o7 fellow explorers!
i'm trying to program a star plotting framework in Python and need some infos about the galaxy map size.
I've read here that the the galaxy is divided in 1280³ ly sectors (cubes) and here that the binary field for sectors in X and Z in the "id64" identifier of every system allows for 7 bit, which translate to 128 possible numbers. The Y part has 6 bit, which means 64 possible states.
So the maximum possible ly range is 128 x 1280 ly in X and Z = 163840 ly edge length and on the Y axis we have 64 x 1280 ly = 81920 ly.
But the image commonly used for galaxy maps, like here: https://www.edsm.net/en/galactic-mapping
(source) only measures (based on the coordinates i got from the edges of edsm.net map):
89674 x 90006 ly which cleared up for measuring errors, should be 70 x 70 sectors = 89600 x 89600 ly.
Does anyone know the exact dimensions of this image in ly and sectors?
Is that the range where visitable stars are placed - 89600 x 89600? And 163840 x 163840 is only the max possible coordinate range based on the available bits?
I had a hard time placing a cube of stars in 100 ly range, with its center being Sol, inside my 3d plot because i assumed the galaxy image was 163840 ly in length.
So i have the 2 types of coordinates for Sol:
But if i measure the pixel coordinates (0,0,0 is the center) on the map i get: 30, ?, 24740 for the edsm Sol location (yellow marker). And cyan is the offset location -25, 21, -25900 (which should be correct?)
I want my map to be accurate but if i don't know the exact dimensions of the image it's kinda hard placing systems in the right spot. The image is just a backdrop - but i still want to make sure that imported stars are placed in the right spot.
I just wanted to know if the image is exactly 70 x 70 sectors in size and if there is more extra offset from the center i am missing.
Do you know a site where i can find more info about this? The elite wiki does not go into the details of the map and sector ly sizes. I know the in-game coordinates of systems are based on Sol 0,0,0 - so the most important thing to know would be how to to get the accurate offset from the center of the image (or the correct sector dimensions).
Yellow: edsm Sol location (measured: 30, ?, 24740)
Cyan: 25, 21, -25900 (visually not in the right place!)
@marx Since you wrote a very helpful thread about the structure of the galaxy map - could you please help me understand why i get this offset between measured and implemented coordinates?
i'm trying to program a star plotting framework in Python and need some infos about the galaxy map size.
I've read here that the the galaxy is divided in 1280³ ly sectors (cubes) and here that the binary field for sectors in X and Z in the "id64" identifier of every system allows for 7 bit, which translate to 128 possible numbers. The Y part has 6 bit, which means 64 possible states.
So the maximum possible ly range is 128 x 1280 ly in X and Z = 163840 ly edge length and on the Y axis we have 64 x 1280 ly = 81920 ly.
But the image commonly used for galaxy maps, like here: https://www.edsm.net/en/galactic-mapping
(source) only measures (based on the coordinates i got from the edges of edsm.net map):
89674 x 90006 ly which cleared up for measuring errors, should be 70 x 70 sectors = 89600 x 89600 ly.
Does anyone know the exact dimensions of this image in ly and sectors?
Is that the range where visitable stars are placed - 89600 x 89600? And 163840 x 163840 is only the max possible coordinate range based on the available bits?
I had a hard time placing a cube of stars in 100 ly range, with its center being Sol, inside my 3d plot because i assumed the galaxy image was 163840 ly in length.
So i have the 2 types of coordinates for Sol:
- Offset from center: -25, 21, -25900
- Galactic coordinates 49985, 40985, 24105 (where is xyz = 0,0,0 here?)
But if i measure the pixel coordinates (0,0,0 is the center) on the map i get: 30, ?, 24740 for the edsm Sol location (yellow marker). And cyan is the offset location -25, 21, -25900 (which should be correct?)
I want my map to be accurate but if i don't know the exact dimensions of the image it's kinda hard placing systems in the right spot. The image is just a backdrop - but i still want to make sure that imported stars are placed in the right spot.
I just wanted to know if the image is exactly 70 x 70 sectors in size and if there is more extra offset from the center i am missing.
Do you know a site where i can find more info about this? The elite wiki does not go into the details of the map and sector ly sizes. I know the in-game coordinates of systems are based on Sol 0,0,0 - so the most important thing to know would be how to to get the accurate offset from the center of the image (or the correct sector dimensions).
Yellow: edsm Sol location (measured: 30, ?, 24740)
Cyan: 25, 21, -25900 (visually not in the right place!)
@marx Since you wrote a very helpful thread about the structure of the galaxy map - could you please help me understand why i get this offset between measured and implemented coordinates?
