多个错误，在VS2017的头文件中，opengl项目C++
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【中文标题】多个错误，在VS2017的头文件中，opengl项目C++【英文标题】：Multiple errors, in header files in VS2017, opengl project C++ 【发布时间】：2018-03-19 09:41:14 【问题描述】：所以我正在研究来自 learnopengl 的 opengl 项目，而且我是 C++ 的初学者，所以我对它没有什么问题。这是一个VS2017项目。
main.cpp 有问题，当我编译它时显示此错误：
name 后跟 '::' 必须是类或命名空间
它在 (FileSystem::getPath) 中，所以当我在 main.cpp 中包含 filesystem.h 时，它显示另一个错误，但在 filesystem.h 中：无法打开 源文件“root_directory.h”
所以我从https://github.com/alifradityar/LastOrder 下载了root_directory.h 与entry.h 相同。现在我有 10 个警告和 3 个错误 :-) 这就是当人们想要修复一个错误时会发生的情况。
logl_root 未声明的标识符来自filesystem.h 23 next 'getenv': 这个函数或变量可能不安全。考虑改用 _dupenv_s。要禁用弃用，请使用 _CRT_SECURE_NO_WARNINGS。欢迎任何帮助。
我知道我只是初学者，但我应该如何在不尝试处理问题的情况下学习它？而且我知道这个问题有多愚蠢：D...
如果是 7z 中的完整项目，请点击此处： https://drive.google.com/open?id=1vNTkh9HEcMKvM8Yzm0iCTJtx1d2xqvlR
filesystem.h、root_directory.h 和 entry.h 在 /includes/learnopengl lib-s 和 include 在 VS 中链接。
line: 24 - logl_root undefined 23 - 'getenv': 这个函数或 变量可能不安全。考虑改用 _dupenv_s。禁用 弃用，使用 _CRT_SECURE_NO_WARNINGS。欢迎任何帮助。
**filesystem.h**
#ifndef FILESYSTEM_H
#define FILESYSTEM_H
#include <string>
#include <cstdlib>
#include "root_directory.h" // This is a configuration file generated by CMake.
class FileSystem
private:
typedef std::string (*Builder) (const std::string& path);
public:
static std::string getPath(const std::string& path)
static std::string(*pathBuilder)(std::string const &) = getPathBuilder();
return (*pathBuilder)(path);
private:
static std::string const & getRoot()
static char const * envRoot = getenv("LOGL_ROOT_PATH");
static char const * givenRoot = (envRoot != nullptr ? envRoot : logl_root);
static std::string root = (givenRoot != nullptr ? givenRoot : "");
return root;
//static std::string(*foo (std::string const &)) getPathBuilder()
static Builder getPathBuilder()
if (getRoot() != "")
return &FileSystem::getPathRelativeRoot;
else
return &FileSystem::getPathRelativeBinary;
static std::string getPathRelativeRoot(const std::string& path)
return getRoot() + std::string("/") + path;
static std::string getPathRelativeBinary(const std::string& path)
return "../../../" + path;
;
// FILESYSTEM_H
#endif
**root_directory.h**
#ifndef __ROOT
#define __ROOT
#include "entry.h"
#include <iostream>
#include <vector>
#include <string>
#include <ctime>
using namespace std;
class RootDirectory
public:
vector <Entry> data;
RootDirectory();
string toString();
void load(string);
;
#endif#ifndef __ROOT
#define __ROOT
#include "entry.h"
#include <iostream>
#include <vector>
#include <string>
#include <ctime>
using namespace std;
class RootDirectory
public:
vector <Entry> data;
RootDirectory();
string toString();
void load(string);
;
#endif
**main.cpp**
#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <stb_image.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 <learnopengl/filesystem.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);
unsigned int loadTexture(const char *path);
// 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;
// timing
float deltaTime = 0.0f;
float lastFrame = 0.0f;
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);
#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("5.4.light_casters.vs", "5.4.light_casters.fs");
Shader lampShader("5.4.lamp.vs", "5.4.lamp.fs");
// set up vertex data (and buffer(s)) and configure vertex attributes
// ------------------------------------------------------------------
float vertices[] =
// positions // normals // texture coords
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,
0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f,
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
-0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
-0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f,
0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f,
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,
0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f,
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f
;
// positions all containers
glm::vec3 cubePositions[] =
glm::vec3(0.0f, 0.0f, 0.0f),
glm::vec3(2.0f, 5.0f, -15.0f),
glm::vec3(-1.5f, -2.2f, -2.5f),
glm::vec3(-3.8f, -2.0f, -12.3f),
glm::vec3(2.4f, -0.4f, -3.5f),
glm::vec3(-1.7f, 3.0f, -7.5f),
glm::vec3(1.3f, -2.0f, -2.5f),
glm::vec3(1.5f, 2.0f, -2.5f),
glm::vec3(1.5f, 0.2f, -1.5f),
glm::vec3(-1.3f, 1.0f, -1.5f)
;
// 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);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
glEnableVertexAttribArray(1);
glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
glEnableVertexAttribArray(2);
// 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 lightVAO;
glGenVertexArrays(1, &lightVAO);
glBindVertexArray(lightVAO);
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, 8 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
// load textures (we now use a utility function to keep the code more organized)
// -----------------------------------------------------------------------------
unsigned int diffuseMap = loadTexture(FileSystem::getPath("resources/textures/container2.png").c_str());
unsigned int specularMap = loadTexture(FileSystem::getPath("resources/textures/container2_specular.png").c_str());
// shader configuration
// --------------------
lightingShader.use();
lightingShader.setInt("material.diffuse", 0);
lightingShader.setInt("material.specular", 1);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
// per-frame time logic
// --------------------
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);
// be sure to activate shader when setting uniforms/drawing objects
lightingShader.use();
lightingShader.setVec3("light.position", camera.Position);
lightingShader.setVec3("light.direction", camera.Front);
lightingShader.setFloat("light.cutOff", glm::cos(glm::radians(12.5f)));
lightingShader.setFloat("light.outerCutOff", glm::cos(glm::radians(17.5f)));
lightingShader.setVec3("viewPos", camera.Position);
// light properties
lightingShader.setVec3("light.ambient", 0.1f, 0.1f, 0.1f);
// we configure the diffuse intensity slightly higher; the right lighting conditions differ with each lighting method and environment.
// each environment and lighting type requires some tweaking to get the best out of your environment.
lightingShader.setVec3("light.diffuse", 0.8f, 0.8f, 0.8f);
lightingShader.setVec3("light.specular", 1.0f, 1.0f, 1.0f);
lightingShader.setFloat("light.constant", 1.0f);
lightingShader.setFloat("light.linear", 0.09f);
lightingShader.setFloat("light.quadratic", 0.032f);
// material properties
lightingShader.setFloat("material.shininess", 32.0f);
// view/projection transformations
glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
glm::mat4 view = camera.GetViewMatrix();
lightingShader.setMat4("projection", projection);
lightingShader.setMat4("view", view);
// world transformation
glm::mat4 model;
lightingShader.setMat4("model", model);
// bind diffuse map
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, diffuseMap);
// bind specular map
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, specularMap);
// render containers
glBindVertexArray(cubeVAO);
for (unsigned int i = 0; i < 10; i++)
// calculate the model matrix for each object and pass it to shader before drawing
glm::mat4 model;
model = glm::translate(model, cubePositions[i]);
float angle = 20.0f * i;
model = glm::rotate(model, glm::radians(angle), glm::vec3(1.0f, 0.3f, 0.5f));
lightingShader.setMat4("model", model);
glDrawArrays(GL_TRIANGLES, 0, 36);
// again, a lamp object is weird when we only have a spot light, don't render the light object
// lampShader.use();
// lampShader.setMat4("projection", projection);
// lampShader.setMat4("view", view);
// model = glm::mat4();
// model = glm::translate(model, lightPos);
// model = glm::scale(model, glm::vec3(0.2f)); // a smaller cube
// 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);
// 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);
// utility function for loading a 2D texture from file
// ---------------------------------------------------
unsigned int loadTexture(char const * path)
unsigned int textureID;
glGenTextures(1, &textureID);
int width, height, nrComponents;
unsigned char *data = stbi_load(path, &width, &height, &nrComponents, 0);
if (data)
GLenum format;
if (nrComponents == 1)
format = GL_RED;
else if (nrComponents == 3)
format = GL_RGB;
else if (nrComponents == 4)
format = GL_RGBA;
glBindTexture(GL_TEXTURE_2D, textureID);
glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
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);
stbi_image_free(data);
else
std::cout << "Texture failed to load at path: " << path << std::endl;
stbi_image_free(data);
return textureID;
【问题讨论】：
错误消息告诉您如何解决问题。哪一部分你不明白？ 在我看来，#include "root_directory.h" // This is a configuration file generated by CMake. 暗示运行 CMake 来创建项目，而不是尝试下载一些具有匹配名称的文件。
对于_CRT_SECURE_NO_WARNINGS，这是谷歌上的第一击：***.com/questions/16883037/…
CMake 运行应该已经创建了配置目录并包含了它。你有那个文件吗？下载它是最糟糕的主意。
【参考方案1】：
如果有人还在寻找答案...
// FileSystem::getPath(...) 是 GitHub 存储库的一部分，因此我们可以在任何 IDE/平台上找到文件；将其替换为您自己的图像路径。
【讨论】：
【参考方案2】：我将此作为答案而不是评论（尽管我可能应该是评论）。正如你告诉自己你想学习。因此，我不会告诉您“解决方案”，而是会尝试向您展示如何正确处理此类问题的技巧。
首先，处理编译错误时最重要的部分是真正阅读错误信息，然后理解它！ 不要草率下结论，从不相关的来源下载任意文件并将东西混在一起！这种方法行不通！
让我们分解一下。你有一个编译器错误。内容如下：
(…) name followed by '::' must be a class or namespace (…)
不幸的是，您的报价缺少一些信息，即问题发生在哪个文件的哪一行。编译器如何报告错误背后有一定的逻辑。旧版本的 GCC 会吐出相当晦涩的错误日志，通常长达几页；罪魁祸首通常隐藏在整个错误日志的前 5 行左右。通常您可以放心地忽略所有其他内容。
无论如何，它会告诉你哪里出了问题。也就是说，在 C++ 中，如果您编写类似 a::b 的内容，那么 a 必须是 类或命名空间的名称（这正是错误告诉您的内容）。然而，通常类和命名空间是由头文件引入的。如果 include 指令失败，预处理器确实会退出，所以这根本不可能与缺少的 include 有任何关系。
但也可能发生的是，before 包含某些东西不是它应该的样子。通常缺少分号 (;)。这可能会导致类声明与其他内容混淆。
因此，您应该这样做：从头开始仔细重新阅读编译器日志。查看顶部的所有警告和错误，然后继续往下看。
如果您再次遇到困难，编辑您的问题，如果我可以帮助您，我会附加到这个答案。
【讨论】：
感谢您的回复，现在我意识到我应该以其他方式解决这个问题，对于我仅用于实现库和包含的 cmake 也是如此。以上是关于多个错误，在VS2017的头文件中，opengl项目C++的主要内容，如果未能解决你的问题，请参考以下文章