Question

Can someone help me ?I am trying to run the 3d point cloud viewer .However it shows me the following errors

Error   1   error C2144: syntax error : 'void' should be preceded by ';'    c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1152    Viewer
Error   2   error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1152    Viewer
Error   3   error C2146: syntax error : missing ';' before identifier 'glAccum' c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1152    Viewer
Error   4   error C2182: 'APIENTRY' : illegal use of type 'void'    c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1152    Viewer
Error   5   error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1152    Viewer
Error   6   error C2144: syntax error : 'void' should be preceded by ';'    c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1153    Viewer
Error   7   error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   c:\program files\microsoft sdks\windows\v6.0a\include\gl\gl.h   1153    Viewer

and so on …
Beginning of my code is :

    #include <cstdlib>
    #include <GL/glut.h>

    #include <cmath>
    #include "arcball.h"
    #include <vector>
    #include <iostream>
    #include <fstream>
 using namespace std;

Can someone please tell me what is going wrong?

Answer 1

Well, the first reported error is on the first line that declares a function with the WINGDIAPI modifier. Apparently, this is declared in wingdi.h. However, I’m not sure if you’re meant to #include that directly, or whether there’s a more formal recommendation for compiling opengl code in the windows environment. I’ll have a hunt around.

The page on MSDN discussing the necessary headers for OpenGL work are a bit vague, but I take:

The Windows functions that support Microsoft’s implementation of OpenGL in Windows must include the header file Windows.h.

To mean that you ought to include windows.h first.

---

Really? If I create a blank C++ project in VS2008, create an empty cpp file, copy and paste your includes in, and hit compile, I get exactly the errors you described. If I change my includes to:

#include <cstdlib>
#include <windows.h>
#include <GL/gl.h>

#include <cmath>
#include "arcball.h"
#include <vector>
#include <iostream>
#include <fstream>

Then the first reported error I get is that it can’t find “arcball.h” (hardly unexpected). Are you still getting the same errors once windows.h is included?