Screen Space SSS

2 files changed, 35 insertions, 4 deletions

diff --git a/shaders/fbo_frag.glsl b/shaders/fbo_frag.glsl
index cf1fafa..f6f12cd 100644
--- a/shaders/fbo_frag.glsl
+++ b/shaders/fbo_frag.glsl
@@ -4,10 +4,30 @@ out vec4 FragColor;
 in vec2 TexCoords;

 

 uniform sampler2D screenTexture;

+uniform int applySSSSS;

+uniform int N;

 

 void main()

-{ 

-    FragColor = vec4(

-        texture(screenTexture, TexCoords).rgb,

-        1.0);

+{

+    if (applySSSSS == 1) {

+        float x = 1.0/1600.0;

+        float y = 1.0/900.0;

+

+        float maxDist = N*N + N*N;

+

+        vec4 color = vec4(0, 0, 0, 1);

+        for (int i = -N; i <= N; i++) {

+            for (int j = -N; j <= N; j++) {

+                float dist = i*i + j*j;

+                vec4 newC = texture(screenTexture, TexCoords + vec2(i*x, j*y)) / (2*N*N);

+                float factor = 1 - (dist / maxDist);

+                factor = pow(factor, 2);

+                color += newC * factor;

+            }

+        }

+        FragColor = color;

+    }

+    else {

+        FragColor = texture(screenTexture, TexCoords);

+    }

 }

diff --git a/src/main.cpp b/src/main.cpp
index 41d5e76..4168c50 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -304,6 +304,8 @@ int main() {
   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);

 

@@ -359,6 +361,8 @@ int main() {
   struct {

     bool wireframe = false;

     bool freecam = false;

+    bool sssss = false;

+    int N = 2;

   } options;

 

   sf::Clock deltaClock;

@@ -468,6 +472,9 @@ int main() {
     glClear(GL_COLOR_BUFFER_BIT);

     glUseProgram(screenShaderProgram);

 

+    glUniform1i(glGetUniformLocation(screenShaderProgram, "applySSSSS"), options.sssss);

+    glUniform1i(glGetUniformLocation(screenShaderProgram, "N"), options.N);

+

     glBindVertexArray(screenVAO);

     glBindTexture(GL_TEXTURE_2D, renderTexture);

     glDrawArrays(GL_TRIANGLES, 0, 6);

@@ -478,6 +485,10 @@ int main() {
     ImGui::Begin("Options");

     ImGui::Checkbox("Wireframe", &options.wireframe);

     ImGui::Checkbox("Free Cam", &options.freecam);

+    ImGui::Checkbox("SSSSS", &options.sssss);

+    if (options.sssss) {

+      ImGui::DragInt("N", &options.N, 0.05f, 1, 16);

+    }

     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);