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SID/STAR formating


Bill Miller 828275
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Bill Miller 828275
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Currently SIDS/STARS are formatted as below. This is just an example using 4 lines of the STAR.

 

GDM3 JFK JFK ALB ALB

ALB ALB GDM GDM

GDM GDM BRONC BRONC

 

The duplication of fixes hopefully could be eliminated. It could be formatted as below.

 

GDM3 JFK ALB GDM BRONC

 

This would produce the same results and eliminate the duplication of fixes/Lat/Long. Any reasoning as to why this duplication of entries is necessary.

 

Thanks

Bill Miller

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Kenneth Haught
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I'm sure Ross will way in here, however...my gut says because the correct format for SID/STAR entry (and other areas) is LAT LON LAT LON (Lat/Lon of start fix and end fix for that line segment). By using a FIX instead of the actual Lat/Lon you can obviously make updating easier, but the program still has to pull all 4 bytes to create that line segment.

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Anchorage Deputy Air Traffic Manager

VATSIM Senior Supervisor (Team 1)

Have a question or concern? Email me at [email protected].

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Ryan Geckler
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I'm sure Ross will way in here, however...my gut says because the correct format for SID/STAR entry (and other areas) is LAT LON LAT LON (Lat/Lon of start fix and end fix for that line segment). By using a FIX instead of the actual Lat/Lon you can obviously make updating easier, but the program still has to pull all 4 bytes to create that line segment.

 

That's right. The program looks for a line, so when you put in the fix, it pulls the coords from the [FIXES] section and makes a line with them.

Ryan Geckler - GK | Former VATUSA3 - Division Training Manager

VATSIM Minneapolis ARTCC | FAA Miami ARTCC 

 

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Bill Miller 828275
Posted
Posted
I'm sure Ross will way in here, however...my gut says because the correct format for SID/STAR entry (and other areas) is LAT LON LAT LON (Lat/Lon of start fix and end fix for that line segment). By using a FIX instead of the actual Lat/Lon you can obviously make updating easier, but the program still has to pull all 4 bytes to create that line segment.

 

That's right. The program looks for a line, so when you put in the fix, it pulls the coords from the [FIXES] section and makes a line with them.

 

 

I understand that it needs this to draw the line. The question is why does the data need to be entered 2 times. If you are drawing a line from A-B-C-D why does the line need to read :

 

A A B B

B B C C

C C D D

 

Instead of A B C D

Bill Miller

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Ryan Geckler
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Because each line of text (AABB) is one single line. In order to draw another line, you need the starting point (BB) and an end point (CC).

 

That's why it's AABB|BBCC|CCDD, and so on.

Ryan Geckler - GK | Former VATUSA3 - Division Training Manager

VATSIM Minneapolis ARTCC | FAA Miami ARTCC 

 

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Ross Carlson
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I understand that it needs this to draw the line. The question is why does the data need to be entered 2 times. If you are drawing a line from A-B-C-D why does the line need to read :

 

A A B B

B B C C

C C D D

 

Instead of A B C D

 

Because whoever designed the sector file format didn't create a way to make a connected sequence of line segments. It's a very primitive format that only supports standalone line segments.

 

And the reason you need "A A B B" to create a single line segment is again just a factor of the rather basic sector file specification. Every line segment must consist of 4 fields ... the lat and lon of the start point, and the lat and lon of the end point. If you want to use a fix/vor/ndb as one of the ends, you have to specify the fix/vor/ndb twice ... once for the lon, once for the lat. You could even use the lon from one fix/vor/ndb, and the lat from another. (Why you would want to do that, I don't know, but it is possible.)

Developer: vPilot, VRC, vSTARS, vERAM, VAT-Spy

Senior Controller, Boston Virtual ARTCC

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Kenneth Haught
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...You could even use the lon from one fix/vor/ndb, and the lat from another. (Why you would want to do that, I don't know, but it is possible.)

 

Not to go off topic, but I had to LOL at that, it could make for a very interesting line setup!

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Anchorage Deputy Air Traffic Manager

VATSIM Senior Supervisor (Team 1)

Have a question or concern? Email me at [email protected].

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