin Shading. In: ShaderX7, ShaderX : Charles River Media, 2009, S. 161–173

+

 float samplePositions[] = {

   0.000000f,  0.000000f,

   1.633992f,  0.036795f,

@@ -383,7 +387,6 @@ int main() {
   GLuint shaderProgramIrradiance = compileShaders("shaders/ts_vert_irradiance.glsl", "shaders/ts_frag_irradiance.glsl");

   GLuint shaderProgramCombine = compileShaders("shaders/ts_vert.glsl", "shaders/ts_frag.glsl");

 

-  //model m = loadModel("models/Isotrop-upperjaw.ply");

   model m = loadModel("models/african_head/african_head.obj");

 

   arccam arcCam;

@@ -470,7 +473,7 @@ int main() {
 

     prevMouse = sf::Mouse::isButtonPressed(sf::Mouse::Right);

 

-    // Render Shadowmap

+    // Render Shadowmap to fbo

 

     glBindFramebuffer(GL_FRAMEBUFFER, fb_irradiance.fbo);

     glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

@@ -514,9 +517,7 @@ int main() {
 

     m.draw();

 

-    

-

-    // Render fbo to screen

+    // Render model and calculate light spread and translucency in shader

 

     glBindFramebuffer(GL_FRAMEBUFFER, 0);

     glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

@@ -569,16 +570,9 @@ int main() {
     glActiveTexture(GL_TEXTURE0 + 0);

     glBindTexture(GL_TEXTURE_2D, fb_irradiance.renderTexture);

 

-    // glBindVertexArray(fb_irradiance.screenVAO);

-    // glUniform1i(glGetUniformLocation(fb_irradiance.screenShaderProgram, "shadowmapTexture"), 0);

-    // glActiveTexture(GL_TEXTURE0 + 0);

-    // glBindTexture(GL_TEXTURE_2D, fb_irradiance.renderTexture);

-    // glDrawArrays(GL_TRIANGLES, 0, 6);

-    // glBindVertexArray(0);

-

     m.draw();

 

-

+    // menu

 

     ImGui::SFML::Update(window, deltaClock.restart());