SpaceSimCentral

What dictates the current frame then? Is it the nearest object/body in the system?

Overlord wrote:
What dictates the current frame then? Is it the nearest object/body in the system?
Imagine a whole system laid out flat on a large floor. Each body (star, planet, asteroid, space station) has a frame attached to it. Its a circular region that extends some distance out from the body in all directions. The larger/more massive the body, the larger the frame. Frame boundaries do not intersect however - a frame is always fully contained within another frame.The player's "current" frame, then, is the smallest one that contains the player's current position.Obviously you need to extend that out to three dimensions. There's some other complications too. The root frame (known as "System") is attached to the primary body (star or binary pair) and extends to infinity. There's also a second, smaller frame attached to every planet and space station. This frame rotates and is what makes it possible to sit on the surface of a planet and see the light/day cycle or dock with a rotating space station.There's a few other quirks, but we're getting into some subtleties of Pioneer's physics engine. The above description is right 99% of the time

Thanks Robn, makes perfect sense now.

Quote:
If you happen to have that object targeted, then you'll find your green and white velocity indicators will always be in exactly the same place.
Sorry Robn I still don't understand the white marker. I had a play recently and when I go to Barnard's Star and I target one of the orbital stations, I have the green marker and the moving white marker in different positions so I understand the permanent "where the guns point" marker, the green marker but the third white marker is at different positions.When for example I enter the Barnard's Star System and I turn manually go toward the target a little and then engage the auto, the green marker is on the left of the cross hairs and the white moving marker is on the right. This is why I saw the white (3rd) marker the direction I was heading toward taking into effect inertia etc so eventually that moving white one will align but I was confused when you said the quotation above that when I have an object targeted the green and white velocity indicators will always be in exactly the same place because they were not.Cheers Robn and thank you for your patience.

robn wrote:
If you happen to have that object targeted, then you'll find your green and white velocity indicators will always be in exactly the same place.

Styggron wrote:
I was confused when you said the quotation above that when I have an object targeted the green and white velocity indicators will always be in exactly the same place because they were not.
Because that's not what I said. if you have the "rel-to" object targeted, then your green and white velocity indicators will match. If you have an object targeted that isn't your "rel-to" (frame of reference) object, then the indicators will be different.In your Barnard's Star case, you have the station targeted but are in the star's frame ("System"). So the green target shows velocity relative to the station, while the white shows velocity relative to the star. They change as you move but the green changes more because the station is also moving relative to the star.

Putting it bluntly: Styggron, ignore the green one.

ummmm okBut I don't see why I should ignore the green one, this is what is targetted and where I have to go. ie barnard star orbital station.With Robn's post my understanding is now1. White frame of reference is the SYSTEM and in this case Barnards Star2. Green is the object I have targetted. in reference to where barnards star is so when I enter the system white and green are in different positionsSo if I make the SYSTEM frame the same as the object I target then the two markers should be the same which I believe is what Robn means.Ok I'll see where to change the white one so it matches the green ie they both target an orbital station.Sorry I might be a bit slow here....I guess I am not the right person to work on a quick start guide if I can't grasp such simple things. I'll keep at it though.

When you hook the direction of the velocity vector of the target, the green marker will follow you, that is your sub system and the target sub system has become the same sub system, then when the green speed is 0 (zero) m/s you matched the velocity vector (speed and direction) of the target, but keep in mind the targed (ad you) always has a velocity vector respect to the whole system. So when you enter in a star system the probability your ship has the same speed and direction of the target you want to rich is close to zero, for that reason your green target point to the moon (in a wrong direction).This is not always intuitive at very long distances and with slow velocity vector changes of the ship. And more, the direction of the green vector should be 'absolutized' when you and the target are in the same sub-system, i.e. if you match the direction of the target but your speed is less than the target speed, you should see the green target behind you, I guess it's always in front of you with a negative speed, I never tested (or not pay much attention, I go instinctive).

Styggron wrote:
1. White frame of reference is the SYSTEM and in this case Barnards Star
No. The white frame of reference is explicitly printed on the ship console. It's "system" only when you're far away from anything big.

All right, here's a simple experiment for you.

[*:ekv3736g]Start a new game in Sol.[*:ekv3736g]Take off, and target the sun ("Sol").[*:ekv3736g]Fly around gently. See the white diagonal speed marker? That's your direction of travel relative to Earth. See the green one? It's not moving much. It's your direction of travel relative to the sun, and shows that you, the Earth and everybody on it are moving at nearly 30km/s. That's Earth's orbit.Same applies at space stations. If you're near one, the white marker shows your direction of travel relative to the space station. If you target the planet, you can see that the green marker is direction of your travel relative to the planet. If you target the space station, the green marker is on top of the white one, until you get far enough from the station that the planet becomes your current frame of reference.Are you understanding this, or should I just make a video?

Thanks Brianetta. I'll be ok.The white marker's reference changes as is shown on the console. Eventually the green and white align.All I am not sure is why have the two moving markers.1 is the target where you want to head to and how far away it is and the other changes as you have described.

You have two markers so that you can fly manually more effectively. If you take off from a planet's surface to fly to a space station in orbit above, you need to know your direction relative to that space station. There's no point just pointing towards it, because it's moving at a few km/s, and you'll end up flying a wasteful curve as you chase after it. So, by targeting it, the green indicator shows how you're actually moving from the station's point of view, while the white one still shows you your local speed and direction (which is handy, because it's relative to important and potentially dangerous things, like buildings, mountains and even the ground).This is the thing with frames of reference. There's absolutely no way to say "this is your velocity, no arguments." All velocity (which is speed and direction, combined) is relative to something - or it's utterly meaningless.More complication: The white one is the one that works with the speed you set in Set Speed mode, unless you selected your target while holding Ctrl down. Then the set speed mode works with the green one.

Another way to easily understand the green marker (when you are in the frame of the target object, i.e. bound to its gravity field) is while running on the horizon of a very massive planet (i.e. big gas giant). The green pointer is locked to your direction, the more you approaching the 'sourface' of the planet the more the gravity pull you down, you see the green marker slowly falling down toward the planet, the ship is falling on it too also if you face the ship far from planet. You can escape if your engines have enough power and accomodating current direction (don't turn back).

Thanks hcarinae and Brianetta,I understand perfectly you need a frame of reference that part was never a problem.Thank you both for your help

All I can say is when I fly manually I only use the green marker not the moving white one.

Styggron wrote:
All I can say is when I fly manually I only use the green marker not the moving white one.
Whether that's a silly idea or not depends greatly on what you have selected as a target. If you start on Sol and target Jupiter, you'll find the green marker to be particularly useless for manual flight unless you're actually planning to head toward Jupiter. The white one is, however, very rarely useless.

Well, in manual flight I target a station I follow the green marker, I target a planet I follow the green marker, this is why I always follow the green marker. For a station it takes me right there, for a planet it takes me there for a base on the planet it takes me there so I only use that.:-)I read everything everyone wrote but the changing white marker just does not sit easily with me one day the light bulb moment will be there but for the present, the green seems to do everything I need when I target an object.

You follow the marker? Are you talking about the box-shaped marker, or the cross-shaped one? I only ask because I have not been talking about the box-shaped one at all.

I think the light bulb went on partly for me now.The box marker is yet another green marker but as you said that is not the green cross hair marker. I am clearly confusing the two by referring them as the greet marker. The one I follow is the target box green marker.

Styggron wrote:
I think the light bulb went on partly for me now.The box marker is yet another green marker but as you said that is not the green cross hair marker. I am clearly confusing the two by referring them as the greet marker. The one I follow is the target box green marker.
Glad that's straightened out. (-: Yeah, the green box is always directly on top of the target (or, if you have docking clearance at your targeted station, your cleared bay).