I am facing an issue with the if statement evaluation (getting true although it is false!) gd

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:bust_in_silhouette: Asked By The_Patriot

https://ibb.co/6mgJk1q

Hi every one, I am very new about five days in Godot :slight_smile:

I am facing a critical issue with if statements I am unable to make a simple if statement execute although I am sure it is not evaluating as I know that the expresssion should return false at certain point, tried debugging and printing the value it is getting to 0 but unfortunately as the if statement runs and evaluates correctly at the first time and then it ignores that fact that it is false !!!

here the code again

func _process(delta):
if Input.is_action_pressed("MainEngine"):
	$"MainEngine".visible = true
	z -= 0.1 
	$"../METimer".start()
else:
	$"MainEngine".visible = false
	
	if z != 0:
		print (z)
		if isMEStopped == true:
			if z > 0:
				z -= 0.1
			else:
				z += 0.1
		else:
			print("timer is on")
	else:
		print (z)

I was using the Vector3 before was trying something like direction.z
then deleted the whole block and added a simple var z = 0 variable again the same

2
:bust_in_silhouette: Reply From: nwgdusr999

“that the expression should return false”. That which expression should return false? z != 0? The if/else code looks ok to me. Try this, I’m also new, but I have a feeling it might be a type thing; this output could help, if not, might help you debug also, as your issue might not be in that part of the code.

func _process(delta):
    if Input.is_action_pressed("MainEngine"):
        $"MainEngine".visible = true
        z -= 0.1 
        $"../METimer".start()
    else:
        $"MainEngine".visible = false

        print (str("z=", z))
        print (str("z!= is ", z != 0))
        print (str("z!= is ", z != 0.0))
    
        if z != 0.0:
            if isMEStopped == true:
                if z > 0:
                    z -= 0.1
                else:
                    z += 0.1
            else:
                print("timer is on")

Hi thanks for your debugging ideas,
by expression I mean if z != 0:
look at the output it loops although it is getting to 0 but the expression is not evaluating it properly this is the code again

func _process(delta):
if Input.is_action_pressed("MainEngine"):
	$"MainEngine".visible = true
	z -= 0.1 
	$"../METimer".start()
else:
	$"MainEngine".visible = false
	print (str("z=", z))
	print (str("z!= is ", z != 0))
	print (str("z!= is ", z != 0.0))
	if z != 0:
		print (z)
		if isMEStopped == true:
			if z > 0:
				z -= 0.1
			else:
				z += 0.1
		else:
			print("timer is on")

and here is the output I had to remove some parts so it is shorter

z=0
z!= is False
z!= is False
z=0
z!= is False
z!= is False
z=-4.2
z!= is True
z!= is True
-4.2
timer is on
z=-4.2
z!= is True
z!= is True
-4.2
timer is on
z=-4.2
z!= is True
z!= is True
-4.2
timer is on
z=-4.2
z!= is True
z!= is True
-4.2
z=-3.9
z!= is True
z!= is True
-3.9
z=-3.8
z!= is True
z!= is True
-3.8
z=-3.7
z!= is True
z!= is True
-3.7
z=-3.6
z!= is True
z!= is True
-3.6
z=-3.5
z!= is True
z!= is True
-3.5
z=-3.4
z!= is True
z!= is True
-3.4
z=-3.3
z!= is True
z!= is True
-3.3
z=-3.2
z!= is True
z!= is True
-3.2
z=-3.1
z!= is True
z!= is True
-3.1
z=-3
z!= is True
z!= is True
-3
z=-2.9
z!= is True
z!= is True
-2.9
z=-2.8
z!= is True
z!= is True
-2.8
z=-2.7
z!= is True
z!= is True
-2.7
z=-2.6
z!= is True
z!= is True
-2.6
z=-2.5
z!= is True
z!= is True
-2.5
z=-2.4
z!= is True
z!= is True
-2.4
z=-2.3
z!= is True
z!= is True
-2.3
z=-2.2
z!= is True
z!= is True
-2.2
z=-2.1
z!= is True
z!= is True
-2.1
z=-2
z!= is True
z!= is True
-2
z=-1.9
z!= is True
z!= is True
-1.9
z=-1.8
z!= is True
z!= is True
-1.8
z=-1.7
z!= is True
z!= is True
-1.7
z=-1.6
z!= is True
z!= is True
-1.6
z=-1.5
z!= is True
z!= is True
-1.5
z=-1.4
z!= is True
z!= is True
-1.4
z=-1.3
z!= is True
z!= is True
-1.3
z=-1.2
z!= is True
z!= is True
-1.2
z=-1.1
z!= is True
z!= is True
-1.1
z=-1
z!= is True
z!= is True
-1
z=-0.9
z!= is True
z!= is True
-0.9
z=-0.8
z!= is True
z!= is True
-0.8
z=-0.7
z!= is True
z!= is True
-0.7
z=-0.6
z!= is True
z!= is True
-0.6
z=-0.5
z!= is True
z!= is True
-0.5
z=-0.4
z!= is True
z!= is True
-0.4
z=-0.3
z!= is True
z!= is True
-0.3
z=-0.2
z!= is True
z!= is True
-0.2
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True
0
z=-0.1
z!= is True
z!= is True
-0.1
z=0
z!= is True
z!= is True

The_Patriot | 2019-05-22 19:17

I have also flipped the logic like this

unc _process(delta):
if Input.is_action_pressed("MainEngine"):
	$"MainEngine".visible = true
	z -= 0.1
	$"../METimer".start()
else:
	$"MainEngine".visible = false
	print (str("z=", z))
	print (str("z == is ", z == 0))
	print (str("z == is ", z == 0.0))
	if z == 0:
		print ("expression is true")
	else:
		print ("expression is false")
		if isMEStopped == true:
			if z > 0:
				z -= 0.1
			else:
				z += 0.1
		else:
			print("timer is on")

there are two bugs I think

  1. the editor returns false print for (!=)
  2. the float expressions are evaluated oppositely sometimes

The_Patriot | 2019-05-22 19:29

As workaround I had to use this expression if z < 0.1 && z > -0.1: instead
read another thread that it is because of the floating point are not showing fully in the editor, hope the developers will solve this soon

Thanks for all of you

The_Patriot | 2019-05-22 19:41