Method postProcess

src/renderManager.cpp:376–422

void RenderManager::postProcess(const unsigned int start){
    if(ImGui::CollapsingHeader("Post-processing")){
        ImGui::SliderInt("Blur", &sceneCamera->blurAmount, 0, 10);
        ImGui::SliderFloat("Exposure", &sceneCamera->exposure, 0.1f, 5.0f);
    }

    //TODO:: should be a compute shader 
    pingPongFBO.bind();
    pingPongFBO.clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT, glm::vec3(0.0f));
    if( sceneCamera->blurAmount > 0){
        //Filtering pixel rgb values > 1.0
        highPassFilterShader.use();
        canvas.draw(simpleFBO.texColorBuffer);
    }

    //Applying Gaussian blur in ping pong fashion
    //TODO:: ALso make it a compute shader
    gaussianBlurShader.use();
    for (int i = 0; i < sceneCamera->blurAmount; ++i){
        //Horizontal pass
        glBindFramebuffer(GL_FRAMEBUFFER, simpleFBO.frameBufferID);
        glDrawBuffer(GL_COLOR_ATTACHMENT1);
        gaussianBlurShader.setBool("horizontal", true);
        canvas.draw(pingPongFBO.texColorBuffer);

        //Vertical pass
        glBindFramebuffer(GL_FRAMEBUFFER, pingPongFBO.frameBufferID);
        gaussianBlurShader.setBool("horizontal", false);
        canvas.draw(simpleFBO.blurHighEnd);
    }
    //Setting back to default framebuffer (screen) and clearing
    //No need for depth testing cause we're drawing to a flat quad
    screen->bind();

    //Shader setup for postprocessing
    screenSpaceShader.use();

    screenSpaceShader.setInt("offset", start);
    screenSpaceShader.setFloat("exposure", sceneCamera->exposure);
    screenSpaceShader.setInt("screenTexture", 0);
    screenSpaceShader.setInt("bloomBlur", 1);
    screenSpaceShader.setInt("computeTexture", 2);

    //Merging the blurred high pass image with the low pass values
    //Also tonemapping and doing other post processing
    canvas.draw(simpleFBO.texColorBuffer, pingPongFBO.texColorBuffer);
}