How do you use FindEntities?

[SenL]

I can't find anywhere how to use TheSim:FindEntities()

Example on staff.lua

local ents = TheSim:FindEntities(pt.x,pt.y,pt.z, 9000, {"telebase"})

 

Parameters:

1st, 2nd 3rd = initial position

4th = distance?

5th = prefab names?

 

Thanks.

[Kzisor]

@SenL, TheSim:FindEntities(x, y, z, radius, musttags, canttags, mustoneoftags)

 

 

[SenL]

Thanks, but how did you find out?

[Kzisor]

@SenL, I searched for TheSim:FindEntities 

[SenL]

I did too but found examples instead of function definition.

I also searched for "function FindEntities" but got no hits.

I use notepad++.

[rezecib]

@SenL, TheSim is a C++ object, so you won't find its function definitions directly in the Lua code.

 

But the useful code is found in scripts/simutil.lua:

function FindEntity(inst, radius, fn, musttags, canttags, mustoneoftags)    if inst ~= nil and inst:IsValid() then        local x, y, z = inst.Transform:GetWorldPosition()        --print("FIND", inst, radius, musttags and #musttags or 0, canttags and #canttags or 0, mustoneoftags and #mustoneoftags or 0)        local ents = TheSim:FindEntities(x, y, z, radius, musttags, canttags, mustoneoftags) -- or we could include a flag to the search?        for i, v in ipairs(ents) do            if v ~= inst and v.entity:IsVisible() and (fn == nil or fn(v, inst)) then                return v            end        end    endend

Which I found after ~20s of looking through results from find-in-files for "TheSim:FindEntities"

[SenL]

What's difference between that and FindEntity()

 

In abigail lua retarget fn:

return FindEntity(inst, 20, function(guy)

        return inst._playerlink ~= nil

            and inst.components.combat:CanTarget(guy)

            and (guy.components.combat.target == inst._playerlink or

                inst._playerlink.components.combat.target == guy)

    end)

 

Edit:

Oh, duh .. FindEntity calls TheSim:FindEntities .... nevermind.

Edited March 28, 2015 by SenL

[Maris]

musttags - array of tags. All tags are required.

canttags - array of tags. All tags are forbidden.

mustoneoftags - array of tags. Only one of these tags is needed.

 

For example, if an object has all musttags tags and one of cantstags, it can't be found.

If an object has only few of musttags tags, it can't be found.

etc

 

Be careful with this function. It can eat huge amount of CPU. Depends on radius.

​For example, FindEntities(x,y,z,9000) takes a few seconds.

 

 

​ 

[SenL]

Thanks!

I ended up using this:

for _, v in pairs(AllPlayers) do

 

Does that use a lot of CPU?

[Maris]

for _, v in pairs(AllPlayers) do

This is much better for finding (nearest) players. It uses not so lot of CPU. However it depends on how often you use it.

[rezecib]

@SenL, Yes, if you have a list of the entities that you're checking for, then definitely use that. Especially players, since there are so few of them compared to other entities. Depending on how clever the underlying implementation of FindEntities is (we can't easily tell because it's in the C++ code), it either has to cycle through all entities in the world, calculating a distance, or it has to cycle through all entities with the specified tag, calculating distance. So it's to be avoided whenever possible.

Edited April 3, 2015 by rezecib

[Maris]

it either has to cycle through all entities in the world

I'm not sure. Seems it depends on radius. I hope it checks sectors of the world. I would have optimized such way, if I was a C++ programmer.