Determine coordinates for shapes

[+Balu-77]

Hi.

 

Many geocachers create shapes and fonts on the map using coordinates.
Which tool or program can I use to determine coordinates accurately?

 

For example, if you want an exact square on the map. How do I proceed so that the 4 corner points of the square are exactly on the map?

 

Please help!

 

 

Thank you and bye

Balu-77

[+OliLesp]

Any exemple ?

 

[+Balu-77]

Here are a few examples:

[+OliLesp]

Ok, it’s geoarts.

 

I use flops.net to make my shapes.

 

For more detailed maps, I use Google Earth Pro. I create a folder, then, on the map, I import an image of the drawing as an overlay (a transparent PNG) and create as many points as necessary.

When that's done, I save it as a .kml file, then convert it to gpx (kmltogpx) and get a gpx file with the points, which I import into flopp.net to see if it's OK.

 

Then, I create the caches and enter the virtual coordinates.

 

Also, you can use https://www.hyliston.net/apps/geoart/map.php

Edited May 16 by OliLesp

[Keystone]

I merged two duplicate threads together and deleted redundant posts.

[+arisoft]

2 hours ago, Balu-77 said:

For example, if you want an exact square on the map. How do I proceed so that the 4 corner points of the square are exactly on the map?

 

At first you need coordinates of the square in orthogonal two dimensional linear space.

Then you have to decide the scale. Lets say that one unit of this square is one nautical mile.

In this case, every y-axis unit is one (1) minute in latitude and every x-axis unit is cos(lat0) minutes in longitude, where lat0 is latitude of the origo.

If you want to use another scale just multiply or divide these values accordingly. For example, by 1852 to get meters or by 6076 to get feet.

 

This is an example how you calculate the point A(2,4) coordinates, when the origo (0,0) of the square is located at S 25 08.172, E 121 36.536.

 

Latitude = 25 degrees and 8.172 - 2*1 minutes => S 25 06.172 (You must subtract because the square is on the southern hemisphre)

 

Longitude  = 121 degress and 36.536 + 4*cos(25) minutes => E 121 40.161 (You must add because the square is on the eastern hemisphere)

 

 

 

[+Balu-77]

1 hour ago, OliLesp said:

Ok, it’s geoarts.

 

I use flops.net to make my shapes.

 

For more detailed maps, I use Google Earth Pro. I create a folder, then, on the map, I import an image of the drawing as an overlay (a transparent PNG) and create as many points as necessary.

When that's done, I save it as a .kml file, then convert it to gpx (kmltogpx) and get a gpx file with the points, which I import into flopp.net to see if it's OK.

 

Then, I create the caches and enter the virtual coordinates.

 

Also, you can use https://www.hyliston.net/apps/geoart/map.php

That helped.

 

Thank you very much.

[+Balu-77]

7 minutes ago, arisoft said:

 

At first you need coordinates of the square in orthogonal two dimensional linear space.

Then you have to decide the scale. Lets say that one unit of this square is one nautical mile.

In this case, every y-axis unit is one (1) minute in latitude and every x-axis unit is cos(lat0) minutes in longitude, where lat0 is latitude of the origo.

If you want to use another scale just multiply or divide these values accordingly. For example, by 1852 to get meters or by 6076 to get feet.

 

This is an example how you calculate the point A(2,4) coordinates, when the origo (0,0) of the square is located at S 25 08.172, E 121 36.536.

 

Latitude = 25 degrees and 8.172 - 2*1 minutes => S 25 06.172 (You must subtract because the square is on the southern hemisphre)

 

Longitude  = 121 degress and 36.536 + 4*cos(25) minutes => E 121 40.161 (You must add because the square is on the eastern hemisphere)

 

 

 

That's too complicated for me.

 

Thanks anyway.

[+arisoft]

2 minutes ago, Balu-77 said:

That's too complicated for me.

 

I know it is complicated but you asked for exact coordinates.

[+Balu-77]

4 minutes ago, arisoft said:

 

I know it is complicated but you asked for exact coordinates.

I know, but the square was just an example. This is already too complicated for me. Now I've decided on a pentagram. That would have “killed” me.

[+brekkcaching123]

I normally go on to google maps for all my coordinates. 

 

Go to google maps. For example, I'll use a HEART. 

Right click on all of the spots you want your caches to be/posted. You'll get this menu

Click on the coordinates. It will copy them. Then search them up in google maps.

Click "Save"

Then click "Favorites"
Do that for every spot of your cache. Then go in and copy the coordinates for each pin and create the cache page. It will use a different format but geocaching.com will accept it.

 

[+Balu-77]

16 hours ago, brekkcaching123 said:

Go to google maps. For example, I'll use a HEART.

How do you use a HEART???

[+Viajero Perdido]

I would use a mapping app that supports overlays.  I can think of two*: Locus Map on Android (which I also use for caching), and JOSM on a big-screen PC.  The latter is an editor app for OSM and is (cough!) a bit complicated to learn, but it works on a PC.  If using that, don't, absolutely don't upload your doodles to the public map; this is an off-label use.

 

Draw or download your desired shape, and load it into the map app as a semi-transparent overlay, so you see both shape and map at the same time.  Stretch and drag the shape into a position that you think will work, then start dropping waypoints along the shape's outline.  Pluck coords out of each.  Don't forget to check for proximity.  It'll be a lot of work.

 

(* Three, now that I notice above that the Google tool does overlays too.)

 

Edited May 17 by Viajero Perdido

[+Viajero Perdido]

By creating geo-art, you'll be supporting Groundspeak's refusal to show found mysteries at their correct location. See adjacent complaint thread.

[+brekkcaching123]

On 5/17/2025 at 3:38 AM, Balu-77 said:

How do you use a HEART???

What I meant is I will use a HEART for the shape for my geoart.

[+Hynz]

Just to leave a statement in this thread that geo-art does not only have friends and supporters:

It makes it difficult for using the map as a tool for finding interesting caches and it basically lures and encourages number oriented geocaching.

So please don't do it or at least keep it low key.

[+arisoft]

1 hour ago, Hynz said:

It makes it difficult for using the map as a tool for finding interesting caches and it basically lures and encourages number oriented geocaching.

 

Have you ever found an interesting cache which is part of a geo-art? If not, then the geo-art makes it easier to skip.

[+Hynz]

41 minutes ago, arisoft said:

Have you ever found an interesting cache which is part of a geo-art? If not, then the geo-art makes it easier to skip.

What du you mean? How to (easily) mask geo-art caches?

I mean you easy overlook caches on the map buried close by such piles of mundane and repetitive icons.

[+arisoft]

1 hour ago, Hynz said:

I mean you easy overlook caches on the map buried close by such piles of mundane and repetitive icons.

 

Ok, this is another problem I have not noticed. Usually geo-art is not placed over existing caches because they break the shape. Here are some examples that are not very bad. Do you have example of how not to make a geo-art?

 

 

 

Edited May 19 by arisoft

[+HHL]

1 hour ago, Hynz said:

you easy overlook caches on the map buried close by such piles of mundane and repetitive icons.

I didn't miss any regular placed cache in my life as GeoArts are placed most often in cache empty areas (like seas, plains, etc).

Btw: The TO asked for a help on a technical issue, NOT if GeoArts are allowed, wanted or just not wanted. That's worth another thread, but not taking over this thread.

Hans