A* pathing algorithm for detecting blocks in a tower defense game?

[SH4D0WS1N]

[Resolved]A* pathing algorithm for detecting blocks in a tower defense game?

Could someone please make the A* pathing algorithm (or a better one if you know one that will work) with a condition I can use to check if a path from point A to point B is there == true?

Note:
A* uses eight directions, but for what I need it only needs it use four direction (up, down, left, and right)

 

[emootootoo]

Comparison((PointPathingIsConnected((UnitGetPosition((EventUnit()))), (UnitGetPosition((EventUnit()))))), ==, true)

that maybe?

though i guess you might have to put ground pathing down your lanes for it to work and id assume towers would override it with no pathing

 

[SH4D0WS1N]

It doesn't appear to take into account buildings or the drawable pathing (red color), as I can't get this to return false.

EDIT2: It takes into account doodads, now with my extreme lack of knowledge of the data editor, I get to try how to replicate the pathing of a doodad.

EDIT3: The above was unsuccessful, however, I have come up with an inefficient work around, basically I'm going to make all of my towers have no pathing, them I'm going to create a (most likely) invisible doodad underneath them that will prevent pathing.

EDIT4: Doodads created by triggers appear to have no pathing, testing completely right now...

 

[Arkless]

You can find what you search for in the advanced ai functions, it returns the distance for some specific unit to a specific point (returns an integer, -1 if there is no way). It is a gui function btw..

edit: the name is "AI Pathing Cost Unit"

 

[SH4D0WS1N]

You can find what you search for in the advanced ai functions, it returns the distance for some specific unit to a specific point (returns an integer, -1 if there is no way). It is a gui function btw..

edit: the name is "AI Pathing Cost Unit"

You sir, are a god.

 

[Arkless]

You sir, are a god.

I found that function after completing a pathing algorythm i needed during beta time... :banghead:

 

[SH4D0WS1N]

I found that function after completing a pathing algorythm i needed during beta time... :banghead:

At least you were able to complete yours

 

[themean]

maybe you can found what you need here
http://forums.sc2mapster.com/development/project-workplace/5516-wip-line-tower-wars/

 

[Frozenwind]

Hm, that guy found a smart alternative. Checking the towerline instead of the creepline. Doesn't really work for a maze around a checkpoint though. Yet you are able to detect a circle in there. Though, if the towerline splits up, it'll slowly become harder.
Oh well, add all checked towers to an unit group and if it circles, you know it blocks somehow.

 

[Arkless]

Hm, that guy found a smart alternative. Checking the towerline instead of the creepline. Doesn't really work for a maze around a checkpoint though. Yet you are able to detect a circle in there. Though, if the towerline splits up, it'll slowly become harder.
Oh well, add all checked towers to an unit group and if it circles, you know it blocks somehow.

Wich is still a pretty old method, and it only works in a limited space OR is so slow that you cant do shit with it. I found a faster way in wc3 already, in case you are interested I could explain it... but you will never ever reach the speed of the built in function for that (except if you use a bigger scale for your pathing grid/use another pathing system).

 

[Frozenwind]

I'm a physcian/mathematician, so yes, I'm always interested in stuff like this

One time I tried to create a "custom maze TD" (wc3) in which people could draw their only creeping lines. The checktrigger (or algorithm, if it's officially called like that) simply always went straight forward unless it was unable to do so. I was also making it advanced making it find any solution (so not only go straightforward, but also turn left/right and create a new array for it), but that made people get like 3x the same circle and then go to the end, lol. Custom circle TD? xD

Oh well, everything is possible if you take your time. For the algorithms you basically have 2 possiblities, the creepway or the towerway. If it concerns a checkpoint, a creepway will most-likely be the best option, as you can't check wall-to-wall. Yet I'm afraid there's nearly always a way to fool the system if you know how it works. Or if people build at a random spot between the 2 checkpoints (yet this means the towers hit a wall and thus a towercheck algorithm would do the job), you might need possibility "#infinity", but I guess I'm thinking into the wrong way atm.