RT @LunarRayGames: More future versions of enemies on today's Timespinner devstream! Pixel art and design! 1-4pm PDT every Tuesday at https… (Today)

@SaltyPepperG t.co/1dpxpaE6E5 (Today)

@MagpieMcGraw I see. Do you have a programming day job or do you only code as a hobby or whatevs? (Today)

@SaltyPepperG yeah I've gotten better at this over the years, but when my final tasks involve "talk to other humans" I shut down hahah (Today)

@TyrusPeace hmmm right yeah that makes sense. I wonder if I tied my chill out things to my projects more if it would help (drawing, etc) (Today)

Also I feel like I'm at the very end of Sky Sisters dev and the rest of it involves doing things I don't like so I'm procrastinating forever (Today)

@MagpieMcGraw right I have heard that actual coding time can be like only 2 to 4 hours a day for most people :o (Today)

@bmau_ro yeah I probably have weird data on this stuff. a lot of folks I talked to about time tracking track SO MUCH TIME compared to me x_x (Today)

@UndeadBarryGibb @SnugglePilot labor 2.0 (Today)

@Teknopants yeah totally but things don't get done waiting around for inspiration ya know? Why is making stuff so gosh dang difficult (Today)

@SnugglePilot dunno seems society likes that number a lot (Today)

@DrMelon It always seems like the mega successful artists and creators out there have super human focus powers~ (Today)

I want to be someone that can just work on the same thing all the time 8 hours a day every day but it just never works out for me. (Today)

Working on Sky Sisters this month has been incredibly draining so I'll do the irresponsible thing and goof around with a side project~ (Today)

@psysal hahah yeah sounds about right. I like how the anime advanced they started to adapt more of the actual game's rules. (Yesterday)

@psysal YEAH I loved the anime and my friends and I got into "AS A JOKE" and it turned out to be really fun so we went crazy with it (Yesterday)

@psysal uhh YEAH I played super competitively for a number of years and a friend from my locals won nationals in 2009!!1 (Yesterday)

@psysal i hope you brought your exodia with you (Yesterday)

@gritfish nope sorry been a long while since I've used it :[ (Yesterday)

@Managore @MattThorson right just rotate your sprite 90 degrees and you're good (2 days ago)


2014 - 4 - 9 / 4:11 am / general

Dev Log: Pathfinding Fun


Like a cat chasing a laser pointer, I have some basic enemies chasing paths through the skies.

Right now I'm using A* and although I don't really know what is going on that much, I have a system that enemies can use to find paths to their destinations. Normally I wouldn't bother with any sort of path finding, but for this game I want enemies to have to intelligently navigate through obstacles that the player is deploying, so my usual "make up a path finding function that doesn't actually path find but sometimes works out" function wont cut it.

What I have currently is a pretty straight forward set up:
- One PathFinder instance in my Scene. It extends Entity so that it can be updated by the scene automatically.
- Enemies request a path from PathFinder and also register a callback Action with the request.
- The PathFinder instance adds the request to the queue.
- Every update the PathFinder will take the top item of the queue and start the path finding process.
- The actual A* algorithm and calculations are run on a BackgroundThread so that the game can continue while this is going on.
- When the path is done calculating the callback is fired, and the enemy now knows about its path.
- It chases down the nodes that were added to its path.

I made a quick change to the A* algorithm as well under the sage advice of Chevy Ray: I'm using a maximum movement value that will stop the algorithm if the move costs become too high. The result is that the algorithm will return a partial path to the final target instead of the entire path (which could take a long time to calculate in a set of nodes with a lot of open spaces.) So with this in mind the rest of my logic looks like this:

- When the enemy reaches the last node, it checks to see if its close to its intended target.
- If not it requests a new path to its target.
- If it is then it will enter its attack behavior, whatever that is.

So far this seems to be working out pretty well. I have a lot of work to do with how enemies will end up treating their path nodes in regards to their actual movement. Right now they just try to move toward each node, but with a lot of nodes together they end up having some trouble, like that wiggling in the animation above. Something like an averaged out path between a lot of nodes might work better... hmm!


2014 - 4 - 11 1:08 PM


This is confusing hahaha


2014 - 4 - 11 2:05 PM


You're telling me ;D


2014 - 4 - 12 2:23 AM


Looking sweet! :-) Hmm, if the nodes are this close together, maybe some kind of weighted velocity vector made of the next x nodes, weighted by their current distance to the fishie could smooth out the animation a bit*scratches head*

Can't wait to see what kind of game this is going to be! :D


2014 - 4 - 15 9:23 AM


Often times actor's turn towards their desired heading before moving via a rotation lerp or a custom animation based on the size of the angle. Having the pathfinder return a starting direction vector as soon as possible even if the path is not nearly complete will allow the actor to look smarter by starting to turn towards the desired heading while pathfinding is still in progress. This helps hide the pathfinding latency and makes your actor more responsive.


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Hi! My name's Kyle, and I make video games most of the time in Denver, Colorado. Here you will find my thoughts, games, websites, doodles, and other stuff like that. I worked on Snapshot, Offspring Fling, and a whole bunch of other games. I also created and maintain Otter, a 2d game making framework. If you want to get a hold of me use the form on the bottom of the page, leave a comment, or just tweet at me. I try to post three times a week. Thanks for stoppin' by! You're the coolest.

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