Results 1 to 10 of 10

Thread: Mecator Map Vector Template

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Guild Adept Facebook Connected aquarits's Avatar
    Join Date
    Nov 2012
    Location
    São Bernardo do Campo - SP - Brasil
    Posts
    395

    Default

    Is possible use it in Photoshop? Looks like i lost some feature when use Illustrator to open the file.
    When i open i just see a layer like your first pic.


    you know that i was looking for it ty man!
    Last edited by aquarits; 01-04-2013 at 03:31 PM. Reason: typos correction

  2. #2
    Guild Journeyer MarkusTay's Avatar
    Join Date
    Nov 2008
    Location
    Long Island, USA
    Posts
    135

    Default

    Okay, first off, thanks for sharing.

    Second, I am having trouble wrapping my mind on how to use this (not sure if I am just having a major brain-fart or what). When I look at most (Earth) maps with this, the map is always wider then it is tall. Even most fictional maps are presented like this. How is this is a square? If you show a round globe flattened onto a rectangular piece of paper, shouldn't it be twice as wide as it is tall? (if the globe is perfectly round.)

    Is it that most maps cut-off a major part of the top and bottom of this grid? (and I get that the top and bottom edges really represent a pinpoint and not a line as illustrated)

    Where is my thinking going askew here?

    EDIT: I think I answered my own question - most maps ARE indeed missing pieces of this. the answer was (literally) right in front of me - I have a huge world map right above my monitor on the wall. Apparently the entire bottom row and at least half of the top boxes are missing.

    Thanks again - someone ask me for a 'timezone' map for the Forgotten Realms awhile back, and this will work-out perfectly. I just need to add the lines for the arctic and tropic zones now.
    Last edited by MarkusTay; 01-04-2013 at 03:26 PM.

  3. #3
    Software Dev/Rep Hai-Etlik's Avatar
    Join Date
    May 2009
    Location
    48° 28′ N 123° 8′ W
    Posts
    1,333
    Blog Entries
    1

    Default

    Quote Originally Posted by MarkusTay View Post
    Okay, first off, thanks for sharing.

    Second, I am having trouble wrapping my mind on how to use this (not sure if I am just having a major brain-fart or what). When I look at most (Earth) maps with this, the map is always wider then it is tall. Even most fictional maps are presented like this. How is this is a square? If you show a round globe flattened onto a rectangular piece of paper, shouldn't it be twice as wide as it is tall? (if the globe is perfectly round.)

    Is it that most maps cut-off a major part of the top and bottom of this grid? (and I get that the top and bottom edges really represent a pinpoint and not a line as illustrated)

    Where is my thinking going askew here?

    EDIT: I think I answered my own question - most maps ARE indeed missing pieces of this. the answer was (literally) right in front of me - I have a huge world map right above my monitor on the wall. Apparently the entire bottom row and at least half of the top boxes are missing.

    Thanks again - someone ask me for a 'timezone' map for the Forgotten Realms awhile back, and this will work-out perfectly. I just need to add the lines for the arctic and tropic zones now.
    There are different projections. You are thinking of Plate carree but this is Mercator.

    Plate carree is a special case of Equidistant Cylindrical. You can think of it as measuring the distance along the equator, and then turning 90 degrees and measuring the distance along the meridian. Then you plot that as if it were flat. For other equidistant cylindrical projections you can replace the equator with some other parallel called a standard parallel. (actually each such projection has 2 standard parallels, one on either side of the equator.)

    If you are at the standard parallel, everything is fine. As you move away from it, the map gets distorted. Stretched out east to west as you move toward the poles, or pinched together as you move toward the equator (unless the equator is both standard parallels as in Plate Carree)

    In plate carree, yes, the aspect ratio for a map of the whole globe is 2:1, but the projection is only generally used for intermediate data to be manipulated in other ways, or sometimes for thematic maps. It's ugly and distorts both angles and areas. If you use other standard parallels, the width is twice the cosine of the standard parallels times the height: 2*cos(latitude)*height.

    Mercator is designed to preserve angles, (In fact it goes further and preserves compass bearings) and is meant for marine navigation. It does this by stretching out everything north-south by the same amount it is stretched east-west, and otherwise works like plate carree. This means that things get bigger as you move toward the poles, and as the poles are stretched out infinitely, they are infinitely far away. Notice that the parallels (horizontal lines) spread out as you move away from the equator. Roughly speaking it preserves shapes by distorting area.

    So Mercator maps are always missing the poles. In this case I cut it off at 85 N/S although it's usually a bit lower, which is why most Mercator maps have a higher aspect ratio. You can cut off the excess if you want.

    Mercator was used for global general reference maps for a long time, although it's not actually a very good choice for this. (The decision was made by publishers, not cartographers) Modern reference maps tend to use hybrid projections like Winkel Tripel which are generally oblong shapes rather than rectangles and don't need to chop anythting off. For a time zone map, a cylindrical (comes out as a rectangle) projection like either of Mercator or Equidistant Cylindrical does have some advantage in that it will make the zones come out as nice vertical stripes rather than wacky crescent shapes.

  4. #4
    Software Dev/Rep Hai-Etlik's Avatar
    Join Date
    May 2009
    Location
    48° 28′ N 123° 8′ W
    Posts
    1,333
    Blog Entries
    1

    Default

    Quote Originally Posted by aquarits View Post
    Is possible use it in Photoshop? Looks like i lost some feature when use Illustrator to open the file.
    When i open i just see a layer like your first pic.


    you know that i was looking for it ty man!
    I'm afraid I don't know much about the Adobe toolchain. The SVG file consists of multiple groups which I imagine Illustrator would convert to its own groups. In Inkscape, the top level groups are treated as being "layers" and IIRC I set the bottom layer to be hidden by default. You probably only need that lower layer if you are working in Inkscape and want to take advantage of the mask I built into it. If you just want to make an overlay to use in Photoshop or another raster graphics editor, you can adjust the size and style and then export at your desired resolution and load into the raster editor. If all else fails you could download Inkscape.

    You can trim off the top and bottom but you probably want the left and right edges to be the edges of your map extent (they should be flush against the borders)

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •