antialiasing copypasta job xd

src/main.cpp

@@ -77,7 +77,7 @@ class Cubemap {
             }
         }
         
-        glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+        glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST_MIPMAP_LINEAR);
         glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
         glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
@@ -129,9 +129,6 @@ class SDLGLGLWindow {
     unsigned int instance_VBO;
     unsigned int lightVAO;
     unsigned int quadVAO;
-    unsigned int framebuffer;
-    unsigned int texColourBuffer;
-    unsigned int rbo;
     unsigned int texture[2];
     unsigned int cubemap;
 
@@ -164,6 +161,11 @@ class SDLGLGLWindow {
     public:
     int screen_width;
     int screen_height;
+    unsigned int framebuffer;
+    unsigned int textureColorBufferMultiSampled;
+    unsigned int rbo;
+    unsigned int intermediateFBO;
+    unsigned int screenTexture;
     SDL_Window *gWindow;
 
     glm::vec3 camera_pos = glm::vec3(0.0f, 0.0f, 3.0f);
@@ -217,6 +219,7 @@ class SDLGLGLWindow {
         gWindow = SDL_CreateWindow( "SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, 
                 SDL_WINDOWPOS_UNDEFINED, screen_width, screen_height, 
                 SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
+
         
         auto gContext = SDL_GL_CreateContext( gWindow );
         if( gContext == NULL ) {
@@ -239,12 +242,26 @@ class SDLGLGLWindow {
                 << SDL_GetError() << std::endl;
         }
 
+//        SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, 2);
+        std::cerr <<  "Creating msbuffers" 
+            << SDL_GetError() << std::endl ;
+ //       SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, 2);
+        std::cerr <<  "Creating msbuffers" 
+            << SDL_GetError() << std::endl ;
+
         //Initialize OpenGL
         if( !initGL() )
         {
             std::cerr << "Unable to initialie OpenGL!" << std::endl;
             return false;
         }
+
+
+
+        glEnable(GL_MULTISAMPLE);
+        glGetError();
+
+
         return true;
     }
 
@@ -267,8 +284,7 @@ class SDLGLGLWindow {
         view = glm::translate(view, glm::vec3(0.0f, 0.0f, -3.0f));
         projection = glm::perspective(glm::radians(45.0f), 800.0f / 600.0f, 0.1f, 100.0f);
 
-
-        /* generate a framebuffer to draw to */
+        /* generate a framebuffer to draw to 
         glGenFramebuffers(1, &framebuffer);
         glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
 
@@ -294,6 +310,43 @@ class SDLGLGLWindow {
         glBindFramebuffer(GL_FRAMEBUFFER, 0); // unbind
         glCheckError();
 
+        */
+
+        /* MSAA FRAMEBUFFERS */
+
+        glGenFramebuffers(1, &framebuffer);
+        glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
+        // create a multisampled color attachment texture
+        glGenTextures(1, &textureColorBufferMultiSampled);
+        glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, textureColorBufferMultiSampled);
+        glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, 4, GL_RGB, screen_width, screen_height, GL_TRUE);
+        glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, 0);
+        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D_MULTISAMPLE, textureColorBufferMultiSampled, 0);
+        // create a (also multisampled) renderbuffer object for depth and stencil attachments
+        glGenRenderbuffers(1, &rbo);
+        glBindRenderbuffer(GL_RENDERBUFFER, rbo);
+        glRenderbufferStorageMultisample(GL_RENDERBUFFER, 4, GL_DEPTH24_STENCIL8, screen_width, screen_height);
+        glBindRenderbuffer(GL_RENDERBUFFER, 0);
+        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, rbo);
+
+        if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+            std::cout << "ERROR::FRAMEBUFFER:: Framebuffer is not complete!" << std::endl;
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+        // configure second post-processing framebuffer
+        glGenFramebuffers(1, &intermediateFBO);
+        glBindFramebuffer(GL_FRAMEBUFFER, intermediateFBO);
+        // create a color attachment texture
+        glGenTextures(1, &screenTexture);
+        glBindTexture(GL_TEXTURE_2D, screenTexture);
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, screen_width, screen_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);
+        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, screenTexture, 0);	// we only need a color buffer
+
+        if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+            std::cout << "ERROR::FRAMEBUFFER:: Intermediate framebuffer is not complete!" << std::endl;
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
         std::default_random_engine generator;
         std::uniform_real_distribution<float> distribution(-50,50);
@@ -302,9 +355,10 @@ class SDLGLGLWindow {
             float x = distribution(generator) ;
             float y = distribution(generator) ;
             float z = distribution(generator) ;
-            translations[i] = glm::vec3(i,y,z);
+            translations[i] = glm::vec3(x,y,z);
         }
 
+        glCheckError();
         shader->use();
 
         glGenBuffers(1, &instance_VBO);
@@ -537,11 +591,13 @@ class SDLGLGLWindow {
     {
 
         glCheckError();
+
         glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
         glEnable(GL_DEPTH_TEST);
         glCheckError();
 
 
+
         view = glm::lookAt(camera_pos, camera_pos + camera_front, camera_up);
 
         //Clear color buffer
@@ -746,31 +802,33 @@ class SDLGLGLWindow {
         glDrawArrays(GL_TRIANGLES, 0, 36);
         glCheckError();
 
-        glCheckError();
 
         printProgramLog(skyboxShader->program);
 
 
-
-
-
-
+        // 2. now blit multisampled buffer(s) to normal colorbuffer of intermediate FBO. Image is stored in screenTexture
+        glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffer);
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, intermediateFBO);
+        glBlitFramebuffer(0, 0, screen_width, screen_height, 0, 0, screen_width, screen_height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
 
 
         glCheckError();
 
-
         glBindFramebuffer(GL_FRAMEBUFFER, 0);
+        glClearColor(1.0,1.0,1.0,1.0);
         glClear(GL_COLOR_BUFFER_BIT);
+        glDisable(GL_DEPTH_TEST);
+
+        //glPolygonMode( GL_FRONT_AND_BACK, GL_FILL);
 
         texShader->use();
-        glPolygonMode( GL_FRONT_AND_BACK, GL_FILL);
         glBindVertexArray(quadVAO);
 
-        glDisable(GL_DEPTH_TEST);
-        glBindTexture(GL_TEXTURE_2D, texColourBuffer);
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, screenTexture);
         glDrawArrays(GL_TRIANGLES, 0, 6);
 
+        printProgramLog(texShader->program);
         glCheckError();
 
     }
@@ -813,6 +871,7 @@ int main(int argc, char **argv) {
     SDL_SetRelativeMouseMode(SDL_TRUE);
     bool mouse_mode = true;
 
+    std::cout << "Rendering now\n";
     //While application is running
     while( !quit )
     {