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Setting up freeGLUT on g++

Last Updated 8/09/12
1)Go download the source for lesson 01. Extract the source somewhere. Now compile by entering this command:
g++ LUtil.cpp main.cpp -w -lGL -lGLU -lglut -o 01_hello_freeglut
As the programs get bigger and bigger, having to manually punch in this compilation command gets very tedious very quickly. This is why I recommend using Make.

2) GNU Make allows you to make build scripts that'll automate the compilation process.
From Basic Makefile
#OBJS specifies which files to compile as part of the project OBJS = LUtil.cpp main.cpp #OBJ_NAME specifies the name of our exectuable OBJ_NAME = 01_hello_freeglut #This is the target that compiles our executable all : $(OBJS) g++ $(OBJS) -w -lGL -lGLU -lglut -o $(OBJ_NAME)
Here we have a basic Makefile. At the top we declare and set the "OBJS" macro which specifies which files we're compiling. Then we set the "OBJ_NAME" macro that specifies the name of our executable.

After setting these two macros, we have the "all" target which compiles the program. It's followed by the dependencies which as you can see is the OBJS macro, because obviously you need the source files to compile the program.

After specifying the name of the target and its dependencies, the command to create the target is on the next line. The command to create the target must begin with a tab or Make will reject it.

As you would expect, the command to compile the program is largely the same as the command we would compile it off the command line. A key difference is that we have macros that we insert into the command which makes things like adding new files to the project must easier since you only have to change the macro as opposed to changing the whole command.

In future tutorials, we will be using more libraries and more source files. We should probably use more macros to make the process of adding them easier.
From Makefile
#OBJS specifies which files to compile as part of the project OBJS = LUtil.cpp main.cpp #CC specifies which compiler we're using CC = g++ #COMPILER_FLAGS specifies the additional compilation options we're using # -w suppresses all warnings COMPILER_FLAGS = -w #LINKER_FLAGS specifies the libraries we're linking against LINKER_FLAGS = -lGL -lGLU -lglut #OBJ_NAME specifies the name of our exectuable OBJ_NAME = 01_hello_freeglut #This is the target that compiles our executable all : $(OBJS) $(CC) $(OBJS) $(COMPILER_FLAGS) $(LINKER_FLAGS) -o $(OBJ_NAME)
Now our compilation command is much more flexible.

Near the top we have the macros that define the files we're compiling and the compiler we're using.

The "COMPILER_FLAGS" macro are the additional options we use when compiling. In this case we're disabling all warnings. The "LINKER_FLAGS" macro specifies which libraries we're linking against. Here we're compiling against OpenGL, GL Utilities, and freeGLUT. Notice how there's a -l flag before every library.

Finally at the bottom we have our target compiling using all of our macros. Thanks to macros we can very easily change the macros to add more files and libraries as we need them.

Save this Makefile code to a file named "Makefile" (case sensitive with no file extension) or you can use the one I premade here. Open a command line in the directory with the source files and run the command make all. Make will search for a file named "Makefile" in the directory Make was called in and run the Makefile that will compile your code.

Now that you have OpenGL and freeGLUT compiling, it time to go onto part 2 of the tutorial.
The documentation for OpenGL can be found here.
The documentation for GLUT (the API freeGLUT is based on) can be found here.
The documentation for freeGLUT can be found here.

Hello OpenGL Part 2: Your First Polygon