Recreating ACS Vector Angle script to Zscript

[andreboomer]

I'm using the link below:
https://zdoom.org/wiki/VectorAngle

I want to recreate the ACS script used in the example above, but in zscript. So Specifically I'm not relying on a TID but a pointer to the nearest actor/target.

For example with the line:
vang = VectorAngle (GetActorX (1) - GetActorX (0), GetActorY (1) - GetActorY (0));

I would like to replicate that in zscript, I was thinking maybe with DeltaAngle using pointers such as "Owner" to represent player and "Target" to represent a nearby actor.
Could anyone help me out, i'd greatly appreciate it.

[m8f]

There is a function for the Actor class:

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clearscope double AngleTo(Actor target, bool absolute = false) const

Isn't it what you want?

[andreboomer]

There is a function for the Actor class:

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clearscope double AngleTo(Actor target, bool absolute = false) const

Isn't it what you want?

this is what I came up with(not a coder by trade, so I'm probably way off)
vang = deltaangle(owner.angle, AngleTo(target));

but this line crashes the game. I'm stumped honestly.

[m8f]

Try

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vang = deltaangle(owner.angle, owner.AngleTo(target));

or maybe just

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vang = owner.AngleTo(target);

[Graf Zahl]

but this line crashes the game. I'm stumped honestly.

It crashes how? You got to be a bit more informative here if you need help.

[Rachael]

Do make sure also to check the nullptrs for both owner and target - ZScript will not check them for you and will crash if you attempt to utilize a null actor object.

[andreboomer]

but this line crashes the game. I'm stumped honestly.

It crashes how? You got to be a bit more informative here if you need help.

Ok so this is basically what I wrote

Line495: Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(target));
Let angle = (TargetAngle - owner.angle + 1.0) % 1.0;


Then as a conditional statement I wrote
if(owner.angle < 0.2 || owner.angle > 0.8) ;
int sx 320 = 320 - (320*Sin(angle)/Cos(angle);

All of this is within a ModifyDamage() function.

The error pops up with the game running as:
VM execution aborted:tried to read from address zero. In function parameter targ
the next line saying where it's called from which is line : 495

Do make sure also to check the nullptrs for both owner and target - ZScript will not check them for you and will crash if you attempt to utilize a null actor object.

I do think it is from the pointers that the error exists.

[Rachael]

The error pops up with the game running as:
VM execution aborted:tried to read from address zero. In function parameter targ
the next line saying where it's called from which is line : 495

Do make sure also to check the nullptrs for both owner and target - ZScript will not check them for you and will crash if you attempt to utilize a null actor object.

I do think it is from the pointers that the error exists.

That is exactly what I was talking about.

You are not checking for the existence of target.

Try this:

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if (target != null && owner != null)
{
    Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(target));
    Let angle = (TargetAngle - owner.angle + 1.0) % 1.0;
}

[andreboomer]

The error pops up with the game running as:
VM execution aborted:tried to read from address zero. In function parameter targ
the next line saying where it's called from which is line : 495

Do make sure also to check the nullptrs for both owner and target - ZScript will not check them for you and will crash if you attempt to utilize a null actor object.

I do think it is from the pointers that the error exists.

That is exactly what I was talking about.

You are not checking for the existence of target.

Try this:

Code: Select all

if (target != null && owner != null)
{
    Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(target));
    Let angle = (TargetAngle - owner.angle + 1.0) % 1.0;
}

Where would it be best to check "if(owner.angle < 0.2 || owner.angle > 0.8)"

Could I call it from DoEffect()?

and if if(owner.angle < 0.2 || owner.angle > 0.8)" is true, could I create a bool to return true once the condition is met?

[Rachael]

I'm trying to explain to you about null pointers and you're still going on about checking actor properties without even checking if they exist first.

Well - I did what I could to help you, I even provided you with some code. It's all in your hands, now.

[andreboomer]

I'm trying to explain to you about null pointers and you're still going on about checking actor properties without even checking if they exist first.

Well - I did what I could to help you, I even provided you with some code. It's all in your hands, now.

Oh my bad for not clarifying, I did null check the pointers after you told me to. It runs now, but the script currently is doing nothing. Im assuming because it isn't being called correctly.

Bool SeeYou;

Override Void Doeffect()
{
if (target != null && owner != null)
{
Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(target));
Let angle = (TargetAngle - owner.angle + 1.0) % 1.0;
if(owner.angle < 0.2 || owner.angle > 0.8)
{
int sx = 320 - (320 * Sin (angle) / Cos (angle));
Seeyou = true;
}
else
{
Seeyou = false;
}
}
super.DoEffect();
}

I think using DoEffect() to check if the Bool is true, and if it's true check for it in the modify damage function?

Override Void ModifyDamage (int damage, Name damageType, out int newdamage,
bool passive, Actor inflictor, Actor source, int flags)
if (passive && damage > 0)
{
if(seeyou == true)
{
DoStuff();
A_PrintBold("Works!");
}
}

I understand if you can't help me further, I still appreciate what you were able to provide so that I could progress forward.

[m8f]

Target! The item doesn't have a target, the owner has.

try

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if (owner != null && owner.target != null)
{
Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(owner.target));

[andreboomer]

Target! The item doesn't have a target, the owner has.

try

Code: Select all

if (owner != null && owner.target != null)
{
Let TargetAngle = deltaangle(owner.angle, owner.AngleTo(owner.target));

Yea it was the pointers, thanks to everyone for the help.