Velocity Raptor – an adventure in 2+1 dimensions | Hacker News Reader

Velocity Raptor – an adventure in 2+1 dimensions

testtubegames.com

104 pointsstared39 comments

Hey there - game's creator here. I came across this post and figured I'd pop in to say: thanks to everyone for playing! (And thanks to stared for sharing it.)

I'm happy to answer any questions/take feedback/suggestions.

Oh, and __m: I can't reveal VR's secret identity... what if Professor Rex found out? Could spell certain disaster.

I remember playing this years ago and couldn't progress past the last few levels. Is there a cheat to skip levels or unlock them, I don't want to replay everything?

Nevermind... I just finished it.

The colors always bugged me, why does the color sometimes become black when I'm traveling towards it when it should become brighter? Perhaps because the game only simulates the frequency and we can only see a narrow spectra so it makes sense it is black on both ends.

Also the closing doors don't seem to work properly, or it is just my perception.

Oh, nicely done! You beat the game faster than I could remind myself of the cheat code!

You're absolutely right about the colors. Right now, the color-blocks only show what would happen to the wavelength (which gets 'black' as you head into UV), not the brightness. There are so many effects, which can get confusing if all presented at the same time, so I had to pick and choose which I'd represent.

That said, I really should have added levels that dealt with the brightness. It's a cool effect, too, dammit! I'll keep that in mind.

About the doors, if you're noticing what I think you're noticing, a quick explanation... Put shortly: in their rest frame, they open/shut simultaneously. But to the moving raptor, those 'simultaneous' moments happen at different times. Which is why the raptor feels like she can fit through a pair of doors that are otherwise too close together - there is a period of time (in her frame) that the doors are both open, letting her through.

I loved the game, but the constant warping of the game board meant that my eyes were a bit screwy after playing. Still fun though. :)

Oh yes, so true. I too am not immune to a bit of minor nausea after a bunch of playing. Just goes to show that our eyes & brains really aren't built for seeing the relativistic world. Not something our ancestors really needed to do :)

Could you make more levels? :)

Ha, I would love to get more time to spend working on this game. There is a level editor, though, and some players have made truly amazing levels in the game. Many are posted in the TestTubeGames forum, so I encourage you to check them out (http://testtubegames.com/forums/viewtopic.php?f=3&t=89).

One player made a quasi-"light clock" using the bullets, and another made a whole sequence of levels about the see-all seal that may as well be canon :)

Since you're using Flash, have you considered using either AGAL shaders or DisplacementMapFilter to implement relativistic aberration?

Here is a crude example I just threw together (click for focus, then use the arrow keys to move): http://circlepush.com/raptor.html

Oh, that's really cool. No, I'd not heard of those shaders or DisplacementMapFilter - but it sure looks like they could do what I need. My current method (as you can perhaps tell) is to split the (non-relativistic) image into a bunch of thin triangle fanning out radially from your character, then redraw those images onto triangles with modified angle/vertices.

It works pretty well, but I imagine using one of the methods you listed would be a lot faster. Thanks for sharing them, I'll keep them in mind for a possible upgrade to the game.

I'm a bit embarrassed to admit I didn't realize you'd already solved this, because I hadn't played all the way until level 25 the first time around. Your method looks fantastic.

Oh - haha - no problem. One of my favorite parts of watching people who know about relativity play this game is seeing them a) think of an effect that isn't shown in the game, and state that out loud, then b) reach the level that the effect is introduced. (Doppler shift, aberration, etc.) Makes me smile every time.

Have you considered using Haxe [0] / OpenFL [1] considering that flash is less and less available platform?

[0] http://haxe.org/ [1] http://www.openfl.org/

Since Velocity Raptor, I've started making my new games using Unity. That lets me release to the web (now, recently, without needing any plugin at all) or various devices.

I don't have any immediate plans to port Velocity Raptor over, though. It would take an entire rebuild of the game.

For another game on special relativity, there is A Slower Speed of Light (http://gamelab.mit.edu/games/a-slower-speed-of-light/), which is (also) very realistic: http://physics.stackexchange.com/questions/43695/how-realist....

And a list of such science-based games, which I am constantly expanding: https://hackpad.com/Science-based-games-J0X4MSberlM

whether considered a game could be debatable..

this cern based incremental game is wondrously full of great research that the player discovers through perseverance :

http://particle-clicker.web.cern.ch/particle-clicker/

Nice game. I think lots of concepts can be taught with these types of games. A physics quibble - should the raptor be able to stop instantaneously, even when moving right near the speed of light? Shouldn't slowing down happen over time just like speeding up? I'm asking both from a newtonian physics perspective and as a way of showing how time changes during the deceleration.

Thanks for playing. It's an interesting question about the huge-and-instantaneous acceleration when the raptor stops. The way I treated it when making the game was that the spacebar is equivalent to applying an acceleration exactly equal to (minus) your speed divided by the timestep of the game. Which means from one frame to the next you'll go from moving to stopped.

So from a technical perspective, the acceleration isn't infinite, since it happens over the course of a single frame. Of course, that reveals one of the odd parts about having discrete time-steps (frame, frame, frame) instead of continuous time.

Practically, the acceleration it would take to stop you that suddenly would indeed be immense, and certainly the forces would be enough to tear a normal velociraptor's claws right off her feet. (Luckily, VR is no normal raptor)

If you do want to be able to see the acceleration, you can always use the arrow keys to slow down... or hold down an arrow key as you hit the spacebar (that decreases the 'braking' acceleration)

I-is that one of KSP's space music I'm hearing on the first level ?

Yes it is. It's 'Bathed in the Light' by Kevin McLeod. He's got a nice site (incompetech.com) filled with royalty free music. Great for low-budget game devs like myself. Sounds like KSP picked one of the same songs I did.

Thanks for the link! That's going in my bookmarks.

Great game, by the way.

Thanks! And no problem about the link. I'll warn you, though, once you listen to his music, you'll start to hear it everywhere in games. So listen at your own peril :)

The Kerbal Space Program music is a little distracting, but it's a pretty clever game!

I love the game but I don't understand the exact mechanics for when I unlock a gate. Do I just need to be near the key when it is the right colour? Because that doesn't seem to work all the time.

I believe you need all the keys to turn the same color as the gate, simultaneously.

Thank you! Your method works.

With it I beat the game. The game really helped my understand special relativity in a "intuitive" way.

I've measured the bullet speed by syncing the raptor with the bullets and it seems that Newtonian bullets go 2 mph and relativistic ones (level 35) only 1.4 mph?

Different cannons shoot bullets at different speeds. Check out the (bonus) level 40 to just play around with a few different cannons at once, and see that their speeds stay constant whichever view you select.

I wanted to let the bullets have different speeds to change the 'strength' of the relativistic effects. For example, making the ones in level 9 move really, really fast so you couldn't pass through them without using a little relativistic trick.

anyone else have to stop playing due to motion sickness? it's odd; i usually don't get that from games but this one made me feel distinctly queasy.

Is the name of the Velocity Raptor Mr. Tompkins?

As in "Mr. Tompkins in Wonderland"?

indeed, the game reminded me of it. Thinking again about it, the player could also be called Mr.Tompkins.

I can't get past level 12, because I can't pick up the key although it's correct color.

You don't need to pick up the key, you just need to observe it as the correct color.

I'm pretty sure I picked it up in the previous level. How do I 'observe' it?

Edit: Seems I need to match the colors. Didn't read instructions.

I'm curious, why a raptor?

Either:

a) Raptors are the cleverest of animals, with an uncanny ability to understand relativity. b) I am obsessed with Jurassic Park and couldn't pass up a good pun.

So, you know. One of those two.

https://xkcd.com/135/

This is quite great!

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