Superbible 6th edition undefined platform error - opengl

Question

I just started off with learning openGL from the superbible(6th edition) with code::blocks.
But when i try to run the first sample code i get an undefined platform error from the sb6.h file.
sample code:
#include "sb6.h"
// Derive my_application from sb6::application
class my_application : public sb6::application
{
public:
// Our rendering function
void render(double currentTime)
{
// Simply clear the window with red
static const GLfloat red[] = { 1.0f, 0.0f, 0.0f, 1.0f };
glClearBufferfv(GL_COLOR, 0, red);
}
};
// Our one and only instance of DECLARE_MAIN
DECLARE_MAIN(my_application);
Does anyone know how to fix this?

Answer 1

This is because that header file expects one of _WIN32, _LINUX or __APPLE__ to be defined. Usually these are defined by the compiler or one of the platform's headers. You could also pass them to your compiler, e.g. -D_LINUX or define it in your source file before you include their header, e.g.:
#ifndef _LINUX
#define _LINUX
#endif
gcc actually defines __linux, but this is not what the header file is checking for.

Answer 2

It appears you are not using the CMake provided along with the projects. The CMake build process automatically adds -D_LINUX, on Linux systems when detected. Refer to the file CMakeLists.txt (https://github.com/prabindh/sb6code/blob/master/CMakeLists.txt) around line 135. If you are not using CMake, you will need to do a similar addition to the build flags.

Answer 3

The end of sb6.h has a set of preprocessor defines for various operating systems, and the '#elif defined _LINUX || defined APPLE' is not reached for some reason. I commented out from '#if defined _WIN32' to 'APPLE' and from '#else' to second last '#endif'. Between those commented out sections is the #define DECLARE_MAIN(a)' that is needed.
Good luck getting the rest of the programs to compile.