[JASS] Swarm Function

[Herman]

I just started learning JASS, and wanted to do a simple function for a spell I was making

I do not have JassCraft (using a computer that isn't mine), so I need to know the proper syntax for this code

function Swarm takes real x, real y, real r, integer n, unit-type unit returns nothing
local real DegreesBetween = 360/n
local real D = 0
loop
exitwhen n==0
D = D + DistanceBetween
CreateUnit(x + (cos(D) * r), y + (sin(D) * r), unit)
n = n -1
endloop
endfunction

I'm not sure exactly what the syntax is, but I assume it is something similar to that
Also, I haven't added a bit for making the unit face the center (not sure wah tthe syntax is) but I imagine it's just setting unit facing = to D - 180
If somebody could also tell me the syntax for changing their facing that would be good too
(I will give +rep)

 

[GhostWolf]

What are you trying to make ?

About the angle, do this to make a unit turn backwards:

call SetUnitFacing(yourUnit) = GetUnitFacing(yourUnit) - 180

If you want a unit to face a point, you can use the AngleBetweenPoints function but its not suggested.
Its usually better to use your own coordinates-based angle function.

Here are two usefull basic functions you'll probably want in your JASSing:

//****************************************************************************************
//               Distance between two points using coordinates
// call DistanceBetweenCoordinates(real x1, real y1, real x2, real y2)

function DistanceBetweenCoordinates takes real x1, real y1, real x2, real y2 returns real
    local real dx = x1 - x2
    local real dy = y1 - y2
    return SquareRoot(dx * dx + dy * dy)
endfunction

//****************************************************************************************
//               Angle between two points using coordinates
// call AngleBetweenCoordinates(real x1, real y1, real x2, real y2)

function AngleBetweenCoordinates takes real x1, real y1, real x2, real y2 returns real
    return bj_RADTODEG * Atan2(y2 - y1, x2 - x1)
endfunction

 

[Herman]

Heh

Whoops forgot to give enough info

The function is supposed to create a circle of units evenly spaced out and equidistant from the origin

x,y is the origin of the circle
r is the radius
n is the number of units
unit is supposed to be the unit type, but I have no idea how it should work in JASS (I don't have JassCraft or strong knowledge of the syntax)

function Swarm takes real x, real y, real r, integer n, unit-type unit returns nothing
local real DegreesBetween = 360/n //Finds the degrees between each unit
local real D = 0                           //allocates memory for the (Degrees) of each unit's polar coordinates
loop
exitwhen n==0
set D = D + DistanceBetween //Each loop adds another fraction of the degrees, spacing the units out evenly
call CreateUnit(x + (cos(D) * r), y + (sin(D) * r), unit) //I am not sure what this code is supposed to be, but it is the mathematical function to find polar coordinates
call SetUnitFacing(bj_last_Created()) = D - 180 //Makes the units face the center
set n = n -1                                      //with each loop, n drops, and the loop will exit when n = 0
endloop
endfunction

 

[GhostWolf]

set D = D + DistanceBetween

I guess you meant AngleBetween ?

call CreateUnit(x + (cos(D) * r), y + (sin(D) * r), unit)

This should be like this:

call CreateUnit(player owner, integer rawcode, real x, real y, real facing angle)

So for what you want you'll do something like this

call CreateUnit(somePlayer, someRawCode, x + r * cos(D), y + r * sin(D), someAngle)

 

[Herman]

Heh

I downloaded JASScraft to a flash drive, and then reviewed it on another computer that has wc3 installed

heres the finished

function Swarm takes player owner, integer unitid, real x, real y, real r, integer n returns nothing
local real DegreesBetween = 360/n
local real D=0
loop
exitwhen n==0
set D = D + DegreesBetween
call CreateUnit(owner, unitid, (x + (Cos(D * bj_DEGTORAD)*r)), (y + (Sin(D * bj_DEGTORAD)*r)), D - 180)
set n = n - 1
endloop
endfunction

Not too user friendly, but comes out looking really cool when you use it (try 45 units at a radius of 1000)