From c1c7597f5a0e8ec6c50937725bf29670737449cd Mon Sep 17 00:00:00 2001
From: Perminder <permindersingh089@gmail.com>
Date: Sat, 1 Jun 2024 05:02:53 +0530
Subject: [PATCH] fog-added

Signed-off-by: Perminder <permindersingh089@gmail.com>
---
 avogadro/rendering/solid_first_fs.glsl | 33 ++++++++++++++++++++++----
 avogadro/rendering/solidpipeline.cpp   | 14 +++++++++--
 avogadro/rendering/solidpipeline.h     | 22 +++++++++++++++++
 3 files changed, 62 insertions(+), 7 deletions(-)

diff --git a/avogadro/rendering/solid_first_fs.glsl b/avogadro/rendering/solid_first_fs.glsl
index b95274fdc6..76570075b5 100644
--- a/avogadro/rendering/solid_first_fs.glsl
+++ b/avogadro/rendering/solid_first_fs.glsl
@@ -21,10 +21,18 @@ varying vec2 UV;
 
 // RGB rendered texture
 uniform sampler2D inRGBTex;
+
+// RGB color for applying fog
+uniform float fogR;
+uniform float fogG;
+uniform float fogB;
+
 // Depth rendered texture
 uniform sampler2D inDepthTex;
 // 1.0 if enabled, 0.0 if disabled
 uniform float inAoEnabled;
+// 1.0 if enabled, 0.0 if disabled
+uniform float inFogEnabled;
 // Shadow strength for SSAO
 uniform float inAoStrength;
 // 1.0 if enabled, 0.0 if disabled
@@ -66,6 +74,15 @@ float lerp(float a, float b, float f)
     return a + f * (b - a);
 }
 
+vec4 applyFog(vec2 texCoord) {
+  vec4 finalColor = mix(
+    texture2D(inRGBTex, texCoord),
+    vec4(vec3(fogR, fogG, fogB), 1.),
+    pow(texture2D(inDepthTex, texCoord.xy).r, 300.)
+  );
+return finalColor;
+}
+
 const vec2 SSAOkernel[16] = vec2[16](
   vec2(0.072170, 0.081556),
   vec2(-0.035126, 0.056701),
@@ -113,13 +130,19 @@ float computeEdgeLuminosity(vec3 normal)
   return max(0.0, pow(normal.z - 0.1, 1.0 / 3.0));
 }
 
-void main()
-{
+void main() {
   float luminosity = 1.0;
   luminosity *= max(1.2 * (1.0 - inAoEnabled), computeSSAOLuminosity(getNormalNear(UV)));
   luminosity *= max(1.0 - inEdStrength, computeEdgeLuminosity(getNormalAt(UV)));
-
   vec4 color = texture2D(inRGBTex, UV);
-  gl_FragColor = vec4(color.xyz * luminosity, color.w);
+  if(inFogEnabled == 0.0){
+    gl_FragColor = vec4(color.xyz * luminosity, color.w);
+  }
+  else {
+  // Apply fog to the color texture
+    vec4 foggedColor = applyFog(UV);
+    vec4 fogColor = vec4(luminosity * foggedColor.xyz, foggedColor.w);
+    gl_FragColor = fogColor;
+  }
   gl_FragDepth = texture2D(inDepthTex, UV).x;
-}
+}
\ No newline at end of file
diff --git a/avogadro/rendering/solidpipeline.cpp b/avogadro/rendering/solidpipeline.cpp
index a313d99b82..1fcf18e2e0 100644
--- a/avogadro/rendering/solidpipeline.cpp
+++ b/avogadro/rendering/solidpipeline.cpp
@@ -7,6 +7,7 @@
 
 #include "avogadrogl.h"
 #include "shader.h"
+#include "camera.h"
 #include "shaderprogram.h"
 
 #include "solid_vs.h"
@@ -87,7 +88,7 @@ void initializeFramebuffer(GLuint* outFBO, GLuint* texRGB, GLuint* texDepth)
 SolidPipeline::SolidPipeline()
   : m_pixelRatio(1.0f), m_aoEnabled(true), m_aoStrength(1.0f),
     m_edEnabled(true), m_edStrength(1.0f), m_width(0), m_height(0),
-    d(new Private)
+    d(new Private), m_backgroundColor(0,0,0,0)
 {
 }
 
@@ -158,8 +159,17 @@ void SolidPipeline::end()
   d->firstStageShaders.setUniformValue("inAoEnabled", m_aoEnabled ? 1.0f : 0.0f);
   d->firstStageShaders.setUniformValue("inAoStrength", m_aoStrength);
   d->firstStageShaders.setUniformValue("inEdStrength", m_edStrength);
+  d->firstStageShaders.setUniformValue("inFogEnabled", m_fogEnabled ? 1.0f : 0.0f);
+  d->firstStageShaders.setUniformValue("fogR", (m_backgroundColor[0])/255.0f);
+  d->firstStageShaders.setUniformValue("fogG", (m_backgroundColor[1])/255.0f);
+  d->firstStageShaders.setUniformValue("fogB", (m_backgroundColor[2])/255.0f);
   glDrawArrays(GL_TRIANGLES, 0, 6);
-
+  
+  // TODO: setting modelView uniform. WIP
+  Camera camera;
+  camera.setModelView(modelView);
+  modelView = camera.modelView();
+  // std::cout << modelView.matrix();
   glDisableVertexAttribArray(0);
 }
 
diff --git a/avogadro/rendering/solidpipeline.h b/avogadro/rendering/solidpipeline.h
index 8c982bdc2d..bc8de62c43 100644
--- a/avogadro/rendering/solidpipeline.h
+++ b/avogadro/rendering/solidpipeline.h
@@ -6,6 +6,8 @@
 #ifndef AVOGADRO_RENDERING_SOLIDPIPELINE_H
 #define AVOGADRO_RENDERING_SOLIDPIPELINE_H
 
+#include "camera.h"
+
 namespace Avogadro {
 namespace Rendering {
 
@@ -52,6 +54,23 @@ class SolidPipeline
   bool getAoEnabled() { return m_aoEnabled; }
   void setAoEnabled(bool enabled) { m_aoEnabled = enabled; }
 
+  /**
+   * @brief Get or set whether Fog is enabled.
+   */
+  bool getFogEnabled() { return m_fogEnabled; }
+  void setFogEnabled(bool enabled) { m_fogEnabled = enabled; }
+
+  /**
+   * @brief Set the modelViewMatrix to its updated one.  
+   */
+  void setModelViewMatrix(const Eigen::Affine3f value) { modelView = value; }
+
+  /**
+   * @brief Set Background Color to it's current value.
+   */  
+  Vector4ub backgroundColor() const { return m_backgroundColor; }
+  void setBackgroundColor(const Vector4ub& c) { m_backgroundColor = c; }
+
   /**
    * @brief Get or set shadow strength for Ambient Occlusion.
    */
@@ -77,6 +96,9 @@ class SolidPipeline
 private:
   float m_pixelRatio;
   bool m_aoEnabled;
+  Vector4ub m_backgroundColor;
+  Eigen::Affine3f modelView; 
+  bool m_fogEnabled;
   float m_aoStrength;
   bool m_edEnabled;
   float m_edStrength;