My current project: Soc-car

witnessmenow

Hey Guys,

I thought this might be a good place to kind of write up what I'm up to at the moment.

Just a bit of a background: I'm a developer (working for about 4 years) and have worked with a good few different languages, but never with games.

So for a long time I've had a hankering to make a game, actually I see that there is a talk of a boards made game, I made the thread for the first one (that fell on its arse )

So the game I want to make : basically think air hockey, but instead of paddles you are controlling cars.

Funnily enough looking through the earlier boards game thread I actually even had that idea back then!

The working title, Pro Igo is a throw back to Top Gear soccer and Pro Evolution.

So I made a start on this the a couple off weeks ago using Libgdx and Box2d

I found an example of a top down car POC and have adapted it from there

So currently I have two cars, a ball, a pitch and Goal detection, So its "playable". If anyone wants to try the current version you can grab it here.

You need to hava java installed. IF you have a "JAVA_HOME" env variable you can just click the bat file. Else just type the following in cmd "java -jar LinkTo.jar"

Code is available on my Github.

I'll try post progress updates as often as I am making progress! In the mean time I would love to hear any suggestions or ideas for it. If anyone has any questions I'll do my best to answer.

witnessmenow

Finally got the sprites going last night. Also spent a couple of hours trying to do a HTML 5 build last night and it didnt seem to be working for me, will need revisit that.

For the sprites there isn't actually that much work involved (just took me a while to figure it out)

Where to put the images:
First off is where to put the images where they are accessible. (Note: I used the Maven Arch type that libgdx provides to set up my project so it might not be the same for everyone)

For me, under the desktop project I have an assets folder. As part of all the other projects maven build it will copy that assets folder so it should be accessible for all different build types. So put your images there.

Creating the images
So texture images apparently need to be to the power of 2 in size (16x64, 64x64 etc) so keep that in mind. Dont worry if the body you want to cover is a different size to that (say 10x20), just make the image file 16x64 put but your "art" in a 10x20 space inside the file, as you will be able to address certain regions of the image. You can use this to have multiple animations or different sprites on the one image file. For example here is my cars image file



What size should the image be?
So know how to create the image file, but what size should it be?

well basically its the size of your box2d object multiplied by the "PIXELS_PER_METER" that is probably defined in your main game class. e.g. my cars are 2x4 boxes and my PIXELS_PER_METER is 10 so my images needed to be 20x40. I decided to put 3 cars on the one image, for no particular reason really

How do I turn a texture into a sprite?

First thing you need to do is load your texture:

this.carTexture = new Texture(Gdx.files.internal("NewCars.png"));

Where "NewCars.png" is in my assets folder under the desktop project. Then you create a sprite out of it:

return new Sprite(ballTexture,
							0,  //X
							0,  //Y
							40, //Width
							40 //Height
							);

So X and Y are the co-ords that your image starts from (0,0 is the top left of the image) and the width and height are how many pixels your region should be. In the car example above I use the following function to return the cars:

//0=blue,1=red,2=green
	public Sprite getCarSprite(int colour)
	{
		//limit to max number of cars
		if(colour < 0 || colour > 2)
			colour = 0;

		return new Sprite(carTexture,(20*colour),0,20, 40);
	}

How to attach it to the body

So basically every time a render/game loop happens you need to update the image so it is still on top of your box2d prop.

So in your main game class you need to have a SpriteBatch property, initilise it in your create method:

spriteBatch = new SpriteBatch();

In your render loop you need yo update the spriteBatch with the camera (my camera doesnt move so I dont really know whats happening with this)

spriteBatch.setProjectionMatrix(camera.combined);

After the you have updated the positions of your bodies you then need overlay the image on the body.

So start the batch, update the sprite locations and end the batch.

		this.spriteBatch.begin();
		//Update Player/Car 1

		player1.updateSprite(spriteBatch, PIXELS_PER_METER);

		//Update Player/Car 2
		player2.updateSprite(spriteBatch, PIXELS_PER_METER);

		//Update Ball
		SpriteHelper.updateSprite(ball.sprite, spriteBatch, PIXELS_PER_METER, ball.body);

		this.spriteBatch.end();

So I guess the above is a little confusing. Player1 and Player2 are Car objects. They have a method "updateSprite". SpriteHelper is a helper class, it has a static method "updateSprite". The Car object in turn calls the SpriteHelper Class for its self, and then gets each of its 4 wheels to update their sprite.

So here is the updateSprite code in the helper class:

public static void updateSprite(Sprite sprite, SpriteBatch spriteBatch, int PIXELS_PER_METER, Body body)
	{
		setSpritePosition(sprite, PIXELS_PER_METER, body);

		sprite.draw(spriteBatch);
	}

	public static void setSpritePosition(Sprite sprite, int PIXELS_PER_METER, Body body)
	{

		sprite.setPosition(PIXELS_PER_METER * body.getPosition().x - sprite.getWidth()/2,
				PIXELS_PER_METER * body.getPosition().y  - sprite.getHeight()/2);
		sprite.setRotation((MathUtils.radiansToDegrees * body.getAngle()));
	}

so setSpritePosition is the interesting thing here. You need to get the X and Y co-ords of where you want the image to go.

PIXELS_PER_METER * body.getPosition().x will get you the x co-ord for the center of the body (same thing for y), but to make the image correctly overlap we need to take away half the sprite width.

Take this example:

if you had a 4x4 box, the center point would be 2,2

If you want to overlay a 4x4 image on it, there is no point putting it on 2,2 as remeber when i said earlier that the top left of an image is 0,0 so thats where it starts. if you set the sprites location to 2x2 it will only cover the bottom right corner of the box. So in this example you want it to start at 0,0

Just a heads up, you might need to play a little with the images rotation, the first couple of times I had it wrong. To be honest I havent fully figured out that, im just trial and erroring it.

I'll do a build and stick it up later so you can see my beautiful art work

If you need more info see if you can follow the code in my Github link in the OP. The ball is an easier example than the car I'd say

RedXIV

This is awesome dude, exactly the type of thing we need to see more of here

I'll take a look tonight properly when I'm not in work

Retr0gamer

If you wanted a weird shaped sprite could you not make a composite sprite made of different 16x16 sprites that overlap...

Actually that kind of sounds like a pain in the hoop to animate.

witnessmenow

Retr0gamer wrote: »

If you wanted a weird shaped sprite could you not make a composite sprite made of different 16x16 sprites that overlap...

Actually that kind of sounds like a pain in the hoop to animate.

You probably could. Remember as well that you can use transparent pixels for strange shaped objects e.g. my ball texture is is a 20 pixel radius circle in a 40x40 box and anything outside the circle is transparent, so I just treat the sprite as a square.

I was looking at the video for RUBE yesterday and it looked really interesting. If you had complex objects it looks like it would be well worth it.

There was another thing I came across that looked useful too: Physics Body Editor it kind of reverses the approach, you start with the image and create a object from there.

hooradiation

Retr0gamer wrote: »

If you wanted a weird shaped sprite could you not make a composite sprite made of different 16x16 sprites that overlap...

Actually that kind of sounds like a pain in the hoop to animate.

Not really.

You could use a node based system.
One sprite is the root of the overall image and all other sprites are attached to this.
Then every other item has it's position defined relative to their parent node, therefore moving them is easy.

(i assume you mean moving rather than animating, given so far there's only been talk of moving items around the screen. Animations would be separate to that, but also easy to implement under such a system)

Kyotokid

Nice.

Is it possible to alter the shape of the cars? Maybe bring the two verts at the front of the car closer together to make a trapezoid. Then the 'pointy' narrow face becomes the front of the car.

I want to see how well I can control both cars simultaneously

witnessmenow

Kyotokid wrote: »

Nice.

Is it possible to alter the shape of the cars? Maybe bring the two verts at the front of the car closer together to make a trapezoid. Then the 'pointy' narrow face becomes the front of the car.

I want to see how well I can control both cars simultaneously

Thanks That build is old enough now, I'll update it this evening. I really need to sort out the HTML5 version as that would be much easier to share.

Yeah I believe it is, you would just attach a triangle to the front I guess. I think you use what is known as a "Joint" in box2d to attach two shapes. A pointy front would make it very hard to control your shots I think

If you you look at the video for RUBE you can pretty much make whatever shape you want.

My girlfriend actually found a bug in it (kinda) the other day. My laptop only seems to allow 3 or 4 key presses at one time (I think this is a common thing, "frets on fire" suffered from the same issue, its a hardware problem with the keyboard). so she figured she could stop me being able to control my car just by holding down a few keys.

So I'm going to try set up controller support on it this evening (360 controllers), and possible make it 4 player

Kyotokid

Oh if altering the shape affects the physics (and is not *just* a graphical thing) then I agree; don't do that

witnessmenow

I merged the code from DGC lat night and re-factored it to within an inch of its life

I really have a taste for Game dev now, and me and a couple of buddies are going to see how far we can bring this game. (would be an absolute dream to get this even somewhat popular)

So towards the end of the week I'm going to fork the repo into a private repo. That means that all the code and changes up to this point will still be visible, but anything that happens after that will be on a different private repo.

I will provide a build where you can change the number of players between 2 and 4 so it is basically a playable version of what was done at Game craft (the actual build from DGC pretty much requires you to have 4 wireless xbox controllers )

I'll still update this when I come across things I think would be interesting to others.

witnessmenow

This is the merged and refactored version of the game:

Some things to note:

4 players only works if you have at least two Xbox controls (probably only wireless ones too!)

If you have any controllers they will be added to the pool (only xbox controllers are configured to work though!). 2 repeating keyboard controls are added twice like this:

left,right, up, down
a,d,w,s
left,right, up, down
a,d,w,s

cars will take their controls starting from the top of the pool

So unless you have two xbox controllers you will be controlling two cars.

Pressing f3 changes the number of cars to 2

witnessmenow

Got the game running on my Ouya last night, runs great! not too much involved to be honest, installing the driver for the OUYA is the most complicated part

witnessmenow

Just to give a bit of an update on this:

I'm hoping to release on Ouya at the end of the month (in time for the official Ouya release)

I'm not happy with the name, so currently it doesn't have one :P

I've been working fairly hard at it since DGC, even in this nice weather (its tough!).

Let this be a warning to anyone making a game, there is a lot of slog work you need to get through to actually release a game.

The core game has barley changed since DGC, I have just been working on making controller support more solid (especially for the Ouya) and menus, bloody menus!

There is so much crap you don't think about.

I guess once you have that kind of stuff done for one game you could re-use it though.

Currently the game consumes my thoughts! As I work a day job I normally work on the game at night, so its stuck in my head when I go to bed. I think there will be a big weight of my mind once I get V1 out, even if it tanks.

Every time my girlfirend tells me its just a game :pac::

witnessmenow

So I released this under a new name on the Ouya

Its now called Soc-Car



Here are some screen shots

Soc-Car is a local multi-player game where you control cars playing a game of soccer. It's 2-4 players (You can also mess around with one player)
The game supports Ouya, Xbox and Ps3 controllers.
Phones and tablets are also supported without the need for external apps, using a free open source library I'm working on called "More Controllers Please". If you are interested in adding MCP to your game please get in touch and I can help you.

There is not really too much I can say here other than if you have some friends over please give it a try, its 100% free and is only about 5Mb of a download.

Here is a boards exclusive Pc version, for some reason its a good bit bigger! (10mb)

Should work with Xbox 360 controllers, 2 players on keyboard (arrow keys and awsd) also you can connect your phone or tablet up to use it as a controller (select "More Controllers?" for more info)

I would love to hear any feedback you have.

Thanks

witnessmenow

Someone created a Video review

https://www.youtube.com/watch?v=TbKd1yQSb2w

Its not overly positive, but its really nice to see someone taking time to make the video!

Mr E

He's a moron. He gave a multiplayer game 2 stars after playing by himself for a few minutes.

It looks like a sound game and would be much more fun with a second player. Physics seem good too. Well done!

Kilgore__Trout

Had a quick blast on it in solo. Seems quite fun, but like Micro-machines, think it would work best with a crowd! It didn't recognise my faux xbox 360 controller. Thought maybe the turning on the cars wasn't sharp enough, but it's kinda hard to judge without getting a proper game going.

It's an odd concept (cars and football) and could actually be a pretty good fun with a few mates. Good work!

witnessmenow

Kilgore__Trout wrote: »

Had a quick blast on it in solo. Seems quite fun, but like Micro-machines, think it would work best with a crowd! It didn't recognise my faux xbox 360 controller. Thought maybe the turning on the cars wasn't sharp enough, but it's kinda hard to judge without getting a proper game going.

It's an odd concept (cars and football) and could actually be a pretty good fun with a few mates. Good work!

Thanks!

Yeah to be honest the pc version requires a bit of TLC, it only really supports 360 controllers (I guess real ones too!). I was concentrating on the ouya version mostly, although it is great being able to try out changes on the pc quickly.

The ouya version accepts Ps3, xbox and Ouya controllers.

I think the next major work I do on it will be AI, its just too rare to have buddies over to play games unfortunately!

Kilgore__Trout

Turns out it didn't recognise the controller because I had Unity open. Working fine now!

Maybe you could tell us a bit about the development?

witnessmenow

Kilgore__Trout wrote: »

Turns out it didn't recognise the controller because I had Unity open. Working fine now!

Maybe you could tell us a bit about the development?

EDIT: Im also after thinking, the controller needs to be plugged in before you launch the game (I know, not great!)

I would love to! What about it would you like to know?

Kilgore__Trout

Well mainly I'd like to know about tech used, team size, and how long it took. Also, if you learned any difficult lessons during development : )

witnessmenow

So it is built using LibGDX (so Java is the language) and Libgdx's integrated Box2d for physics.

The only other external library I'm using is my own , "More Controllers Please", that is for using tablets and phones as a controller. To be honest, although its usable, it is not best. I do seeing having potential, but maybe not for this game

The development team is mostly me, but I get a dig out from a few friends.
There is also an artist involved too, but he has been quite busy lately so hasnt got to do too much, which ment I had to get my artist gloves on! (I think its pretty obvious what I did and what he did)

Valuable lessons would be the time it takes:
I have been working on it for about 3 months. If you play the demo i posted in some of the original posts, the game play really hasn't changed much. I had a playable POC working in a couple of weeks, its the "polish" that really takes time. Menu systems etc take a lot more time than you think, and they are also not very interesting to work on. I found it really tough for a couple of weeks where I was writing menus.

And saying that, the game needs way more polish!

Another thing, I wont say i learnt, because I already knew, is that you severely limit your target audience with a local multi player only game. Online would be great but there is a very large commitment I think to get it right.

The last thing I would say is, side project development is really tough in general, It really does consume you. I have an hour commute to work each way and I'm nearly constantly thinking of the game or MCP. While this isnt my first side project to do, it is by far the largest scope. There is probably more lines of code to handle the menus than there is in the entire checkargos.com site! But i think it really has impaired my ability to relax!

Starting game development coincided (probably not by chance) with me tearing my ankle ligaments. This has still not fully healed so I have not been able to exercise as much as I should be. While this does allow for more free time to work on the game, it probably has much larger negative effect on my work/sideproject/life balance. It will be interesting to see what impact on devopment me returning to exercise has (that isnt really game dev related though)

Kilgore__Trout

Thanks, nice to get a perspective on how it works for someone else. What would you guestimate the number of hours you put in as? Few hundred?

I've had a lot of similar experiences with development. I'm almost 7 months in and I've been saying "Ah it'll only take another 2 months" (usually at least once a day) for the past 4 months.

I'd say my GUI has gone through 5 - 6 revisions and runs to almost 4,000 lines. Probably 2 - 3 weeks right there. (Really must look into buying some middleware : )

Also in a similar position re multiplayer. Local is a possible stretch target (perhaps after release), but online MP seems pretty daunting. The life balance is tough to get too. I try to get in some exercise everyday, make a decent meal, and get an hour or two of recreation, but it's a long haul and I have a tendency to get consumed by it.

Anyway, here's to making games and not going insane/withering away/becoming a recluse

witnessmenow

Came across another review yesterday

https://www.youtube.com/watch?v=uukR2YDzIyQ

They rated it a "hidden treasure" (on their "hidden treasure" or "cat poop" scale). Although they did rate "No Brakes Valet" cat poop and that is a vastly more popular game than mine so maybe its flawed :P

As I said earlier there is something really cool about someone taking the time to record themselves playing the game. It gives a real boost and motivation to work on it!

witnessmenow

Its been a while, but I'm back working on this! And I'm about to give it its third and hopefully final name change!

Haven't fully set on a name yet, but the reason I'm changing it is that I'm adding more non soccer game modes.

So changes from the version in the videos above:

I've changed the resolution of the game to be 1080p (previously was 900p)

Re-adjusted the sizes of the cars, which allowed the artist to create bigger sprites





A common complaint in the last version was identifying what car you are, I've added identifier circles under the cars. I'm not overly mad about the look of them, but they serve a purpose.

Another feature people requested was a handbreak, I have kinda addressed this by adding a button that reduces your speed but also your turning circle, so hopefully helps

Another thing people wanted was AI. So started on that this week. currently have a pretty dumb guy going who just chases the ball, and trys to right himself if he gets stuck in a wall or whatever.

Will post more updates later, and hopefully will have a demo shortly

Kilgore__Trout

Guessing the AI will be tricky... figuring out what direction to punt the ball and so forth.

The cars looks nicer now btw. Good luck

witnessmenow

Kilgore__Trout wrote: »

Guessing the AI will be tricky... figuring out what direction to punt the ball and so forth.

The cars looks nicer now btw. Good luck

Thanks!

I think with a small bit of modification they way it is now isn't that bad. TBH the game is a little bit more random than skill based so blindly hitting the ball isn't the end of the world... unless the ball is behind you (in terms of your goals). Once I have it coded that the computer tries to get goal side of the ball when its behind it will actually be relatively playable I'd imagine.

So currently on every game tick the AI tries to match the angle the car is facing with the relative angle made between the center of the car and the ball

so if the ball is on the same y axis but its to the left, the relative angle would be 180

if the car is facing the same angle and driving forward it will hit the ball, as even if the ball was moving the relative angle would be adjusted to suit on each game tick.

I might actually try put up a post on designing the AI. I'm currently not following any guides or anything (probably a bad idea!) so what I would post up, I have no idea if its good practice or anything!

witnessmenow

So I have put out a demo of the game this evening.

There is a desktop version and an Ouya/Android Phone version

If anyone had any comments or feedback I'd love to hear it!

I will say as little as possible about the game as hopefully it can be figured out from in game instructions. But some things to note:

No indication that you have added AI
No Sound at the moment
No Pause
Temp Score board on soccer screen
No indication that a goal is scored in the soccer level (it will restart 5 seconds after a goal is scored)
Cars not yet pottable in the pool level

Some Screen shots:

Kilgore__Trout

Had a go last night. Looks a lot better since last tried it. The AI seemed very good at potting the balls in the pool game.

Couple of suggestions:

1) Adding AIs is a little confusing. I wasn't sure if I had to take control of the cars and drive them into the team areas by pressing B, or they were just added. Adding a sound when an AI is added and updating the number of cars in each team would help clarify this. Could show the number of players and AI in separately like Home: (Players) + (A.I.)

2) Might be an idea to experiment with different car/ball/goal sizes to see how it affects the game. Might increase game length, and might make it easier for your AI cars to navigate around it.

3) Music would be good, but I understand you might want to add a credits screen first so you can credit the composer. Incompetech.com has a lot of music, which is free so long as you attribute it. Same for sound effects, but you might want to keep them more in the background (or enforce a minimum time between sounds), as repetitive sounds can get on player's nerves.

4) Consider restricting the max number of cars that can be in a map. In my first game, wasn't sure if AI was being added. This was the result

5) If you're going for a party style game, with numerous sub games, you could think about a demolition derby mode, and a mode where a flag randomly appears, is picked up by a player, who then gets scored on the amount of time they can avoid other players.

Anyway, it's coming along nicely. Looking forward to future updates.

witnessmenow

Kilgore__Trout wrote: »

Had a go last night. Looks a lot better since last tried it. The AI seemed very good at potting the balls in the pool game.

Couple of suggestions:

1) Adding AIs is a little confusing. I wasn't sure if I had to take control of the cars and drive them into the team areas by pressing B, or they were just added. Adding a sound when an AI is added and updating the number of cars in each team would help clarify this. Could show the number of players and AI in separately like Home: (Players) + (A.I.)

2) Might be an idea to experiment with different car/ball/goal sizes to see how it affects the game. Might increase game length, and might make it easier for your AI cars to navigate around it.

3) Music would be good, but I understand you might want to add a credits screen first so you can credit the composer. Incompetech.com has a lot of music, which is free so long as you attribute it. Same for sound effects, but you might want to keep them more in the background (or enforce a minimum time between sounds), as repetitive sounds can get on player's nerves.

4) Consider restricting the max number of cars that can be in a map. In my first game, wasn't sure if AI was being added. This was the result

5) If you're going for a party style game, with numerous sub games, you could think about a demolition derby mode, and a mode where a flag randomly appears, is picked up by a player, who then gets scored on the amount of time they can avoid other players.

Anyway, it's coming along nicely. Looking forward to future updates.

Hey,

Thanks alot for playing and the feedback!

You know whats funny about the AI in the pool game, they are not doing anything clever.. I mean at all! They take one ball at a time and drive into it at full speed, thats it! They work really well though.

1) I'd say that demo is reasonably old, I have added a counter for AI now, its still awful way of adding though! and still no way of removing them other than restarting the game... awful! Will definitely change.

2) Yeah there is literally any number of combinations, I've tried lots and that was the best I've came up with so far! Car and ball are bigger since my original version and I think it plays better. Ball might not slow down fast enough though.. may look into that.

3) Yeah I used him in my original game for the menus too, as you know your self probably, adding the music and sound effects is no hassle at all. Finding the right stuff is the issue! You are right re attribution as well, without a credits screen I didnt want to add anything I didnt have rights to use. I will visit sound for sure after the menus are done.

4) I probably should When I change the way AI is added I'll limit it there. I'm surprised how well it plays even with a stupid amount of cars though!

5) Lots of people are asking for Destruction Derby, really not sure how to calculate the damage though! Hopefully I'll figure something out! I think that second idea is great and should be easy to implement, thanks!

I've implemented a few new game modes since that demo too, there are some screens shots here

I'll throw up a new demo soon. Thanks for playing!

witnessmenow

Here is the latest version of the demo, from a UX point not much has changed, but there are now 6 mini games (not all of them are fully finished though, but they are playable)

You can find it here:
https://db.tt/GwfQfdHS