freeglut window init + glew 3.0 context creation does not work [closed]

Question

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.

Closed 9 years ago.

I am trying to create a window with freeglut and then use glew to create a 3.2 context in order to use modern OpenGL functions (using c++ and a Windows pc). My Problem is that the context creation (which i tried to do both before and after the freeglut init) does not seem to work and I get an Access Violation every time i try to use a function like glCreateShader.

The code I use Looks like this (it is located right at the start of the int main(int argc, char **argv) method):

glutInit(&argc, argv);
glutInitWindowPosition(-1, -1);
glutInitWindowSize(640, 480);
glutInitDisplayMode(GLUT_RGBA || GLUT_DOUBLE || GLUT_DEPTH);

glutCreateWindow("some title");


glewExperimental = GL_TRUE;
GLenum err = glewInit();

 if (GLEW_OK != err)
 {
   fprintf(stderr, "Error: %s\n", glewGetErrorString(err));
 }
 fprintf(stdout, "Status: Using GLEW %s\n", glewGetString(GLEW_VERSION));
 if (GLEW_VERSION_3_2)
 {
    fprintf(stdout, "OpenGL 3.2 ready", glewGetString(GLEW_VERSION));
 }
...
vertexShader;
vertexShader = glCreateShader(GL_VERTEX_SHADER); //<-- Access Violation

Also, the glew init code is copied 1:1 from their Website. I hope that my mistake is not too obvious and that someone finds the time to help me.

Answer 1

You got a problem there:

glutInitDisplayMode(GLUT_RGBA || GLUT_DOUBLE || GLUT_DEPTH);

Boolean OR || is something different than bit OR |. You want to bit OR bitmasks |, not boolean or them. Apart from that, in this way you will get a OpenGL-3 compatibility profile context, not a core context.