On Orbits & Sun Distance

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On Orbits & Sun Distance

Post by Redspear » Sun May 12, 2019 8:06 pm

Orbits aren't in the standard game so this may be of more relevance with regards to oxps. Hopefully someone finds it to be food for thought...

Orbits are cool, right?
Dynamic systems that don't look the same every time you enter them. Great.

One problem however is that whilst they often look different they don't always look good.
Throw in the fact that you'll likely need a greater than normal sun distance and things can get rather dark and obscured.

Consider the witch point placement in each of the three hypothetical scenarios below.

Left Diagram: Orbital Mechanics

On the left we have the main planet orbiting the sun, destined to pass between it and the witchpoint (black dot). When that happens the planet will not only look distinctly plain (no visible surface details) but will also likely obscure the star (further highlighting scale issues) and making fuel scooping even more unlikely/impractical.

Middle Diagram: Spacelane Triangle

In the centre we have the classic Oolite static triangle. Result is a reliably well lit planet and reasonable fuel scooping practicality. Note that if the triangle is non-equilateral and the sun is closer then lighting remains good, once the sun is further away then the main planet is increasingly obscured; fuel scooping is also more rewarding when you don't have to travel so far. Drawbacks here are that the closer sun highlights scale issues and once you introduce orbits then all the benefits are lost.

Image

Right Diagram: Hypothetical Conjunction

Rightmost of our hypotheticals has the witchpoint placed between the sun and the main planet. In some ways this is the most logical place to put a witchpoint, between the two most typical system destinations. Great lighting, fuel scoooping is good, and you will almost never have both the planet and the sun/star in your field of view at the same time - in fact the distance here is the most efficient use of space given that the wichpoint is the centre of the system. Visually a bit boring however and if you want orbits then the whole thing falls apart unless they both orbit the wichpoint but then that's a bit odd...

So, can we still have orbital mechanics and have something like the last scenario?
Well, suppose orbits only applied to other, added planets or moons - as if the witchpoint orbited so that it was always between the sun and the main planet. You could then see orbiting bodies but the main planet would almost always be well lit and highly visible. This is especially relevant when the distances used are greater than normal (and for orbits they likely should be!).

In other words, the diagram on the right would remain static, with other bodies orbiting either the sun (added planets) or one of the planets (moons).

Even without orbis it could be good if the witchpoint were closer to the star than the main planet. Fuel scooping is often a waste of time, or at least is more of a spectacle/experience than it is a practical strategy. With a closer star however, it could be a very wise decision if you've just made a large jump into a dangerous system.

I still think it would be good to have at least some distance between witchpoint and star however an account of at least three things:
  • Solar glare
  • Fuel scooping should be a choice rather than a 'no-brainer' IMHO
  • Closer star means either it is also closer to the main planet or that the witchpoint must be further from the planet
If a system is to be populated with more than one planet then I think this might be the best way to make it work (or at least the best way I can think of). Even if it remains a one planet system then I think it is the most space efficient and fuel-scoop friendly layout.

Got a better idea? Please, I'd very much like to hear it.
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Re: On Orbits & Sun Distance

Post by Disembodied » Mon May 13, 2019 1:00 pm

The witchpoint doesn't necessarily have to be in the system's plane of the ecliptic … it could be e.g. above the north or south pole of the star.

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Re: On Orbits & Sun Distance

Post by Redspear » Mon May 13, 2019 4:43 pm

True but in either of those polar configurations you'd see hemispherical planets (one half lit) and a clear overview (like looking at an orrery) of a now obviously small system with an obviously tiny star.

The arrangement wouldn't have to be polar of course but the more you leave the ecliptic the more the whole system is revealed, and the more scale issues become obvious. Of course to really notice orbits you need a compacted system anyway but the tiny sun will really show up with an 'overhead view' I think.
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Re: On Orbits & Sun Distance

Post by Rustem » Tue May 14, 2019 8:02 am

Hi!

The some 'todo' tasks, whitch need correctly setup of the system:
  • ship traffic;
    location station in near sun;
    location station in near extra planets.
Also need solved the next: How better will located other station(Rescue Stations, Seed Bars, Rock Hermits, Kiota stations and etc.)? They will spawn as:
  • station in near main planets(as moon),
    or station with independent orbits(as planets).
This thinking become after learn the Orbits OXP in the past. Also was installed the System Redux and the Stations for Extra Planets Base. I found the Orbits working incorrectly. The station is spawned in the wrong location, because the Orbits shifted the planets to a new location.

My last tweak for working correctly of the orbits. Link to folder:link.

At the moment, I was checked that the spawning of rock hermits, couriers and pirates on the wp-sun line is correctly (priority in the orbits population is 15). The second check point: the spawning of stations near the sun. Found problems with packages: Comms, WildShip and Wildship Kyota relocator.
My tweaks: for Comms, WildShip and Wildship relocator(code is draft version, can fix its). Now, they work correctly with the Orbits v1.5.0.

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Re: On Orbits & Sun Distance

Post by Rustem » Tue May 14, 2019 8:08 am

Disembodied wrote:
Mon May 13, 2019 1:00 pm
The witchpoint doesn't necessarily have to be in the system's plane of the ecliptic … it could be e.g. above the north or south pole of the star.
Agree with you, but not solved in the Orbits OXP as math task. I think about this task.

May be the witchpoint will located to near main planet almost as moon, above the north or south pole of the main planet?

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Re: On Orbits & Sun Distance

Post by Disembodied » Tue May 14, 2019 11:29 am

Redspear wrote:
Mon May 13, 2019 4:43 pm
True but in either of those polar configurations you'd see hemispherical planets (one half lit) and a clear overview (like looking at an orrery) of a now obviously small system with an obviously tiny star.

The arrangement wouldn't have to be polar of course but the more you leave the ecliptic the more the whole system is revealed, and the more scale issues become obvious. Of course to really notice orbits you need a compacted system anyway but the tiny sun will really show up with an 'overhead view' I think.
True … how about having the WP at one of the Trojan points on the main planet's orbit - i.e. roughly 60° ahead or behind? The distance from the planet to the star could be calculated by a combination of the star size and colour: assuming all habitable planets are within a roughly Earth-like Goldilocks zone, planets orbiting large, hot stars will have large orbits and planets orbiting small, cool stars will be huddled close in. As long as it's not a linear relationship, some systems will have planets (and WPs) that are close to their stars, and some will be far away. Other planets in the system, in different orbits, could still be inhabited, but in domes/other sealed habitats.

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Re: On Orbits & Sun Distance

Post by Redspear » Tue May 14, 2019 4:58 pm

Rustem wrote:
Tue May 14, 2019 8:02 am
This thinking become after learn the Orbits OXP in the past. Also was installed the System Redux and the Stations for Extra Planets Base. I found the Orbits working incorrectly. The station is spawned in the wrong location, because the Orbits shifted the planets to a new location.
Hi Rustem. I don't think that's an easy task and I admire you for taking it on.

Disembodied wrote:
Tue May 14, 2019 11:29 am
how about having the WP at one of the Trojan points on the main planet's orbit - i.e. roughly 60° ahead or behind?
I think I'm following you (witcpoint orbiting ahead or behind the planet but along the same path?) but I think distance might be the key consideration here - not just in terms of scale but particularly with regards proprtion.
  • Witchpoint to planet determines travel time and encounter rate (without tweaking a la the Rescaling Experiment)
  • Witchpoint to sun determines (in part) risk/reward ratio for sunskimming
  • Planet to sun determines apparent size/proportional realism of system

So ideally, WP-Planet is reasonable, WP-Sun is not to big and Planet-Sun is not to small

3 scenarios again...

Image

On the left: an equilateral triangle where all of the spacelanes (blue lines) are equidistant (x).
You can see most of the planet surface when entering the system (50% being the max from a solitary vantage point when looking at a spherical body) but there is still low incentive to sunskim. In fact, in all but the safest systems sunskimmimg will not only be unattracticve but also impractical - by the time you've made it to the sun, you could have made it too the station. The system is also rather cramped. It is a rare situation where the player leaves the main station to top up fuel prior to making a jump, so I don't think they need to be so close: vary rare benefit for consistent visual penalty seems a poor trade off to me.

Travel costs:
  • Straight to Planet = x
  • Sunskim to planet = x + x = 2x
In the middle: a sun distance modifier of two (2x) has been applied. Visually it's a little more realistic, although planet visibility is beginning to suffer (and will only get worse with increased distance multiplier). Sun skimming however now seems a very strange strategic choice - why travel four times the distance (with comparable increase in risk) for something you can buy for a few credits at the station. Not only that but by the time you do reach the station you may well need to top it up anyway after having likely used fuel injectors on the double length route from sun to planet.

Travel costs:
  • Straight to Planet = x
  • Sunskim to planet = 2x + 2x = 4x
On the right: the 'conjunction' I mentioned in a previous post. Visibility is great at 50%, and the sun is now more accessible at 1/2x. Planet to sun distance is not as large as in the second example and yet at the same time this is less obvious (very unlikely, even upon launching from the main station that the two will ever be in shotat the same time). Sun skimming is now much more tempting however, especially after a large jump into a dangerous system. Even if the 0.5x distance from witchpoint to sun is increased, you don't quite have to pay double the sun to planet cost as in the other examples.
e.g. suppose it were also x from witchpoint to sun, sunskim to planet would then be x + x (back to wp) + x (on to planet) = 3x.
The planet and sun would be just as far apart as in the middle example and yet instead of a 4x journey (not a XXXX journey, which could take a lot longer...) the cost would be 3x.

Travel costs:
  • Straight to Planet = x
  • Sunskim to planet = x + 2x = 3x 0.5x + 1.5x = 2x
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Re: On Orbits & Sun Distance

Post by Rustem » Tue May 14, 2019 7:27 pm

May be the witchpoint will located to near main planet almost as moon, above the north or south pole of the main planet.
Suggestion in picture:
Image

So the witchpoint always will move with main planet simultaneously.

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Re: On Orbits & Sun Distance

Post by Redspear » Tue May 14, 2019 10:41 pm

Rustem wrote:
Tue May 14, 2019 7:27 pm
May be the witchpoint will located to near main planet almost as moon
If you mean a moon with a standard space lane distance then I'd be inclined to agree.

Rustem wrote:above the north or south pole of the main planet.
Here however, I'm not convinced. For orbits to look good we'll need bigger distances and yet for orbits to be significantly noticeable for anything other than moons, we can't go anywhere near full scale.

So, there's a compromise between apparent realism and looking good. Having the witchpoint in a polar orientation to the main planet will, I suspect, further highlight to conflict of such a compromise.

Sunskimming will also likely be even less attractive a propsition if the witchpoint is much closer to the main planet than it is to the star.

Rustem wrote:So the witchpoint always will move with main planet simultaneously.
Yes, both your suggestion and mine have that in common, except that in mine the 'movement' is illusory.
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Re: On Orbits & Sun Distance

Post by Cmdr James » Thu May 16, 2019 12:34 pm

What is the canonical reason for having a witchpoint at all?

As a trader in the ooniverse I would of course want the system entry point as close to the station as possible, so I dont waste time and more importantly risk my life cruising around in deepish space for no reason. Obviously however parking the witchpoint near the station breaks the core of the game which is flying about in space. Gravity would make a decent excuse for it not being too close, perhaps?

It seems right to me that a lagrange point (some of which are called trojans in the post by disembodied) would make sense. But if we have realistic suns and planets (yes, big if) then they are all way too close to the planet.

For ingame aesthetics -- I expect a planet with partial night would be on average more interesting than always approaching from 12 noon.

For playability and fun I think the discussion is mostly not a big deal, whether I sit for 3 minutes or 5 with my finger on the j button isnt the key fact for my fun. As long as the action mostly occurs on the corridors between witchpoint and sun/planet (and maybe between sun and planet if there isnt a witchpoint between them) then Ill be happy.

Personally I think sun skimming is already broken, there is no way to make it a sane choice for a trader without major game changes, either limiting fuel for sale, changing fuel needs (hugely) for different ship sizes or maybe something else, but its not made better or worse by moving the withpoint about a bit.

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Re: On Orbits & Sun Distance

Post by Redspear » Thu May 16, 2019 8:05 pm

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
What is the canonical reason for having a witchpoint at all?
Strictly speaking, I don't recall there being one.

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
Obviously however parking the witchpoint near the station breaks the core of the game which is flying about in space
Yes, so it's what makes a good game over what is the most trader friendly.

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
For ingame aesthetics -- I expect a planet with partial night would be on average more interesting than always approaching from 12 noon.
Given a small variance (and/or a very large percentage of 'day'), I'd agree. Otherwise I feel it would draw further attention to the fact that it is always the same.
How so? I think the brain is drawn to fill in the missing part of the sphere and so notices its partial absence mre than it does its entire presence... but this really is a minor point.

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
whether I sit for 3 minutes or 5 with my finger on the j button isnt the key fact for my fun.
It might be if number of encouters are affected...
As a qualifier here, I am much more aware of what happens when making the distance between WP and planet larger than I am when doing the same to the sun distance multiplier. In the case of the former, encounter rates are increased (should the width of the spacelane remain unchanged). If that were also be the case for increasing WP to sun distance then it is no longer purely about time but also about risk.

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
Personally I think sun skimming is already broken
Agreed.

Cmdr James wrote:
Thu May 16, 2019 12:34 pm
its not made better or worse by moving the withpoint about a bit
Disagreed.
Should I be wrong about encounter rates in my earlier paragraph then it would rely upon what pirates et al do upon reaching the end of the WP-Sun lane. As long as they do not simply turn around for a return journey then it could still be relevant.
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Re: On Orbits & Sun Distance

Post by Redspear » Thu May 16, 2019 8:28 pm

Speaking of encounter rates...

Supoose WP-Sun and Sun-Planet each had half the encounter rate of WP-Planet (x), regardless of the distance.

Head straight to planet: encounter rate = x
Head to sun and then on to planet: encounter rate = x/2 + x/2 = x

So sunskimming would take more time and is a little more dangerous (performing the sunskimming itself) but the player faces no more pirates/police/bounty hunters/thargoids than when headed straight to the planet from the WP.
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Re: On Orbits & Sun Distance

Post by Astrobe » Thu May 16, 2019 9:34 pm

On the viability of sun-skimming, one could make repairs and refueling at a station cost much more time (on the in-game clock). Players doing contracts could then use sun skimming as a joker when late, or as a way to run more contracts simultaneously.

I think it should be relatively fair in the base game given that traveling to the sun + sun skimming takes more (real) time. If it's not true, one can make it so that high cabin temp shortens the service time (if it isn't the case already).

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Re: On Orbits & Sun Distance

Post by Disembodied » Fri May 17, 2019 11:59 am

What if the WP was always placed on an orbit around the star, but closer in?

It would obviously be problematic if the WP and the planet ended up in opposition, with the star in between them, so perhaps the player should only ever arrive at the WP on an arc covering (say) 90° of its orbit closest to the planet.

If the placing on that arc was random, then there would be an (admittedly fairly flimsy, but hey ho) illusion of dynamic orbits, and a mixture of planetary illumination. And if planetary orbits were placed according to star size/temperature, then with cooler stars the WP could end up being closer to the star than the planet. So some systems would be better for sunskimming than others, which could help to make different systems look and feel more different from each other.

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Re: On Orbits & Sun Distance

Post by Redspear » Fri May 17, 2019 8:22 pm

Astrobe wrote:
Thu May 16, 2019 9:34 pm
On the viability of sun-skimming, one could make repairs and refueling at a station cost much more time (on the in-game clock). Players doing contracts could then use sun skimming as a joker when late, or as a way to run more contracts simultaneously.
Not sure about repairs but as for fuel that would make sense (presumably time in delivery rather than installation). Perhaps the quirium fuel is sufficiently unstable that it must be delivered and not simply piped. There is some canonical background to that interpretation but it's not exactly intuitive when you spend 30 minutes filling your tanks... I quite like the idea though as it's so simple.

Disembodied wrote:
Fri May 17, 2019 11:59 am
If the placing on that arc was random, then there would be an (admittedly fairly flimsy, but hey ho) illusion of dynamic orbits, and a mixture of planetary illumination
I've considered that before and hinted at it in one of my answers to Cmdr James and also (very much indirectly) in the orbital path on the first diagram I posted. I think it works fine until it has to change direction (or jump back to a start position). I've considered a smaller 'wobble' (which may work slightly better) but then it seems strange goint to the trouble of making other bodies take orbital paths in the first place.

This is another reason why I favour staying on the ecliptic plane as it helps disguise just how much fudging is going on.


OK, so if it's a pain to move the planetary bodies around then might it work better to move the witchpoint around instead and if so then how?
If we could go for the illusion of planetary orbits rather than actual orbits (moons are much less of a problem I think) then could that be workable?

Suppose that rather than there being only one witchpoint that there were three, or even five, and each time you jumped into a system you were randomly allocated to one of these predetermined entry points. Very much different appearances are now possible and sunskimming could be affected also - we'd only need one of the entry point to be good for fuel scooping.

Because the entry points would be predetermined options then you needn't get awkward outcomes like the planet being hidden behingd the star. Furthermore, because your vantage point has moved, it becomes less obvious that each of the other bodies hasn't (given sufficient distance from each other.

The core system coding generates the system centred around the witchpoint, so that presents an obstacle to this idea as does populating the spacelanes but it could still work if just one of the 3/5/whatever entry points remains the 'true' witchpoint. If one of the additional points was near enough to the sun then you also have the wp-planet and wp-star lanes intact. We would then potentially only need two more lanes from an additional entry point (route to star and route to planet/station). Admittedly, these additional routes would stack for each entry point beyond the third... unless the lanes themseves could be moved - a player centric solution but one that would almost always go unnoticed as such.

Could be some work but I'd love to try it out.
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