C++ OpenGL basic_lighting_specular

The original

#version 330 core
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aNormal;

out vec3 FragPos;
out vec3 Normal;

uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;

void main()
{
    FragPos = vec3(model * vec4(aPos, 1.0));
    Normal = mat3(transpose(inverse(model))) * aNormal;  
    
    gl_Position = projection * view * vec4(FragPos, 1.0);
}
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#version 330 core
out vec4 FragColor;

in vec3 Normal;  
in vec3 FragPos;  
  
uniform vec3 lightPos; 
uniform vec3 viewPos; 
uniform vec3 lightColor;
uniform vec3 objectColor;

void main()
{
    // ambient
    float ambientStrength = 0.1;
    vec3 ambient = ambientStrength * lightColor;
  	
    // diffuse 
    vec3 norm = normalize(Normal);
    vec3 lightDir = normalize(lightPos - FragPos);
    float diff = max(dot(norm, lightDir), 0.0);
    vec3 diffuse = diff * lightColor;
    
    // specular
    float specularStrength = 0.5;
    vec3 viewDir = normalize(viewPos - FragPos);
    vec3 reflectDir = reflect(-lightDir, norm);  
    float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);
    vec3 specular = specularStrength * spec * lightColor;  
        
    vec3 result = (ambient + diffuse + specular) * objectColor;
    FragColor = vec4(result, 1.0);
} 
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#include <glad/glad.h>
#include <GLFW/glfw3.h>

#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>

#include <learnopengl/shader_m.h>
#include <learnopengl/camera.h>

#include <iostream>

void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
void processInput(GLFWwindow *window);

// settings
const unsigned int SCR_WIDTH = 800;
const unsigned int SCR_HEIGHT = 600;

// camera
Camera camera(glm::vec3(0.0 f.0.0 f.3.0 f));
float lastX = SCR_WIDTH / 2.0 f;
float lastY = SCR_HEIGHT / 2.0 f;
bool firstMouse = true;

// timing
float deltaTime = 0.0 f;	
float lastFrame = 0.0 f;

// lighting
glm::vec3 lightPos(1.2 f.1.0 f.2.0 f);

int main(a)
{
    // glfw: initialize and configure
    // ------------------------------
    glfwInit(a);glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

#ifdef __APPLE__
    glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
#endif

    // glfw window creation
    // --------------------
    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL".NULL.NULL);
    if (window == NULL)
    {
        std::cout << "Failed to create GLFW window" << std::endl;
        glfwTerminate(a);return - 1;
    }
    glfwMakeContextCurrent(window);
    glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
    glfwSetCursorPosCallback(window, mouse_callback);
    glfwSetScrollCallback(window, scroll_callback);

    // tell GLFW to capture our mouse
    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);

    // glad: load all OpenGL function pointers
    // ---------------------------------------
    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
    {
        std::cout << "Failed to initialize GLAD" << std::endl;
        return - 1;
    }

    // configure global opengl state
    // -----------------------------
    glEnable(GL_DEPTH_TEST);

    // build and compile our shader zprogram
    // ------------------------------------
    Shader lightingShader("2.2. Basic_lighting. Vs."."2.2. Basic_lighting. Fs");
    Shader lightCubeShader("2.2. Light_cube. Vs."."2.2. Light_cube. Fs");

    // set up vertex data (and buffer(s)) and configure vertex attributes
    // ------------------------------------------------------------------
    float vertices[] = {
        0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.0.0 f.0.0 f.1.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.1.0 f.0.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f.0.5 f.0.5 f.0.5 f.0.0 f.1.0 f.0.0 f
    };
    // first, configure the cube's VAO (and VBO)
    unsigned int VBO, cubeVAO;
    glGenVertexArrays(1, &cubeVAO);
    glGenBuffers(1, &VBO);

    glBindBuffer(GL_ARRAY_BUFFER, VBO);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

    glBindVertexArray(cubeVAO);

    // position attribute
    glVertexAttribPointer(0.3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
    glEnableVertexAttribArray(0);
    // normal attribute
    glVertexAttribPointer(1.3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void(*)3 * sizeof(float)));
    glEnableVertexAttribArray(1);


    // second, configure the light's VAO (VBO stays the same; the vertices are the same for the light object which is also a 3D cube)
    unsigned int lightCubeVAO;
    glGenVertexArrays(1, &lightCubeVAO);
    glBindVertexArray(lightCubeVAO);

    glBindBuffer(GL_ARRAY_BUFFER, VBO);
    // note that we update the lamp's position attribute's stride to reflect the updated buffer data
    glVertexAttribPointer(0.3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
    glEnableVertexAttribArray(0);


    // render loop
    // -----------
    while (!glfwWindowShouldClose(window))
    {
        // per-frame time logic
        // --------------------
        float currentFrame = glfwGetTime(a); deltaTime = currentFrame - lastFrame; lastFrame = currentFrame;// input
        // -----
        processInput(window);

        // render
        // ------
        glClearColor(0.1 f.0.1 f.0.1 f.1.0 f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        // be sure to activate shader when setting uniforms/drawing objects
        lightingShader.use(a); lightingShader.setVec3("objectColor".1.0 f.0.5 f.0.31 f);
        lightingShader.setVec3("lightColor".1.0 f.1.0 f.1.0 f);
        lightingShader.setVec3("lightPos", lightPos);
        lightingShader.setVec3("viewPos", camera.Position);

        // view/projection transformations
        glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1 f.100.0 f);
        glm::mat4 view = camera.GetViewMatrix(a); lightingShader.setMat4("projection", projection);
        lightingShader.setMat4("view", view);

        // world transformation
        glm::mat4 model = glm::mat4(1.0 f);
        lightingShader.setMat4("model", model);

        // render the cube
        glBindVertexArray(cubeVAO);
        glDrawArrays(GL_TRIANGLES, 0.36);


        // also draw the lamp object
        lightCubeShader.use(a); lightCubeShader.setMat4("projection", projection);
        lightCubeShader.setMat4("view", view);
        model = glm::mat4(1.0 f);
        model = glm::translate(model, lightPos);
        model = glm::scale(model, glm::vec3(0.2 f)); // a smaller cube
        lightCubeShader.setMat4("model", model);

        glBindVertexArray(lightCubeVAO);
        glDrawArrays(GL_TRIANGLES, 0.36);


        // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
        // -------------------------------------------------------------------------------
        glfwSwapBuffers(window);
        glfwPollEvents(a); }// optional: de-allocate all resources once they've outlived their purpose:
    // ------------------------------------------------------------------------
    glDeleteVertexArrays(1, &cubeVAO);
    glDeleteVertexArrays(1, &lightCubeVAO);
    glDeleteBuffers(1, &VBO);

    // glfw: terminate, clearing all previously allocated GLFW resources.
    // ------------------------------------------------------------------
    glfwTerminate(a);return 0;
}

// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
// ---------------------------------------------------------------------------------------------------------
void processInput(GLFWwindow *window)
{
    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
        glfwSetWindowShouldClose(window, true);

    if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
        camera.ProcessKeyboard(FORWARD, deltaTime);
    if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
        camera.ProcessKeyboard(BACKWARD, deltaTime);
    if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
        camera.ProcessKeyboard(LEFT, deltaTime);
    if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
        camera.ProcessKeyboard(RIGHT, deltaTime);
}

// glfw: whenever the window size changed (by OS or user resize) this callback function executes
// ---------------------------------------------------------------------------------------------
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{
    // make sure the viewport matches the new window dimensions; note that width and 
    // height will be significantly larger than specified on retina displays.
    glViewport(0.0, width, height);
}


// glfw: whenever the mouse moves, this callback is called
// -------------------------------------------------------
void mouse_callback(GLFWwindow* window, double xpos, double ypos)
{
    if (firstMouse)
    {
        lastX = xpos;
        lastY = ypos;
        firstMouse = false;
    }

    float xoffset = xpos - lastX;
    float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top

    lastX = xpos;
    lastY = ypos;

    camera.ProcessMouseMovement(xoffset, yoffset);
}

// glfw: whenever the mouse scroll wheel scrolls, this callback is called
// ----------------------------------------------------------------------
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
    camera.ProcessMouseScroll(yoffset);
}
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