Code Viewer. Source code: advanced-lighting/blinn

// Std. Includes
#include <string>

// GLEW
#define GLEW_STATIC
#include <GL/glew.h>

// GLFW
#include <GLFW/glfw3.h>

// GL includes
#include <learnopengl/shader.h>
#include <learnopengl/camera.h>

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

// Other Libs
#include <SOIL.h>

// Properties
const GLuint SCR_WIDTH = 800, SCR_HEIGHT = 600;

// Function prototypes
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void Do_Movement();
GLuint loadTexture(GLchar* path);

// Camera
Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));

// Delta
GLfloat deltaTime = 0.0f;
GLfloat lastFrame = 0.0f;

// Options
GLboolean blinn = false;

// The MAIN function, from here we start our application and run our Game loop
int main()
{
    // Init GLFW
    glfwInit();
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
    glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);

    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", nullptr, nullptr); // Windowed
    glfwMakeContextCurrent(window);

    // Set the required callback functions
    glfwSetKeyCallback(window, key_callback);
    glfwSetCursorPosCallback(window, mouse_callback);
    glfwSetScrollCallback(window, scroll_callback);

    // Options
    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);

    // Initialize GLEW to setup the OpenGL Function pointers
    glewExperimental = GL_TRUE;
    glewInit();

    // Define the viewport dimensions
    glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);

    // Setup some OpenGL options
    glEnable(GL_DEPTH_TEST);
    // glDepthFunc(GL_ALWAYS); // Set to always pass the depth test (same effect as glDisable(GL_DEPTH_TEST))

    // Setup and compile our shaders
    Shader shader("advanced_lighting.vs", "advanced_lighting.frag");

    GLfloat planeVertices[] = {
        // Positions          // Normals         // Texture Coords
         8.0f, -0.5f,  8.0f,  0.0f, 1.0f, 0.0f,  5.0f, 0.0f,
        -8.0f, -0.5f,  8.0f,  0.0f, 1.0f, 0.0f,  0.0f, 0.0f,
        -8.0f, -0.5f, -8.0f,  0.0f, 1.0f, 0.0f,  0.0f, 5.0f,

         8.0f, -0.5f,  8.0f,  0.0f, 1.0f, 0.0f,  5.0f, 0.0f,
        -8.0f, -0.5f, -8.0f,  0.0f, 1.0f, 0.0f,  0.0f, 5.0f,
         8.0f, -0.5f, -8.0f,  0.0f, 1.0f, 0.0f,  5.0f, 5.0f
    };
    // Setup plane VAO
    GLuint planeVAO, planeVBO;
    glGenVertexArrays(1, &planeVAO);
    glGenBuffers(1, &planeVBO);
    glBindVertexArray(planeVAO);
    glBindBuffer(GL_ARRAY_BUFFER, planeVBO);
    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);
    glEnableVertexAttribArray(0);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
    glEnableVertexAttribArray(1);
    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
    glEnableVertexAttribArray(2);
    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
    glBindVertexArray(0);

    // Light source
    glm::vec3 lightPos(0.0f, 0.0f, 0.0f);

    // Load textures
    GLuint floorTexture = loadTexture("../../../resources/textures/wood.png");

    // Game loop
    while(!glfwWindowShouldClose(window))
    {
        // Set frame time
        GLfloat currentFrame = glfwGetTime();
        deltaTime = currentFrame - lastFrame;
        lastFrame = currentFrame;

        // Check and call events
        glfwPollEvents();
        Do_Movement();

        // Clear the colorbuffer
        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        // Draw objects
        shader.Use(); 
        glm::mat4 view = camera.GetViewMatrix();
        glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "view"), 1, GL_FALSE, glm::value_ptr(view));
        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "projection"), 1, GL_FALSE, glm::value_ptr(projection));
        // Set light uniforms
        glUniform3fv(glGetUniformLocation(shader.Program, "lightPos"), 1, &lightPos[0]);
        glUniform3fv(glGetUniformLocation(shader.Program, "viewPos"), 1, &camera.Position[0]);
        glUniform1i(glGetUniformLocation(shader.Program, "blinn"), blinn);
        // Floor
        glBindVertexArray(planeVAO);
        glBindTexture(GL_TEXTURE_2D, floorTexture);
        glDrawArrays(GL_TRIANGLES, 0, 6);
        glBindVertexArray(0);				

        std::cout << (blinn ? "true" : "false") << std::endl;

        // Swap the buffers
        glfwSwapBuffers(window);
    }

    glfwTerminate();
    return 0;
}

// This function loads a texture from file. Note: texture loading functions like these are usually 
// managed by a 'Resource Manager' that manages all resources (like textures, models, audio). 
// For learning purposes we'll just define it as a utility function.
GLuint loadTexture(GLchar* path)
{
    // Generate texture ID and load texture data 
    GLuint textureID;
    glGenTextures(1, &textureID);
    int width,height;
    unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);
    // Assign texture to ID
    glBindTexture(GL_TEXTURE_2D, textureID);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
    glGenerateMipmap(GL_TEXTURE_2D);	

    // Parameters
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR );
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glBindTexture(GL_TEXTURE_2D, 0);
    SOIL_free_image_data(image);
    return textureID;

}

bool keys[1024];
bool keysPressed[1024];
// Moves/alters the camera positions based on user input
void Do_Movement()
{
    // Camera controls
    if(keys[GLFW_KEY_W])
        camera.ProcessKeyboard(FORWARD, deltaTime);
    if(keys[GLFW_KEY_S])
        camera.ProcessKeyboard(BACKWARD, deltaTime);
    if(keys[GLFW_KEY_A])
        camera.ProcessKeyboard(LEFT, deltaTime);
    if(keys[GLFW_KEY_D])
        camera.ProcessKeyboard(RIGHT, deltaTime);

    if (keys[GLFW_KEY_B] && !keysPressed[GLFW_KEY_B])
    {
        blinn = !blinn;
        keysPressed[GLFW_KEY_B] = true;
    }
}

GLfloat lastX = 400, lastY = 300;
bool firstMouse = true;
// Is called whenever a key is pressed/released via GLFW
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
{
    if(key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
        glfwSetWindowShouldClose(window, GL_TRUE);

    if (key >= 0 && key <= 1024)
    {
        if (action == GLFW_PRESS)
            keys[key] = true;
        else if (action == GLFW_RELEASE)
        {
            keys[key] = false;
            keysPressed[key] = false;
        }
    }
}

void mouse_callback(GLFWwindow* window, double xpos, double ypos)
{
    if(firstMouse)
    {
        lastX = xpos;
        lastY = ypos;
        firstMouse = false;
    }

    GLfloat xoffset = xpos - lastX;
    GLfloat yoffset = lastY - ypos; 
    
    lastX = xpos;
    lastY = ypos;

    camera.ProcessMouseMovement(xoffset, yoffset);
}	

void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
    camera.ProcessMouseScroll(yoffset);
}