How to Give a unit the ability to fly

[Magtheridon96]

Unit Flying Ability
(The Right Way)

Table of Contents

• Introduction
• The Problem
• The Solution
• Tips
• Wrap-Up

Introduction

This is quite a simple tutorial. I made it quite short and straight to the point because there's
not much to say. Basically, what we've been doing to give units the ability to fly is wrong.
Some Jass coders already know this, but most GUI coders don't.

The Problem

Most GUI coders do this to give a unit the ability to fly:

GUI Basic Method

• Unit - Add Crow Form to SomeUnit
• Unit - Remove Crow Form from SomeUnit

This is wrong..
Why? Because:

Assume you have a unit that has the ability 'Arav' (Raven Form/Crow Form).
Now, if we were to add the ability to this unit, the function would fail this attempt and
UnitAddAbility will return false. After we remove the ability (In the second
line of the GUI method), the original 'Arav' ability will be removed.

We can conclude that the GUI method is unsafe, bug-prone and WRONG!

The Solution

As I mentioned before, UnitAddAbility will return false if the ability adding has failed.
We can take advantage of this to write a snippet that attempts to add the ability, checks if the ability
was added, and if it was, the ability will be removed. Luckily, we can do this with no overhead at all.

Or, you can simply check the level of the ability. If it's 0, add and remove the abilities.
If not, do nothing. (No! Don't use the action 'Do Nothing' because all it does is slow you down!)

GUI Method (Fixed)

• If (All Conditions are True) then do (Then Actions) else do (Else Actions)
  • If - Conditions
    • (Level of Crow Form for Unit) Equal to 0
  • Then - Actions
    • Unit - Add Crow Form to Unit
    • Unit - Remove Crow Form from Unit
  • Else - Actions

But, I'd strongly recommend to Always use this faster, safer and better method instead:

GUI Method (Faster)

• Custom script: if UnitAddAbility(udg_Unit,'Amrf') then
• Custom script: call UnitRemoveAbility(udg_Unit,'Amrf')
• Custom script: endif

Those three lines would attempt to add the ability to the unit.
If the condition (UnitAddAbility) returns false, the ability won't be removed. If it returns true,
the ability will be removed.

Tips

• If you're making a map, you can totally avoid these checks by
  creating an alternate crow form ability that you'll never use. (Credits to noob)
• Some people use 'Amrf', some use 'Arav', there's pretty much
  no difference. If you're a GUIer and you're not sure what those are,
  they're codes that correspond to each ability.
• This method should be applied for ALL abilities.

Wrap-Up

That's pretty much it. I hope you like this short but informing tutorial and I hope you
won't be making the mistake of blindly adding and removing unit abilities again.
Thank you for reading.

~Magtheridon96

 

[Bannar]

No matter how short it is (although it could be added into other GUI tips tutorial), if the meaning is important - and I'm sure it is - I vote for approval.

 

[Magtheridon96]

I think the curve ->

~Magtheridon96

sold it

 

[Jazztastic]

I think the curve ->

sold it

God I wish I had spread enough rep around to rep you again.

 

[Luorax]

Yea, nice tutorial for GUI users - length is really not something that matters, but usefulness. (I used to use the "bad method" too when I was a beginner [GUI] triggerer Sad story)

However I still consider the simple AutoFly snippet more easy and more useful

 

[Magtheridon96]

The curve really DID sell it ^^

 

[The_Silent]

You could really do this without using custom scripts

 

[Luorax]

• Actions
  • If (All Conditions are True) then do (Then Actions) else do (Else Actions)
    • If - Conditions
      • (Level of Crow Form for (Triggering unit)) Equal to 0
    • Then - Actions
      • Unit - Add Crow Form to (Triggering unit)
    • Else - Actions

There you go. But that custom script is faster, it's only 3 lines of JASS script, and you know what it does. But obvisouly you have to decide which method you wanna use.

 

[Magtheridon96]

Thank you Luorax
~Updated

 

[baassee]

The GUI version is not needed in this case whatever you may say. Just mention it but also show the JASS conversions of both methods (GUI/JASS) and they will see the amount of extra calls (in this case 2 but whatever).

 

[Magtheridon96]

You're probably right
I dont have the WE right now, so I'll just guess what functions are called xD

I think this:

• If (All Conditions are True) then do (Then Actions) else do (Else Actions)
  • If - Conditions
    • (Level of Crow Form for SomeUnit) Equal to 0
  • Then - Actions
    • Unit - Add Crow Form to SomeUnit
    • Unit - Remove Crow Form from SomeUnit
  • Else - Actions

is converted to this:

function SomeReaaaaaaaallyLongFunctionName0001001 takes nothing returns boolean
    return not (GetUnitAbilityLevelSwapped('Arav',udg_SomeUnit) == 0) == false
endfunction

function TheActionslol takes nothing returns nothing
    if SomeReaaaaaaaallyLongFunctionName0001001() then
        call UnitAddAbilityBJ('Arav',udg_SomeUnit)
        call UnitRemoveAbilityBJ('Arav',udg_SomeUnit)
    else
    endif
endfunction

Something like that

 

[Bannar]

You probably know that this condition

function SomeReaaaaaaaallyLongFunctionName0001001 takes nothing returns boolean
    return not (GetUnitAbilityLevelSwapped('Arav',udg_SomeUnit) == 0) == false
endfunction

Looks actually in GUI much worse XD

 

[Magtheridon96]

Actually, it's a fact that all if conditions look like that, but trigger conditions are an EPIC FAIL XD

function Conditions takes nothing returns boolean
    if (not (0==1)) then
        return false
    endif
    return true
endfunction

Actually Blizzard is smart cause they didnt do this:

function Conditions takes nothing returns boolean
    if (not (0==1)) then
        return false
    else
        return true
    endif
endfunction

lol

 

[baassee]

Not that smart though...

 

[Magtheridon96]

I think they did this on purpose :/
They probably wanted to make GUI slow so that they could force serious wc3 modders to use JASS (I'm on to you Blizzard! )

 

[The_Silent]

Actually, it's a fact that all if conditions look like that, but trigger conditions are an EPIC FAIL XD

function Conditions takes nothing returns boolean
    if (not (0==1)) then
        return false
    endif
    return true
endfunction

Actually Blizzard is smart cause they didnt do this:

function Conditions takes nothing returns boolean
    if (not (0==1)) then
        return false
    else
        return true
    endif
endfunction

lol

It doesn't actually take a genius to figure this one out, lol xD

 

[Magtheridon96]

W8!
Guys!
I think I know why Blizzard did this:

function Conditions takes nothing returns boolean
    if not (something) then
        return false
    endif
    return true
endfunction

And not this:

function Conditions takes nothing returns boolean
    if something then
        return true
    endif
    return false
endfunction

It's because a trigger's events will fire quite often, so they wanted to make sure that the actions are NOT supposed to happen first
That sux xD

They probably didnt do this:

function Conditions takes nothing returns boolean
    return something
endfunction

Because that would make conditions look lame

 

[baassee]

Or that they were just lazy enough not to think about the last one.

 

[Bannar]

Or that they were just lazy enough not to think about the last one.

Lazy? I think they were actually brain storming about condition function.

function Conditions takes nothing returns boolean
    if not (something) then
        return false
    endif
    return true
endfunction

Because it's dam hard to create such monster. Would you lose your free time to replace 3 line-script with 6 lines? I think they got well paid for that stuff - it explains everything xD

 

[baassee]

It's not even a 3 liner, it's a one-liner.

function Conditions takes nothing returns boolean
    return something
endfunction

 

[Magtheridon96]

No guys !

function Conditions takes nothing returns boolean
    if (((something==true)==true)==true) then
        // Check again to make sure :O
        if (((something==true)==true)==true) then
            // Ok now we're sure :P
            return true
        endif
        // HAHA! The Jass Interpreter was wrong >:D
        return false
    endif
    // lol something==false :ogre_hurrhurr:
    return false
endfunction

N00bs

Ok, I think we should end this argument xD

 

[noob]

hey there is already one tutorial on flying height approved http://www.hiveworkshop.com/forums/general-mapping-tutorials-278/adding-fly-height-any-unit-17790/

 

[Magtheridon96]

But that one does it incorrectly

 

[Apheraz Lucent]

Use some tips from here. Your tutorial is unattractive and plain.
http://www.hiveworkshop.com/forums/...t-tutorial-please-read-before-posting-119320/

 

[Magtheridon96]

Oh Apheraz, how mean of you D:
You made me cry :'(
...
lol jk, I'll fix it xD

edit
Updated the tutorial.
Looks much better now :3

 

[noob]

Now you changed the tutorial and added colors it is unreadable and ugly. text is not for making ugly coulours.

 

[Apheraz Lucent]

The heading colors you should use are these:
Color Test
Color Test
Color Test
Color Test
Color Test

As they fit the Hive theme perfectly, and are not pain in the behind to be seen. Alternatively, any font color should be avoided - the one that is used to write everything is good enough - white color is standing out too much.

the title

This is the wrong way of doing it.
Tips should be written in colors that stand out, if any.

The Title

This is the right way of doing it.
Tips should be written in small letters, if any.

For color codes, just quote this message and copy them.
And that orange is okay, but please, no white in the tutorial.
There should also be "Tips & Hints" with some extra information, or maybe "Suggested Readings". Also, Content of tutorial won't hurt.

 

[Adiktuz]

Red hurts the eyes... and dark blue is hard to read...

anyway, this is helpful for those GUIers out there...

 

[Apheraz Lucent]

If you red what I wrote, you would clearly notice "This is the wrong way" part.
Anyways, Magtheridon96, what you plan on doing? Something new, instead of aesthetic appearance? Maybe, you could go with a Jass version, too, like a bonus feature.

 

[baassee]

Red is awesome to put out warnings. Hehe.

 

[noob]

I finaly understanded why units with crow form are able to change height it is simply because when they cast the spell they make the morph anim, change height and after become the new unit.
Another way to do what you do without check just create one new ability only for the trick based on crow form.
and when you want to change the heigt of an unit add and remove this ability.
Because no unit have this ability there is no problem.
This tutorial is partially jass so change it category to jass.
Because gui section is for the ones who does not know jass.

 

[Magtheridon96]

Another way to do what you do without check just create one new ability only for the trick based on crow form.
and when you want to change the heigt of an unit add and remove this ability.
Because no unit have this ability there is no problem.

True, but in public resources, it would be troublesome.
For a map, that makes sense.
Using the check can still save some space though.

 

[Apheraz Lucent]

The tutorial now has proper coloration and heading, and it also displays useful information that aren't seen in other tutorials.

I'm looking forward to see this approved.

 

[Magtheridon96]

The tutorial now has proper coloration and heading

lol You posted that while I was editing the tutorial
How does it look now? ^^

 

[Apheraz Lucent]

One of colors that fit the Hive the most. Nice, and not painful for the eyes. But, now the red stands out too much. Tried with yellow/dark yellow? It would fit the theme and still draw attention, if your aim is to get a cohesive coloration.

Anyways, don't bold the red lines. Use this, this or this instead, with no colors at all, or use pure colors.

 

[Magtheridon96]

That's true.
Updated.

 

[Apheraz Lucent]

Sigh... We aim for perfection, but we can't see it's a moving target.

Aesthetically very good, the concept of tutorial is good as well, and the whole tutorial is useful.

Good Job, I have to say.

Oh, the only thing you can do now is to use points. The points will link your table of contents, and when you click, for an example, "Tips", the page will scroll down to that point.
If you need help with points implementation, ask me via Pm / Vm.

 

[Bribe]

You should use 'Amrf' instead of 'Arav' as 'Amrf' is from Medivh which is not as common as 'Arav' which is from a DoT.

 

[PurgeandFire]

Nice updates.

~Approved.

 

[gorillabull]

yea.. i have a question: if a unit is set to have Fly Movement type in the Object editor then why does not the function "set flying height" work?? you would have to set it to zero first and then change it or sometimes that does not work either is it a bug?

 

[Magtheridon96]

Warcraft III has a ton of bugs :/
I guess the most ideal thing to do is to give all units Foot Movement type.
If you want flying units, just detect when a unit of a certain type enters the map and give it a flying height

 

[gorillabull]

hmm im gonna try that

 

[Magtheridon96]

I wrote a system for this: http://www.hiveworkshop.com/forums/submissions-414/snippet-flyheight-214371/