A different reference frame

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Rews
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Joined: Fri Apr 28, 2023 4:32 pm

A different reference frame

Post by Rews »

Hello M. TestTube!

Loved the game. Used it as a lab for my General Physics students - with excellent results.

Would love to see a new mode that allows us to play in the reference frame of the room - like if we are a person sitting in the room and V'Rap is a radio controlled toy we can move around the room. This would actually be an easier mode graphically since the room will be fixed but the V'Rap would contract/dilate. We as observer could be at top center of room looking down, or at the side of the room...

Some effects to explore:
- run fast enough to make V'Rap thinner to fit between closely spaced bullets...
- carry a bomb with a short fuse fast enough to douse it in water before it explodes... (just like the current snow and flame levels)
- doppler shift V'Rap to be "invisible" in various colored parts of the room...
- in "Seen" mode, V'Rap would run into walls that are far away from us before we see it happen - ouch!
- timing V'Raps motion through distant doors in "seen" mode would also pose a challenge
- in a new "true communication" mode, our radio control signal takes time to get to V'Rap, so our "commands" don't take immediate effect
- "true communication" plus "seen" mode should be nightmarish unless you just take slow baby steps!

Thanks for the new lab!

Dr A.
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testtubegames
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Re: A different reference frame

Post by testtubegames »

Oh yes! I love these ideas.

I prototyped a similar feature a little while back. I have visions of eventually releasing a sequel with a whole bunch more interesting things (like freely moving objects, and photons, and even light clocks).

This note certainly spurs me onward to get that all back on my list.
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Does this look a bit like what you had in mind? In this case, the camera is a stand-in for the observer watching Velocity Raptor... I was thinking the simplest thing to do would be have a replay option for levels. But I can certainly see adding in some remote-control options, taking all the communication delays into account.
Rews
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Joined: Fri Apr 28, 2023 4:32 pm

Re: A different reference frame

Post by Rews »

Yep, that's exactly what I envisioned. When I was thinking though the details, I figured it would be almost a bit boring at first - moving a sprite in a fixed room with the sprite shape changing - even simpler than the current beginning levels. But it will emphasize the main idea of different reference frames.

With some of the other features added in, it should also pose a fun challenge.

A few additional thoughts:
1) For some levels, making the hit-detection circle larger might emphasize the length contraction and allow for some fun interactions.
2) I hadn't thought of this before, but if V'Rap could shoot bullets (and/or had laser eyes!) then you could explore velocity addition effects also.
3) I don't know what you are currently doing for V'Rap's "acceleration" - a classical linear change in velocity, or proportional to a time-derivative of relativistic momentum - nor do I know if the difference would be noticeable to the player - but instead of an arbitrary "top speed", if you did use relativistic momentum then it would have a natural top speed of c - which would be approached slower and slower.

Fun thoughts all around!
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testtubegames
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Re: A different reference frame

Post by testtubegames »

That's excellent!

Yeah, I did some work on the special relativistic engine a couple years back -- and while I wasn't able to make a *full* VR2 at the time, I did release a piece of it as Veloc't in Space (https://testtubegames.com/veloctinspace.html).

In that one I did add in that feature you mentioned - where you have no real top speed. Took a bit to avoid various floating point errors, but yeah, you can run around the universe at arbitrary speeds. It'd be nice to get that flexibility into Velocity Raptor.

Thanks for the thoughts - they're making me look forward to getting back to work on VR2!
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