How to resize an openGL window created with wglCreateContext?

Question

Is it possible to resize an openGL window (or device context) created with wglCreateContext without disabling it? If so how? Right now I have a function which resizes the DC but the only way I could get it to work was to call DisableOpenGL and then re-enable. This causes any textures and other state changes to be lost. I would like to do this without the disable so that I do not have to go through the tedious task of recreating the openGL DC state.

HWND hWnd;
HDC hDC;
void View_setSizeWin32(int width, int height) {
    // resize the window
    LPRECT rec = malloc(sizeof(RECT));
    GetWindowRect(hWnd, rec);
    SetWindowPos(      
        hWnd, 
        HWND_TOP, 
        rec->left, 
        rec->top, 
        rec->left+width, 
        rec->left+height,
        SWP_NOMOVE
    );
    free(rec);

    // sad panda
     /*
    DisableOpenGL( hWnd, hDC, hRC );
    EnableOpenGL( hWnd, &hDC, &hRC );
     */

    //EDIT - instead do this....
    glViewport(0, 0, width, height); 

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity(); 
    glOrtho(-(width/2), width/2, -(height/2), height/2, -1.0, 1.0);

}

Answer 1

I'm pretty sure you don't have to delete the rendering context or the DC. However, you should deactivate it before resizing the window.

Also, you should probably only have a rendering context active while you are rendering.

Answer 2

I think you've got to call glViewport again after the client area was resized.