KSP demake

[Tom Hargreaves]

I like Kerbal Space Program, but it has its share of problems.
It's not Free, or even free. And it's kinda resource intensive.

So I'm trying to make a minimalist version. I believe the accepted
terminology for this kind of stripped-down-to-the-bare-essentials
reimplementation is "demake".

The plan:
* A 2D solar system. Planets are circles.
* Patched conics orbital simulation.
* Ships are point masses with no physics, but ship rotation,
centre-of-mass-versus centre-of-thrust, atmospheric drag,
fins and landing legs should be doable.
* Initial target is web browser with canvas, but I would ultimately
like a port to my favourite 8-bit platform, the BBC micro[1].
* The name of the game is _Little Green Men_.

What needs doing:
* Real-time simulation. Polar coordinates may be the way forward
here.
* Fast-forwardable simulation. AFAICT the best way to do this is by
solving Kepler's equation.
* Map screen. I've been implementing a Bresenham-type algorithm for
rendering arbitrary conics from
http://www.scism.lsbu.ac.uk/vgru/ManosPhDthesis.pdf .
* Sphere of influence.
* Checking the maths very carefully on all the above. I am not an
expert on orbital mechanics, but it can't be rocket science, right?
Oh, wait...
* Design a solar system. I'd like a green-themed homeworld (I
considered calling it "Forest" a la LeGuin), the rest is up for grabs.
* Ship builder. Balancing.
* Pixel art for ship components (capsule, tanks, engines, ...). Ship is
always pointing straight up and the world rotates around it.
* Flight control graphics (nav"ball", altimeter, ...).
* Any other graphics. Title screen.
* Music. In KSP, when you make it into SPACE! nice music plays.
Here the music will be https://sphere.chronosempire.org.uk/~HEx/mpjs/#mods/newmods/hyper12.xm .
I have about 90% of a Beeb playroutine written. (I know, doing such
a non-essential part first shows misplaced priorities but I couldn't
resist.)

Out at least for now:
* Multiple objects. You detach a stage, it's gone.
=> One mission at a time. No docking.
* Any actual aerodynamics. No planes.
* EVA.

As usual, the limiting factor in any of this taking shape will be
enthusiasm. So while I'd much appreciate help in actually writing it,
equally as important is people to talk to and persuade me that writing
it is worthwhile ("enthusiasm sources").

Who's in?

Tom.

[1] Thirty-two kilobytes of RAM? It was enough to go to the moon, it
was enough for you! https://www.youtube.com/watch?v=d85p7JZXNy8

[Stanto]

Awesome, I wondered why you were playing with the BBC

[Tom Hargreaves]

On Thu, May 21, 2015 at 04:25:19AM -0700, Stanto wrote:
> Awesome, I wondered why you were playing with the BBC

This is not the reason I've been playing with the Beeb. Firstly, I'm
a fair way from having anything space-related running on it (the KSP
idea only occurred to me a couple of weeks ago), and even if I had,
running space simulation code on real hardware probably wouldn't teach
me much that couldn't be discovered much more straightforwardly in a
emulator.

Instead, my initial toyage was related to
http://linusakesson.net/software/zeugma/ . I haven't attempted to run
my semi-working port on real hardware (it really, really, needs a disc
drive[1]). Instead I got distracted trying to write a font renderer
(text adventures are no good without proper (read: proportional)
fonts, right?), and then I got curious whether interlacing would
provide any resolution improvement on a vintage CRT (answer: no), and
then after seeing the huge borders I started fiddling about with
overscan for increased resolution, and then I learned how wacky
hardware scrolling is on the Beeb and took a week-long detour into
6845 hacking.

None of which bodes well for actually getting any of this finished. But
I haven't given up hope yet.

Tom.

[1] Although apparently it's straightforward to hook up random PC 3.5"
floppy drives. Maybe I'll give this a go sometime.

[Tom Hargreaves]

On Wed, May 20, 2015 at 05:37:47AM +0100, Tom Hargreaves wrote:
> I like Kerbal Space Program, but it has its share of problems.
> It's not Free, or even free. And it's kinda resource intensive.
>
> So I'm trying to make a minimalist version. I believe the accepted
> terminology for this kind of stripped-down-to-the-bare-essentials
> reimplementation is "demake".

So progress has been made! Me and some minions I acquired along the
way put together something playable[1] in 24 hours at LeedsHack.
(What, you weren't at LeedsHack? Shame on you!)

Find it here: https://github.com/hexwab/leedshack-ksp

Tom.

[1] Ish.