I have been working on various gameplay bits.. searching, recoil & recovery, action states. Also the zombies now attack, and eat you when you die (heh).
Next up, I’m working on the inventory system and on controlling multiple characters. The idea is that you’ll have to co-ordinate several characters at once; some searching while others defending, etc.
As you probably know, it’s important to use Texture Atlases for efficiency reasons on mobile devices. The idea is that you pack lots of textures into one big one, and then use UV offsets to define which region of this large texture to display in your HUD components. This means that only one texture has to be referenced by the graphics hardware. But it can be a bit fiddly calculating the UVs, especially if you want to add new textures to it later.
I have put together a nice workflow for this, so I thought it might be useful for other people too..
Step 1: Create your texture atlas. I use a program called Texture Packer for this, which combines your textures into a single PNG and also exports an XML description of it (which we’ll need later; we could of course manually write the XML but it’s a bit more work that way..)
Step 2: Write or export your XML. My Shiva code a bit later will assume the following format, which is what Texture Packer gives us. It simply encodes the names of the images (sprites), along with their positions and sizes in the atlas.
<TextureAtlas imagePath="ZS_icons.png" width="512" height="512">
<sprite n="backpack" x="204" y="2" w="160" h="186"/>
<sprite n="rotate_left" x="366" y="51" w="48" h="47"/>
<sprite n="rotate_right" x="416" y="2" w="48" h="47"/>
<sprite n="search" x="366" y="2" w="48" h="47"/>
<sprite n="shotgun" x="2" y="2" w="200" h="86"/>
</TextureAtlas>
Step 3: Import the xml file and texture atlas in to Shiva
Step 4: Create your HUD. Anywhere you want a texture out of the atlas, just set that HUD component to the Atlas texture (it looks a bit weird at design-time..)
Step 5: Add an XML variable to an AI, and set it initialised from the imported xml. (I call my xml variable xmlZS_icons, and hard-code that in the code below)
Step 6: Add the following function to your AI:
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function MyAI.SetUvsFromTextureAtlas ( sComp,sIcon )
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local r = xml.getRootElement ( this.xmlZS_icons ( ) )
local imgWid = string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( r, "width" ) ) )
local imgHgt = string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( r, "height" ) ) )
local c = xml.getElementChildCount ( r )
for i=0, c-1 do
local e = xml.getElementChildAt ( r,i )
if ( sIcon==xml.getAttributeValue ( xml.getElementAttributeWithName ( e, "n" ) ) ) then
local uscale = string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( e, "w" ) ) ) / imgWid
local vscale = string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( e, "h" ) ) ) / imgHgt
local u = string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( e, "x" ) ) ) / imgWid
local v = 1-( string.toNumber ( xml.getAttributeValue ( xml.getElementAttributeWithName ( e, "y" ) ) ) / imgHgt )-vscale
local comp = hud.getComponent ( application.getCurrentUser ( ),sComp )
hud.setComponentBackgroundImageUVOffset ( comp, u, v )
hud.setComponentBackgroundImageUVScale ( comp, uscale, vscale )
return
end
end
log.message ( "Unable to find icon '"..sIcon.."' in texture atlas!" )
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end
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Step 7: And finally, whenever you instantiate your HUD, call the following for each HUD component that’s included in the texture atlas:
this.SetUvsFromTextureAtlas ( "MyHUD.MyComponent", "sprite_name" )
I still haven’t decided on the name for this game, so “Dead County” is a working title. I have been working on the zombie A.I. (it’s very easy to make them look dumb, heh) and throwing in some physics-controlled objects to add to the fun. It’s a pity my gun doesn’t work yet..
Edit, Aug 16th: now the shotgun works.. 
I have been having fun scratching around with some ideas for a 3rd person zombie survival game, in which you’ll progress through a series of randomly generated towns, and you’ll have to find resources and items, meet new characters and level up their skills, and all the while the zombie threat grows harder and harder. Maybe the game ends when all playable characters are dead.
So yeah, first step is algorithmic town generation. I have bought some nice road models from turbosquid and a bunch of buildings from dexsoft, plus a lot of stuff I had already from Darkwind (including tombstones, buildings, trees) and here’s a first cut at a random graveyard.. the home of the zombie spawnpoints.
A bit more work and we have the basis of a town generation system. The roads are put in first, followed by the graveyard and buildings. The orange areas show ‘free’ regions; the idea is that we search for random free space for each object, starting with the biggest and finishing with the smallest.
