Thanks for seeing what you can do.

regards


p.s.: i know that feeling

well I think that are too much nodes:

the engine freezes at the position on the picture

here you can download the level: CLICK HERE

Hi Samb!

Ouch!!! Well, thanks for running that test! I'll download the level and test it over the weekend. I owe you one!!

- Bret

Good job Bret,

I wish I had more time to play around with it. I did find one minor problem. If the moving entity can't see the first node the program crashes. This could be a problem if someone has wondering monsters that might somehow not be able to see the first node in some circumstance or a moveable object blocks the entity's view to the first node. The program really should just not move the entity and return a 0 or something for move not being possible in that case instead of the program crashing. I suppose this could be tested for in C-Script, but it would be better if the dll handled it I think, or maybe not, but your sample program should show how not to have this happen, because it will eventually happen somewhere when people use the dll.

I do like how simple you made it to use. Very nice.

Loco

Locoweed - Ah yes! You're correct! I fixed the issue and it'll be included in the next update.

Samb - You tripped upon a pretty crafty issue. It will definitely take me a few days to solve your issue. Here's what I think is happening. Each node can have a maxium of 4 neighbors. During the initialization stage, the nodes try to link to their neighbors. In fact, they try to link to ALL of their neighbors. The problem is that nodes don't necessarily know who their neighbors are. They just accept the first ones they can find, which may not be necessarily the closest ones. Once all 4 neighbor slots are full, the rest are ignored.

I need to improve the initialization routine so that it prefers closer neighbors over ones that are farther away. That change will have to wait for the weekend.

Thanks for the bug reports!! I'll get 'em all cleaned up as soon as possible!
- Bret

well I hope you can fix it
then I make a little pacman clon
but very good work
the easiest pathfinding I'd ever seen here

Samb,

This problem turns out to be VERY difficult to solve. I woke up numerous times last night thinking about a solution, and most of them weren't adequate.



The question is, how do you know which neighbors you should connect to? "All of them" isn't always a good idea. Check out this example:



The green lines represent neighbors connected to our source node. The red lines represent a possible path that could be choosen to reach the goal. I might be able to fix this by following closer neighbor nodes first. Yeah... maybe that's the ticket. It would require sorting the neighbor nodes by distance, which might slow down the initialization a bit...

I'll keep thinking on it.

- Bret

Ah...

Sorry for thinking out loud, but I wanted to correct a flaw I made. In the last example that I had posted with the red path.... that path would not have been choosen as the final path. The correct path still would have been used.

I won't go into details, but sorting the neighbor nodes by distance still seems like a great solution. I'll code it once I have a chance. I could leave them unsorted, but sorting them during the initialization stage will potentially save time during the actual pathfinding.

Cheers!
- Bret

Ok!! I think that I ironed out some of those bugs. Download the new version at the same url:
http://www.gamebeep.com/freebies/ez_path_src.zip

There are a few changes, but the most important ones are:

1) The function pf_to_ent() doesn't crash if there's no start node in sight. Instead, it returns "1" if everything is ok and "0" otherwise. It'll return 0 if there's no available start node.

2) After some intense programming, I fixed the "neighbor" problem that was causing some issues. It's ready for round #2 of testing!!


I also added these .dll functions:

DLLFUNC long pf_set_node_collision_distance(var dist)
An entity will reach a node when they get a certain distance to it. This method can set that distance, which defaults to 20 quants.

DLLFUNC long pf_set_max_path(var dist)
Defines the maximum path search distance.

DLLFUNC long pf_set_ent_collision_distance(var dist)
Defines the distance that an entity has to be within its target to trigger the my._PF_REACHED_TARGET flag. Defaults to 10 quants.

I'll write more about these functions later once I update the documentation.

Have fun!!
- Bret

Oh, one other thing. Samb, your pacman level should work with the new .dll. It works for me now!!