Game Development

Like... I get excited (can you tell?) when this comes up. In UT2k3 for example, when a player is killed, only the pawn is killed, the actor continues on and is given a camera to control. When it's time for the player to respawn, a new pawn is created for him, and the actor is pointed to the pawn and away he goes.

Pablo Ariel

yes it is

John McD.

Also... When a pawn walks up to a vehicle and presses the "enter vehicle" key, the "pawn" is placed into the vehicle, and at the same time, the actor is re-routed to control the "vehicle" pawn, and now the actor is controlling the vehicle!

Cool eh?

Pablo Ariel

2:21 AM

ah so the actor would be like a viewer?

which then binds to something?

John McD.

It's all based around this "link" between the actor and pawn

Yeah, it's like a viewer, BUT, it also handles all input

Orr... Output

So.. and Actor translates the player's key presses into commands

Pablo Ariel

interesting, like a "gamer interface"

John McD.

That way, an AI "Actor" can be created, and command the pawn in the same way

Yeah, it's really cool

And at the same time, a Network "Actor" can also be created, and again, the commands to to the pawn

Yeah, real fun

I made an Actor and a Pawn (I called it Force) class in my game, and each are just under 120 lines. Really small classes, and very little refactoring when you get to a point where you think it might be useful

Pablo Ariel

I was thinking

I remember some isometric games and they deal with the y axis

ie moving a sprite up and down in an isometric way

""

Raven Dreamer

Back.

John McD.

2:30 AM

@PabloAriel What about the y axis?

Pablo Ariel

do you do it in your game? those algos in your question you posted work for that don't they?

there is a game I like a lot (I don't play it often because it's too old) which I would like to do rev eng

John McD.

Well... I don't actually know. I am using a strictly (well..) 2D world where Z is unused (toward and away from the screen)

Pablo Ariel

no no not z but the Y from the isometric world

John McD.

Well... all of my objects have and x,y coordinate in my game...?

Pablo Ariel

I mean you have the height in the isometric coord system then you have to translate to screen

for rendering

ah yes well idk actually!

now I know

John McD.

2:32 AM

Yeah, I'm not using depth

Pablo Ariel

but you use those functions don't you?

John McD.

So it's really only 2D, nothing is 3D about it

Pablo Ariel

not depth but

you use x and y for the ground plane (in the isometric world) don't you?

John McD.

I use Y, but I suppose... I'm using it in-place of Z? I don't know. I only use X and Y

Pablo Ariel

then if the ground is x, and y ( a 2 dimensional ground), do you use an Z axis on it? I mean things can go up and down?

sorry

I edited it

John McD.

2:35 AM

No, things don't go towards or away from the screen

eg: cell.stat-life.com/images/stories/AsteroidOutpost/…

(I should really update that image)

By the end of the weekend, I should have a bunch of new and cool images to replace that one

Raven Dreamer

Oooh

Is that radar all asteroids?

John McD.

Heh, lol

yes

Those dots are all asteroids

Pablo Ariel

nooo not from the screen! but on the isometric world, can there be ie. ufos or harriers that do vertical takeoff?

John McD.

and I changed the algorithm for asteroid generation a long time ago

@PabloAriel Well... not yet

Not sure if I plan to take advantage of the 3rd dimension

I mean.. I plan to abuse the 3rd dimension (It is a space game), but.. actually use it in a 2D game? I donno

Like: "No no no, He was just flying under the asteroid"

heh

Pablo Ariel

the games I remember they did were UFO/X-COM and Transport Tycoon (there are more games that apply the 3 axis in the same way) and even if they had 1 or 2 values in the world Y axis (x-com had 4 Y levels of tiled maps) they made it look very nice

John McD.

2:43 AM

Interesting

Raven Dreamer

Xcom is an interesting case

Pablo Ariel

ie I believe the TT worked with 2 planes, one for "sky" and one for "ground" but the transition was a landing/takeoff

Raven Dreamer

(for graphics)

John McD.

I admitted it earlier today (for the first time), so I may as well admit it again with a link. I am essentially cloning "The Space Game": kongregate.com/games/CasualCollective/the-space-game

Pablo Ariel

I ripped the world coords from the x-com world (the earth-geoscape one)

picasaweb.google.com/101852552240853074237/…

John McD.

2:45 AM

Except bigger and better, and more AI, and more structures, and more upgrades, and more More MORE

Raven Dreamer

Yeah, I remember playing that game.

(Also, I keep misreading your name as John MD)

John McD.

@PabloAriel Heh, Interesting. Have you heard of the open-source game: AI:UFO Alien Invasion: ufoai.ninex.info/wiki/index.php/News

@RavenDreamer LOL

I bet you see me with my arms crossed in scrubs

Raven Dreamer

Nah, it's because there's a stackexchange member called "Javadoc, MD"

and you both have J names.

John McD.

ic

I should probably edit my name to be "McDonald"

heh, it's obvious

How long does that take to propagate I wonder

Pablo Ariel

yes I've even downloaded the sources but it's still... ahh no no, it's updated!! I should read more about it

John McD.

2:51 AM

I haven't played the original X-Com series (I know), but I do enjoy this open-source version

Raven Dreamer

@JohnMcD If you just changed your name? Refreshing the chat should do it.

Oh, John.

John McD.

I pressed F5

Raven Dreamer

Steam. 5$. Every official xcom game ever.

one bundle

John McD.

Hah

Orly?

Raven Dreamer

Even Interceptor, which is impossible to try and play because there's no manual, no in-game help, and the game is so poor that there's no guides in the internet.

John McD.

2:52 AM

Complete pack is $15!!

Liar

:p

Raven Dreamer

Sales, John.

Sales!

Hm. How to implement movement.

John McD.

@RavenDreamer heh, so why would I pay $5 for that when I can get... some percent of the enjoyment by downloading and playing the open-source clone?

Raven Dreamer

Should a keypress call the "move" method of the player object? Or should I base it on if the key is depressed...

Pablo Ariel

actually I'ev tried to play patched versions of the older x-coms and it's not the same... many people liked that game because you could easily "hack" it, I've even modified all texts of the intro when I was 14, and there are many times when even without changing anything the game crashes

Raven Dreamer

@JohnMcD - why buy anything when you can pirate it?

John McD.

2:54 AM

@RavenDreamer Umm... It should move as long as the key is held down

Raven Dreamer

Simply put: useability

John McD.

@RavenDreamer lol

Raven Dreamer

Having steam run xcom for you is a lot simpler than trying to finagle dosBox into running the game for you.

John McD.

I didn't say "pirate", I said "open source"

Pablo Ariel

no no actually the steam version crashes

Raven Dreamer

2:55 AM

I know.

Not for me. Not anything memorable, anyway.

John McD.

heh, I know you heard me... evil eye

:p

Raven Dreamer

So you're saying I should repeatedly call the "update" command on the player object while the key is depressed?

Or move command, I suppose.

John McD.

@RavenDreamer Well... In a typical game, there is a "Game Loop", and each iteration of the game loop will execute the "Update" method for each and every object in the world

Pablo Ariel

well it will eventually, the thing is with the DOS version you can see a lot of things of the program working, ie you can make the game read invalid memory, there are limits overflows, etc, and it's really interesting, and sometimes it's even fun, the DOS version never crashes

John McD.

@PabloAriel heheh

Raven Dreamer

2:58 AM

@JohnMcDonald Right. So put the commands in the "Update" method.

John McD.

I'm starting to get your sense of humour

@RavenDreamer Well... the simplest way (not good for large games) is to handle the input straight inside the update method of the object that will be responding to the input

Raven Dreamer

Yea, that's what I'm doing.

John McDonald

Please keep in mind that this is not an expandable model, and if the game goes much beyond the current confines, it will become overly complex

Raven Dreamer

Yeah, the focus of the assignment is the GameObject

Pablo Ariel

and if the game is very simple the controller system would become overly complex XD

Raven Dreamer

3:01 AM

More re-useable scripting comes later, presumably.

John McDonald

yup, I figured as much, that's good

You don't need to complicate things with an Actor and Pawn until the time comes

And you won't have an AI actor control the same pawn that the current user is controlling, so it's all good, :)

Raven Dreamer

So for my entity's collision code, I guess I need to go through every object and check for a collision?

John McDonald

and :D, 11 ups

@RavenDreamer Yes, It sounds slow, but it's really not

Computers are really, really, really... really fast

Raven Dreamer

I should probably go ahead an implement something to keep track of every object now, then.

I think I'm not supposed to use an array, though?

John McDonald

Like a Vector? (that's Java right?)

Meh,

I would

Raven Dreamer

3:06 AM

I don't know how to use a vector.

John McDonald

A Vector is essentially an Array, but... More awesome

It maintains an order, you can access it by index, and you can add and remove elements from it without any limitations

Use it whenever possible

Raven Dreamer

I wish the name of this language wasn't also a common english word.

Makes searching for relevant tutorials irksome.

John McDonald

the Java Doc is amazing: download.oracle.com/javase/1.4.2/docs/api/java/util/Vector.html

imo

(not sure if that's the right version, but)

:D Hah, that is cool "The Iterators returned by Vector's iterator and listIterator methods are fail-fast"

That's great. I am an advocate of Fail-Fast

:D The name change propagated

Raven Dreamer

I don't know that term?

objectsVector.add( platformOne = new MovingPlatform(width/2, height/2, 80, 20, 45, 0));

John McDonald

Fail-Fast is a term that is used for: "Failing as soon as there's a problem". Make the problem evident, make the problem show up in the stack trace. Never make code "roll over" a potential problem, just to have it crop up later on.

Raven Dreamer

3:14 AM

Is there any reason I should do that command as two lines instead of one?

Ah, yes. Fail-fast is useful.

I had the 'pleasure' of working on a project that made no indication there was an error except in the external error log. I was wondering what was going on for hours, until I realized the errorlog kept getting updated with the answer I was looking for.

John McDonald

@RavenDreamer It's personal preference really. I would have it as 2 lines for clarity, and clarity is what you should strive for.

@RavenDreamer :/ yeah, great eh? And that's all probably because the developer didn't want to disturb the user with irrelevant errors

makes me sick, :(

Pablo Ariel

well there are some errors that make an app crash when they shouldn't, and it happens a lot with apps that access varied hardware such as games

Raven Dreamer

I think I should write a class that extends vector...

So it can fit into my gameobject hierarchy.

Pablo Ariel

I like apps crashing when things go wrong but when the game is shipped I would like to play the game even if a texture is missing

or ie I would like to change my video config with the game running

of course it should crash on fatal errors but why every error is a fatal error in some apps? even if from the user's point of view they are not relevant at all

John McDonald

@PabloAriel Here's the paper I read a while back on Fail Fast, and yes, there are situations where you should not fail: google.ca/…

Pablo Ariel

3:22 AM

thanks!

John McDonald

@RavenDreamer Do you really need to extend the Vector class? (java's mutable list class)

@PabloAriel Yeah, it's a good read

Raven Dreamer

@JohnMcDonald I don't need to extend it. I need to extend my GameObject class with a new class that is mostly a vector. That way I can parent all my other GameObjects to it, and still get vector functionality.

John McDonald

@RavenDreamer What?

Umm

Wait wat

Raven Dreamer

Currently, I have a vector containing every one of my gameObjects.

However, there is no way for the member objects to interface with the vector holding them.

My GameObject class has a "parent" field, which is another game object.

John McDonald

Ok...

So what's the issue?

One game object can't see an other one?

Raven Dreamer

3:26 AM

One game object can't see something that isn't itself a game object.

John McDonald

Yeah... there are ways to handle that, in my game, I give the objects access to the "game". The objects can then ask the "game" for other objects

(as simple as an accessor)

Raven Dreamer

that's a good point

Easier to implement too!

John McDonald

I've been making games for long enough, and I'm anal enough to ask: "Why does X need to access Y?, and if so, how should X access Y"

The answer is usually a really clean and maintainable architecture

hmm, so.. I have .. 3 relates projects. One is my sprite maker, then there's the sprite library (that uses the output from the sprite maker), then there the sprite library tester that I simply use for testing. I already have my sprite library as an open source project, but do I make a new one for the sprite library+tester, or do I simply make a subdirectory for the pair?

So: Sprite Maker -> Sprite Library for C# -> Sprite Library Tester for C#

Raven Dreamer

I am the wrong shark to ask.

John McDonald

:p

user4704

3:41 AM

I would make a directory for the "tester"

John McDonald

@RavenDreamer So what's your 42k rep worth?

user4704

As a subdirectory, make an "Externals" or "Dependencies" directory.

Raven Dreamer

All on Gaming.

user4704

Put the built binaries or an externals or vendor branch for the sprite library itself in there.

Raven Dreamer

@JohnMcDonald I can tell you how to win at Minecraft, Civilization V, or League of Legends, if you'd like, but I don't see how that will help you.

John McDonald

3:42 AM

@JoshPetrie All in the same repo?

user4704

Probably not.

user4704

In general, no.

user4704

In this case there's also an argument to be made that your "tester" is basically a test framework for the library itself and would instead belong in a "Tests" directory of the library itself.

Raven Dreamer

Yay for absolute values!

John McDonald

@RavenDreamer Lol, Win @ Minecraft: chzragecomics.files.wordpress.com/2011/07/…

Raven Dreamer

3:44 AM

Dwarf Fortress also.

Shocking, I know, but you can win that game.

John McDonald

@RavenDreamer :O

user4704

Dwarf Fortress is the best.

Raven Dreamer

Of course, you need to make your own rules, so if you're not winning, you're either doing very badly, or indulging in some good ol' fashioned masochism.

John McDonald

@JoshPetrie Hmm, you're making me wonder

user4704

About?

John McDonald

3:48 AM

Well... I have my sprite maker, that makes sprite XML and PNG files, and those are designed to be loaded by anyone willing to write an XML loader OR use my existing Sprite Library (SpriteLib [creative name eh?]) that will do this for a C#/XNA application.

Now... On top of that... I have a very simple application that tests some of the basic functionality of the SpriteLib (for C#)

(Visual test, not that it really matters what kind of test)

So... there is a direct dependence

user4704

I way I'd consider ordering that in one repo would be to have the library be the principle product, so you'd have /SpriteLib. And then in /SpriteLib you'd have Source/Products/SpriteLib (the lib itself) and Source/Tools/SpriteMaker, and Source/Samples/*

John McDonald

A -> B -> C, where B->C could be replaced

user4704

Where Samples contained a bunch of projects showing off features of the library, which also act as a higher-level tests.

user4704

This is basically what we do in SlimDX: github.com/SlimDX/SlimDX

John McDonald

Interesting...

user4704

3:54 AM

You can also see some examples of how we handle dependencies in there too.

John McDonald

Yeah... that sounds a bit like the Library I made, and the samples/tester of the library

user4704

SlimBuffer and SlimMath are both libraries we publish that SlimDX depends on, but we only keep the binaries of specific versions in SlimDX's repo and not the full code tree.

John McDonald

But mine feels like it's one level before that. So: Editor -> (output files) -> (input files) -> Sprite Library in C# -> Sprite Library Tester for C#

hmm..

Pablo Ariel

I started playing the space game :$

John McDonald

@PabloAriel :D

Once you get closer to end, tell me what you thought

Raven Dreamer

3:58 AM

Any way to specify the type of object stored in a vector?

user4704

std::vector?

Raven Dreamer

As in, a vector of, say, Strings, instead of a vector of generic objects?

user4704

Or...?

Raven Dreamer

Java

John McDonald

@PabloAriel (btw, even though I'm cloning it, I haven't even completed the last level)

In Java, I... don't think so..

Unless things have changed in the past 10 years (lol)

user4704

4:00 AM

If you are doing import java.util.Vector, can't you just to Vector<String>?

Raven Dreamer

You know... I probably can.

user4704

I could have sworn I've seen such code before.

user4704

But I don't really know Java so there's that.

John McDonald

In C#, people used to use a ArrayList that is very very similar to a Vector in Java. Thankfully they replaced it with List<T>

Raven Dreamer

Yup. One line fix. Thanks, Josh.

Pablo Ariel

4:01 AM

@JohnMcDonald I will, thanks for the links! and don't worry about finishing the game for cloning it, is the gameplay what counts

user4704

Should have deprecated that CLR 1.0 crud :\

John McDonald

@RavenDreamer Awesome

@PabloAriel Yeah, I am working toward a multiplayer clone of that game to this day. Does it count as a clone if I'm adding to it already?

Raven Dreamer

it bothers me that coordinates are inverted. A positive y velocity means you're falling down!

Pablo Ariel

no no it's not a clone is your game

John McDonald

@RavenDreamer heh, that sucks

Raven Dreamer

4:04 AM

@JohnMcDonald Just the way graphics are handled.

Not any different than getting used to quirks of any language, I suppose.

John McDonald

@PabloAriel Well... have you downloaded the down of them? I really am cloning the game

@RavenDreamer yeah maybe eh? It's easy enough to convert to your own coordinate system. I use "up" as +y as "North", and "right" as +x as "East" and 0 degrees = North, and 90 degrees = East

user4704

@RavenDreamer Our coordinate system at work uses -Z as "up."

Raven Dreamer

Minecraft has height on the Y axis.

Dwarf Fortress it's Z levels.

How can I reconcile my two loves?

John McDonald

yeah... Y and Z tend to differ between 2D and 3D apps

Raven Dreamer

Dwarf Fortress is 3D

It's just not 3D graphics

user4704

4:07 AM

Use -X. Be different.

Pablo Ariel

@JohnMcDonald I will play both before answering that, but I believe even if it's very similar it may be a different game

Raven Dreamer

Also, I hope to some day be able to write something vaguely Minecraft / Dwarf Fortressy.

So maybe I will use -x

John McDonald

2D is usually X & Y (Z is completely ignored or whatever needs to be done). 3D is usually X = horizontal, Y = either up and down OR towaed and away from the screen, Z is the opposite of Y. No?

Raven Dreamer

Sounds about right.

John McDonald

Y and Z are often interchanged, from my limited experience

X is always the same though

user4704

4:10 AM

Something like that is the most natural for most humans to think about.

user4704

It's all trivial to switch between though.

John McDonald

It is

So... how do you find Git Hub?

user4704

It's good.

John McDonald

I've only really used Source forge (fuuuull of ads), and Google Code

I have been tempted with distributed version control systems, and I tried merc out for a while, but I remember having some UI complaints, :/. At least for a single developer (as I always am)

user4704

Sourceforge was tolerable about fifteen years ago. Now it's crud.

user4704

4:20 AM

Most DVCS systems have crap UI and can be a pain to use on Windows.

John McDonald

@JoshPetrie heheh, Very true. And that's why I've been looking for a new home

user4704

git is a bit of a chore but I think it's better than the other options.

user4704

Google Code is nice.

John McDonald

Yeah, google code is quite nice so far. The only complaint is that nobody looks there for useful software, :(

user4704

I dunno, I don't think its worth using that as a basis for judging -- the project will still be searchable via Google, which everybody uses to find things.

John McDonald

4:23 AM

:/ Maybe I should care as much because the quality of the user that downloads my stuff from google code will be X times better than those looking on sourceforge

user4704

I never go to any hosting sites like that to search them for software; I just end up there for specific projects.

John McDonald

@JoshPetrie yeah, maybe eh? My first choice might still be SF, but second and third choices would be Google Code and Git Hub in some order

With no fourth choice at all

.. yeah, I should migrate all of my code to Google Code. It's been great so far

Not treating me like an idiot

Raven Dreamer

4:52 AM

Well this is amusing.

I forgot to check for the width of platforms in my falling code.

Infinite width platforms for everyone!

Cyclops

12:44 PM

@jonathanconnell, comm test, do you read me? :)

Jonathan Connell

hey

How goes it?

Cyclops

greetings - I guess you saw my note about the duplicates being cross-site, so not mattering?

also - meta.gamedev - downvotes don't matter, your karma doesn't change. It's only a reflection of your main gamedev.com score

Jonathan Connell

I still think it's a strange way to handle duplicates

Cyclops

well, duplicates across several dozen sites are a bit harder to moderate. :)

Jonathan Connell

Although people would probably be miffed if their answers were deleted and they lost points.

Cyclops

12:47 PM

ah, you meant single-site duplicates. Yeah, I think once a question is closed, votes shouldn't count. Ah well...

Jonathan Connell

Well, at least the rules are well defined so we know what we're dealing with

Cyclops

if you saw my last update - it is still possible to make it CW, but I don't think it's worth the effort, myself. my one up-vote cancels two downvotes, so your rep should be okay.

Jonathan Connell

I'm not actually worried about my rep to be honest

Cyclops

Also, one minor point - if you want to avoid duplicating cross-site - it's always worth checking the main meta site - nearly everything you could think of has already been asked there.

Jonathan Connell

I just think it's strange not being able to delete, and still getting down-votes once the question is closed.

!Thanks, will do

Cyclops

12:49 PM

yeah, it's a pain, but there are lots of glitches in the system. :) Such is life...

I was going to suggest you could post on the main meta, suggesting it be changed - but someone probably has already posted the same thing. :)

And I already know their reply - "even for closed questions, people who find them in the future will judge the quality, based on votes - so votes are still allowed... " :)

Anyway, I'm off, cya.

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