Developer Insights #21 - Rockets' Red Glare

[RocketRockington]

1 hour ago, PDCWolf said:

Yes, put hot part in cold water, it cools, I get that. Nowhere does it say that the actual size/contact area of the part will affect that beyond an arbitrarily defined number (to make it clear: grab big wide part, submerge only a smidge of a corner in water, the whole part acts like being underwater).

Another fun thing I'm thinking about is exploiting shade by mounting radiators on movable surfaces or just planting a part on top of them to make shade, since the only heat transfer is to the environment, which apparently will be infinitely efficient (and thus no part-environment-part radiation)

 

Yeah it seems extremely unlikely, given how much they're dumbing down every other aspect of heat, that they'll calculate wetted surface.  Or really any aspect of surface area.  Spherical cows and whatnot.   

Tbh though 'shade' is mentioned once, briefly, Chris also talks a lot about making it super easy to calculate the state of a craft's thermals at high warp - and shadows, especially from other parts are not easy to calculate or update at all when you have a colony rotating under the sun - certainly much harder to calculate than something like part-to-part heat flux which they've already thrown away.

My guess is that was a throwaway phrase and actually the only shading calculation will treat planets as perfect spheres and have no part shadowing whatsoever, but that's just because my experience of KSP2 has been that they deliver less than even the pessimistic/realistic people like yourself expect.

Edited July 22, 2023 by RocketRockington

[Book]

6 hours ago, Nertea said:

  An overall question I'd like to answer is whether you feel like this dev blog was a useful thing for me to put together. Given that my role on the KSP2 team is as a designer, I'm limited in what I can write about, and thought I'd try a long-form design document. If it was informative and interesting to read, I've accomplished my goal, but it is quite a time sink to write long things.

 

It was a very interesting read, thanks for putting this together. I was definitely in the camp of "where reentry" before, but now it totally makes sense, you just casually comitted to remaking it all from the ground up, design it so that it makes for interesting probelms, balance that so that the problems actually are problems, and somehow find a way to display all that information in an easily digestable format in the VAB, while still handling the many different use cases in advance.

Yeah, no kidding that's taking time, but it sounds like it's going to be a really good addition to the game.

[Vanamonde]

All the posts not talking about the heat system have been moved to the Grand Discussion thread. 

[Gotmachine]

So, if I understand correctly, this is a stateless system where only instantaneous heat fluxes are considered each tick, with part temperature being an analytical result of the current fluxes, with no concept of stored energy ?

Edited July 22, 2023 by Gotmachine

[Periple]

59 minutes ago, Gotmachine said:

So, if I understand correctly, this is a stateless system where only instantaneous heat fluxes are considered each tick, with part temperature being an analytical result of the current fluxes, with no concept of stored energy ?

That’s not how I read it. If I understood it correctly, part temperatures are still tracked with fluxes determining whether they cool down or heat up, however conductivity between parts isn’t modeled. At very high warp levels or for unfocused vessels you can compute the equilibrium pretty cheaply because you’re not considering part interactions, only the fluxes, and can determine if any given part reaches equilibrium below its threshold (all good) or not (kaboom).

I.e. the only simplification over KSP1 is that parts no longer transfer heat between each other, and according to Nertea the practical gameplay impact is minor while it has big computational advantages. It’s a lot like the drag cube/occlusion based approach to aerodynamics really.

This tracks for me intuitively; I can’t really think of any situation where heat transfer between parts was a major problem or benefit for re-entry or atmospheric flight — the challenge always was to shield the delicate bits or come in gently enough to be survivable or to design a craft that was robust and draggy enough to survive Eve. The only time I had to consider parts as heat sinks was to manage ISRUs and drills which use a totally different thermal model.

[Gotmachine]

3 minutes ago, Periple said:

That’s not how I read it.

TBH, I have no idea how to read this, that's why I'm asking. This is talking a lot about goals, and is very vague about what the actual system will be.

[Periple]

2 minutes ago, Gotmachine said:

TBH, I have no idea how to read this, that's why I'm asking. This is talking a lot about goals, and is very vague about what the actual system will be.

Oh? I thought it was very clear!

[KUAR]

11 hours ago, Nertea said:

  An overall question I'd like to answer is whether you feel like this dev blog was a useful thing for me to put together. Given that my role on the KSP2 team is as a designer, I'm limited in what I can write about, and thought I'd try a long-form design document. If it was informative and interesting to read, I've accomplished my goal, but it is quite a time sink to write long things. 

Well, I believe the devlog is pretty clear about allocating the radiator stuff for release around the Colonies update there  . 

These are EXACTLY the stories I am excited about with this system. Reentry can be an interesting challenge, but ultimately it gets solved the same way every time - you use a heat shield or you keep your speed low - hard IRL, trivial in KSP. When you get that complex environmental context going, you start to have more options and trades to make about where you site something. 

Ultimately I'd eventually like thermals to be as varied as engines in terms of problems to overcome. Just like engines have different situational uses and different requirements around sizes and fuel types, different cooling methods and approaches should be valid in different situations. 

I'd place that in the 'computationally complex and challenging to make performant' category. 

Fair. And I'd take the simpler system any day, if it will be computationally more efficient - I'm sure we can agree that performance is something we need to be cognizant of. 

I would generally argue that heat in KSP1 has no practical utility outside of reentry and stars, because it vanishes when a vessel isn't focused, and reverts to analytic mode when you're over 1000x warp anyways, which disables conduction and replaces it with an approximation. The system is tuned so that the only time a player needs to interact with it is during reentry and atmospheric flight, which it succeeds very well at (this ignores the core heat system that runs drills and such which is completely different). I'd like to do better than that. 

I doubt we'll convince each other here, but I hope we can demonstrate that as we deliver the system over the next few milestones that it makes for interesting gameplay. 

 

Chris, thanks for an informative and interesting Dev Blog.

I'll be honest, my initial reaction was "sounds like an oversimplification" but having considered it a bit more I think you're on the right track.

Some people are complaining that by not modelling internal conduction you're allowing designs that weren't possible before. However genuine systems would always be able to factor in active cooling to radiator panels, so I think that's OK. In fact KSP1 had just such a system which led to the same results with a far higher calculation overhead. 

I think that perhaps, with some refining of parts' thermal generation and emission rates in different scenarios (sunlight/shade/atmosphere/vacuum) it is a pretty solid basis. People harp on about realism but wouldn't recognise it if it slapped them in the face - KSP1 heat model was far from realistic in some ways and people were quite happy to learn the rules of the game in those cases. If they want more details, then they can wait for modders to get their hands on it.

As for was the blog worth the man-hours and the subsequent grief from committnegatives, I think that for your own sanity though sadly perhaps the time is better invested in developing. 

[PDCWolf]

12 hours ago, Strawberry said:

snip

Excuse the quote, but I want to follow up with a better explanation now that I had my sleep, as I think I can make myself much clearer in what I was trying to achieve, now. What I understand from the system is the following (prepare your brain for very advanced stuff):

 

[Stephensan]

1 hour ago, PDCWolf said:

Excuse the quote, but I want to follow up with a better explanation now that I had my sleep, as I think I can make myself much clearer in what I was trying to achieve, now. What I understand from the system is the following (prepare your brain for very advanced stuff):

 

hope we can do long distance systems with "pump boosters" stations etc for cooling that is FAR away.

 

i wonder if there will be power lines, either just the big fat ones that "scurry" on the ground or like a traditional ones that are lifted in the air?

i hope its both, both is cool

[Geredis]

Lovely little diary. I've quite enjoyed it. However one thing I see that was rather omitted was thermal shock - that is consequences for wild (and especially repeated) swings in temperature.

Let's say we have a small capsule with heatshield coming in to land in an icy sea. It's been heated to ridiculous degrees on the way down. The heatshield has protected the craft thus far. However, upon landing, the stored heat in the heatshield is then sucked away by the ocean at an incredible rate, such that the part cools down near instantly.

In this situation, is it possible for the thermal emission, and the associated implied part contraction after severe thermal expansion experienced, in this case, by the heatshield, to be sufficient to break the heatshield? I'd love if the game required that kind of awareness and planning for landing sites, where you might want/need a slow and steady radiation of reentry heat in order to ensure a part remains viable/useful for re-use.

As it stands from what I've seen in this, it does not appear that this kind of a situation is being considered, which is a disappointment of sorts, since it does not seem to consider thermal shock to be something to be considered. Instead, it seems as if, if you desired, that you could heat up a craft to 95% of its breaking point, with a whole mess of deactivated radiators stuck on it. Then deploy them all, and provided you have enough radiators, you could theoretically dump all of the ship's heat in 1-2 seconds to use a bit of an extreme example.

Such a violent and sudden transfer of heat should have consequences, and it does not appear to.

[Scarecrow71]

10 hours ago, Pthigrivi said:

It may be that at a certain point of expansion you might want or need to set up outposts to gather new materials or take advantage of better access to energy or heat dissipation. That only sounds like a good thing to me. As for parts the idea is if you can gather or deliver resources to a colony you can build components right onsite, so if you’re adding a part that generates heat you can also add parts that dissipate it.  I think what Nertea’s saying is that heat management should be similar to other simple input/output math so all you really have to worry about is having more heat dissipation than heat production. So long as you do you should be able to warp to your hearts content. I believe thats what he means by “cold is good, hot is bad”. 

If it works for you, and if that's how you want to play the game, then that's wonderful.  FOR YOU.  We were told we wouldn't have to deal with colony micro-management, yet here we are being told that we will have to deal with heat in colonies - through cooling towers, shade, water, radiators, and other ways/things.  Which means colonies have to be micro-managed, lest they overheat while you're away on some other mission.

I play KSP1 where I run 1 mission at a time.  I don't want to have to focus on multiple rockets at once, so I only run one mission at a time.  Putting heat on colonies now means I have to spend less time on rockets and more time wondering if I have enough parts to deal with heat at a colony, or if I have to run more parts there to deal with heat, or if I even should abandon that colony because I didn't put it in exactly the right spot and now it's gotta be moved because it's going to overheat.

This game is about building rockets, not micro-management of colonies.  If I wanted a colony micro-management game, I'd go back to playing Civilization.  I'm here for the rockets, not the outposts.

[MechBFP]

2 hours ago, Scarecrow71 said:

If it works for you, and if that's how you want to play the game, then that's wonderful.  FOR YOU.  We were told we wouldn't have to deal with colony micro-management, yet here we are being told that we will have to deal with heat in colonies - through cooling towers, shade, water, radiators, and other ways/things.  Which means colonies have to be micro-managed, lest they overheat while you're away on some other mission.

I play KSP1 where I run 1 mission at a time.  I don't want to have to focus on multiple rockets at once, so I only run one mission at a time.  Putting heat on colonies now means I have to spend less time on rockets and more time wondering if I have enough parts to deal with heat at a colony, or if I have to run more parts there to deal with heat, or if I even should abandon that colony because I didn't put it in exactly the right spot and now it's gotta be moved because it's going to overheat.

This game is about building rockets, not micro-management of colonies.  If I wanted a colony micro-management game, I'd go back to playing Civilization.  I'm here for the rockets, not the outposts.

[snip] Your complaint sounds more like you don’t want to have to design your colony properly instead.

Almost everyone here has already played KSP1 and is looking for new challenges, and that is going to include things other than just rockets otherwise those components of the game would be pointless in the first place to even implement. 

Edited July 22, 2023 by Snark
Redacted by moderator

[Pthigrivi]

46 minutes ago, Scarecrow71 said:

Which means colonies have to be micro-managed, lest they overheat while you're away on some other mission.

I think there’s a difference between micromanagement and design. Design is what you do in the VAB, making sure your vessel has enough fuel, solar panels, batteries etc. In this paradigm colonies would behave exactly the same way. They’re just vessels that you design and deploy. The difference is they don’t move and you can add to them over time if you like. There’s no constantly going back to check if they’ve exploded. You’ll know right there in the BAE because you’ll either have enough radiators or you wont. Its the same as checking your dV in the VAB before you leave. 
 

Because of this I see no reason why you couldn’t fly one mission at a time if you so chose. Fly to Minmus, set up a beachhead. Fly to Duna for science, build a mining base on the Mun, then mount up a Dres or Jool mission. Everything will chug along nicely if you’ve designed it well, or if you haven’t it just won’t be as productive.

Edited July 22, 2023 by Pthigrivi

[regex]

14 hours ago, Nertea said:

  An overall question I'd like to answer is whether you feel like this dev blog was a useful thing for me to put together.

 

Missed this. It depends on what you consider "useful". Like I can't act on any of this information for quite some time and in all honesty I'll probably forget a large portion of it in a month (probably a good thing because the implementation might change).

"Welcome"? Yes. "Interesting"? Yes. "Useful"? Not really.

[Scarecrow71]

1 hour ago, MechBFP said:

[snip] Your complaint sounds more like you don’t want to have to design your colony properly instead.

Almost everyone here has already played KSP1 and is looking for new challenges, and that is going to include things other than just rockets otherwise those components of the game would be pointless in the first place to even implement. 

[snip]  I don't want to have to deal with this kind of stuff, [snip] to control every part of something, no matter how small.  That is EXACTLY what we are going to be asked to do with colonies, even though we've been told we won't have to.

[snip]

Edited July 22, 2023 by Snark
Redacted by moderator

[Periple]

2 hours ago, Scarecrow71 said:

If it works for you, and if that's how you want to play the game, then that's wonderful.  FOR YOU.  We were told we wouldn't have to deal with colony micro-management, yet here we are being told that we will have to deal with heat in colonies - through cooling towers, shade, water, radiators, and other ways/things.  Which means colonies have to be micro-managed, lest they overheat while you're away on some other mission.

I don't think they'll need micromanagement! You'll just need to make sure they have enough cooling capacity. If that's the case then they'll be fine left to themselves. So like Pthigrivi said above, this is a design challenge, not a micromanagement challenge. 

I do hope there will be enough UI support there so that it's easy to tell when you're running a deficit.

[snip]

Edit: Compare this to using drills and ISRU in KSP1. It's a similar design challenge: you need to get enough radiators on your vehicles to dissipate the heat they generate or their efficiency will drop to zero. (And in case of the little ISRU, you'll need either an engineer with lots of stars, or actual micromanagement to let the ISRU cool off from time to time because it generates more heat than it can dissipate no matter how many radiators you add – that is micromanagement, and the main reason I almost never bother with the little ISRU.)

Edited July 22, 2023 by Snark
Redacted by moderator

[Snark]

Many posts have been redacted and/or removed, due to:

• personal remarks and accusations
• arguing about arguing; off-topic
• getting defensive about differing opinions

Folks, please don't make things personal:

• Don't argue with opinions, but feel free to state your own.  Everyone has opinions, and people are going to disagree because they like different things.  It is not possible for an opinion to be "wrong" because it's merely a statement about what a person likes or doesn't, which is entirely personal to them.  Arguing about opinions is as silly as getting into an argument over which flavor of ice cream is better, vanilla or chocolate.  (Chocolate.)
  • This is fine:  "I disagree with your opinion, I like the opposite thing, and here's why."  (Because you're just stating your own opinion.)
  • This is not fine:  "Your opinion is wrong.  You're somehow bad because you have the opinion you do."  (Because you're trying to judge someone else's opinion, which you have no place to do.)
• Arguing about statements and claims is fine... but please do so respectfully.  If someone is making claims that are about objective matters rather than their own opinions about what's good or bad, that's fine to argue with.  State your disagreement, and cite your evidence for it.  But please don't make it personal.  Address the post, not the poster.  It's not your place to characterize what other people are like.
• Do not make personal statements.  Don't make claims about other people.  For example, saying "you don't understand", or calling people names like "elitist".  If you do that, you're talking about the person, rather than the content of what they posted.  That's a personal remark, and it's not appropriate.  Basically, if you find yourself making declarative statements with "you" as the subject, you're probably getting on risky ground here.  Take a step back and try re-wording your statement to avoid "you" language.
• Be alert to red herrings, particularly over terminology.  Not everyone interprets the same words as meaning the same things.  If two people have substantially different interpretations of what a word means, they can get into a bitter, flaming argument where they're just talking past each other, because neither of them have noticed this fact.

 

Regarding that third point (about terminology):  I bring that up because I think part of the current flare-up involves people talking past each other over the definition of a word.  The word is micromanagement.  Some people use the term to mean "any experience that requires me to tinker with detailed settings".  Other people distinguish between setup time and ongoing play time:  such people consider "micromanagement" only to be when you have to "baby-sit" a system on an ongoing basis, and they do not consider "detailed setup requirements" to be "micromanagement".

Neither of those two groups is "right" or "wrong", they just like what they like.  Which is fine.  If you like complex setup, that's fine.  If you prefer simple setup, that's also fine.  But please don't get into a rage over a simple difference of how you or someone else likes to use the word "micromanagement"-- just state what you like and why.  If you're arguing about terminology, you're probably off-topic.

• Good:  "That's not what I mean by micromanagement."
• Bad:  "You don't understand what 'micromanagement' means."

[cocoscacao]

2 hours ago, Scarecrow71 said:

I don't want to have to deal with this kind of stuff

Well, what's the point of colonies then? Also, you probably don't have to deal with them. Choose your own level of involvement.

[Omshakal]

I was wondering wouldn't it also be important to consider the effects of thermal transfer on the environment such as melting the ice or solidifying the lava?

[wasml]

17 hours ago, Nertea said:

An overall question I'd like to answer is whether you feel like this dev blog was a useful thing for me to put together.

@NerteaI found this very interesting and look forward to these dev blogs. With that said I would understand if you discontinue them because it takes too much time away from bug development/bug hunting.

[Sade]

On 7/21/2023 at 6:45 PM, Intercept Games said:

Until next time,

Chris Adderly
Senior Mechanical Concept Designer

Thanks for this nice post,

will the heat fluxes be temperature dependent? i.e. will my craft stabilize at some, higher, temperature when current total flux is positive?

[Stephensan]

1 hour ago, cocoscacao said:

Well, what's the point of colonies then? Also, you probably don't have to deal with them. Choose your own level of involvement.

3 hours ago, Scarecrow71 said:

I don't want to have to deal with this kind of stuff,

i mean subjectively that's one of the main reasons to get ksp 2 compared to ksp 1.. if not one of the most important differences between ksp 1 and 2, having a new layer of control where instead of money, there is resources to deal with..

being able to control how you want YOUR colony to grow with modular parts and making unique colonies in different areas on planets making it one of a kind is the same factor as building rocket ships and space ships, it expands and helps the game progression due to playing with technology that simply doesn't really "exist" in real life yet.

and if not, just less resources/your choice.

having better ingame resource management gives off more missions, more rockets, more fun for the people that want the extra bit of difficulty, and if not well fewer resources etc.

then again we are talking about mechanics that simply don't exist in the public view yet, and we still don't know how we will deal with resources and colonies just yet, we only know we are getting them, and some models.

we knew from the get go there will be SOME player involvement in creating colonies, resource spaceship lines, etc, it only makes sense that there is some depth in the involvement of how, and how much a player needs to be inputting..

We aren't making a mobile game when we "make" a new building it just requires a click to upgrade that creates a "dry game" or a game that lacks uniqueness or depth.. there is planning, resource management, and, in the case of here "taking care of the small things" in some order or fashion, and again if you don't want to do that it is just less resources overall.

but that is when it finally arrives, we are still in the bug fixing stage, and from what i can infer from reading not even close to 0.2 or science mode

[Vanamonde]

1 hour ago, Omshakal said:

I was wondering wouldn't it also be important to consider the effects of thermal transfer on the environment such as melting the ice or solidifying the lava?

Welcome to our forum. Since your post is about the dev notes thread, we have moved it there to keep the discussion together. 

[Pthigrivi]

6 hours ago, Stephensan said:

hope we can do long distance systems with "pump boosters" stations etc for cooling that is FAR away.

 

i wonder if there will be power lines, either just the big fat ones that "scurry" on the ground or like a traditional ones that are lifted in the air?

i hope its both, both is cool

I kind of hope for the sake of simplicity both power and coolant lines can be transmitted underground within a certain range of the colony hub. Perhaps this range could be extended with upgrades?

Edited July 22, 2023 by Pthigrivi