Line Location Distance.

[Zergleb]

I was just working on my map and made some of these up. Thought I might as well post them if someone else wanted them and didn't know how to make them.

What this does is, the bottom function takes 3 locations, the 1st two form a line, and then it tells you how far the 3rd point is from the line that the 1st and 2nd make.

The above function finds which location along the line that the 1st and 2nd location make is nearest to the 3rd location.

function GetClosestLocation takes location A, location B, location P returns location
    local location AP = Location(GetLocationX(P) - GetLocationX(A), GetLocationY(P) - GetLocationY(A))
    local location AB = Location(GetLocationX(B)- GetLocationX(A), GetLocationY(B) - GetLocationY(A))
    local location LocReturn
    local real ab2 = (GetLocationX(AB) * GetLocationX(AB)) + (GetLocationY(AB) * GetLocationY(AB))
    local real t = ((GetLocationX(AP) * GetLocationX(AB)) + (GetLocationY(AP) * GetLocationY(AB)))/ab2
    
    if t < 0.0 then
        set t = 0.0
    elseif t > 1.0 then
        set t = 1.0
    endif
    
    call MoveLocation(AB, GetLocationX(AB) * t, GetLocationY(AB) * t)
    
    set LocReturn = Location(GetLocationX(A) + GetLocationX(AB), GetLocationY(A) + GetLocationY(AB))
    call RemoveLocation(AP)
    call RemoveLocation(AB)
    set AP = null
    set AB = null
    
    return LocReturn
endfunction 

function LineLocationDistance takes location A, location B, location P returns real
    local location ClosestPoint = GetClosestLocation(A,B,P)
    local real ReturnThis = DistanceBetweenPoints(P, ClosestPoint)
    call RemoveLocation(ClosestPoint)
    set ClosestPoint = null
    return ReturnThis
endfunction

Now this isn't the version I actually use. Because I have made a VectorLoc struct in vJass to do this. So to get rid of the leak I would change LocReturn to a global variable.

I posted it this way so they could understand my explanation.

 

[Element of Water]

Might be better (and more efficient since no GetLocationX/Y) if you make them take coordinates rather than locations, but other than that, I like it!

 

[PurplePoot]

Locations are deprecated whenever you can possibly avoid them... look into using raw coordinates.