Materials_练习

你能像教程一开始那样，定义相应的材质来模拟现实世界的物体吗？

分享一个银材质的箱子：

// silver material
lightingShader.setVec3("material.ambient", 0.19225,0.19225,0.19225);
lightingShader.setVec3("material.diffuse", 0.50754 ,0.50754, 0.50754);
lightingShader.setVec3("material.specular", 0.508273, 0.508273 ,0.508273);
lightingShader.setFloat("material.shininess", 0.4 * 128);

完整代码：

#include <glad/glad.h>
#include <GLFW/glfw3.h>
#define STB_IMAGE_IMPLEMENTATION
#include <stb/stb_image.h>

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

#include <Shader/shader.h>
#include <Camera/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(0.0f, 0.0f, 3.0f));
float lastX = SCR_WIDTH / 2.0f;
float lastY = SCR_HEIGHT / 2.0f;
bool firstMouse = true;

//timeing
float deltaTime = 0.0f; // 当前帧与上一帧的时间差
float lastFrame = 0.0f; // 上一帧的时间

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

int main()
{
    // glfw: initialize and configure
    // ------------------------------
    glfwInit();
    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); // uncomment this statement to fix compilation on OS X
#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();
        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("colors.vs", "colors.fs");
    Shader lampShader("lamp.vs", "lamp.fs");

    // set up vertex data (and buffer(s)) and configure vertex attributes
    // ------------------------------------------------------------------
    float vertices[] = {
        -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
        0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
        0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
        0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
        -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
        -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,

        -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
        0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
        0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
        0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
        -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
        -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,

        -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f,
        -0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
        -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
        -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
        -0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f,
        -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f,

        0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
        0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
        0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
        0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
        0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
        0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f,

        -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,
        0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,
        0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
        0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
        -0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
        -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,

        -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f,
        0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f,
        0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
        0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
        -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
        -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f
    };

    unsigned int VBO, cubeVAO;
    glGenVertexArrays(1, &cubeVAO);
    glGenBuffers(1, &VBO);

    glBindVertexArray(cubeVAO);

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

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

    unsigned int lightVAO;
    glGenVertexArrays(1, &lightVAO);
    glBindVertexArray(lightVAO);
    // 只需要绑定VBO不用再次设置VBO的数据，因为箱子的VBO数据中已经包含了正确的立方体顶点数据
    glBindBuffer(GL_ARRAY_BUFFER, VBO);
    // 设置灯立方体的顶点属性（对我们的灯来说仅仅只有位置数据）
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
    glEnableVertexAttribArray(0);

    // pass projection matrix to shader (as projection matrix rarely changes there's no need to do this per frame)
    // -----------------------------------------------------------------------------------------------------------
    //glm::mat4 projection = glm::perspective(glm::radians(45.0f), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
    //ourShader.setMat4("projection", projection);

    // render loop
    // -----------
    while (!glfwWindowShouldClose(window))
    {
        float currentFrame = glfwGetTime();
        deltaTime = currentFrame - lastFrame;
        lastFrame = currentFrame;

        // input
        // -----
        processInput(window);

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

        // activate shader
        lightingShader.use();
        lightingShader.setVec3("objectColor", 1.0f, 0.5f, 0.31f);
        lightingShader.setVec3("lightColor", 1.0f, 1.0f, 1.0f);
        lightingShader.setVec3("lightPos", lightPos);
        lightingShader.setVec3("viewPos", camera.Position);

        //lightingShader.setVec3("material.ambient", 1.0f, 0.5f, 0.31f);
        //lightingShader.setVec3("material.diffuse", 1.0f, 0.5f, 0.31f);
        //lightingShader.setVec3("material.specular", 0.5f, 0.5f, 0.5f);
        //lightingShader.setFloat("material.shininess", 32.0f);
        lightingShader.setVec3("material.ambient", 0.19225, 0.19225, 0.19225);
        lightingShader.setVec3("material.diffuse", 0.50754, 0.50754, 0.50754);
        lightingShader.setVec3("material.specular", 0.508273, 0.508273, 0.508273);
        lightingShader.setFloat("material.shininess", 0.4 * 128);

        lightingShader.setVec3("light.ambient", 0.2f, 0.2f, 0.2f);
        lightingShader.setVec3("light.diffuse", 0.5f, 0.5f, 0.5f); // 将光照调暗了一些以搭配场景
        /*
        glm::vec3 lightColor;
        lightColor.x = sin(glfwGetTime() * 2.0f);
        lightColor.y = sin(glfwGetTime() * 0.7f);
        lightColor.z = sin(glfwGetTime() * 1.3f);

        glm::vec3 diffuseColor = lightColor   * glm::vec3(0.5f); // 降低影响
        glm::vec3 ambientColor = diffuseColor * glm::vec3(0.2f); // 很低的影响

        lightingShader.setVec3("light.ambient", ambientColor);
        lightingShader.setVec3("light.diffuse", diffuseColor);
        */
        lightingShader.setVec3("light.specular", 1.0f, 1.0f, 1.0f);

        // pass projection matrix to shader (note that in this case it could change every frame)
        glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
        lightingShader.setMat4("projection", projection);

        // camera/view transformation
        glm::mat4 view = camera.GetViewMatrix();
        lightingShader.setMat4("view", view);

        glm::mat4 model = glm::mat4(1.0);
        lightingShader.setMat4("model", model);
        // render boxes
        glBindVertexArray(cubeVAO);
        glDrawArrays(GL_TRIANGLES, 0, 36);

        lampShader.use();
        lampShader.setMat4("projection", projection);
        lampShader.setMat4("view", view);
        model = glm::mat4(1.0f);
        float r = 5.0f;
        float x = sin(glfwGetTime())*r;
        float z = cos(glfwGetTime())*r;
        lightPos.x = x; lightPos.z = z;
        model = glm::translate(model, lightPos);
        model = glm::scale(model, glm::vec3(0.2f));
        lampShader.setMat4("model", model);

        glBindVertexArray(lightVAO);
        glDrawArrays(GL_TRIANGLES, 0, 36);

        // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
        // -------------------------------------------------------------------------------
        glfwSwapBuffers(window);
        glfwPollEvents();
    }

    // optional: de-allocate all resources once they've outlived their purpose:
    // ------------------------------------------------------------------------
    glDeleteVertexArrays(1, &cubeVAO);
    glDeleteVertexArrays(1, &lightVAO);
    glDeleteBuffers(1, &VBO);

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

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;
    //std::cout << ypos << std::endl;
    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);
}

2019/11/30