27 January 2013
Comments: 1

Impulse – an updated Thrust

Impulse is my interpretation of Thrust, a gravity game from the early 1980′s.

I started the project, over a year ago, as a Shiva3D learning exercise, inspired by a clone of Thrust I’d found on Android Market. The biggest complaint from users of the clone was that the touch screen version had controls which made it unplayable. I decided to fix it.

At about 70% of the way through the project, I’d learned what I could and decided to shelve it.  The game was largely playable, but it had no UI, needed more graphics and also required some serious polishing. All of this is very time consuming and I couldn’t see any commercial viability at the time.

Recently, I’ve decided to move forward with my plan to release a number of smaller, good quality game projects, using the “shotgun” approach to get  noticed and hopefully help support Solar and Exoplanet Explorer. Finding time to implement the plan was the main issue, which sort of resolved itself when Blackberry announced their final Portathon. That gave me enough incentive to dust off a few of my old projects and quickly finish them off. Impulse was one of these.


I’ve decided to implement the first 12 levels of the game, which featured six distinct level designs played in two different modes. I never managed to complete the game, because I found the third and fourth modes, which featured invisible walls, impossible. The game was renowned for it’s difficulty level, but I’d rather make the game a bit more accessible. People who enjoy cutting their lawn with a pair of nail clippers can always fire up an emulator and play the original.

The levels mimic the layout of the original game as does the ship design. Everything else is up for grabs though, and I’ve made some significant changes to the controls because a touch screen doesn’t really lend itself to button/keyboard layout that the original used.

The problem with touchscreens is that there’s no tactile feedback, so if you have too many buttons to press, it’s easy to end up losing your place. With this in mind, I’ve decided to get rid of the shield button, and just make it automatic. This change also requires the limpets (enemy turrets) to shoot more often and be more accurate to make up for the distraction they used to cause. Each hit causes the shield to briefly flash, followed by a significant decline in fuel reserves. Unlike the original, running out of fuel isn’t game over, but it does lose you a life.

Although I wanted to keep it to two buttons, there is a third that’s used to activate the tractor beam, which is semi-automatic. When you get close to something that can be grappled, the tractor beam button lights up. Tapping it will activate the beam, which will remain engaged until you’ve either filled your ship’s fuel tanks, or latched on to the pod.

Oh, and the plot is different too. I can’t really recall the original story, so I’ve decided not to refresh my memory and just make up my own.


A shot of the first level from the original Thrust


A shot of the same first level from Impulse

Blackberry update

Well, RIM seem to be getting through their app submissions from the last Portathon. So far, I’ve had all of mine rejected due to technical issues on the BB10 platform, and additionally, Impulse because the enemies don’t shoot in the version I submitted.


OK, I had a feeling Impulse would be rejected because I’d had to work flat-out for 36 hours getting my five apps ready for submission. There were bugs in it, but I’ve spent the past few days fixing everything. It should be ready to re-submit in the next day or two.

  • http://www.facebook.com/jpentecost15 Jesse Pentecost

    Yes i hope i we get your apps for launch!