What am I doing wrong(pathfinding)

Somar

func _pathFinding(start, goal):
	var openList = []
	var closedList = []
	openList.append([start, 0, _h(start, goal), _f(start, goal)])

	while not openList.empty():
		var m = _m(openList)
		if m == goal:
			print("End of pathfinding at: " + String(goal / 8))
			closedList.append(m)
			for i in closedList:
				if not i == goal:
					var mark = O.instance()
					get_node("/root/Title/TileMap").add_child(mark)
					mark.position = i
					mark.add_to_group(mark_group)
			return closedList
		closedList.append(m)
		openList.pop_front()
		print(m[1])
		for n in _sides(m):
			if closedList.has(n):
				continue
			var cost = int(_g(n) + _distance(m, n))
			print("Cost of: " + String(n / 8) + " is: " + String(cost))
			for i in openList:
				if i[0] == n:
					openList.erase(i)
				elif cost > m[1]:
					continue
			if closedList.has(n):
				closedList.erase(n)
			elif cost < _g(n):
				continue
			openList.append([Vector2(n.x, n.y), cost, _h(n, goal), _f(n, goal)])
func _m(array):
	var minV = 9999
	var vec
	for i in array:
		if i[2] < minV:
			minV = i[2]
			vec = i[0]
	return vec
func _f(node, goal):
	return _g(node) + _h(node, goal)
func _h(node, goal):
	var dx = abs(node.x - goal.x)
	var dy = abs(node.y - goal.y)
	return (dx + dy) 
func _distance(a, b):
	var dx = abs(a.x - b.x)
	var dy = abs(a.y - b.y)
	return int(dx + dy) 
func _g(node):
	var c
	if get_node("/root/Title/TileMap").map.get_cellv(get_node("/root/Title/TileMap").map.world_to_map(node)) == 12:
		c = 7
	elif get_node("/root/Title/TileMap").map.get_cellv(get_node("/root/Title/TileMap").map.world_to_map(node)) == 11:
		c = 1
	else:
		c = 1
	return c
func _sides(node):
	var s = [Vector2(0, -8), Vector2(-8, 0), Vector2(0, 8), Vector2(8, 0)]
	var childN = [(node + s[0]), (node + s[1]), (node + s[2]), (node + s[3])]
	return childN

I am getting wrong numbers and the character is not avoiding higher cost tiles. ´var cost´ always returns me the value 9 or 15, while those make no sense. Sorry for anything if it appears to be dumb. It is my first try at complex code.

I wasn't able to make the code formatation for the entire code for some reason.

TwistedTwigleg

@Somar said: I wasn't able to make the code formatation for the entire code for some reason.

There are a few ways to format code here on the forums.

For a single line of code, you can add the character shared on the Tilda (~) key to each end and that will format the code. It looks like this: Single line. For better or for worse, this only works for single lines of code, and doesn't really format correctly with multiple lines.

Another way to mark a single line of code is by adding <code> and </code> HTML, though it just renders the code exactly the same as using the character shared on the Tilda key.

For multiple lines of code, you just need to indent all of the code with a single tab and then it will be rendered as a single code block. Something like this:

var test = "hello"
print (test + " world")

Feel free to click the "Quote" button to see how I formatted the code in this post. I edited your post and added a single tab to all of the code so it renders correctly, since there is quite a bit of code to look at. Hopefully this helps! :smile:

Schorsch

That is alot of code. Noone wants to read 66 lines of code and try to understand what you thought by implementing this. That is really alot of work. Things you can do: - Start to debug your code. You can put print statements in your code to check some values at runtime. Try to think about how a value should look like. If anything looks odd, investigate it. - Better than printing values is to use a debugger. I know that Godot has some debugging tools, but i am new to Godot by myself and didn't used them yet. Normally a debugger is able to set Breakpoints. That means, if the code execution hit's a breakpoint, the program is paused and you can look at variables and memory at this time. A debugger is able to execute code step by step so that you can see how values change over time.

So with a debugger, you can check values like with print statements, but more powerful. You can pause code, decide what you want to see while you are debugging and running the code and so on.

With that, you should be able to find your problems.

Otherwise. It seems like you are implementing A*. Godot has utilities for pathfinding, so you don't have to implement this by yourself. I don't know if this is able to have different costs, but i would be surprised if not.

Also, try to find better names for your functions. If someone tries to read and understand your code and sees a function name like "_m", it is not clear what this function does. I know, some of your namings a like many people name them in A*, "f(), g() and h()" but that are no good names. Try to name functions after what they do. That helps others to understand your code, and even yourself, if you need to look at your own code after a long time.

Somar

Thanks, TwistedTwigleg. I will remember that for the next topics.

Schorsch, I am trying to do that at this moment. The code I posted here has lots of print lines on it. But they were being used to help me finish it. The program runs, and they do their function, but they are not really necessary at this point. So I took them out.

I took the time to look at what I am trying to do from another angle. When I started this project I had zero knowledge of Godot and GDScript and I am also pretty amateur when it comes to programming in general. The guys at discord where really helpful, but the documentation really doesn't help at all. It has lots of technical jargons that are really difficult to be understood for someone that is just starting with programming. In that, and only that, I miss Game Maker Studio 2.

When I wrote this code I was trying to make it work for the past three weeks. And I had it almost entirely on my head, and so I forgot to put in notes and make better function and variable names. I let it sitting in my office for a few weeks because I had too much work to do and when I came back I couldn't understand a thing and had to try to read it all over again. So I'll keep in mind notes and better naming from now on.

Thanks for the help guys. I decided to take a different approach to this. I wrote this code relying on some codes I found in the google. But now I am trying to write it all by myself.

Schorsch

It is a good idea to write code by yourself. But really, think about just using godots path-finding. If you need help with this, just ask. I am new to godot by myself. I bought a course on the internet about godot and they teahed me alot of things about it. That was really helpful. Maybe think about that too. Otherwise aks here and i will try to help you.