Recent Posts

11

Gaming Community / Side paths and seeing everythi...

Last post by Legend - Yesterday at 09:32 PM

How do you handle exploring game areas like that? It sucks going the right way first haha.

12

Off-Topic Community / Downtown or uptown, which do y...

Last post by Legend - Yesterday at 09:13 PM

?

13

Gaming Community / Re: PlayStation Community Thre...

Last post by DerNebel - Sep 17, 2019, 06:37 PM

So TLOU Part II Previews and probably (hopefully) release date announcement coming next week, that's neat.

14

Gaming Community / Re: Procedural RPG OT: every a...

Last post by Legend - Sep 17, 2019, 04:49 PM

More or less I've finalized my terrain LOD method. A whopping 10 levels of detail will be used.

The highest level of detail is a 128*128 map of the area immediately around the player. It extends ~30 meters in each direction. A single pixel of this map covers ~19 inches. For comparison, the heightmap in Fallout 4 had one pixel per 18 inches. That seems like a good enough resolution considering it was good enough for a AAA game and I'm not pursuing realistic graphics.

The second LOD is another 128*128 map that covers an area twice as wide. Third is a 128*128 map four times as wide, fourth is eight times as wide, etc. After ten of these the texel density matches that of the 2048*2048 prerendered world map.

All ten maps can be packed into a single 512*512 texture so it becomes very efficient. The ground shader transforms its UV based off distance and doesn't need to change anything else.


During normal conditions all maps will be centered around the player, but this is not hardcoded. Each map is updated separately and can be positioned separately. So for example while walking down a path, the smallest map is updated almost every frame while the rest are updated sporadically. If the player teleported to the opposite corner of the world, the LOD levels could pop in from highest detail to lowest detail, opposite of normal texture streaming.

Last but not least, this system is flexible. The texture containing all the maps can be rendered at a higher or lower resolution depending on graphics settings. 64*64 maps can be packed into a 256*256 texture or 256*256 maps can be packed into a 1024*1024 texture and the shader would be fine with that.

Initially these maps will be rendered on the CPU but the end goal will be rendering them on the GPU in between frames.

[Spoiler]

15

Off-Topic Community / Re: Science General Discussion

Last post by Legend - Sep 17, 2019, 05:53 AM

Quora has a mix of answers from terrible to great.
But what if a space ship didn't have to go through an atmosphere?

Spoiler for Hidden:

I don't think it'd work for other reasons.  
Wouldn't be very practical to move for one thing.

Learning about spaceships and atmospheres has been a funny experience for me. First you think all the wings on spaceships in movies are cool cause sci fi, then you think all the wings are dumb cause physics, but then you think they're cool again cause rocket equation. In a super far future universe where rocket fuel works like car fuel alla epstein drive, dumb blocky spaceships make sense. They also make sense for generation ships or crafts with weak but highly efficient engines. For example a ship like this is freaking awesome.

A high powered laser is shot from Earth to propel the ship for the initial journey, making it circumvent the rocket equation. It would make no sense for it to ever enter an atmosphere.

A smaller ship for just our own solar system however all but needs aerobraking.



This delta v map (not sure if you've played kerbal space program) shows how much change in velocity is needed to move about the Earth, Moon, and mars. Without aerobraking, it'd take 19.5 km/s of delta v while with aerobraking it only takes 13.1 km/s of delta v. Because the fuel needed to accelerate that extra 6.4 km/s has mass, it takes even more fuel just to bring that extra fuel.

Say we have a rocket that weighs 100 tons when empty that has 100 tons of cargo and engines with a 350 ISP (this is kinda similar to SpaceX's Starship). To have 13.1 km/s of delta v, it needs 8,900 tons of fuel. However to have 19.5 km/s of delta v, it needs a whopping 58,500 tons of fuel. It's goes from insane but maybe possible in the future to ludicrous. Aerobraking can save so much fuel that I can't imagine any rocket with strong enough engines would ignore it. NASA's Mars transfer vehicle can't aerobrake for example because it would get stuck in the planet's gravity well.

Spoiler for Hidden:

<br>I think I like rockets too much.<br><br><div style="margin:20px; margin-top:5px"><div class="smallfont" style="margin-bottom:2px"><b>Spoiler</b> for <i>Hidden</i>: <input type="button" value="Show" style="width:60px;font-size:10px;margin:0px;padding:0px;" onClick="if (this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display != '') { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = ''; this.value = 'Hide'; } else { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = 'none'; this.value = 'Show'; }"></div><div class="alt2" style="margin: 0px; padding: 6px; border: 1px inset;"><div style="display: none;"><br>Nuclear rocket engines are about as good as we could hope for in any foreseeable future. With an ISP of 1,000, our theoretical single stage rocket would need only 600 tons of fuel with aerobraking to land on Mars. Without it would need 1,300 tons of fuel. Much nicer but still shows how aerobraking is still very important for near term sci fi ships.<br><br>Of course a light weight antimatter drive could do it with just .027 tons of fuel or .04 tons without aerobraking, but if you have a ship with those capabilities then all our notions about space travel are out the winder.<br><br><div style="margin:20px; margin-top:5px"><div class="smallfont" style="margin-bottom:2px"><b>Spoiler</b> for <i>Hidden</i>: <input type="button" value="Show" style="width:60px;font-size:10px;margin:0px;padding:0px;" onClick="if (this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display != '') { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = ''; this.value = 'Hide'; } else { this.parentNode.parentNode.getElementsByTagName('div')[1].getElementsByTagName('div')[0].style.display = 'none'; this.value = 'Show'; }"></div><div class="alt2" style="margin: 0px; padding: 6px; border: 1px inset;"><div style="display: none;"><br>All this is metric tons.<br></div></div></div><br></div></div></div><br>

[Spoiler]

16

Off-Topic Community / Re: Science General Discussion

Last post by the-pi-guy - Sep 17, 2019, 03:41 AM

Quora tends to have weird answers. That wouldn't work at all.

Quora has a mix of answers from terrible to great.

It takes a lot of energy to launch stuff into space, the person is right that in situ resource utilization is important, but no one argues the resources should be used as is lol. Mine, refine, and manufacture all in space.

A hollowed out asteroid would make a horrible ship. Way too heavy to move and way too fragile. A purpose built ship with heat shields would handle aerobraking so so so much better. The massive asteroid would have no way to control itself in the air and would need to plunge into the thicker lower atmosphere to really slow down. It'd be nearly impossible to end up in a desired orbit. Every real world spaceship needs to fly like a "plane" to control where they go. This video from the sixties shows how it worked with Apollo:


Interestingly enough, SpaceX's BFR was actually designed to enter the Martian atmosphere upside down.
This would allow the rocket to stay in the upper atmosphere longer and bleed off more speed before entering the thick lower atmosphere. Without having this control, the rocket would have too much velocity and would "bounce" off.

But what if a space ship didn't have to go through an atmosphere?

Spoiler for Hidden:

<br>I don&#39;t think it&#39;d work for other reasons.&nbsp; <br>Wouldn&#39;t be very practical to move for one thing.<br>

17

Off-Topic Community / Re: Science General Discussion

Last post by Legend - Sep 17, 2019, 02:37 AM

https://www.quora.com/How-would-a-realistic-very-large-spaceship-look-like/answer/Dave-Consiglio

Quora tends to have weird answers. That wouldn't work at all.

It takes a lot of energy to launch stuff into space, the person is right that in situ resource utilization is important, but no one argues the resources should be used as is lol. Mine, refine, and manufacture all in space.

A hollowed out asteroid would make a horrible ship. Way too heavy to move and way too fragile. A purpose built ship with heat shields would handle aerobraking so so so much better. The massive asteroid would have no way to control itself in the air and would need to plunge into the thicker lower atmosphere to really slow down. It'd be nearly impossible to end up in a desired orbit. Every real world spaceship needs to fly like a "plane" to control where they go. This video from the sixties shows how it worked with Apollo:

Interestingly enough, SpaceX's BFR was actually designed to enter the Martian atmosphere upside down.

This would allow the rocket to stay in the upper atmosphere longer and bleed off more speed before entering the thick lower atmosphere. Without having this control, the rocket would have too much velocity and would "bounce" off.

18

Off-Topic Community / Re: Science General Discussion

Last post by the-pi-guy - Sep 17, 2019, 01:44 AM

https://www.quora.com/How-would-a-realistic-very-large-spaceship-look-like/answer/Dave-Consiglio

19

Off-Topic Community / Re: TV Show Thread

Last post by Xevross - Sep 16, 2019, 10:22 PM

Somewhat.  
They've been talking about wanting longer seasons.
Season 3 was supposed to be 14 episodes.  

Thought the contract would give them that opportunity.  

Hmm I suppose. I guess if 14 episodes meant there would be a few duds then I'm okay with there only being 10.

20

Off-Topic Community / Re: TV Show Thread

Last post by the-pi-guy - Sep 16, 2019, 09:32 PM

Were you expecting more?

Somewhat.  
They've been talking about wanting longer seasons.
Season 3 was supposed to be 14 episodes.  

Thought the contract would give them that opportunity.