[add]: add bloom and blur

3 files changed, 45 insertions, 2 deletions

diff --git a/src/Engine/Engine.cpp b/src/Engine/Engine.cpp
index 37cafd8..20a295f 100644
--- a/src/Engine/Engine.cpp
+++ b/src/Engine/Engine.cpp
@@ -34,6 +34,7 @@ namespace Donut
 
         m_ShaderProgram  = Ref<Shader>(Shader::Create("Assets/Shaders/ComputeTextureQuad.glsl"));
         m_ComputeProgram = CreateComputeProgram("Assets/Shaders/Geodesic.glsl");
+        m_BlurShader     = Ref<Shader>(Shader::Create("Assets/Shaders/Blur.glsl"));
         
         m_CameraUBO = UniformBuffer::Create(128, 1);
         m_DiskUBO   = UniformBuffer::Create(sizeof(float) * 5, 2);  // Added density parameter
@@ -96,6 +97,24 @@ namespace Donut
         RenderCommand::EnableDepthTest();
     }
 
+    void Engine::DrawBlurPass()
+    {
+        RenderCommand::SetViewport(0, 0, m_Width, m_Height);
+        
+        m_BlurShader->Bind();
+        m_QuadVAO->Bind();
+
+        m_Texture->Bind(0);
+        m_BlurShader->SetInt("u_ScreenTexture", 0);
+        m_BlurShader->SetFloat2("u_Resolution", glm::vec2(m_Width, m_Height));
+        m_BlurShader->SetFloat("u_BlurStrength", m_BlurStrength);
+        m_BlurShader->SetFloat("u_GlowIntensity", m_GlowIntensity);
+
+        RenderCommand::DisableDepthTest();
+        RenderCommand::DrawArrays(6);
+        RenderCommand::EnableDepthTest();
+    }
+
     void Engine::DispatchCompute(const Camera& cam)
     {
         int cw = GetComputeWidth();
diff --git a/src/Engine/Engine.h b/src/Engine/Engine.h
index a0b25b5..83f0b19 100644
--- a/src/Engine/Engine.h
+++ b/src/Engine/Engine.h
@@ -66,6 +66,7 @@ namespace Donut
         ~Engine() = default;
 
         void DrawFullScreenQuad();
+        void DrawBlurPass();
         void DispatchCompute(const Camera& cam);
         void UploadCameraUBO(const Camera& cam);
         void UploadObjectsUBO(const std::vector<ObjectData>& objs);
@@ -109,6 +110,12 @@ namespace Donut
         float GetRotationSpeed() const { return m_RotationSpeed; }
         void  SetRotationSpeed(float speed) { m_RotationSpeed = speed; }
         
+        float GetBlurStrength() const { return m_BlurStrength; }
+        void  SetBlurStrength(float strength) { m_BlurStrength = strength; }
+        
+        float GetGlowIntensity() const { return m_GlowIntensity; }
+        void  SetGlowIntensity(float intensity) { m_GlowIntensity = intensity; }
+        
         void LoadObjectsFromScene(const std::vector<Donut::Object>& objects);
         void ExportHighResFrame(const std::string& filename, int width = 4096, int height = 3072);
         void PrintObjectInfo() const;
@@ -120,6 +127,7 @@ namespace Donut
         Ref<Texture2D>     m_Texture;
         Ref<Shader>        m_ShaderProgram;
         Ref<Shader>        m_ComputeProgram;
+        Ref<Shader>        m_BlurShader;
         Ref<UniformBuffer> m_CameraUBO;
         Ref<UniformBuffer> m_DiskUBO;
         Ref<UniformBuffer> m_ObjectsUBO;
@@ -145,7 +153,9 @@ namespace Donut
         float m_EarlyExitDistance = 5e11f;
         
         float m_DiskThickness = 0.1;    
-        float m_DiskDensity   = 1.2f;
+        float m_DiskDensity   = 0.1f;
         float m_RotationSpeed = 1.0f;
+        float m_BlurStrength  = 2.0f;
+        float m_GlowIntensity = 0.1f;
     };
 };
diff --git a/src/States/SimulationState.cpp b/src/States/SimulationState.cpp
index 28504e6..2a79b3c 100644
--- a/src/States/SimulationState.cpp
+++ b/src/States/SimulationState.cpp
@@ -60,7 +60,7 @@ namespace Donut
         RenderCommand::SetViewport(0, 0, static_cast<uint32_t>(engine.GetWidth()), static_cast<uint32_t>(engine.GetHeight()));
 
         engine.DispatchCompute(engine.GetCamera());
-        engine.DrawFullScreenQuad();
+        engine.DrawBlurPass();
     }
     
     void SimulationState::OnEvent(Event& event)
@@ -244,6 +244,20 @@ namespace Donut
         }
         ImGui::TextDisabled("Rotation speed multiplier (0 = no rotation)");
         
+        float blurStrength = engine.GetBlurStrength();
+        if (ImGui::SliderFloat("Blur Strength", &blurStrength, 0.5f, 5.0f, "%.2f"))
+        {
+            engine.SetBlurStrength(blurStrength);
+        }
+        ImGui::TextDisabled("Blur radius for glow effect");
+        
+        float glowIntensity = engine.GetGlowIntensity();
+        if (ImGui::SliderFloat("Glow Intensity", &glowIntensity, 0.1f, 3.0f, "%.2f"))
+        {
+            engine.SetGlowIntensity(glowIntensity);
+        }
+        ImGui::TextDisabled("Intensity of the glow effect");
+        
         ImGui::Spacing();
         
         ImGui::TextColored(ImVec4(0.9f, 0.9f, 1.0f, 1.0f), "Camera");