What are the consoles that we see in games made of? For example, Quake's console http://gregdolleysblog.files.wordpress.com/2008/01/image.png .

I've made one with AllocConsole, but that opens in a seperate window. I'm looking to make one that just takes up a portion of the screen when toggled on like we see in most games.

command parser

Well, that word helped loads. Searching "console" was not helpful at all with Google, but there are many more results for that. Thanks!

I think the way to do it would be to have 2 text boxes (CreateWindow), one read-only and one to type in. The read only would echo whatever goes into a log file and the write one would handle the commands.

You might take a look at the GLConsole project. While it is OpenGL-specific, it should still be instrumental in understanding what goes into a console system.

For the console in a couple of my games, I simply display lines of a log (rather than using std::cout) so it can display on an Android device easily.

For writing commands, I simply send the message to all of my ingame objects in the hope that one of them intercepts the message and can react / respond to it.

But depending on what API / engine you are using, it really isn't too hard to implement bespoke rather than dragging in some other project and rigging it up.

That's what I was thinking. I'd have my output go to some text file and have something constantly echo whatever is in that file onto the screen. I don't know the best way to do that though. My project is in C++ using DirectX for the graphics. I was thinking I'd just make a textbox using CreateWindowEx that displayed all the output and I'd have another textbox slightly below that to handle the input. I'd have to figure out how to do that, but it sounds reasonable.

[quote name='Kurask' timestamp='1358018205' post='5020803']
That's what I was thinking. I'd have my output go to some text file and have something constantly echo whatever is in that file onto the screen. I don't know the best way to do that though. My project is in C++ using DirectX for the graphics. I was thinking I'd just make a textbox using CreateWindowEx that displayed all the output and I'd have another textbox slightly below that to handle the input. I'd have to figure out how to do that, but it sounds reasonable.
[/quote]

Using CreateWindowEx isn't going to make a console that's really usable in-game, unless you are running windowed mode. IIRC DirectX has some font rendering classes if you are using earlier versions. Check the SDK samples.

As for logging: echoing from a file is not the greatest idea. Buffers can take time to flush. You may not want to lock a file constantly while a program is running (and conversely lock it while reading).

There are a bunch of good logging frameworks out there (check this thread on stackoverflow) that let you have multiple backend emitters. I use Boost.Log (not officially part of boost) in my projects and it works great for that sort of thing.

Most, and hereby I mean practically any game I have every played in release, use the in-game GUI to display the console, not an external window API like Windows' own.<br />Thereby they can toggle all aspects of its appearance - but there is much more to it than just pretty graphics, although ones like Source Engine's is both very pretty and functional (listing all cvars related to the chars you have typed so far and easy help/description for any cvars, for instance) IMHO, though I miss an "in-game appearance" (you cannot type while playing - console must be accessed from the menu).<br />You also need a way to bind console input (like "help", "max_fps 100", "quit", etc.) to actual source in order to command the game to do something.<br />Quake, as you mentioned, uses a system of cvars (console variables and commands) - you can read all about both online and in their released source (the newest edition of id's cvar system in actual source, that I know of, lies accessible in their Half Life 2 SDK).<br />Games like FarCry exposes this functionality via a full fledged scripting system (Lua, in this case) and binds commands/variables and the necessary callbacks this way, since they use it for all other scripting purposes anyways.<br />

Rather than outputing to an intermediate file, why not add the messages to a std::vector?
Then just display the last 10 lines or so or delete the first one until the length is less than 10 messages.

Also, rather than using Windows GUI components to display the messages, perhaps just make the messages draw to the screen as basic bitmap fonts or something. Have a basic boolean to toggle when you press the '`' key to specify if to draw the console or not every game loop.

In my engine I do something similar to this, I have a console class which stores its most recent lines internally in an std::vector and also writes that information to a file. When I use my console::outf() function the line is written to a log and added to an std::vector and the console is then drawn from the std::vector. As for drawing my console it is simply another GUI element.