Need help to understand how to make trigger_lookat working and what things i can do with it!?

I have seen a few pages explaining how the trigger works and it only writes trigger_lookat (activates when the player looks at it)
so i tried making one to test how it works, and made a iprintlnbold in script to show me a msg, but it didn't work!
Also tried to show and hide an object, or move it, no success!

Now i need someone to explain to me how it works, and do i need to add maybe something to the script for it to work!?
Thanks for any help!

Here is an example:

look_at_me()
{
MyTrigger = getent("trigger_lookat","targetname"); //Define the trigger
MyTrigger waittill("trigger"); // Turn on the trigger
iprintln("TRIGGER LOOKED AT"); // Code to run when player looks at trigger
}

Doesn't work for me!
I tried that already, and now again, still nothing!

Any other ideas?

Everything I do with look_at trigger works for me.
You could try it this way.

look_at_actor()
{
actor = getent("price","targetname");
actor waittill_player_lookat();
iprintln("YOU SEE PRICE");
}

Maybe it only works in singleplayer?

@MODDER BC, i get script error with thatone, unknown function waittill_player_lookat();

@3st0nian, maybe it is, but i didn't see anywhere that someone wrote it's singleplayer only!

I found this now on Zeroy's script (player - islookingat)
level.player islookingat( trigger );
It doesn't say it's singleplayer only.

ZeRoY's Script

Maybe that will solve my problem, but I don't know how to make a script with it. Can you help?!

It is Single Player only. For multiplayer your limited to the utility.gsc found in raw/maps/mp
waittill_player_lookat(); is a SP function.

Oh yes, i see that now!
Thank you MODDER_BC

Should be able to achieve this with some vector math:

vec1 = AnglesToForward( player GetPlayerAngles() );
vec2 = VectorNormalize( look_at_origin - player.origin );

if( VectorDot( vec1, vec2 ) > .996 )
{
	// Player is looking at
}