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Comment on A time-travelling door bug in Half Life 2

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The door and the guard are both physical objects, both have momentum, they impart an impulse on each other

I wonder if the term "impulse" here has any connection to the various impulse commands available in the source engine. I remember using "impulse 101" and causing havok in the opening plaza area. Spawning zombies on the roofs, sending them after the combine, etc.

https://developer.valvesoftware.com/wiki/Impulse

The impulse console command originates from Quake, the Half-Life 1 engine (GoldSrc[0]), was based on the Quake engine, and the Half-Life 2 engine (Source), was based on GoldSrc.

In quake, the impulse commands were used mostly to switch weapons[1]. I'm not really sure about the naming though, why choose the word "impulse".

[0]: https://en.wikipedia.org/wiki/GoldSrc.

[1]: https://github.com/id-Software/Quake/blob/0023db327bc1db0006...

Noclip FTW

Right, I was just wondering if the developers repurposed the term impulse from the physics engine when creating console commands. "impulse 101" is a common cheat to give all weapons with ammo, but why not "give" or "player.addItem" or something? Just a curiosity.

As for the name "impulse", I don't know - but the way this command works reminds me of interrupts.

The impulse command sends a command to the server instantly, rather than in the usual UserCmd sent to the server 30 times per second. They are used mostly for debugging, just assign #90 to your debugging function, then poke it from the console while the game is running. No need to change and potentially break the network code.

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