force-dropping a cube
Also, I had this in an other thread, but it kind of got overlooked:
"The white parts of some overlays become black if I put them on a darker surface. (For example the bullseye, or the "test subject waiting area" text) Is this fixable?"
Lol, I'm learning a lot just by reading your suggestions! Thanks mate! 
So, on the topic, your suggestion would be to surround the cube with a parented trigger brush filtered by that (awesome, btw)filter and to fire the output TestActivator whenever we need the player to drop the cube plus using "OnPass" into the cube's outputs and.......... what then? what output should we fire to the cube? I mean, this far, all we can do is detecting if we player holds the cube or not, but how to make him drop it? If we fire USE output it might do nothing...
Could a basic script do this though? I mean: we can detect the cube coordinates, also the player's coordinates and set the cube's coordinates a bit further from the player's coordinates, right? how about this suggestion?
The easiest way (with a simple script) might be something like this: when the cube needs to be dropped, have the script iterate through all prop_weighted_cubes (not hard) and, for each one, send a TestActivator input to the filter with that cube as the activator (also not hard). Give the filter one output: OnPass !activator Use.
Then when the loop finds that, in fact, the player is holding one of the cubes, the filter will pass and send the Use input to that cube. Since we know that cube is held, Use will drop it.
(If this is for single-player we can also terminate the loop when that happens, although the delay required in the script might cancel out the efficiency gain.)
http://www.youtube.com/watch?v=aahkJhZZ9GQ
In this video I had a simple trigger with the "cubename Use" output, without any filters and with 0 reset time.
But even when I was careful not to get spam-attacked by the trigger (ie. increased the reset time), the cube didn't do anything. It made a sound, but it remained in my hand. Shouldn't use drop it? Or did I misunderstand something? headscratching
lord_blex wrote:
http://www.youtube.com/watch?v=aahkJhZZ9GQ
In this video I had a simple trigger with the "cubename Use" output, without any filters and with 0 reset time.
But even when I was careful not to get spam-attacked by the trigger (ie. increased the reset time), the cube didn't do anything. It made a sound, but it remained in my hand. Shouldn't use drop it? Or did I misunderstand something? headscratching
HAHAHAHAHAHAHAHA... 
FelixGriffin wrote:
Try +use;-use in the console?
That does work, thanks. But I can't wrap my head around how filter_player_held actually works. I mean I thought using filters was pretty straight forward, but this doesn't have any properties..
EDIT: Okay, I realized this thread has a 2nd and 3rd post; I may be starting to piece it together 
EDIT: Okay, never mind, I still don't get it
Note that if you fire the console command +Use, the player will no longer be able to use the USE button again, unless you fire -Use...
One, that something is wrong. I straight up copied your vmf into mine and it didn't work at all. The bsp you uploaded works just fine. 0.o
Two, I can't map. A little test map you made looks more interesting than my whole map
(Though it might helps a bit that yours has some lighting.)
If you can reproduce the failure in a small map, you could post it here so we can help you out finding the issue 
... Have you tried using the entity point_broadcastclientcommand * instead of the point_clientcommand* to execute the command +Use/-Use?
I actually had a solution with a second trigger for the player that would start disabled and enable every time the cube triggers its own trigger. Then the player's trigger can have the necessary outputs. It didn't seem too elegant, but it could work.
I certainly can't use team filters. I don't know if you remember this thread, but we are still talking about (more or less) the same 4-player map, so I can't be sure about player colors.