Tiled File Import Issue with Numbering Direction

General Discussion
1

I was going to post this as a feature request, but I first want to make sure I’m not doing something wrong…

I’m using GlobalMapper v14 to grid export a large terrain in 10k x 10k peices, BT format since Geotiffs seem to lose elevation scaling.
To test, I used a simple 2 x 2 layout, making my terrain 20k x 20k.
In GM it appears as though the files are written in an Upper Left to Lower Right coordinate system like so…

| Y1-X1 | Y1-X2 |

| Y2-X1 | Y2-X2 |

But if I understand the importer correctly its expecting Bottom Left, Top Right:

| Y2-X1 | Y2-X2 |

| Y1-X1 | Y1-X2 |

I can’t seem to correct the issue in GM and apart from painstakingly renaming my 48 files I don’t see a way to account for this in the Tiled File Input dialog.

Has anyone else run into this? Does this sound like a possible to-do? Is there a workaround? Ideally I need a solution by the end of the week.

Edit: Apologies, shoulda stuck this in Bug Reports and Help.

2

Hi there,

Just to double check:

In the TFI device, have you tried using “Flip Y orientation of tiles”?

This is useful both for if the individual tiles are flipped on the Y axis, but also for situations like yours where the coordinate system is flipped – a combined flipped tile-layout coordinate system and flipped tile coordinate is the same as an flipped whole, allowing you to correctly read in scenarios where the upper-left is the origin. It will appear Y-inverted within WM, but the tileset will still fit together properly.

Here’s what I mean in ASCII-art form:

Normal WM coordinate layout


    +++
-----------
| ++ | ++ |
|X0Y1|X1Y1|
| -- | -- |
-----------
| ++ | ++ |
|X0Y0|X1Y0|
| -- | -- |
-----------
    ---

Flipped tile numbering layout (INCORRECT)

    ---
-----------
| ++ | ++ |
|X0Y0|X1Y0|
| -- | -- |
-----------
| ++ | ++ |
|X0Y1|X1Y1|
| -- | -- |
-----------
    +++

Flipped tile numbering layout + flipped tiles (CORRECT)

    ---
-----------
| -- | -- |
|X0Y0|X1Y0|
| ++ | ++ |
-----------
| -- | -- |
|X0Y1|X1Y1|
| ++ | ++ |
-----------
    +++
3

As a workaround the above should be all you need – however, I’ve heard from several peopole now in need of a upper-left coordinate system switch, so I will see about getting it added to the next feature push.

4

Flip Y produces incorrect results in an Easterly direction.

I solved my problem, but I’m not sure how…

Using the default tiled input dialog options in WM:
I enforced GlobalMapper to export the filename as name_Y_X (columns,rows) instead of name_X_Y (rows,columns) I got correct X positioning, but incorrect Y positioning.
I then enforced GM to reverse the order of the X numbering, this produced a correct North directional result.

The final tile layout is:

| Y1_X2 | Y2_X2 |

| Y1_X1 | Y2_X1 |

It maybe possible that it was misinterpreting height vs width. Cant tell, headache too strong now. :frowning: