Failed to Initialize GLEW. Missing GL version

问题:

I've tried to set up SFML 2.0 with the latest version of the qt creator, I've set up SFML right and I imported a small game I wrote in visual studio. Upon compilation, I get this:

What I tried

• Reinstalling the entire qt SDK and qt creator IDE from scratch
• Reinstalling SFML
• reinstalling mingw
• I tried to write a simple program to make sure it's not my code, the program compiles correctly but when I close the application, I get OpenGL errors which is not normal
• I tried posting a thread on the SFML forums but to no avail.
• Googling the errors shows a few results, which are specific to OpenGL, and which are too localized, they don't apply to me, no answer for this happening in SFML 2.0

Additional details

• I'm running windows XP SP3, latest version of mingw and qt SDK and SFML

• The code I'm trying to work with works without any errors or even warnings on Visual Studio 2010 and Code::Blocks

• Yes, I am sure that SFML is set up on my IDE, basic code works but shows those errors and more advanced code shows all sprites and text as boxes.

• I did not compile SFML myself

• My gcc version is 4.6.2

• My gcc is a DW2 one

I'm getting no results, I don't even know how to remotely get close to fixing this, not even where to start.

EDIT I can't show you all of my code, it's over 20 files and I'm almost 90% sure it's not my code, I've said it above: I can run this code without any warnings or even errors on any IDE except qt creator.

回答1:

It's because you are not initializing OpenGL. Example with the lib glut.

Wrong:

 glewInit();  // ERROR MISSING GL VERSION
 glutInitDisplayMode(GLUT_RGB); 

Good:

 glutInitDisplayMode(GLUT_RGB);
 glewInit();

EDIT I think for SFML:

 sf::Window   App(sf::VideoMode(400, 400, 32), "Window");
 glewInit();

EDIT 2 Test this code.

#include <SFML/Window.hpp>
#include <iostream>
#include <GL/glew.h>

int
main(int, const char**)
{
    GLenum      err;

    std::cout << "Start" << std::endl;
    std::cout << "Test 1" << std::endl;
    if ((err = glewInit()) != GLEW_OK)
        std::cout << glewGetErrorString(err) << std::endl;

    std::cout << "Init window" << std::endl;
    sf::Window  app(sf::VideoMode(400, 400, 32), "Windows");

    std::cout << "Test 2" << std::endl;
    if ((err = glewInit()) != GLEW_OK)
        std::cout << glewGetErrorString(err) << std::endl;
    std::cout << "End" << std::endl;
    return 0;
}

My output:

Start
Test 1
Missing GL version
Init window
Test 2
End

Compile with: g++ -W -Wall -Werror main.cpp -lsfml-window -lGLEW

Good Luck ;)

回答2:

At the request of user3648895, I am posting my answer outside of the comments separately.

For those using GLFW instead of SFML, you need to call glewInit() after glfwMakeContextCurrent

回答3:

If you're using glew with glfw, use glfwMakeContextCurrent (https://github.com/Cloudef/glhck/issues/15)

回答4:

For those using SDL2's Renderer functions, it needs to be right after SDL_CreateRenderer.