Backstab

[warden13]

How can I do "attacking unit is behind the attacked unit" condition?

 

[donut3.5]

• Backstab
• Events
  • Unit - A unit is attacked
• Conditions
  • ((Facing of (Triggering unit)) - (Facing of (Attacking unit))) Less than or equal to 90.00
  • ((Facing of (Triggering unit)) - (Facing of (Attacking unit))) Greater than or equal to -90.00
• Actions

--donut3.5--

 

[warden13]

Thank you =)

 

[Diablo-dk]

Donut, that won't work correctly. Facing of Triggering unit - Facing of attacking unit won't be returned in degrees. if one of the units are facing 10 degrees, and the other one 350. the result will be -340 or 340.

To do this correctly you will need angle calculation functions.

function IsAngleBetweenAngles takes real angle, real angle1, real angle2 returns boolean
     local real x
        set angle=ModuloReal(angle,360)
        set angle1=ModuloReal(angle1,360)
        set angle2=ModuloReal(angle2,360)
        if (angle1>angle2) then
            set x=angle1
            set angle1=angle2
            set angle2=x
        endif
        if (angle2-angle1)>(angle1 - (angle2-360)) then
            set angle2=angle2-360
            if angle > 180 then
                set angle=angle-360
            endif
            return angle>=angle2 and angle<=angle1
        endif
     return (angle>=angle1) and (angle<=angle2)
    endfunction

Though it requires a little jass knowledge.

 

[donut3.5]

Actually, I tested it and it works.
I'm pretty sure that if a degree is <0 and >360, then it will take the modulo.
If not you can take it anyways using

• (((Facing of (Triggering unit)) - (Facing of (Attacking unit))) mod 360) Less than or equal to 90.00
• (((Facing of (Triggering unit)) - (Facing of (Attacking unit))) mod 360) Greater than or equal to -90.00

--donut3.5--

 

[Diablo-dk]

The first example won't always work corectly, neither would it do with modulo. if facing of triggering unit is 350 and facing of attacking unit is 10 the value would still be 340.

 

[HINDYhat]

I don't think you need to use angle functions... my way works fine:

function IsUnitBehind takes unit Who, unit BehindWho, real Angle returns boolean
    local real d=GetUnitFacing(Who)-GetUnitFacing(BehindWho)
    if d>=180.0 then
        set d=d-360
    elseif d<=-180.0 then
        set d=d+360
    endif
    return (d<=Angle and d>=-Angle)
endfunction

The real "Angle" is just a more-or-less value of the angle difference. If this works, then I'm pretty sure that it's faster than calling angle functions and modulos.