Homing Missile Problem

10-18-2007, 06:06 AM

(Don't worry about the spell request thread, it has not been forgotten)
I set to work about an hour ago on a homing missile system, as a companion for my Chain Lightning System on the Hive. Anyways, the missiles, when using a formula to decide weather to move the missiles either left or right, go crazy. I'm not exactly sure how to describe it - they home towards the target, but then will circle around after reaching him, and if they go at 0 degrees, they go straight and do not change their angle. Attached is the map, because I don't think my description will do.

Attached Files

Missile System.w3x (38.0 KB)

10-19-2007, 10:24 PM	#2
Dil999	Er.. bump?

10-19-2007, 11:51 PM	#3
TaintedReality	Posting the code instead of the map = more replies :).

10-20-2007, 12:37 AM	#4
Dil999	Its impossible for me to describe the problems that are occurring without posting the map...

10-21-2007, 11:10 PM	#5
Blackroot	Then post both .

10-21-2007, 11:48 PM

legend_tisman

JASS:

//TESH.scrollpos=6
//TESH.alwaysfold=0
struct HMData
    real x
    real y
    real angle
    effect e
    unit target
    unit caster
    real turnrate
    real maxspeed
    real speed
    real acceleration
    unit missile
endstruct

function HomingMissile_Timer takes nothing returns nothing
    local timer t = GetExpiredTimer()
    local HMData hm = HMData(GetAttachedInt(t,"hm"))
    local real x = GetUnitX(hm.target)
    local real y = GetUnitY(hm.target)
    local real angle = hm.angle
    local real angle2 = bj_RADTODEG * Atan2(y - hm.y,x - hm.x)
    local real r
    
        set r = angle - angle2

        if r < 0 then
            set r = r * -1
        endif
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, R2S(r) )
        
        if r > 180.0 then
            set hm.angle = hm.angle + hm.turnrate 
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "a" )
        else
            set hm.angle = hm.angle - hm.turnrate 
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "b" )
        endif
        
        if hm.angle < 0 then
            set hm.angle = hm.angle + 360.0
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "c" )
        elseif hm.angle > 360.0 then
            set hm.angle = hm.angle - 360.0
       call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "d" )
       endif
   
        if hm.speed >= hm.maxspeed then
            set hm.speed = hm.maxspeed
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "e" )
        else
            set hm.speed = hm.speed + hm.acceleration
        call DisplayTimedTextToForce( GetPlayersAll(), 10.00, "f" )
        endif
        
    set hm.x = hm.x + hm.speed * Cos(hm.angle * bj_DEGTORAD)
    set hm.y = hm.y + hm.speed * Sin(hm.angle * bj_DEGTORAD)
    call SetUnitX(hm.missile,hm.x)
    call SetUnitY(hm.missile,hm.y)
        
        
    
    set t = null
endfunction

function HomingMissile takes real startx, real starty,real z,real startspeed,real startangle, string missilepath,real missilesize,unit caster,unit targetunit,real maxturnrate,real maxspeed,real acceleration returns nothing
//startx, starty, z,startspeed, startangle, missilepath, missilesize, caster, targetunit, maxturnrate, maxspeed, acceleration
//call HomingMissile(0.0,0.0,60.0,300.0,180.0, "Abilities\\Weapons\\SpiritOfVengeanceMissile\\SpiritOfVengeanceMissile.mdl",1.0,gg_unit_H001_0002,gg_unit_H001_0002,60.0,600.0,100.0)
    local HMData hm = HMData.create()
    local timer t = CreateTimer()
    set hm.missile = CreateUnit(Player(0),'h000',startx,starty,startangle)
    set hm.caster = caster
    set hm.angle = startangle
    set hm.x = startx
    set hm.y = starty
    set hm.speed = startspeed * 0.04
    set hm.target = targetunit
    set hm.turnrate = maxturnrate * 0.04
    set hm.maxspeed = 20//maxspeed * 0.04
    set hm.acceleration = acceleration * 0.04
    set hm.e = AddSpecialEffectTarget(missilepath,hm.missile,"origin")
    call SetUnitFlyHeight(hm.missile,z,0)
    call SetUnitScale(hm.missile,missilesize,missilesize,missilesize)
    call AttachInt(t,"hm",hm)
    call TimerStart(t,1.15,true,function HomingMissile_Timer)
    set t = null
endfunction

so far it seems the problem has been solved so ill give up trying to fix it ><

10-22-2007, 12:59 AM

Ammorth

Fixed your problem. Not sure what you were doing, but its working now. Changed the code to work with angles between -180 and 180. I find these angles easier to use. You are welcome to change it as you like, just keep in mind the GetAngleDifference() function returns between -180 and 180.

You still have a problem where a hero can stand inside the missiles max turn "circle" and not get hit, not sure how you want to deal with this.

I would personally convert to vector math, since it should be faster, and easier to use.

Attached Files

Missile System.w3x (38.8 KB)

10-22-2007, 08:29 PM	#8
Dil999	Thanks ammorth, +rep