"How do I ZScript?"

Ask about ACS, DECORATE, ZScript, or any other scripting questions here!

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Blue Shadow
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Re: "How do I ZScript?"

Post by Blue Shadow »

ramon.dexter wrote:How do I use random number in Damage property of projectile? When i put in 'random(1,10);', it returns error, that even numbers has to be used :(
Use DamageFunction instead of Damage as the property.
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Major Cooke
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Re: "How do I ZScript?"

Post by Major Cooke »

Just be warned, changing the damage from then on out will remove the damagefunction and it'll be based on damage*1d8! At least that's what it looks like from the source code.
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cambertian
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Re: "How do I ZScript?"

Post by cambertian »

If I'm trying to make an inventory item that should only be picked up if, say, the player doesn't have item X in his inventory, which virtual function should I override - HandlePickup, TryPickup, TryPickupRestricted, CanPickup, or ShouldStay?
I've been trying HandlePickup already, but even when it returns false it seems to get added to the inventory...
ZippeyKeys12
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Re: "How do I ZScript?"

Post by ZippeyKeys12 »

Is it possible to detect multiple simultaneous key-presses inside of InputProcess? Set booleans when buttons are pressed and remove when released—Thanks Gutawer

Also is it possible to register an EventHandler while the game is running? I recall seeing ZZYZX mention this, but I can't seem to figure it out. :?

Any help would be appreciated :)

EDIT: Also, is it not possible to put a constant array in a struct?
EDIT 5: Can I access a variable in an EventHandler from my StatusBar?

EDIT 2: Is there no way to do exponents? exp(x) is only e^x ** Operator—Thanks Gutawer again
EDIT 3: I guess I know nothing. Does cos(x) have a relatively significant performance cost like sqrt(x)? Don't bother micro-optimizing—Thanks Gutawer again
EDIT 4: And is there a way to get pi? Set it as a constant because it's close enough—Thanks Apeirogon
Last edited by ZippeyKeys12 on Sun Nov 05, 2017 7:45 pm, edited 2 times in total.
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Apeirogon
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Re: "How do I ZScript?"

Post by Apeirogon »

ZippeyKeys12 wrote: EDIT 4: And is there a way to get pi?
TL:DR Just define its as constant.
Pi is irrational transcendent number and cant be evaluate like 2+2, just approximately defined to some decimal number. Even if you planing use eulers identity to find n roots of number (why?),pi=3.141596 and e=2.718281828 would be more than satisfaing aproximation, because other number in gzdoom may, and would, be defined with musch less precision.

How make a_chase function more "intelligent", because, as example, monster hard to find entrance into small corridor where stand player?
ZippeyKeys12
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Re: "How do I ZScript?"

Post by ZippeyKeys12 »

Apeirogon wrote:How make a_chase function more "intelligent", because, as example, monster hard to find entrance into small corridor where stand player?
If you're making a map then check this out:viewtopic.php?f=105&t=58168 else idk maybe try using hitscans or actors to try and plot out the map and try every path to find the player?
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Gutawer
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Re: "How do I ZScript?"

Post by Gutawer »

ZippeyKeys12 wrote: EDIT 2: Is there no way to do exponents? exp(x) is only e^x
EDIT 3: I guess I know nothing. Does cos(x) have a relatively significant performance cost like sqrt(x)?
2: Use the ** operator.
3: Even sqrt() doesn't have a massive performance impact unless you're calling it a lot, so I wouldn't assume that cos() has any significant performance impact either. Don't try and optimise until your code is running slowly, because otherwise you get messy micro-optimised code which is a pain to read.
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ramon.dexter
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Re: "How do I ZScript?"

Post by ramon.dexter »

OK, how does replaces excatly work in zscript?

Let's say, I have a weapon, here:

Code: Select all

class staffBlaster : Weapon replaces RocketLauncher
But I can find rocket launcher where it should be in map (better said: It is not replaced). Relacers for rocketammo works as expected, replacers for other weapons work as expected, but the replacer for rocketlauncher just dont work. What am I doing wrong?
Blue Shadow
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Re: "How do I ZScript?"

Post by Blue Shadow »

Are you loading other mods with yours that replace the rocket launcher (especially ones which to so via DECORATE)?
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ramon.dexter
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Re: "How do I ZScript?"

Post by ramon.dexter »

No. I'm testing the mod only with basic doom2. And it really suprises me, since the shotgun IS replaced, the armor is replaced, but the rocketlauncher sits there and smiles on me :)
ZippeyKeys12
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Re: "How do I ZScript?"

Post by ZippeyKeys12 »

Is your rocket launcher in a separate file that you forgot to #include?
Maybe something is left over in AutoLoad?
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ramon.dexter
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Re: "How do I ZScript?"

Post by ramon.dexter »

Yup. forget to remove the rocketlaucnher replacer/remover that I put in and completely forgot about :)
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Rip and Tear
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Re: "How do I ZScript?"

Post by Rip and Tear »

What is the practical effect of the identifier in the random number functions (wiki)?
ZippeyKeys12
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Re: "How do I ZScript?"

Post by ZippeyKeys12 »

Rip and Tear wrote:What is the practical effect of the identifier in the random number functions (wiki)?
From what I can tell, it seems as if running random functions under a specific identifier could somehow bias future random functions with that same identifier. So I supposed if one needed a more independent random value they would use a different identifier? :shrug:
Gonna have to see what someone more informed has to say, I'm interested now.
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Gutawer
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Re: "How do I ZScript?"

Post by Gutawer »

The identifier determines which FRandom object is returned internally when parsing the random functions - essentially, each FRandom object is a random number generator which holds an array of "states" (20 states, if interpreted as 32-bit integers). When an RNG function is called, the internal array index is incremented, and the state at that index is returned as a random number. Each FRandom object's states are seperate from the others, meaning that RNGs with different objects act independently of each other. So:

Code: Select all

int num1 = random(0, 10);
int num2 = random(0, 10);
Console.printf("%d, %d", num1, num2);
should act the same as:

Code: Select all

int num1 = random(0, 10);
int throwaway = random[whatever](0, 10);
int num2 = random(0, 10);
Console.printf("%d, %d", num1, num2);

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