Fixing table

Equator, 0 degrees -> Factor: 1 / sin(90) = 1

45 degrees -> Factor: 1 / sin(45) = 1.414

78 degrees -> Factor: 1 / sin(78) = 4.810

The further north you go, the smaller the west-east range of the search box. This deterioration is non-linear (sine function) and it’s still 70.7% halfway between the equator and pole at 45 degrees, so it may be subtle and easy to miss.

Your longitude range needs to be wider. The radius of a circle at latitude L (degrees) is sin(90 - L), so a quick fix is compenstate for the shrinking longitude radius-at-latitude by “undoing” the shrink by multiplying it: 1/sin(90 - L)

Equator, 0 degrees -> Factor: 1 / sin(90) = 1 45 degrees -> Factor: 1 / sin(45) = 1.414 78 degrees -> Factor: 1 / sin(78) = 4.810

Obviously this collapses at the poles but so do flat maps in general.

Lmao, when I first saw the pipeline map a few years ago I noticed how accurate it could be. The underlying data looked pristine despite the artificial limitations.

Maybe they were paranoid about “security” (or just did a front-end block to make someone happy or complete the requirements) or maybe they really don’t want to assume any responsibility for digging inquiries.

@TheSwavu

I just corrected it to use the specified coordinate system (NAD 83 EPSG:3424, which is actually metric) and did the trigonemetry from there in a spreadsheet. How does it look now?

@TheSwavu

Glad to hear my import worked. One must wonder how they measure heading/course in their surveys, since the heading of a straight line isn’t constant unless you’re going north or south.

Well they tried the best they could to extract the original border, but their inaccurate result becomes the legally binding, accurate boundary.

Also, I linked to that article in the main post -> “Our friends at Esri have written about this”

Thanks, Omnific.

If I want to be REALLY detailed, I must consider the fact that the width of a degree latitude is sinusoidally different from the southernmost portion to the northernmost portion. The only projection correction I did was for the starting point. For a path that deviates only a few hundred feet north of the starting point, the difference is really small anyway.