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Velocity Raptor – an adventure in 2+1 dimensions

testtubegames.com

21–30 of 41 posts

Re: Velocity Raptor – an adventure in 2+1 dimensions

#21
post #10

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/

Re: Velocity Raptor – an adventure in 2+1 dimensions

#22
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.

Re: Velocity Raptor – an adventure in 2+1 dimensions

#23
post #22

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)

Re: Velocity Raptor – an adventure in 2+1 dimensions

#24

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 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 :)

Re: Velocity Raptor – an adventure in 2+1 dimensions

#25

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.

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 :)

Re: Velocity Raptor – an adventure in 2+1 dimensions

#26
post #19

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.

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.

Re: Velocity Raptor – an adventure in 2+1 dimensions

#30
post #29
post #28

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.

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