Thread: Tell me about C/C++

Originally Posted by ninja9578

Good start, maybe the next thing you can learn is how to save your screenshots in pngs instead of jpgs

A haw haw

Looks like you've got quite a bit of work to do there...

How do I get away from the command prompt though? Like I want my own window made.

Edit: Also, do I use C++ in other things like Aleggro or SDL?

Thanks guys.
I'm going to learn C++ first, then maybe C. Oh, Ninja, what compiler/text editor do you use? I'm using code::blocks, but I also have xcode though it's more confusing. Which do you suggest?(I'm asking you because I now you're an apple guy )

Originally Posted by slayer

A haw haw

Looks like you've got quite a bit of work to do there...

How do I get away from the command prompt though? Like I want my own window made.

Edit: Also, do I use C++ in other things like Aleggro or SDL?

Not really, because I've mapped it all out, I think it will be fairly easy, each of those components shouldn't take more than 50 lines of code.

C / C++ is platform independent, so it has no support for windows natively. You have to use an external library. This could be X11, GTK, Windows API, wxWidgets, Qt, or GLUT. For games, GLUT is the easiest choice because it's an extension on OpenGL. GLUT is also the easiest for a beginner because it's C based, therefore there is no complex C++ functionality like Templates and inheritance and stuff.

Allegro and SDL can both be used in C++, however, OpenGL has been the graphics standard for 15 years.

Originally Posted by guitarboy

Thanks guys.
I'm going to learn C++ first, then maybe C. Oh, Ninja, what compiler/text editor do you use? I'm using code::blocks, but I also have xcode though it's more confusing. Which do you suggest?(I'm asking you because I now you're an apple guy )

I use Code::Blocks when I'm writing code on Windows or Linux, and XCode and Code::Blocks when writing code on OSX. Code::Blocks is far simpler, however XCode is the most powerful IDE out there. So what I do for big projects is I write small components in XCode and use all of XCode's debugging tools and such to make sure it's right, then put them together in Code::Blocks.

How exactly do I draw an image onto the screen?

And I found a tutorial for making a window. I'm not sure if it was just the tutorial, but there is a butt load of code involved for making something as simple as that. You'd think it'd be easier right?

Originally Posted by slayer

How exactly do I draw an image onto the screen?

I'm not a graphics guy (I hardly ever program GUI apps)

but using ninja's sugesstion of GLUT
here's sample code from a Glut tutorial

Code:

#include <GL/glut.h>

void renderScene(void) {
    glClear(GL_COLOR_BUFFER_BIT);
    glBegin(GL_TRIANGLES);
        glVertex3f(-0.5,-0.5,0.0);
        glVertex3f(0.5,0.0,0.0);
        glVertex3f(0.0,0.5,0.0);
    glEnd();
    glFlush();
}

void main(int argc, char **argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DEPTH | GLUT_SINGLE | GLUT_RGBA);
    glutInitWindowPosition(100,100);
    glutInitWindowSize(320,320);
    glutCreateWindow("3D Tech- GLUT Tutorial");
    glutDisplayFunc(renderScene);
    glutMainLoop();
}

This will open up a window, 320x320, with a triangle in it

*sigh*

I think I'll just go back to learning lines of text and numbers...

Don't be intimidated, it's really quite simple if you know what each command does. Follow the path of the code, it always starts at main, and I've put comments around the OpenGL and GLUT stuff explaining what each function does.

Code:

#include <GLUT/glut.h>

void renderScene(void) {
    /*
	   glClear erases what's already stored in the drawing area,
	   GL_COLOR_BUFFER_BIT is the colour to restore it too, by default, it's black
    */
    glClear(GL_COLOR_BUFFER_BIT);
    
    /*
	   We want to draw a triangle, so tell OpenGL that the next drawing functions that we are doing
	   should be done in triangle mode
    */
    glBegin(GL_TRIANGLES);
	   /*
		  These are the verticies of the triangles, now with the default setup on the window, the window is 1x1, so
		  the coordinates are in relation to that.
	   */
	   glVertex2f(-0.5,-0.5);
	   glVertex2f(0.5,0.0);
	   glVertex2f(0.0,0.5);
    //This tells OpenGL that I'm done placing my coordinates and that it can draw it
    glEnd();
    /*
	   This one is also pretty complicated, OpenGL buffers it's drawing commands for optimization purposes
	   this glFlush command tells OpenGL that there are no more commands to come, and that it can go ahead and
	   finish drawing whatever's still in the buffer
    */
    glFlush();
}

int main (int argc, char ** argv){
    /*
	   This line initialized GLUT, which is the window engine and the interface to OpenGL
	   Internally, it loads the libraries and sets everything up
    */
    glutInit(&argc, argv);
    
    /*
	   This sets the initial display mode for OpenGL
	   GLUT_SINGLE means that it's using a single drawing page, so everything that gets drawn goes directly onto the screen
		  games should be double buffered to elimiate flickering
	   GLUT_RGBA tells glut that the pixels will be rendered in Red, Green, Blue, Alpha order
    */
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
    
    //These should be obvious, they're setting the window's position
    glutInitWindowPosition(100,100);
    glutInitWindowSize(320,320);
    //Creates the actual window
    glutCreateWindow("3D Tech- GLUT Tutorial");
    
    /*
	   This is a little advanceds, this is registering what's known as a callback function.  GLUT basically needs to know what do it
	   if it's in a situation where it needs to draw.  This could be the intial render, or of another window is moved over it, or if
	   it's resized.  glutDisplayFunc is given the name of the method that glut should call when it needs to redraw
    */
    glutDisplayFunc(renderScene);
    /*
	   Start the main loop :)
    */
    glutMainLoop();
    return 0;
}

Originally Posted by slayer

I'm learning C++ to learn how to make my own game engine. I don't really know anything about C.

If you're just getting started with C++, I recommend a few smaller (like, MUCH smaller) projects first.

Originally Posted by Replicon

If you're just getting started with C++, I recommend a few smaller (like, MUCH smaller) projects first.

Indeed,
first learn the language, then do something small and easy to get the hang of things

Originally Posted by Ynot

hangman is always a good first game

pick a random word from file of possible words
let the user guess letters
print letters found, and underscores for not found
keep a count of num guesses

You've just started on your journey as a bridge-builder
Your ultimate aim is this
http://secretperson.files.wordpress....n-bridge-l.jpg
but you've got to start off building a few of these first
http://www.freeimageslive.co.uk/file...46.preview.jpg

I agree, you saw my design right? Mario is a fairly simple game, yet it's quite a lot of classes and functionality. I could probably knock it out in a day, but I'm very experienced.

I guess I made my first game!

Simple if/else statement set up.

Code:

#include <iostream>
using namespace std;

int main()
{
    int a;

    cout << "Please enter the number 3: ";
    cin >> a;
    if ( a == 3)
    {
        cout << "You have entered the right number!";
    }
    else
    {
        cout << "You lost the game.";
    }
    return 0;
}

If you enter the number 3, you win! But if you don't, then you lose!

How would I set it up so it repeats the first line of code?

I want to set it up so that if the player enters the wrong number, then it goes to repeat the "Please enter the number 3" part. Or, if they get it wrong, then it asks for the player "Do you want to play again? Y/N" and if they enter Y then the whole thing repeats itself, or if they enter N, then the game exits.

You need a loop. C++ has a number of loops, but the one that you want is the do/while loop Basically it's saying do {this code} while (this is true)

Code:

#include <iostream>
using namespace std;

int main()
{
    int a;
    char cc;
    
    do {
	   cout << "Please enter the number 3: ";
	   cin >> a;
	   if ( a == 3)
	   {
		  cout << "You have entered the right number!";
		  return;
	   }
	   else
	   {
		  cout << "You lost the game." << endl << "Would you like to play again? Y/N";
		  cin >> cc;
	   }
    } while (cc != 'Y');
    return 0;
}

Code:

#include <iostream>
using namespace std;

int main()
{
    int a;
    bool correct = false;
    char play_again;

    while ( ! correct )
    {
        cout << "Please enter the number 3: ";
        cin >> a;

        if ( a == 3)
        {
            correct = true;
            cout << "You have entered the right number!" << endl;
        }
        else
        {
            cout << "You lost the game." << endl;

            cout << "Play again? (y/n): ";
            cin >> play_again;

            if ( play_again != 'y' )
            {
                correct = true;
                cout << "Thanks for playing." << endl << "Goodbye!" << endl;
            }
        }
    }
    return 0;
}

although I'll leave you with this
The above is not very clear to read (it's all in one function)
your job (when you get far enough along with the language) is to clean this up with a much simpler program flow


*edit*
beaten to it

What does the "char" do?

it's the character datatype
meaning it stores a single character

a sequence of character datatypes "strung" together is where the word "string" comes from

Edit: Never mind. Note to self: Learn to see if there are more pages.

But yeah, I also support you doing some smaller projects first.

Have you given any thought yet to C#?

C is pretty much dead except for embedded solutions, C++ is still a great language and supports object oriented design, but with modern hardware, all but the most time critical tasks can be handled with C#. You also have the ability to call C++ unmanaged code from within wrappers if you have a section that needs to execute at it's fastest.

My suggestion for a compiler is Visual Studio 2005 or 2008 (2003 is OK, but doesn't support the .NET 2.0 framework well). I've been using the Microsoft Cxx compilers since they were introduced and really like it. In fact I'm using VS2005 as we speak.

Originally Posted by Seeker

Have you given any thought yet to C#?

C# is generally just used for Windows exclusive applications, though, and they require the .NET network to run. It's harder to write cross-platform applications. It's not as elegant at making native applications, though you're saved from hunting for external libraries or writing system-call wrappers yourself.

Originally Posted by Seeker

C is pretty much dead except for embedded solutions, C++ is still a great language and supports object oriented design, but with modern hardware, all but the most time critical tasks can be handled with C#. You also have the ability to call C++ unmanaged code from within wrappers if you have a section that needs to execute at it's fastest.

I thought C was commonly used for time-critical operations still, such as graphics modules.

Originally Posted by Seeker

My suggestion for a compiler is Visual Studio 2005 or 2008 (2003 is OK, but doesn't support the .NET 2.0 framework well). I've been using the Microsoft Cxx compilers since they were introduced and really like it. In fact I'm using VS2005 as we speak.

I do however agree that Visual Studio is an excellent set of coding tools. I use VS2008 professional myself (no, it's not pirated... but neither is it bought).

Even unsafe C# code doesn't run as quickly as C++.

It's also very heavily dependent on the Windows runtime libraries. I think C# is an atrocious attempt at making C++ more like Java. C and it's derivatives are not meant to be safe, they're meant to do exactly what you tell them to do.

Wow...
I think I'm going to attempt to start learning C++ again...

I gave up pretty darn quick last time. Mostly because I was trying to get code::blocks or something and it wasn't working... is code::blocks like a plugin to microsoft visual C++ or something?
In fact, talking of which, is microsoft visual C++ the right thing to use?

EDIT: Hold on... is code::blocks entirely seperate from windows visual?

code::blocks has nothing to do with MS
It's a cross-platform IDE for C & C++

I wouldn't get too hung up on IDE's to start with
Just code in a decent text editor (eg. Vim) and compile on the CLI

Ah yea, I had a look around google just there.

And... hrm... by the way I see it, I would rather use code::blocks.

I don't want to have to end up changing what I use once/if I get better at it. Besides... code::blocks looks more appealing than vim, and less complicated looking.

Code::Blocks is great, it's what I use professionally on Windows and Linux. And it does all the complicated linking crap for you.

Cool, I have downloaded and installed code::blocks. Then it asked me what compiler to use, so I used windows visual C++ since it was already on my computer from last time I tried all this stuff.

My problem now is that it won't build or something, I click build, then I click run, and it says I need to build it. I then tried "build and run" and it just kinda does nothing. Don't know what the fuck is wrong here.