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View Full Version : Antique (or faux antique) globe projection styles--what is this one called?



ExStock
09-26-2012, 07:07 PM
(First of all, I'm a new member, so I apologize in advance. Not for anything specific; just, you know, a generalized preemptive apology.)

I am driving myself nuts, because I'm trying to find an image of a type of antique global projection map that could swear I've seen dozens of times, and honestly thought was as common as muck, until I started trying to find images of it! Perhaps I imagined it, or perhaps it's not a 'real' type of projection, but rather something made up by talented fantasy novel illustrators, and therefore harder to find by way of Google image search. Whatever it is, it's the style I'd like to use for my own fake map of a fake world, but I'd desperately like to look at a few examples of the same style before I waste time trying to recreate a vague memory.

I'm not great with cartographic terminology, and most of what I know I've learned only in the last few hours, so see above re: multi-purpose apology. :D

However, I'll try to describe my vague memory. What I'm remembering is a type of interrupted projection, if I'm using the term correctly. If you can, imagine a cross between the orange peel (http://www.ipgp.fr/~saumet/Parkfield/XN/scripts/m_map/private/exsinus.gif) / Goode homolosine (http://en.wikipedia.org/wiki/Goode_homolosine_projection) type of projection, and the renaissance globular stereographic hemisphere (http://i.telegraph.co.uk/telegraph/multimedia/archive/01366/accurat_1366052i.jpg) maps. In other words, interrupted into segments, but segments with circular edges, kind of like this:
48512
but perhaps interrupted in a different way, and definitely better, more graceful, and done in a Ye Olde style. If that makes sense.

The more I look for an example, the more I think I must have imagined the whole thing! Can anyone point me to any example of this style of projection, from any source at all?

waldronate
09-26-2012, 09:30 PM
I don't recall ever seeing a map with that particular "M" configuration. It should be easy enough to do with a program that lets you define your own projection (just shift the bottom interruptions). I know it's doable with Fractal Terrains, but the projection definitions for FT aren't the easiest to define.

How the output from FT might look:

48519 48520

And the projection block to add to Projection.txt:


Projection 92, "AE M Interrupted"
Scale 1.0
Description "Azimuthal Equidistant M interruption"

Segment "Azimuthal Equidistant", 0, -90, 0, 0, 1, 0, 0
scale 1, 1
Offset -0.5, 0.0
Effective -180, 90, 0, 0
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0 90, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.5, 0.0
Effective 0, 90, 180, 0
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, -180, 0, 0, 1, 0, 0
scale 1, 1
Offset -1.0, 0.0
Effective -180, 0, -90, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, 0, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.0, 0.0
Effective -90, 0, 90, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, +180, 0, 0, 1, 0, 0
scale 1, 1
Offset +1.0, 0.0
Effective 90, 0, 180, -90
Rotate 0
EndSegment

EndProjection


And a bonus one for Azimuthal Equidistant hemispheres:


Projection 91, "AE Hemispheres"
Scale 1.0
Description "Azimuthal Equidistant Hemispheres"

Segment "Azimuthal Equidistant", 0, -90, 0, 0, 1, 0, 0
scale 1, 1
Offset -0.5, 0.0
Effective -180, 90, 0, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0 90, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.5, 0.0
Effective 0, 90, 180, -90
Rotate 0
EndSegment

EndProjection

ExStock
09-26-2012, 09:36 PM
Oh, it doesn't have to have the "M" configuration--just the interrupted-but-with-circular-elements part! It could be configured like this:
48522 or this: 48523 or something else I can't think of, which is the whole reason I'm driving myself crazy trying to find an image of it! :)

I really was under the impression that it was common in 16th or 17th century maps... sigh.

waldronate
09-26-2012, 09:42 PM
OK, then. The above bonus item ("Projection 91") should give you an image like the following if you add it to FT:

48521

I think that someone has a template like that around here that's already done as SVG.

ExStock
09-26-2012, 09:49 PM
Thanks, and I may wind up going with that, but for now I'm still holding out for interrupted! Back to google. :)

Hai-Etlik
09-26-2012, 11:16 PM
I really can't think of any pseudocylindrical projection which would give this property or any reason you would make a projection that would have it except to get this very specific property, which really serves no purpose. You would need something like Mollweide, but "more so"; going beyond being equivalent to actually causing areas to decrease the further you get from the equator. There's just no reason to do that.

I think you've confused different maps with each other or otherwise misremembered them, or you've seem pictures that weren't real maps and didn't make sense.

ExStock
09-26-2012, 11:56 PM
I think you've confused different maps with each other or otherwise misremembered them, or you've seem pictures that weren't real maps and didn't make sense.

That's kind of the point I'm trying to convey here! (Hence my frustrated "does this remind anyone of anything" request. :) ) I don't remember what the map looked like, but I'm certain it was not anything that we would consider a faithful rendering of the planet Earth, nor, strictly speaking, a projection, at least not in the sense of applying a mathematical formula. Think more along the lines of 16thC and earlier maps, or of fantasy maps! In other words, far less concerned with what we know today is accuracy, and far more concerned with showing important things, and/or overall visual effect.

It's perfectly possible that I'm conflating two or more styles in my mind, but having spent the past several hours looking at all sorts of truly odd early "projections," I'm starting to think I've got a better chance at finding something like I'm remembering than I really expected!

(PS--this is the voice of frustration, not the voice of ingratitude! I appreciate the responses.)

ravells
09-27-2012, 02:17 AM
Apologies for the slight digression but a question for Joe (Waldronate). I've copied and pasted the new interrupted projections (I'm especially excited about projection 91) into the Projection.txt file but they are not showing up in the FT projections menu at all (even after restarting FT and then restarting the computer). This is what I've pasted at the bottom:




//---------------------------------------------------------------------------

Projection 91, "AE Hemispheres"
Scale 1.0
Description "Azimuthal Equidistant Hemispheres"

Segment "Azimuthal Equidistant", 0, -90, 0, 0, 1, 0, 0
scale 1, 1
Offset -0.5, 0.0
Effective -180, 90, 0, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0 90, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.5, 0.0
Effective 0, 90, 180, -90
Rotate 0
EndSegment

EndProjection

//---------------------------------------------------------------------------

Projection 92, "AE M Interrupted"
Scale 1.0
Description "Azimuthal Equidistant M interruption"

Segment "Azimuthal Equidistant", 0, -90, 0, 0, 1, 0, 0
scale 1, 1
Offset -0.5, 0.0
Effective -180, 90, 0, 0
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0 90, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.5, 0.0
Effective 0, 90, 180, 0
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, -180, 0, 0, 1, 0, 0
scale 1, 1
Offset -1.0, 0.0
Effective -180, 0, -90, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, 0, 0, 0, 1, 0, 0
scale 1, 1
Offset 0.0, 0.0
Effective -90, 0, 90, -90
Rotate 0
EndSegment

Segment "Azimuthal Equidistant", 0, +180, 0, 0, 1, 0, 0
scale 1, 1
Offset +1.0, 0.0
Effective 90, 0, 180, -90
Rotate 0
EndSegment

EndProjection

//---------------------------------------------------------------------------



I'm using Windows 7 (not sure if that is relevant) and FT is saved as C:/FT (i.e. it is not in the Program Files(x86) directory. Can you recommend anything to solve the problem?

Many thanks!

Ravs

@Ex Stock - I'm sure I've seen something similar to what you've described too, but I can't remember exactly what the projection looked like. I'll have a dig around...surely we can't both be mad?

waldronate
09-27-2012, 04:31 AM
That's odd. They should appear unless there's some syntax error in the file above that, like a missing EndProjection element.

48528 is my development file that has those in it. There may be some other odd things in there as well. Make a backup of your old Projection.txt file before using this one. It should just drop into your FT install directory. It won't work with the original FT, but FT Pro or FT3 should work.

ravells
09-27-2012, 05:19 AM
Lol! I was updating the projection.txt file in FT Pro, which I still have installed on my system but I forgot that I'm now using FT3 which lives in the Programs(x86) directory. Done it now and it works like a charm! I didn't know about the projection srcipts - I'm looking forward to having a play with those!

Sorry for being a dumbo!

pythor
09-27-2012, 05:00 PM
One of these perhaps? http://www.progonos.com/furuti/MapProj/Dither/ProjInt/projInt.html

Pretty sure I remember having those simple sinusoidal ones in my grade school.

LindaJeanne
09-27-2012, 05:56 PM
Or, poking around that great site that pythor linked to (when I *cough* should be doing other things. Like working), check out the Interrupted Sinu-Mollweide Projection at the bottom of this page: http://www.progonos.com/furuti/MapProj/Normal/ProjInt/ProjIntC/projIntC.html
Might that be what you were remembering?

Or the Maurer's "full-globular" map here?
http://www.progonos.com/furuti/MapProj/Normal/ProjOth/projOth.html

OK. have to close the site and get back to work now...

ravells
09-27-2012, 07:59 PM
And why hasn't this amazing site been posted in the Reference section????

Rep to you pythor for bringing it here!

Hai-Etlik
09-28-2012, 02:23 AM
Hmm, it turns out I was wrong, an interrupted Mollweide projection would give this shape if you chose the right interruptions and central meridians. It would be a rather odd way to interrupt it though. Split it into hemispheres would give you the same level of distortion with fewer breaks, or you could shift the CMs for the southern "outside" lobes from 180 to 135 degrees and get less distortion with the same interruptions.

ExStock
09-28-2012, 04:25 PM
@Ravells -- My sanity thanks you for the encouragement, as I keep wobbling back and forth between "It doesn't exist!" and "It does exist!"

I keep finding interesting things that are kindasorta what I was hoping for, but after looking at as many images as I could in the past few days, I'm leaning towards the belief that I'm remembering one or more illustrations from fantasy or historical novels, rather than a real thing. For my purposes, though, real doesn't matter!

My sanity and I have decided, however, that since my project contains different continents than our earth does, that of course their map projections would be interrupted in a different manner, and even of course that would make them think of different ways to logically project their world. So, if I want to, I can darn well make up my own method, although the more I look at it, the more I like this type of thing: 48563
I think I will play with that, and see if I can find some way to interrupt it a wee bit.

Now, I'm off to find software to help me play with continent placement. Luckily for me, the husband is an EE/mathematics PhD with the latest version of MatLab, and scaaaaads of experience using it! :D

Oh, and the reason I haven't posted sooner is because ever since my first few posts, I've been spending all my spare time on the wonderful Progonos website! :) Thank you all for your help.