My Work

Gameplay3D on Android

2013-04-14T11:22:00.001-07:00

I've experimented with the Gameplay3d engine by the good folks at blackberry and found it really fun to work with. There are still some kinks to be worked out about the workflow for the materials but over all the experience has been good.

Today i've managed to get them some demos running on my device.. here are the screen shots..
Here are the steps to get the apps on to the device..

cd /android
$ANDROID_SDK_ROOT/toos/android update project -t "android-10" -p . -s
$ANDROID_NDK_ROOT/ndk-build
ant debug install

Space Ship Sample from Gameplay src

A Sample 3D application ive' developed using Gameplay

The takeaway would be that.. if you are looking for a good free 3D engine to start off something Gameplay might be a good place to start, especially if you are familiar with OpenGL and GLSL shaders.

GamePlay Engine

2013-03-23T12:56:00.001-07:00

I came across GamePlay engine a while ago. It claims to be easy to pickup for people who have worked on cocos2d-x or similar libraries. I doubted that claim and was too full of myself to give it a go. After all i already have a class for loading 3D models in cocos2D-x.

Over the weekend i wanted to give it a go just to get a feel for how things work in GamePlay engine. Im' happy to report that It was pretty awesome and would definitely give it a go if i had to pick up a free 3D engine to work on a game.

There were a few things that threw me off though, took me a while to figure out what was going on..
my first hurdle was to fix the Xcode projects..

The missing Frameworks?

So the projects were all the basic stuff required for an app but the xcode projects from GamePlay were showing them as missing... so basically i just had to drag drop them from finder window to the project tree. Easy but lost a lot of time trying to figure this out, Basically lack of documentation / troubleshooting documents.

The best thing about the engine is that you can directly import collada(.dae) files to the scene by converting them to ".gpb" gameplay binary. This is done using "gameplay-encoder" tool. The thing is you have to spend some time trying to understand the samples provided with the source code. I quickly realized that i had to look at the samples and analyze the code rather than searching online with weird questions. I have really not checked the forums but i would definitely look at the samples before even looking elsewhere.

The UI can be created in a pretty straightforward way, just specify the control type, location, alignment etc. The usage is simple once you figure out the syntax and get used to the Framework. The one thing i struggled for in this mini project was figuring how to set the light and the material of objects.

The awesome Rotating Cube

The scene is easy to setup, accessing different nodes in the scene based on their name is easy and so is setting their properties. Importing material data is one painful thing right now, which i hope will be fixed soon. As per actual game to be made, with the default physics integration it should be easy but i can imagine it not being as easy as say.. using unity for doing the same. The engine does support lua scripting .. which im' still yet to try.

Cut Thy Polygon

2013-02-16T20:27:00.001-08:00

Fruit Ninja is an awesome game.. very addictive.. and fun to play.. but if you observe carefully you will see that where ever you slash the fruit.. it is always cut in half.. It is a simple trick to keep things nice and fast. But imagine if you could cut and slice a fruit every which way you wanted precisely the way you wanted.. this is an idea i had for a while..

Slicing enemies into pieces based on slashes.
Slicing fruits based on the slashs
Creating predefined shapes from a starting shape

and the list goes on.. and it all starts with a line intersecting a polygon and the polygon being cut into two polygons. Before we go any further here are the screens of how the result will look.

After 1 cut

After two cuts

After 3 Cuts

Now lets get to the most important part.. Cutting a polygon into two pieces.

For each Edge in the polygon:
if Cut bisects Edge
Find point of intersection of Cut line and Edge of polygon.
Add V0 of Edge to left polygon or right polygon based on whether it lies to left / right of Cut line.
Add V1 of Edge to left polygon or right polygon based on which side it lies on to the Cut line.
Add the Intersection Point to Left and Right polygons' vertex list.
else
Find which side the Edge lies on to the Cut.
Add the V0 and V1 of Edge to the corresponding polygon's vertex list.

Once you have done this we have two vertex lists one for the polygon to the right of the Cut and one to the left of the Cut. All we have to do now is to create polygon objects from the new vertices so they can be cut further.
I've been working a lot with Cocos2d-x recently so i've implemented it the same.. here is the archive of classes directory for the cocos2d-x project. http://cocos2d-x.org/attachments/1767/PolygonCutting.zip

Screenshots of what you get when you run it..

The initial polygon in white, you can draw arbitrary lines to cut the polygon along that line. The newly created polygons are drawn in red and yellow.

Adrian lives On

2012-12-13T18:03:00.000-08:00

I have been wondering what will happen to Adrian after a while.. We haven't really worked on making it better or ported it to any new platforms. Fortunately for us some people still take time to port our game to the platform of their choice.
http://www.arosworld.org/news.php?readmore=213

I never heard of aros before but that is the point... The game lives on. Would love to see more of such things happen...port for chrome would be awesome.. :)

Anim3D

2012-11-12T07:59:00.000-08:00

The simplest way to create a 3D animation is to create multiple keyframes (3D meshes) for different timeframes and interpolating the vertices with time. This is the technique used for Quake2/Quake3 models. The simplest file format would be to start with Quake2's md2 file format. The problem though is that there aren't many exporters around for the format and the loaders that are around seem to screw something up something regarding how the animation is handled.

I could have spent some time to figure this out and fixed the exporters/written one myself.. but i thought it would be a good learning experience to try writing something myself. That's how the 3danim project started. Just one simple ascii based file format that is easy to parse and use. I didn't make it binary as thats' the logical extension for how we store the data, But the important part is to understand everything that is stored in the file.

Iv'e written Loaders in c, python and have had my friend write the java loader. The exporter however is based on python and is an addon for the open source 3d authoring tool blender.

That is where the pain starts actually.. the blender python api has been in so much flux that after every new release, i had to re-write the exporter... the last version i updated to was 2.57 and today ive' been struggling to get the script updated to 2.64 hopefully this will stabilize soon and ill' be able to use it more often. It's probably a wise thing to wait and use an older version before everything stabilizes..

Exp with Cocos2d-x

2012-10-29T09:58:00.001-07:00

Finally i've started working with cocos2d-x for game dev. It has proved to be really handy for getting prototypes done really fast. I hated the autopointer based implementation at first but have gradually gotten used to it. The one problem i do see is that the constant creation and deletion of objects could lead to a reduced performance. I would recommend anybody to stay away from the autopointer based approach right from the start if you are performance cautious, because re-organizing the code can be a pain.

The cocos2d-x is a really good choice if you want to go multiplatform with the game as well. The best part (in my opinion) is that you dont' have to deal with the java code for the most part, you get access to OpenGL ES so basically you can develop pretty much any game and still have the benefits of scene management and animation for things that you dont' want to care about.

There is an demo of getting 3D models rendered in cocos2D-x using the projective transformation and a little Matrix math help from the internal math library in cocos2D-x. I really hope the development of this library continues at the same pace. It's just awesome to be able to write code in c++ and still deploy on all the relevant platforms.

SVG as level description file

2012-09-07T00:38:00.002-07:00

If you ever wanted to use svg as a level editor for your HTML5 games.. here is the basic code you can use. Obviously you have to make sure that your svg file is using only rects instead of any other type if you want to use this code as is.. But its' a good basic start for getting you started. I've used the color of the rects in svg to determine how it behaves in game.. you could offload it to the editor (i.e inkscape in my case) to add properties to the rects which can be read and used to determine properties.

$.get("drawing.svg", function(res){
//loading the data from an svg file.
blocks = [];
user = null;
ball = null;

var $layer = $(res).find('g').first();
//get all the rectangles in the level and create the list.
$layer.find('rect').each(function(){
//string operations to get the color set for the block.
var fillstyle = $(this).attr("style").split(';')[0].split(':')[1];
var x, y, w, h;
x = parseInt($(this).attr('x'));
y = parseInt($(this).attr('y'));
w = parseInt($(this).attr('width'));
h = parseInt($(this).attr('height'));
if(fillstyle == "something"){
}else if(fillstyle == "something"){
}
});
});

ps:///$.get() is the jquery call, so you need jquery to run this as is.. or you could handle the xmlhttp request thing ..

ramblings about android apps

2012-05-21T21:50:00.001-07:00

i got a galaxy nexus recently and as you can imagine i was very excited and began downloading a the popular games most of them behaved fine but there were some apps and games which had services eunning in rhe background even though the app was killed.i had to go to the settings and stop them. i wouldnt bother too much if the battery wasnt effected but from what i have seen it does. i wonder why the developers would so thia on a phone app. i prefer the apps that update when i ask them to. i really hope people stop doing this service atarting frenzy in their apps.

SpaceGame 48-hr GameJAM

2012-04-15T13:32:00.000-07:00

I've participated in my first 48hr gamejam. I've technically spent a lot less time but i've managed to get a prototype up and running and im' pretty happy with the way it turned out. I would have liked to add more things but time is running out so i had to cut corners. Here are the things i wanted to accomplish: 1) Bring out the tangential learning about Gravitation. 2) Make use of the gravity (since it's a space theme). 3) Wanted to do something different with the art. The concept came pretty quickly once i just drew up a mock up screen..

The rest of it was to get the mechanics right.. I used the CAAT engine so i can focus on the game itself, and bother less about the rendering. Which did help, but i also had to spend time looking around the documentation to figure out if there was a better way of doing something i would have just coded straight.. but it did payoff.. I got a playable prototype very soon. I tried to get some artwork done with inkscape based on the concept art..

As you can see i did really basic art but im' beginning to like this style. I'ts very abstract but conveys the objects pretty well. I've uploaded a playable version at http://balaji.me/vkrishna/astrogravity/ . I haven't given the name a lot of thought but i hope it conveys the content of the game.

Online Leaderboards

2012-03-22T10:59:00.000-07:00

Iv'e been on a look out for easy to use online leaderboard services for a while now. Scoreoid.net is the latest one i came across. The best feature of using this service?.... you can use it through absolutely any platform.. and they have good documentation for all the important things http://wiki.scoreoid.net/.

I've been working on a lot of html5/javascript based games. I could have used any of the standard javascript libraries to use the scoreoid service (since it uses the cgi based implementation) but i didn't want to bring in a whole library for just a simple ajax request. So i wrote a simple javascript function to make it easy to use the service..

Following is the code for the function.

And assuming most people use JSON for response type while in js realm i've forced the function to use JSON. Using it is just making a function call and you should provide callback to handle the returned json object.

You can know the details of what to send as parameters to this function by looking at the console provided on the scoreoid website. I hope this helps people trying to get their html5 games integrated with scoreoid leaderboards. I've started using this service in colortheory and its' been good so far. Give it a try if you need some leaderboard functionality in your game.

Side Scrolling RTS

2012-03-18T16:10:00.003-07:00

A Couple of years ago one of my friends asked if it would be nice / possible to implement a 2D RTS game as a course project. I thought that was a cool idea. but never got around to finding what happened. Why am i talking about this now?.. well ive' come across the swords and soldiers game and its' just like that. I've not played it but it sure does look good. I loved the art style and the animations so much. I wanted to try and design something similar just as an exercise.. but i needed some concept art to start off.. so i worked on making some concept art for it.. im' not sure if ill' ever get around to making the actual game.. but am sure excited about making a simple rts for the experimental gameplay project "Economy" theme..

rough design for characters

Color World (in progress)

2012-03-11T17:01:00.000-07:00

Work in Progress

It's true what they say about how 80% of the work gets done in 20% of the time and the rest is spent trying to get the project done. I had a prototype of a simple puzzle game over a weekend. Then i just left it in the dark. I really liked this game because it was born out of my love for "tripple town" a simple but addictive game. I realized this was quite similar to another game i wrote SQUARED for the mozilla game dev contest. At the time i was really happy with the "art style" but now not so much.. but i did still enjoy the gameplay. With some tweaks it could be a fun game on the "touch enabled" devices. I've been working on and off this weekend on getting one of my prototypes to a presentable state.. here is a comparison..

Prototype in game Screenshot

Ive spent a lot of time today trying to find the right service for getting the leaderboard up. I was using playtomic.com but with my perceived notion of their un-availability, i started looking at other options.. http://www.scoreoid.net/ seemed like a really good alternative till i realized that i needed a php capable hosting to be able to use it unlike playtomic which just works with js.

The hosting of playtomics' javascript library on their site seems to have some problem and i was unable to access it. I just assumed that i wouldn't be able to use this service since the browser would require a cross-domain ajax request to handle the data. Little did i know that xmlHttp and the corresponding m$ implementation already have this and that playtomic already uses it. So basically i can just get the playtomic js file from their git hub hosting bundle it along with the game and i should be able to show up a basic score board.

On another note.. i just discovered c9.io "cloud based editing software" pretty neat.. its' well integrated with the github... so it is extra easy to get started with your projects. .. do try it out if you haven't already..

Update: You can try the game online at https://sites.google.com/site/vkgamedev/home/colortheory

Download onClick

2012-02-22T14:36:00.003-08:00

Ajax requests to server are always expected to return text output and for some reason the

Content-disposition: attachment;

doesn't cause the browser to show the save dialog. I searched for a while and found a jquery plugin which does it but i kept looking anyway. One interesting solution was to include an iframe in the page and set its' location to the url which would download the file when that didn't work i just used the

var url = "cgi-bin/getreffile.py?" + $.params({qo:"LDS", sv:["dk", "df"]});
window.location = url

And surprisingly this worked well atleast on the browsers that i checked with.. (chrome, ff ).

2D Boy

2012-02-21T02:56:00.002-08:00

No this is not a blog post about the 2D boy game studio. ... its' about a 2D character i designed from scratch.. This was the first time i did it, the work i did with recreating the 2D characters from Sita sings' blues has certainly helped me a lot here. First i used MyPaint to create rough sketches of how i wanted the character to look.

Sketch of Characters

I wanted to go for a cartoon look but still wanted it to be a believable one. At first i tried to push for a simple Rayman style character but finally decided on this character. The game was going to use a side view.. so i had to work on creating a side view of the character.. I think the isometric view would have been better but the side view is what was requested.. :D

Side View of the Character

Once i got the side view done.. i wasn't too happy about the shoes so i tried to draw that separately so i can focus on its' details. Once i got the side view, i used Inkscape to create the colors and the texture. Once i got the texture done, I used blender to create a model with 2D planes, rigged it and its' all set to go now.. here is the result..

Rendered using Blender

The shadow of hair is pre baked (i.e it's in the texture), but the shadow cast by the legs and arms (i.e, self shadow) is all done by blender.. this is the right way of doing it because you don't have to worry about animations not showing the right shadows. I've uploaded the blend file on blendswap.com hopefully people can pick it up from there.
Update: the blend file is up on blend swap.com.. http://www.blendswap.com/blends/characters/2d-boy/

Update1: Just discovered a sprite sheet plugin for gimp.. http://registry.gimp.org/node/20943 works pretty well, i had to change the final image a little to match my requirement but.. it does the job..

Running Animation

Canvas Experiment

2012-01-31T16:06:00.000-08:00

I just discovered that you can put in your script and render stuff to the blog. Pretty cool hopefully i can put a whole game in it. I remember trying this before but it didn't work seems to be working now :D. It's pretty easy to get it just go to the html of the post and post your javascript and it works :) well not all of the things but for now this should do :)

DroidRun as Pokki

2012-01-30T08:28:00.000-08:00

Droid run is the first game i developed using the CAAT library. The code isn't exactly the most beautiful and well organized but i've managed to get it working but then getting it to work as a pokki was a whole other story. I was too lazy to do it but gathered just enough motivation to make it because i did start writing this game for the pokki 1UP contest.

In a rush to get to the finish line .. i moved the code around like crazy and made a lot of local variables as globals and just hacked away at the code without thinking much.. i just wanted to get it working.. may be next time ill' try to be a little more cautious.. :) I do plan to add in new features like ability to buy costumes and stuff but it can wait.

concept art

Any way if you are interested in getting the pokki for your computer.. click on the button below..

Download Droid Run for Pokki

DRUN

2012-01-22T14:27:00.000-08:00

The CAAT library is really cool for doing html5 games. I was impressed by the demo they had for the library. So i started to think of simple game ideas that i could quickly implement using this library and make it look good as well. Im' always in a rush to finish coding the games ive' started writing so they miss the fine touches of ui animations and stuff. I thought this could be a good library to start experimenting with to get some thing up and running really fast. Since this is the first time i'm using this library i haven't really used it the most effective way but I did have a lot of time to fine tune the gameplay and artwork. Im' yet to integrate the score board into the game but i'm pretty happy with the way it stands right now.


Click to Launch Droid Run

The basic idea in the game is to be able to jump to three different heights and the user has to choose wisely based on the obstacle course. The aim is to last as long as possible and collect as many squares as possible. I wanted to add different costumes and stuff which is pretty straight forward but for now it has only one droid suit. I hope to get this up and running for android device soon. Technically you should already be able to run this on any html5 compliant device but the performance may be a problem.

You can check out the game in action in the video below. You can also check out the homepage for the game at sites.google.com/site/vkgamedev.

JavaScript Frameworks

2012-01-11T13:18:00.000-08:00

I've always been against using frameworks for getting my javascript work done. I felt they were getting the way of performance and too much obscurity. But after writing my first javascript game, i thought it would be nice to use the jquery library. Which resulted in a better looking code but for some weird reason i couldn't get the setInterval() function to work with the animation effects from jquery. I did find some solutions online to fix the problem but i didn't bother to look too much into it as i was content with the UI without any animation effects. Then i came across this amazing demo. I was blown away by how beautiful everything looked. The fluid animations brought the whole game to life. It was just a delight to look at the animations. I decided to give this library a try. The documentation is pretty extensive and the samples provided pretty much cover everything you need to know. But the one thing they don't/can't tell you is how to use the library to fit your needs :) I spent a couple of days just trying to get a feel of how they expect people to write their applications im' sure i still didn't get it right, but i've got to a point where i have the gameplay ready and am working on fine tuning the experience. you know adding proper menus and stuff.

As you can tell its' a game based around the android logo. The funny part is that i got the gameplay idea from the android logo itself. :) Anyway.. since this is the first time im' using this library, im' not entirely sure if im' doing something wrong and hence screwing up the browser. Not sure if this is the best performance i can get from the Framework. That's usually the case with using the libraries. You can't really tell if you are using the library as intended.. i guess you keep getting good at it by using it regularly and trying to understand why a certain demo was written a certain way. But there is always this lingering doubt that probably the way im' using it is wrong. I really hope im' using it right :) hopefully it will be a good fun game to play.

Pokki

2011-11-02T16:06:00.000-07:00

Im' already a big fan of HTML5. I just love the power of canvas and the ability to be able to develop games for the web without the fuss of flash. This excitement reached the next level when i came across the pokki platform. The application just uses already available software packages like webkit, v8 javascript engine and are trying to do something like Chrome WebStore with offline apps only. The advantage though is better integration with the desktop environment. The fluid animation of the apps appearing and disappearing.. its' just beautiful. As soon as I discovered it i wanted to try making one of my html5 games available on it and thought "Closer" was the best option.. mostly because the other games weren't as good or fun to play. It was pretty easy to get the game running under pokki platform but making it polished enough for it to get published definitely wasn't. I have got the submission rejected twice so far.. nothing serious though and i think that helps in getting only the best applications on the platform. I just submitted the version with the requested changes.. and hopefully it will get through.. any way here is the app in action..

Ps: The encoding seems to have screwed up the colors a little but you get the idea.. pretty applications neat little framework...
Update: My Pokki has been approved and is available for download. Install pokki application and search through the new section. :D

CSS

2011-10-12T14:03:00.000-07:00

This months theme for experimental gameplay was slicing. I was thinking about a fast paced game but i found a game which was doing exactly what i wanted to do and was pretty damn fun to play too.. you might find it fun to play http://www.gamesbutler.com/game/3140/Glow_Cut/.

So with that gameplay off the table i wanted to try something funny and ended up with this game called CSS (Combat Simulator for Skeletons) you slice through the skeleton to make parts of it fly and re assemble. You can click on it as well. The gameplay is pretty simple and i almost feel like i failed to make something good but im' posting it any way because that's what experiments are for. You try and fail.. that's the whole point of an experiment. You can check out the game at http://balaji.me/vkrishna/css/.

Some More Art

2011-10-06T14:14:00.000-07:00

Here is some more artwork i did for the project. I think i should stop focusing on the art and try to get some actual game done now :) I still have to write export script for using blender as level editor. Once that is done i should be able to put together some good level to play with. I still have no clue what the story is going to be, im' inclined to take it to humorous side, but ill' have to think about it.


BlenderSetup for Skeleton


SkeletonCharacter


Props for Game

Ps: If you do use the props texture please attribute it to me.

WitchDoctor

2011-10-03T14:45:00.000-07:00

Ive' been working on a simple action game. I haven't been able to decide on the story or the level design. But i think i have got the basic gameplay working pretty well. I was also thinking about some mini boss character and witch doctor seemed like the perfect fit for what i wanted to do .. so here it is...

The Witch Doctor


colored character from prev post

I still need to get these characters rigged up in blender, but right now im' having fun with the character ive' managed to rig in blender. Here is the video showcasing the combat. I hope ill' be able to finish this soon :)

OfficeOnWeb

2011-09-28T05:42:00.000-07:00

A couple of weeks ago i was working on a presentation and needed to work on it at home as well. I didn't like the fact that i would have multiple copies of the same presentation lying around as i keep working on it. So i thought the best idea would be to use the Google Docs. The first problem i ran into was that there was no way i could add equations to a presentation. I know lot of papers require equations and it makes sense that the you have access to this tool when you create a document in google docs. But if you wanted to present that work at say a meeting there is no way to actually include that equation in the presentation. With all the push that Google is giving for the web as one stop place for everything, I must say i was surprised that these basic things were missing in the Google Docs for presentations.

I did manage to find a work around for this thanks to the discussion forums but even that quickly proved to be a waste once i needed to deal with equations which had matrices and then i found the most wonderful tool to create equations online
http://www.codecogs.com/latex/eqneditor.php
You should check it out if you intend to use it for creating presentation on Google Docs till they come up with something decent.

Presentation @ Astron

Invasion

2011-09-21T18:57:00.000-07:00

This month's experimental gameplay theme was story. Telling a story in a game is kind of hard.. atleast for me, i've never done it before and was confused about what to do. Because almost all of the games that are out there use in game movies or audio or loads of text to get the story out there. Text obviously is the easiest way to do it. But I didn't want the user to have to read loads of text scrolling through the screen, I wanted to minimize the text as much as possible.. I did end up using text but i think I have managed to hit the sweet spot. The story is short and the way you play effects the story. Thanks to the JQuery and loads of plugins it has.. ive' been able to create what i think is a good story based game.. the story is kinda of lame though.. I couldn't manage to come up with a compelling story :( guess its' time i start reading some books :D. So here goes.. check out the not so awesome story in the html5 goodness.. @ http://balaji.me/vkrishna/invasion/. Hope you guys like it.. im' not too proud of the way the game looks.. but i like that ive' managed to make a good gameplay driven story :)

Obsession With Menus

2011-08-28T13:43:00.000-07:00

Iv'e always been obsessed with putting in animations for the menus. We did put something together for Adrian, a game I worked on along with some friends at college. But the animations were pretty much predefined you could either slide them in blink them that kinda of stuff. It was pretty good, but in the recent times especially after watching so many iphone apps which have such smooth transitions etc between screens, And the wonderful ui you can create with html because of the javascript speedups Iv'e started thinking its' probably time to get this done right or at least to my satisfaction :D.

The weird idea i got was to create keyframe animations for the UI and then use it as the menu. This is pretty much the standard way of doing things in blender game engine. You just move the camera around in a scene or make the ui elements slide in out of the view. I wasn't sure if i could pull it off in my own game. So I kept putting it off to try later. Then i came across a video explaining how the UI designers used blender for Gnome3 as a prototyping. I fell in love with the Gnome3 ui right from the beginning and once i saw this, i was determined to try it out.. And so i started implementing a basic game engine in python which would be able to use the key frame animations and would be useful as menu as well.

Here are some boss demon concepts i made for the game.. have to decide on colors etc

More Enemies

And ive' finally managed to create the model for main character, there is a lot of polygons spent on the head of the character, hope i can get the animation right, still have to rig the character though.