Archive for March, 2009


Gameplay and Mathematics

March 22, 2009

Well I have a very good idea of gamelay.  I want to merge the “defending your humans” in their houses, with the prevention of virus spreading through the landscape.  Evidently these 2 ideas come from Zarch and Defender.  I think Defender married the whole level based schmup thing with objectives and the differing types of attackers, really well.  What I want to do is have an infected landscape (say above a basic percentage) then explode, as per Defender, with all the aliens turning nasty and going after you, rather than your houses.  Evidently this would still occur if the aliens got your humans from their houses too.

I like to think the Lighthouse looks so cool on my small planet, that I will feature it specially somehow.  Don’t know how yet.

Oh, another cool thing, when a “lander” for want of a better name at the moment, takes a human from a house/windmill, and reaches an arbitrary orbit level, it will “mutate” as per defender, but also shoot a laser bolt down to the house below, desroying it, “independence day” stylee 🙂

Now the maths for this is all getting pretty hairy, but I will make a future blog about the use of Quaternions in all this.   Heavy going, trust me…..

To give you some kind of idea of how far behind, the blog of the game is, behind actual development, I was writing a particle object last night for the explosions 🙂  Everything is coming along very very nicely !  Have I mentioned how much I love Objective-C yet ?   very sweet.  Damn shame I will have to re-write all this game to be able to port it …


Algorithms for GeoSphere generation and random planet surface

March 12, 2009

OK, so there are a number of ways of generating a geosphere, but I found this article very useful indeed.

Basically start with a simple shape like an octohedron, and start subdividing the surfaces.  Before you know it, one GeoSphere – great !

Now there are millions of pages about random planet surface generation.  Generating something unique though took some digging.  This algorithm was perfect for my needs

sweet 🙂


Planet surface features

March 12, 2009

OK, so I needed some items to go on the surface of my small planet.  It’s off to the 3d modelling package we go ….  Everything needs to be pretty low poly, as its anticipated that the game will whizz along at a pretty swift rate, and I don’t need things to be particularly detailed.

Here is what I came up with for the moment


When shown on the iPhone, the windmill blades all spin around, and the light coming from the Lighthouse is nicely see through, and spins around, and the wind turbines are nicely painted red and white, and also zoom around 🙂  All looks very funky actually !


Generating a small planet …

March 7, 2009

So the first step in this game is that the whole thing will take place around a small planet.  Now I don’t want textures.  There are going to be loads of polygons flying around as it is, and I don’t want to push the iPhone too much.  Plus going for Zarch styling means that I get a cool looking effect without texture mapping.

However, a small planet in graphical terms can be drawn in two ways, using a latitude and longitude approach, or what is called a geosphere.  Now a geosphere is much more interesting to me, as the lat long approach means you get tiny triangles at the poles, and large ones at the equator.  The geosphere is something that can be colored using triangles of equal size over its surface.  Perfect for zarch style graphics.  Heres a pic to show the difference.