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Static Compile GLFW and GLEW

// August 31st, 2011 // Posted in C, OpenGL // Tagged as glew, glfw

Introduction

I need to compile GLFW and GLEW and statically link them into my OpenGL application but apparently it’s not as easy as I thought it was.

I’m using Linux Mint 9 KDE which is based on Kubuntu 10.04 and I have GCC 4.4.3 installed. GLFW and GLEW are available in Ubuntu repository as GLFW 2.6.2 and GLEW 1.5 but I want to use the latest version instead. As of this writing those are GLFW 2.7.2 and GLEW 1.7.0.

The Code

For demonstration purpose I’ve created a project directory called “test” which has a subdirectory called “external“. In “external” is where I put GLFW and GLEW sources. The code below is the main source code called “test.c“.

#include <stdio.h>
#include <stdlib.h>

#include "external/glew/include/GL/glew.h"
#include "external/glfw/include/GL/glfw.h"



int main( int argc, char const* argv[] )
{
    if( !glfwInit() ){
        fprintf( stderr, "Epic Fail!\n" );
    }

    glfwOpenWindowHint( GLFW_FSAA_SAMPLES, 4 );
    glfwOpenWindowHint( GLFW_OPENGL_VERSION_MAJOR, 3 );
    glfwOpenWindowHint( GLFW_OPENGL_VERSION_MINOR, 1 );
    glfwOpenWindowHint( GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE );

    // open a window and creates OpenGL context
    if( !glfwOpenWindow( 1024, 768, 8,8,8,0, 24,8, GLFW_WINDOW )){
        fprintf( stderr, "Failed to open GLFW window\n" );
        glfwTerminate();
        return -1;
    }

    // initialize GLEW
    if( glewInit() != GLEW_OK ){
        fprintf( stderr, "Failed to initialize GLEW\n" );
        return -1;
    }

    glfwSetWindowTitle( "Testing" );

    // dark background
    glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );

    return 0;
}

The code above will compile just fine but the executable won’t work using the latest source (it will work using GLFW & GLEW from Ubuntu repository). After banging my head against the wall and digging around the internet, I found out that the line

glfwOpenWindowHint( GLFW_OPENGL_VERSION_MINOR, 1 );

won’t work because GLFW 2.7.1 and 2.7.2 requires OpenGL 3.2. Apparently OpenGL Core Profiles only available in OpenGL 3.2. Thanks for elmindreda for pointing this out. To get around it simply change the line to

glfwOpenWindowHint( GLFW_OPENGL_VERSION_MINOR, 2 );

Compiling The Libraries

Let’s compile GLFW first. Using your favorite shell go into GLFW source directory. In my case it’s in “external/glfw“, compile and install it.

unix$ cd external/glfw
unix$ make x11

it will compile the required static lib file which is located in external/glfw/lib/x11/libglfw.a

Compiling GLEW is a bit tricky. Simply doing “make” should produce libglew.a and libglew.so for static lib and shared lib but for unknown reason it won’t work. I need to make small changes to the Makefile by adding a flag -DGLEW_STATIC to couple lines of code. Edit the file and find a line that says:

$(CC) -DGLEW_NO_GLU $(CFLAGS) $(CFLAGS.SO) -o $@ -c $<

in my case it was line 122. add the static flag into it:

$(CC) -DGLEW_STATIC -DGLEW_NO_GLU $(CFLAGS) $(CFLAGS.SO) -o $@ -c $<

few lines after that also find a line that says:

$(CC) -DGLEW_NO_GLU $(CFLAGS) $(PICFLAG) $(CFLAGS.SO) -o $@ -c $<

for me it was line 125. Change it to:

$(CC) -DGLEW_STATIC -DGLEW_NO_GLU $(CFLAGS) $(PICFLAG) $(CFLAGS.SO) -o $@ -c $<

Put Everything Together

As the final step, compile everything using GCC with these flags:

/usr/bin/gcc test.c external/glew/src/glew.o external/glfw/lib/x11/libglfw.a -lXrandr -lX11 -pthread -lm -lGLU -lGL -o test

Basically what it says is to include both glew.o (which we've just compiled using -DGLEW_STATIC directive) and static lib libglfw.a as statically linked libraries to our test.c and produce the result as a binary file called "test".

If everything went well executing the binary file should gives you a pop of OpenGL Context window.

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