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Error OpenGL GL_INVALID_ENUM (0x0500), and glewInit ()

I am new to OpenGL and trying to learn OpenGL 4 by following the http://www.openglbook.com tutorial. On the second page, we create a simple triangle using shaders. But immediately after creating the vertex shader, the program crashes. Debugging, I could find the OpenGL error GL_INVALID_ENUM(0x0500). See the code below ...

I guess I did not find any solution. Maybe you know what you are?

Edit:

So, after searching again for GL_INVALID_ENUMand glewInit(), I found that other sites already have a lot of messages, BUT: Most of them had typos in the shaders, and I definitely do not. At http://www.opengl.org/wiki/OpenGL_Loading_Library I found:

You can still get GL_INVALID_ENUM (depending on the version of GLEW you are using), but at least GLEW ignores glGetString (GL_EXTENSIONS) and gets all the function pointers.

Some recommend just ignoring the error, but I still cannot run the program ... By the way, can any of you try to run the program? If you had the same error, we would definitely know that this is the wrong IDE / Project configuration.

Specifications:

Windows 8.1 64bit
Intel Core i7-3517U with
Intel HD4000 GPU (OpenGL 4.0.0 Support)
8 GB RAM

IDE:

Eclipse IDE for C/C++ Developers
Version: Kepler Service Release 1
Build id: 20130919-0819
using MinGW Compiler

code:

#include <stdlib.h>
#include <stdio.h>
#include <string>
#define GLEW_STATIC
#include <gl/glew.h>
#include <gl/freeglut.h>


#define WINDOW_TITLE_PREFIX "Chapter 2"

// initialization
int CurrentWidth = 800,
    CurrentHeight = 600,
    WindowHandle = 0;

// timer
unsigned FrameCount = 0;

// chapter2 buffer object.........................
GLuint VertexShaderId,
       FragmentShaderId,
       ProgramId,
       VaoId,
       VboId,
       ColorBufferId;

const GLchar *VertexShader = {
        "#version 400\n"\

        "layout(location=0) in vec4 in_Position;\n"\
        "layout(location=1) in vec4 in_Color;\n"\
        "out vec4 ex_Color;\n"\

        "void main(void) {\n"\
        "    gl_Position = in_Position;\n"\
        "    ex_Color = in_Color;\n"\
        "}\n"
};
const GLchar *FragmentShader = {
        "#version 400\n"\

        "in vec4 ex_Color;\n"\
        "out vec4 out_Color;\n"\

        "void main(void) {\n"\
        "    out_Color = ex_Color;\n"\
        "}\n"
};
//................................chapter2 buffer object


// initialization
void Initialize(int,char*[]);
void InitWindow(int,char*[]);
void ResizeFunction(int,int);
void RenderFunction(void);

//timer
void TimerFunction(int);
void IdleFunction(void);

// chapter2 buffer object
void Cleanup(void);
void CreateVBO(void);
void DestroyVBO(void);
void CreateShaders(void);
void DestroyShaders(void);


int main(int argc, char *argv[]) {
    fprintf(stdout,"Starting OpenGL programm...\n");

    Initialize(argc,argv);
    glutMainLoop();

    fprintf(stdout,"Program terminated.\n");
    exit(EXIT_SUCCESS);
}


void Initialize(int argc, char *argv[]) {
    GLenum GlewInitResult; //glew

    InitWindow(argc,argv);

    //glew...........
    GlewInitResult = glewInit();

    if(GLEW_OK != GlewInitResult) {
        fprintf(stderr,
                "ERROR: %s\n",
                glewGetErrorString(GlewInitResult) );
        exit(EXIT_FAILURE);
    }
    //.................glew.

    fprintf(stdout,
            "INFO: OpenGL Version: %s\n",
            glGetString(GL_VERSION) );

    //chapter2 buffer objects
    CreateShaders();
    CreateVBO();



    glClearColor(0.0f,0.0f,0.0f,0.0f);
}

void InitWindow(int argc, char *argv[]) {
    glutInit(&argc,argv); // always the first function to call!!!

    glutInitContextVersion(4,0);
    glutInitContextFlags(GLUT_FORWARD_COMPATIBLE);
    glutInitContextProfile(GLUT_CORE_PROFILE);

    glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE,
                  GLUT_ACTION_GLUTMAINLOOP_RETURNS);

    glutInitWindowSize(CurrentWidth,CurrentHeight);
    glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);

    WindowHandle = glutCreateWindow(WINDOW_TITLE_PREFIX);

    if(WindowHandle < 1) {
        fprintf(stderr,
                "ERROR: Could not create a new rendering window.\n");
        exit(EXIT_FAILURE);
    }

    glutReshapeFunc(ResizeFunction);
    glutDisplayFunc(RenderFunction);

    //timer
    glutIdleFunc(IdleFunction);
    glutTimerFunc(0,TimerFunction,0);

    //chapter2 buffer object
    glutCloseFunc(Cleanup);
}

void ResizeFunction(int Width, int Height) {
    CurrentWidth = Width;
    CurrentHeight = Height;
    glViewport(0,0,CurrentWidth,CurrentHeight);
}

void RenderFunction() {
    //timer
    ++FrameCount;

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    //chapter2 buffer object
    glDrawArrays(GL_TRIANGLES,0,3);

    glutSwapBuffers();
    glutPostRedisplay();
}

//timer.................................
void IdleFunction() {
    glutPostRedisplay();
}

void TimerFunction(int Value) {
    if(0 != Value) {
        char *TempString = (char*) malloc(512 + strlen(WINDOW_TITLE_PREFIX));

        sprintf(TempString,
                "%s: %d Frames Per Second @ %d x %d",
                WINDOW_TITLE_PREFIX,
                FrameCount * 4,
                CurrentWidth,
                CurrentHeight );

        glutSetWindowTitle(TempString);
        free(TempString);
    }
    FrameCount = 0;
    glutTimerFunc(250,TimerFunction,1);
}
//...........................................timer

//chapter2 buffer object..................................
void Cleanup() {
    DestroyShaders();
    DestroyVBO();
}

void CreateVBO() {
    GLfloat Vertices[] = {
            -0.8f, -0.8f,  0.0f, 1.0f,
             0.0f,  0.8f,  0.0f, 1.0f,
             0.8f, -0.8f,  0.0f, 1.0f
    };

    GLfloat Colors[] = {
            1.0f, 0.0f, 0.0f, 1.0f,
            0.0f, 1.0f, 0.0f, 1.0f,
            0.0f, 0.0f, 1.0f, 1.0f
    };

    GLenum ErrorCheckValue = glGetError();

    glGenVertexArrays(1,&VaoId);
    glBindVertexArray(VaoId);

    glGenBuffers(1,&VboId);
    glBindBuffer(GL_ARRAY_BUFFER, VboId);
    glBufferData(GL_ARRAY_BUFFER, sizeof(Vertices), Vertices, GL_STATIC_DRAW);
    glVertexAttribPointer(0,4,GL_FLOAT, GL_FALSE, 0,0);
    glEnableVertexAttribArray(0);

    glGenBuffers(1,&ColorBufferId);
    glBindBuffer(GL_ARRAY_BUFFER, ColorBufferId);
    glBufferData(GL_ARRAY_BUFFER, sizeof(Colors), Colors, GL_STATIC_DRAW);
    glVertexAttribPointer(1,4,GL_FLOAT, GL_FALSE, 0,0);
    glEnableVertexAttribArray(1);

    ErrorCheckValue = glGetError();
    if(ErrorCheckValue != GL_NO_ERROR) {
        fprintf(stderr,
                "ERROR: Could not create a VBO: %s \n",
                gluErrorString(ErrorCheckValue) );
        exit(-1);
    }
}

void DestroyVBO() {
    GLenum ErrorCheckValue = glGetError();

    glDisableVertexAttribArray(1);
    glDisableVertexAttribArray(0);

    glBindBuffer(GL_ARRAY_BUFFER,0);

    glDeleteBuffers(1, &ColorBufferId);
    glDeleteBuffers(1, &VboId);

    glBindVertexArray(0);
    glDeleteVertexArrays(1,&VaoId);

    ErrorCheckValue = glGetError();
    if(ErrorCheckValue != GL_NO_ERROR) {
        fprintf(stderr,
                "ERROR: Could not destroy the VBO: %s \n",
                gluErrorString(ErrorCheckValue) );
        exit(-1);
    }
}

void CreateShaders() {
    GLenum ErrorCheckValue = glGetError();

    VertexShaderId = glCreateShader(GL_VERTEX_SHADER);
    glShaderSource(VertexShaderId,1,&VertexShader,NULL);
    glCompileShader(VertexShaderId);

    FragmentShaderId = glCreateShader(GL_FRAGMENT_SHADER);
    glShaderSource(FragmentShaderId,1,&FragmentShader,NULL);
    glCompileShader(FragmentShaderId);

    ProgramId = glCreateProgram();
        glAttachShader(ProgramId, VertexShaderId);
        glAttachShader(ProgramId, FragmentShaderId);
    glLinkProgram(ProgramId);

    if(glIsProgram(ProgramId) != GL_TRUE) {
            fprintf(stderr,
                    "ERROR: This is no GL program!\n");
            exit(-1);
        }
    glUseProgram(ProgramId);

    ErrorCheckValue = glGetError();
    if(ErrorCheckValue != GL_NO_ERROR) {
        fprintf(stderr,
                "ERROR: Could not create the shaders: %s \n",
                gluErrorString(ErrorCheckValue) );
        exit(-1);
    }
}

void DestroyShaders() {
    GLenum ErrorCheckValue = glGetError();

    glUseProgram(0);

    glDetachShader(ProgramId, VertexShaderId);
    glDetachShader(ProgramId, FragmentShaderId);

    glDeleteShader(FragmentShaderId);
    glDeleteShader(VertexShaderId);

    glDeleteProgram(ProgramId);

    ErrorCheckValue = glGetError();
    if(ErrorCheckValue != GL_NO_ERROR) {
        fprintf(stderr,
                "ERROR: Could not destroy the VBO: %s \n",
                gluErrorString(ErrorCheckValue) );
        exit(-1);
    }
}
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1 answer

, , : , , , , .

  • glu. gluErrorString(...). glewGetErrorString(...). glu.
  • , : glutInitContextVersion(4,0);. , , , glew OpenGL 4.

. , ( )! :)

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