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Draggable objects

redblobgames.com

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Re: Draggable objects

#11

Post by npinsker »

Off-topic a bit, but I've been curious about a 2D pathfinding problem for a while that this site doesn't seem to tackle despite having lots of articles on the subject. Is there an algorithm out there for finding "enclaves" (i.e. places where you might want to place rewards, spawn the player) within a large 2D terrain grid?

Not super precise, but given a 2D boolean array of pathable/unpathable cells, say generated by Perlin noise, find locations that are only accessible via a relatively narrow "choke point". Example: https://imgur.com/a/jFPXlS5

Standard pathfinding algorithms don't provide enough information to do this, but maybe there's some kind of heuristic approach that could work well.

Re: Draggable objects

#12

Post by notsurenymore »

kibwen wrote: post #9
michaelwm wrote: post #6

Amit was an instrumental part in the development of one of my favorite video games, Realm of the Mad God. It was a masterpiece of the Flash game genre, and its guild feature introduced me to many lifelong friends.

RotMG has a great idea that I wish more games would copy: difficulty scales with elevation. If you want to take it easy, stick to the coasts. If you want a challenge, strike inland towards the mountains (or follow a river upstream). It's a great way of intuitively expressing difficulty ranges across a sprawling world map, and I remember being disappointed the first time that I played Skyrim that it didn't seem to do…

Doesn’t Ark kinda do this, except with elevation, it becomes more difficult the more inland you travel.

Re: Draggable objects

#14

Post by stefan_ »

npinsker wrote: post #11

Off-topic a bit, but I've been curious about a 2D pathfinding problem for a while that this site doesn't seem to tackle despite having lots of articles on the subject. Is there an algorithm out there for finding "enclaves" (i.e. places where you might want to place rewards, spawn the player) within a large 2D terrain grid? Not super precise, but given a 2D boolean array of pathable/unpathable cells, say generated by…

Lots of pathfinding solutions prefer to work with connected convex polygons (since inside the polygon, you can always go straight to every other point inside). You could merge your cells into these polygons and then filter for small ones by area, I guess.

Re: Draggable objects

#17

Post by adanto6840 »

Likewise, Amit is phenomenal and the content (and especially its presentation) is really second to none. The value he places on ensuring links stay working, and that content is accurate and updated — is truly phenomenal and almost inconceivable these days.

I’ve also always enjoyed every (virtual) interaction I’ve had with him, however brief — and appreciate that he remembers me and the problems/challenges we faced in my games.

SimAirport and SimCasino very likely wouldn’t be the same (or would have taken much longer to achieve, at best) without his content.

Just a class act; one of these days I’d love to buy Amit a beer or a coffee. My invite doesn’t expire, perhaps next time you’re in the area! :)

Re: Draggable objects

#18

Post by sarnowski »

Playing around with a hex based game myself, the bookmark to the Hexagonal Grid is a constant companion over the years. It was updated slightly over the years with some visual cues. Amazing presentation, and so great to learn.

Re: Draggable objects

#19

Post by Marazan »

npinsker wrote: post #11

Off-topic a bit, but I've been curious about a 2D pathfinding problem for a while that this site doesn't seem to tackle despite having lots of articles on the subject. Is there an algorithm out there for finding "enclaves" (i.e. places where you might want to place rewards, spawn the player) within a large 2D terrain grid? Not super precise, but given a 2D boolean array of pathable/unpathable cells, say generated by…

Brute force and ignorance approach:

Choose random starting point and compute distance to all other points on the map. Repeat for multiple random starting points.

Average the distance.

Points with high average distance are difficult to reach.

Re: Draggable objects

#20

Post by feoren »

Apart from the excellent subject matter, I often pull up this site during UI/UX discussions. Amit clearly has the ability to do really advanced JavaScript visualizations, but he only uses it exactly when necessary. Most of it is a plain document like you might write in Markdown, but when he uses JavaScript, it's illuminating, connected to all the other examples, and clean. Any animation he uses is clearly initiated by the user, and is there not because it looks cool, but because the intermediate frames help the user understand what's happening. It also never moves the rest of the layout around. I go back to this site any time I'm pondering how to do good online documentation, interactive help, tutorials, or even text-heavy presentation of results.
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