You could do that with a lua script easily enough, just like in construction mode. It would even be a fairly small lua script. Drop by irc://irc.freenode.net/hedgewars for help ( use the Live Chat link at the top of the site if you don't have an IRC client already, or try https://addons.mozilla.org/en-US/firefox/addon/chatzilla/ in which case the link above would send you straight there.

FWIW, based on IRC discussion, think we are going to let lua define girder placement distance in a configurable gear value in .22, since the approach construction mode uses is a wee bit convoluted. That is, it has to figure out that one has a girder active, keep track of user actions that change the rotation, and use that to spawn a girder sprite when targetting is triggered. Props to mikade for going to the trouble, but, yeah, a bit of a pain ☺

Update.
IMO the approach in Construction mode is not really needed.
To recapitulate comments in chat, I *think* this would work...
local myGirder
function onGearAdd(gear)
if GetGearType(gear) == gtGirder then
myGirder = gear
end
end

function onHogAttack(wep)
if wep == amGirder then
x,y = GetGearTarget(myGirder)
PlaceGirder(x, y, GetState(myGirder))
DeleteGear(myGirder)
end
end

This should probably work. Totally untested.

*edit, fixed typo*

Nemo's code almost works, but it is “GetState” instead of “GetGearState”. The basic idea of nemo is correct. I have used this skeleton to add this functionality to my Game Hacks script, but I added some tweaks.

My Game Hacks script (http://www.hedgewars.org/node/6279) now also includes a parameter where you can increase the girder placement range or disable the limit completely.

Read the code from line 1107 (in version 7).
The “lastConstruction” variable is just written to whenever a gtGirder or gtRubber is created.

However, I have run into problems with placing rubber, because the only way to place rubber with Lua is with PlaceSprite (there is no PlaceRubber), but unlike PlaceGirder, this ignores the land so it would be perfectly possible to place rubber inside land!

So I have disabled the range modifier for rubber for now.

related note:

The next version of Hedgewars (0.9.22) will have a call called SetMaxBuildDistance.

e.g. use SetMaxBuildDistance(1000) to allow placing Girder/etc. within a 1000 pixels radius of the Hedgehog.

Use SetMaxBuildDistance(0) to have no limit and allow placing anywhere.

If you want to reset the build distance to the default value, just call the function without any parameter: SetMaxBuildDistance()

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Nice!
Don't forget to update Construction Mode and HedgeEditor, respectively.

If you insist, I could do it for you.

Do we need a call like this? This sort of fine-grained thing seems like something we could simply use the Radius parameter on the gear to set.

That allows lua more flexibility no? Like expanding radius in certain circumstances or for certain crate selections or distinguishing between rubber and girder ranges.

And we already let lua mess with a bunch of gear parameters for various effects. This seems no different.

Hm, you have a point there.

Although it wouldn't allow for more flexibility (you can still do the exact thing you described either way with no additional effort).

The global way at least saves Lua from having to check ammo type on every weapon change and having to set radius each and every time something that can be built is selected.

Also scripts would have to be changed if new buildable ammo is added.

Wait wait wait wait wait... there is no gear at that point when placing... just ammo type... what radius to begin with?

If you want to check range only after - the available construction range couldn't be displayed to the player by engine.
Then even more LUA code would be necessary to do that.

  sheepluva <- me  my code stats -> 
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Radius in onGearAdd, not onHogAttack

And was mostly just that "letting lua twiddle w/ gear values" is how we normally handle messing w/ weps

Thanks guys , really thank you for everything !!
Now I can finish my degree ... as soon as I can I 'll show you some work if you like .
Anyway thanks again ... you are great