Evolution of robot sentry turrets

I finally took an honest crack at the robot sentry mini-boss today, and got it mostly done. The art is terrible, but I’m hopeful a donor will fix that. I thought it might be interesting to detail how the enemy evolved throughout the day.

I started just by getting all their parts drawn on the screen in roughly the correct place, as well as a physics model for their body:

Not bad for a first attempt

Not bad for a first attempt

Next I added some basic player-tracking, so that each turret is always aimed exactly at the player (as much as possible):

Instantaneous tracking looks neat, but it’s not super fun to play, since humans are no match for machine reflexes. To make it a fairer fight, I had to add in a maximum turning speed for each turret:

I got it mostly working right away, but then spent way longer than I would have liked working out the kinks. Here it is fully working in another test area:

The guns aren’t quite done: they need to actually shoot, of course, and to cause damage when you touch them and their projectiles. They’ll also be impervious to attack at times, then open a hatch and expose their giant glowing weak point. People seem to like it when video game enemies do that. Hopefully most of the brain-heating trigonometry is out of the way, though. I had to lay on my carpet, moaning softly, at one point.

6 thoughts on “Evolution of robot sentry turrets

  1. Good work. The last video where the turrets lie down against the terrain they’re anchored to while still trying to sight the player is awesome. Even without being able to shoot bullets, a camera variation could just report your presence, perhaps dispatching new enemies to cleanse the area. Players could shoot them to disable the reporting and reduce the number of enemies sent, but they’d have to shoot them before they turned to see them for maximum effect.

  2. Yeah, I’m not sure how I feel about enemy spawners yet, although I think it’s pretty likely they’ll find their way in there eventually πŸ™‚

  3. Robotic rats, intelligence-gathering for the network? Maybe small (2″) bugs could crawl underfoot and only attack the player 5% of the time on contact (squeek!). Proximity to moisture (water tiles, the player and animal enemies) could increase plant growth on nearby collision tiles. Standing under falling water could eventually infect the player with parasites or disease.

    The main turret could fire two kinds of rounds at different rates. The normal shot would dictate the player’s movement and a less frequent but heavier shot would destroy a collision tile if it hit it. Use existing systems to create new gameplay situations and improve interoperability between procedures. So far EfE is looking insanely awesome.

    • Wow, these are great ideas! I’m gonna have to steal some of them πŸ™‚ I will definitely have multiple iterations of some enemies, each having having slightly more strength and different capabilities. Having enemy fire destroy tiles could create some pretty interesting scenarios.

      • Thanks. I’m half-bent when I think of these things most of the time.

        I also updated the surface_3.png file as I made a mistake earlier and it wasn’t the image I wanted. I need to go ahead and fill in the missing interconnective tiles, as what I have doesn’t cut it without some serious fiddling. Here’s a demo screenshot using all three sets:


        I’d just consider them placeholders for now.

        Did you ever listen to the song I put up? No prob if it doesn’t fit in with the game. I wrote a lot of music and that is one of the few that I thought might be appropriate.

        • I did listen to it! I think I responded on one of these posts, somewhere. I think it’s great and I’ll probably end up using it in the game!

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