Question

我正在尝试在Linux中设置一个使用OpenGL 3.2核心配置文件和GLEW的非常基本的程序。我在article的帮助下尝试了这一点。

这是我的代码：

#define GLEW_STATIC
#include <iostream>
#include <cstdio>
#include <string>
#include <GL/glew.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <GL/gl.h>
#include <GL/glx.h>

//#include <GL/glut.h>
#include "stb_image_write.h"
#include <cstdlib>
#include <GL/glfw.h>


static float _viewPortHeight = 30;
static float _viewPortWidth = 10;

typedef GLXContext (*glXCreateContextAttribsARBProc)(Display*, GLXFBConfig, GLXContext, Bool, const int*);
typedef Bool (*glXMakeContextCurrentARBProc)(Display*, GLXDrawable, GLXDrawable, GLXContext);
static glXCreateContextAttribsARBProc glXCreateContextAttribsARB = NULL;
static glXMakeContextCurrentARBProc   glXMakeContextCurrentARB   = NULL;

int main (int argc, char *argv[]){
    glXCreateContextAttribsARB = (glXCreateContextAttribsARBProc) glXGetProcAddressARB( (const GLubyte *) "glXCreateContextAttribsARB" );
    glXMakeContextCurrentARB   = (glXMakeContextCurrentARBProc)   glXGetProcAddressARB( (const GLubyte *) "glXMakeContextCurrent");
    Display *display = XOpenDisplay(NULL);
    if (display == NULL){
        std::cout  << "error getting the X display";
        return -1;
     }

    static int visualAttribs[] = {None};
    int numberOfFrameBufferConfigurations;
    GLXFBConfig *fbConfigs = glXChooseFBConfig(display, DefaultScreen(display), visualAttribs, &numberOfFrameBufferConfigurations);

     int context_attribs[] = {
          GLX_CONTEXT_MAJOR_VERSION_ARB ,3,
          GLX_CONTEXT_MINOR_VERSION_ARB, 2,
          GLX_CONTEXT_FLAGS_ARB, GLX_CONTEXT_DEBUG_BIT_ARB,
          GLX_CONTEXT_PROFILE_MASK_ARB, GLX_CONTEXT_CORE_PROFILE_BIT_ARB,None
     };

    std::cout << "initialising context...";
    GLXContext openGLContext = glXCreateContextAttribsARB(display, fbConfigs[0], 0, True, context_attribs);

    int pBufferAttribs[] = {
        GLX_PBUFFER_WIDTH, 32,
        GLX_PBUFFER_HEIGHT, 32,
        None
    };

    GLXPbuffer pbuffer = glXCreatePbuffer(display, fbConfigs[0], pBufferAttribs);
    XFree(fbConfigs);
    XSync(display, False);
    if(!glXMakeContextCurrent(display, pbuffer, pbuffer, openGLContext)){
        std::cout << "error with content creation";
        return -1;
    }
    glXMakeCurrent(display, pbuffer, openGLContext);

    GLenum error = glewInit();
    if (error != GLEW_OK){
       std::cout << "error with glew init()\n";
    }else{
        std::cout << "glew is ok\n\n";
    }
    GLuint test;
    GLuint framebuffer;
    glGenFramebuffers(1, &framebuffer);

    glClearColor(1.0f, 0.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    std::string path("output.png");
    exportToPath(path);

    return 0;
 }

我得到的输出是：

初始化上下文...... glew没问题

分段错误（核心转储）

导致问题的行是glGenFrameBuffers调用，这也是对GLEW生成的函数的第一次调用。这里有些不对劲，但我似乎无法弄清楚是什么以及为什么。

有人能指出我正确的方向吗？

Answer 1

glew.h已包含gl.h且GLX可用glx.h ...然后使用一些宏魔术来弯曲某些符号。我建议你删除这些行

#include <GL/gl.h>
#include <GL/glx.h>

然后使用

#include <GL/glew.h>

在GLEW包含原始包含后，一些宏魔法可能会丢失，并最终导致错误关联的符号导致崩溃。

旁注：为什么要包含GLFW和GLUT标题？如果您打算使用裸GLX，那么您不需要它们，也不应该包含它们。

Answer 2

发现问题，其解决方案似乎是在调用glewInit（）之前添加'glewExperimental'= GL_TRUE;

带有GLX段错误的Linux GLEW（核心转储）

2 个答案: