Monday, October 28, 2013

Game 5: "Word Origami"

Last week we took the week off. Even doing what we love 12 hours a day gets exhausting after a month. So we read, rode our bike and chilled. Easy to do on Bali.

Today we started our 5th game. It's going to be a Boggle style word game. The challenges are finding a good word list, creating good game boards from it and the networking code. The rest is mostly UI work.

The word list was especially worrisome since it's completely out of our control. We need a high quality, large word list that's in public domain. So I spent a few hours googling and found not one but several good word lists. In fact, most of the word games use one of these word lists - ENABLE2K by Alan Beale. Scrabble's official word list is also in public domain!

Also not infrequently lately I've been getting into "the flow" while writing a game. "The flow" is this state of being where everything is lucid and easy. Read the book by Mihaly Csikszentmihalyi for more info. This means that I am becoming proficient enough in Corona SDK, and that was one of my goals for this project. Me happy!

Thursday, October 24, 2013

Where is all the open source Art?

Code - side:
The world pretty much runs on open source software, - Linux, Apache, MySQL, Memcached, ... the list is endless. Almost every company with any meaningful tech is using some open source software. Some of the best software developers invest countless hours of their time into open source movement; it's a point of pride for them.

Art - side:
The open sourced art is pathetic! It's a tiny selection and of poor quality. Whenever you see open sourced art, such as on, there is almost invariably a demand to put the name of the artist in the credits. If your average website had to put in the credits the names of all the contributors to all of the softwares it's using, that list would thousands names long.

WTF is going on? Do software developers in general have generous hearts, while artists have poor hearts? Do software developers live in a world of abundance where sharing is the norm, while artists live in a world of scarcity where hoarding is the norm? Do software developers earn so much for their work that they can afford to share, while artists are paid so little that they need to squeeze every last penny out of their art? Is there some systemic issue at work here? I would like to understand what's going on here.

Monday, October 21, 2013

Game 4: "RunJumpDuck" released!

And we are done with game #4 - "RunJumpDuck". We tried to make a martial arts style platformer this week. It was MUCH harder than expected. By far the hardest genre we attempted so far for both of us. So what we have now at the end of a week is not a game yet, it's a prototype. Here is a video:

I love platformers and they seemed easy to make. Man was I wrong. Five days into the this game I had nothing to show, and Liza had nothing to show. We were both banging our heads at the buggy, poorly documented, awkward softwares and tools. But let me start a few days before that.

Last Monday we sat down to brainstorm the game design. There are a few good platformers in App Store, such as League of Evil and Fancy Pants. I really like the avatar action in Fancy Pants, so I wanted to make a platformer with similarly evocative movements and precise controls. The level design we decided to do using tiles, because we could iterate on them much faster than if using hand drawn levels. And given my martial arts background I wanted to have a martial arts theme.

One obvious question is how to design levels for a platformer. For our previous games, all level design was stored in the code. But for this game that wouldn't work, - levels are big, varied, with lots of unique details. So I needed a level editor. There are a few options: LevelHelper which reportedly is very buggy, another editor only for Windows, and the open sourced Tiled. Not much to choose from, Tiled was really the only option. But Tiled has poor documentation, and on the Mac obtuse and buggy UI.

So I made a level in Tiled that is saved as xml or json. But the game needs to read in this data, display it, move the camera, etc. No way I could write all this code in a week. Thankfully when using Corona SDK there are a couple of options here as well: Ceramic Tile Engine and Million Tiles Engine (MTE). The former is open source (awesome!), beta release, while the latter is inexpensive, proprietary, also beta release but more fully featured. I went with MTE for its features. The engine is nice, the developer very responsive in the forums, but it's still a beta quality software with an occasional bug and sparse documentation.

It took a couple of days to get my first attempt at a level to display on the phone. And just when I thought things would get straightforward and easy, they got MUCH harder:

A platformer needs physics to simulate the dynamics of the game. Some folks write their own physics engine, but I thought why waste time when a great physics engine Box2D is bundled with Corona? ... In a couple of days I would pulling my hair out in frustration at Box2D. Here is a sample of issues I ran into:

  • There is a fundamental flaw in Box2D that sometimes can abruptly stop a polygon (e.g. an avatar physical shape) sliding on smooth surfaces (e.g. ground) made of several tiles. Took two days to solve. I posted the solution here.
  • Avatar needs different physical shapes in different postures, eg. walking versus sliding. Changing shapes midway can make the avatar fall through solid ground. Solution requires very careful positioning of physical bodies in relation to each other.
  • Flickering tile edges because of scaling. Solved by extruding tiles by 1 pixel, and completely redoing the tilesets and the level map.
  • Fully testing the game in the simulator using the mouse is impossible. And hooking up key events to the simulator on Mac requires a paid subscription to Corona Pro.
  • ...
All of these are well known problems in making a platformer. But as a new comer to the genre, these were a little too much to solve in just one week.

These were my woes this week. Liza had just as many of her own:

Art for a tiled platformer consists of three parts: a tileset for levels, UI and avatar/NPC spritesheets. Way too much for one week. So we decided to buy the level tileset and the UI, while Liza focused on learning to animate characters. It's a story of obtuse, poorly documented software. She tried two inverse kinematics animation softwares: Spine and Flash. Both sucked. Out of seven days she spent five fighting the softwares, and only two animating.

I love the white ninja that Liza animated. And this is her first try at animating ever! There are many more animations she did that are not shown in the video above. I hope they will see light one day.

So in the end I am impressed that we were able to put together even a basic prototype. But the full game would take a few more months to develop.

P.S. And I can't post the source code because I am using proprietary engine MTE and licensed tilesets :(

Monday, October 14, 2013

Resources: Source Code, Art, FX, Editors, Sound

This will be an updated page with links to free or inexpensive art and sound game assets.

Learning Corona:

Level Editors:

Game 3: "Oog" Released

Game #3 is done! It was a lot of fun to figure out the physics for it, the bodies, the joints. I am amazed at how interesting the game play becomes with the addition of physics. It really makes for emergent gameplay. Here is a video of it:

As usual, I am releasing the code into open source under MIT license. The art and sounds are for your personal use only (I would love to release these into open source too, but bits and pieces of them were bought from the stocks, and come with their own licenses, and I would have no idea how to untangle that legal mess, so for your personal use only.)

I didn't find this game particularly challenging to make. Corona SDK and the physics engine Box2D do all the heavy lifting. Man, I feel like a spokesperson for them; I am not, really :)

I used Physics Editor to get the polygonal shapes for the hilly ground. Good tool. And we also use Texture Packer made by the same folks.

Liza learned a ton this week. She did all the glorious animations of Oogs frame by frame! Great personality in the little creatures.

We are both looking forward to making a full physics puzzler out of this prototype. The World of Goo was an inspiration for this game, but there is a lot of unexplored gameplay left that would make for a few more amazing games in this genre.

Monday, October 7, 2013

Game 3: "Goo"

Today is Monday, and we kicked off the development of our third mobile game. This time we want to make a physics puzzler. This genre has some really excellent games such as Angry Birds, Cut the Rope, Where is My Water, Contre Jour.

We sat in the cafe early morning today discussing different original ideas for the game design, and none of them clicked. But we both really like blobby things, they are fun to play with. So we decided as a learning experience to make a clone of an amazing game - World of Goo.

As of right now, I know almost nothing about building physics games. Gooey physics is particularly challenging because it is so deformable. Actually, I don't know if a game like this is even possible in Corona SDK. And if it's possible to make in a week (not the whole thing obviously, just a couple of levels). We shall see soon enough...

Sunday, October 6, 2013

Game 2: "TV Slots" released!

Alright! And we are done with game #2 - "TV Slots". This game was harder to make for both of us, took the whole 7 days. Here is a video:

We are releasing the code into open source. Enjoy! :)

I ran into two challenges while developing this game:
  1. Getting the reels scrolling realistically. The basic idea is to place two copies of each reel on top of each other and scroll both downwards. When the lower part scrolls below the viewport, translate it above the upper part (so it becomes the new upper part and the old upper part becomes the lower part). Easier said then done. I spent a couple of days getting all the scrolling working well.
  2. The reel design. This is a whole science in itself. There are folks selling software to analyze reel design for unlisted prices, I imagine in tens of thousands of $$$. Our design:

I continue being impressed with how easy it is to make games with Corona. Seemingly hard things are just trivial. For example, midway through the week, we had an idea for a simple action game based on physics. It took all of two hours to make a prototype, including reading a tutorial on making physics games )

I am noticing that a lot of the code is replicated from game to game: level selectors, player data, game data, UI, load screens, iap, experience, stars, etc. I can see how in a few months I will end up with a generic game template that takes care of all the boilerplate.

Wednesday, October 2, 2013

Fonts for games

To make our game look better and uniform across devices, we want to use a nice embedded font. It's easy to do with Corona, just add the font file to the directory and specify it's name in a config.

The problem we just ran into is acquiring the fonts. I didn't know much about typography until now. Well it turns out there are thousands of font designers the world over making beautiful fonts and charging ludicrous prices. The first search yielded font shops selling fonts for $1,000-$10,000 per app. Who would ever buy these?!? The value that a great font adds to the game is, say, 5%. So to justify these font prices, the game must make $20K - $200K. There are very few games earning that much.

So a heated conversation about the craziness of this world later, we returned to google to find several collections of free fonts. God bless the open source.
Great looking fonts too!

Also useful discovery are these lists of fonts that come with iOS: