that's a nice showcase, and I agree it would be more realistic, but basically it has been talked about a lot already.
Doing this without having physical space ships for singleplayer is not that much of a problem (it has a lot of game-play implications still)
Changing context from a sphere to a block world is something that only works in theory. I've seen a lot of attempts including my own. It causes way more problems than it would solve.
- Seeing the world from 2 difference points in space would have to account for the warp in space. And you dont even have a "point" in this space. If you would put actual space ships in there their geometry would be warped in the border zone. All shots/missiles etc would warp, which means you couldn't really hit anything on a planet from space. In their case they are warping the blocks themselves, which is relatively simple with one restriction that pretty makes the concept impossible for actual gameplay: The planets have to be huge, and there cant be any serious elevation going on. The more you move to or away from the core from a certain "good" value for that sphere you are on, you will see very ugly graphical things.
- data size: as every planet is it's own world, you have to save at best case everything modified. And modification is done as easy as a few missiles. Check the starmade server database, in where planets are the biggest entities (given there is a lot of room for optimization)
- gameplay: Those worlds are huge and starmade is already huge. putting in vast areas where even mincecraft players on the same player would never meet wouldnt exactly help gameplay in my opinion.
Still this is a very cool video, but it's just not practical, especially with starmade focusing on space and less on planets
...
oh yeah, more faces would make it rounder. A complete sphere (in theory) would have infinite faces. So based on that I tried to find (based on the input of the forum) a good middle ground of where gameplay and realistic planes would be ok to meet. I mean we are always talking about making a sphere of a cube which doesn't really work in this gameplay context.
If i saw any realistic chance of doing this kind of planet, believe me, I would do it.
The problems with bigger planets are things not visible in the video. The planet, except the places that are absolutely near the player, is hidden by LoD (Level of Detail).
It is mostly used in graphics programming, but in this case has to be also used for the data, as its impossible to hold even one planet of that size - even if one block is just one bit - in memory.
As a simple example of what that means, is shooting a laser from orbit to a planet that is just made out of general very rough faces (planet surface -> very big cubes -> smaller cubes -> smaller cubes -> ...). The shot would have to resolve that to the actual smallest blocks to see where those hit. Now imagine 100/sec of those. Also you have to build a physical mesh for all of those faces to check where stuff collides, and that mesh has to be recalculated constantly for more than one player.
This isn't the first video showing something like this, and people get excited. I understand that. But a fine showcase doesn't translate into the same gameplay that you'd expect. There are a lot of little and bigger things that have to be considered