Ludum Dare 32 — April 17th-20th, 2015 — Theme: An Unconventional Weapon

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Magnetic Fields

by oparisy - Compo Entry

You can emit a magnetic field.

Use this unconventional weapon to defeat your enemy!

Edit: uploaded a fixed version with proper screen size detection and VSync.

Edit: added link to source code.

Edit: uploaded a fix to avoid halting on OS X if ARBDebugOutput is not available.

Downloads and Links




Apr 21, 2015 @ 9:04pm

Audio was a bit annoying. Graphics looked nice. Gameplay didn't seem to offer any variety throughout though.

Paulozz says ...
Apr 21, 2015 @ 9:33pm

Intersting concept, I would like to have more levels.

NMcCoy says ...
Apr 21, 2015 @ 9:38pm

Nice take on the theme - I like seeing games that incorporate unusual mechanics in order to fit the theme, and this does a good job of that.

Dynad says ...
Apr 21, 2015 @ 9:46pm

Funny weapon using gravity, after kill the enemy once.. I thought you would get more enemies or a larger world with obstacles and such.. but yeah, its only 48 hours ;)

Apr 21, 2015 @ 9:49pm

The concept is good, but if I had more variety in gameplay, different reactions of the enemy, would be better.

Docjekyll says ...
Apr 21, 2015 @ 9:50pm

I got this error: "Could not find the main class: Capsule. Program will exit."

I'm running Windows 7 SP1

Smiley says ...
Apr 22, 2015 @ 9:17pm

java.lang.IllegalStateException: Function is not supported
at org.lwjgl.BufferChecks.checkFunctionAddress(
at org.lwjgl.opengl.ARBDebugOutput.glDebugMessageCallbackARB(

on OS X 10.10 :(

f7f5 says ...
Apr 22, 2015 @ 9:43pm

I like the idea, and it's kind of fun at the beginning, but it gets repetitive quickly once you find how to hit the AI.
Some more level with tougher enemies would have been great.

SpeirCeol says ...
Apr 23, 2015 @ 3:22pm

Interesting concept, would like to see more, the noises were quite annoying tho. anyhow, thats a nice entry, good job!

Awpteamoose says ...
Apr 23, 2015 @ 9:20pm

Mangetic mechanics are always interesting. But, need more variable enemies and levels.

oparisy says ...
Apr 23, 2015 @ 9:30pm

@Docjekyll: I'd like to understand why the game does not start on your computer. What version of java do you have installed? Could you type "java -version" in the command line and give me the result? I'm afraid this will not work under Java 1.7.

Also, do you only have this error message, or can you provide me with a full stack trace?

oparisy says ...
Apr 24, 2015 @ 6:52am

@Smiley Thanks for you feedback! I coded this from scratch (no engine) so I am very interested in fixing issues on various platforms.

I uploaded a new version which should not halt with this error message on your system.

Apr 25, 2015 @ 8:43am

The sound effects could have been a bit more subtle. They were a little bit too... blunt I suppose? Some background ambiance would have also helped balance things a bit. With the visual style I'd imagine something sort of soothing. And the sound effects being very subtle.

The effects felt a little less like magnetic attraction and more like standard velocity and speed. It sort of just tries to move towards you as fast as it can, no matter how close or far away you are. Of course it doesn't have very good "brakes" haha, so it normally overshoots your positions. I'd imagine this is what's going on behind the scenes, which is why it feels like it does. It would have been interesting if it were more like a magnet, and you have to move towards it to pull, but there's the danger of it getting too close and... well, you know, you've probably played with magnets before.

Semantics aside, the gameplay is straightforward and generally works well. I was slightly confused at first as to what was going on but I picked up soon enough how the game worked and what I needed to avoid and lure around. Played one round successfully and felt like I had enough.

It gets a bit tedious attracting the thing around into the wrenches. You pick up pretty quickly how easily the thing overshoots you and it's pretty simple to get it to go where you want it to go. So the challenge and learning how to lure it around was a bit bland.

Art wise the game is kind of pleasing all considering. The colors chosen were nice, though I don't think the wrenches fit with the rest of the game's geometry. They felt pretty out of place to be honest and I think substituting them for something more abstract and basic would have gone along with the other pieces well.

oparisy says ...
Apr 25, 2015 @ 12:49pm

@CriticalMammal Thanks for your detailed review. This is my first LD compo and I spent 80% of my time coding the underlying rendering code and interfacing it with physics. This definitely lacked playtesting and adjusments.

I designed most of the game with basic placeholders (cubes and tores) and quickly did some modeling at the end to replace them; hence perhaps the mismatch your perceived.

The movements of the enemy are force-based but this is not supposed to model a gravity field; the player/wrenches interaction does, though.

Langouste says ...
Apr 29, 2015 @ 4:49pm

Super Game! I love it ;) Thanks

jhell says ...
May 4, 2015 @ 8:41am

Managed to kill the enemy despite the lack of azerty support :D. Really cool idea, I would've liked an effect when my field is active, but other than that, pretty fun.

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