How to make a makeshift crane; or alternatively - How do I move ropes?

Heya.

I am currently working on a Payload map which includes something similar to barnblitz second, where the payload is paused for a second on the track.

However, instead of a.. spinny-thing on the ground I wanted to make a cool crane that lifts up a log that's currently on the track.

Someone suggested I should do it with ropes. Sounded good, they have an auto-resize flag, so I did the following setup:



At the top of the crane model is a keyframe rope.

In the middle, a path_track.

At the bottom in the log area, you have:
- the log model (prop_dynamic)
- a shoddy func_brush as a purely visual thing
- another keyframe_rope
- a path track, marking the beginning.
- a func_tracktrain

Putting it all together, from a purely functional perspective, everything works fine. The log is being moved upwards, ends where I want it to end and the payload is stopped, gets to move etc. when I want it to.

However - the ropes don't!


This is how it looks like in-game mid-lift - the rope does not move a single meter/inch/farenheit.

Quite frankly I have no clue why this is the case. The bottom keyframe_rope is parented to log_movement, which is the name of the path_tracktrain. The log itself and the func brush are also parented to it and move fine.

Even the wiki (https://developer.valvesoftware.com/wiki/Cables_and_Ropes) says that the auto-resize can be used to make cranes, yet here I am.

Here are the property windows for each part: Log_movement being once again the func_tracktrain, keyframe_rope_end being the *bottom* of the crane, and keyframe_rope_start being the top.


To prevent the log from going wonkers, the func_tracktrain has the "Fixed Orientation" flag.




Both log_rope_start and log_rope_end have the Auto resize flag checked.

If anyone has any experience or ideas on how to fix this, I'd greatly appreciate any input. I've been struggling with this for a while now, and I hope to find masters of ancient pseudo-crane technology here.

Thank you!

 

You gotta use move_rope instead of keyframe_rope

 

No dice

Both are move_rope, both are connected, bottom is parented to the tracktrain and both have the auto-resize flag...

Here are the rope entities in question again, now both being move_rope...

 

Not sure if this will fix your problem, but you have to make sure the first keyframe in your rope sequence is a move_rope, with all the rest being keyframe_rope. So in your case, log_rope_start would be a move_rope, and log_rope_end would be a keyframe_rope.

 

The same. It still refuses to move - or atleast auto-resize.

 

...Can also confirm that turning the flag off in the move_rope and enabling it on the keyframe only causes the same thing to happen; nothing.

 

It is NOT possible to parent a move_rope or keyframe_rope. However, there's this entity called logic_measure_movement that will allow you to apply the movement of one entity to an other (essentially mimicking parenting) and the good news is that it works with ropes.

 

I believe this example still works. This does what fubar just suggested above.

 

Thank you so much!

 

I ran into another issue. While the ropes do move, sadly now they slack. Does the auto-resize flag only have to be checked on one rope entity, rather than both?

Slack is 0 on both of them, so that can't be it. I think.

 

Well for anyone that might stumble over this in the future, setting the rope to rigid fixed the issue!