The only problem with this in terms of a game system is that you're still limited by the Speed of Light. If you're playing a game with such a drive, it would take you three real years (or perhaps half that, depending on the in-game time scale) to reach just the nearest star. Not to mention Einstein's General Relativity and the Lorentz Transformations ... I've done a little preliminary calculations about this, and to give you an idea of what the reality would be, consider this:
Let us state for the sake of argument that you are travelling at 40% the speed of light toward Betelgeuse, which is approximately 500 light years away from Earth (there is a wide margin of error here, so excuse the number). At 40% speed of light, 1250 years pass aboard your ship, and 1310 years pass back on Earth (60 year difference). My calculations are based on an old spreadsheet that went through some changes, so the exact numbers may be wrong ... I'll have to redo the formulas to insure accuracy. (In one of my calculation cells, it's telling me 505 years ship time, 3580 years Earth time, which seems a bit more accurate ... regardless of which one is correct, they both break the ability to play the game reasonably). I'm currently revising the spreadsheet in order to realistically portray the Relativity equations. The spreadsheet is eventually intended to be a resource for science fiction authors to accurately use and portray subluminal speeds and Relativistic transformations to insure accuracy.
For any game using extrasolar planets (especially at the already realistic scales Outerra uses), you have to go beyond what is actually possible in order to make it fun. Not to mention that the game will initially focus solely on Earth ... the other planet stuff will only come, if ever, when the planetary building tools are built (which is the part I'm waiting most eagerly for
*Edit* just revisited the original spreadsheet that was unaltered. Here are the corrected Relativity equations/transformations:
Betelgeuse 500LY distance 714.29 years ship time 5063.44 years Earth time
(Based on 99% speed of light velocity)
*Edit2* For clarity .. if it's still confusing, I can reply in a separate thread or through forum email. Relativity is a special interest of mine, for a variety of reasons
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