How to deal with irregular shaped maps?

Hello,

I am working on an automated approach to converting NOAA BSB [nautical] charts to PNG and MAP files for import via the OruxMaps Desktop.

I have encountered 2 problems in specifying the map limits in the .map file via the lines MMPXY, MMLLn:

The preamble to the KAP file (the "meat" of the BSB chart) has parameters describing the number of X and Y pixels, but these parameters include
a lot of white margin on all sides of the active chart, thus cannot be used for this purpose. Many of the charts are skewed (meridians are not parallel to the Y axis) and have to be rotated to interpret the REF entries and search for the actual corners. I have been searching the coordinate list specified by REF entries and searching for corners, but a simple search of a skewed chart misses the corners most times.

Any advice would be gratefully accepted.

Even worse, some charts have a corner missing (12372_1 is an example). If I add a fifth MMPXY line to the .map file, will OruxMapsDesktop correctly interpret this as the inner corner of the missing region?

16319874 wrote:Hello,

I am working on an automated approach to converting NOAA BSB [nautical] charts to PNG and MAP files for import via the OruxMaps Desktop.

I have encountered 2 problems in specifying the map limits in the .map file via the lines MMPXY, MMLLn:

The preamble to the KAP file (the "meat" of the BSB chart) has parameters describing the number of X and Y pixels, but these parameters include
a lot of white margin on all sides of the active chart, thus cannot be used for this purpose. Many of the charts are skewed (meridians are not parallel to the Y axis) and have to be rotated to interpret the REF entries and search for the actual corners. I have been searching the coordinate list specified by REF entries and searching for corners, but a simple search of a skewed chart misses the corners most times.

Any advice would be gratefully accepted.

Even worse, some charts have a corner missing (12372_1 is an example). If I add a fifth MMPXY line to the .map file, will OruxMapsDesktop correctly interpret this as the inner corner of the missing region?

Could you send me a KAP file? -->oruxuro@gmail.com

Perhaps I could help you.

orux

I haven't found a way to upload a file, and there is no simple URL, but
following this recipe will get you the file:

I have not been able to make the URL visible in the message. I hope you can see it!
Go to this site:


select the CT charts (state of Connecticut)
You will get a ZIP file downloaded.
Go to 12372 folder in this ZIP.
The file 12372_1.KAP is a good example of the problems I have encountered.


thanks,
Micheal

16319874 wrote:I haven't found a way to upload a file, and there is no simple URL, but
following this recipe will get you the file:

I have not been able to make the URL visible in the . I hope you can see it!
Go to this site:


select the CT charts (state of Connecticut)
You will get a ZIP file downloaded.
Go to 12372 folder in this ZIP.
The file 12372_1.KAP is a good example of the problems I have encountered.


thanks,
Micheal

Hi, Micheal;

I have been able to create an OruxMaps map from a .kap file using Ozi for creating a .map file, and bsb2png for converting the .kap file to png.

Then, with OruxMapsConverter was easy.

I will write a howto.

orux

Ozi is not a great option for me: I use MacOS.

Is there another way?

I am willing to get my hands dirty in the KAP file but I need more information regarding how to
treat the indented corner (fifth coordinate)

Micheal

16319874 wrote:Ozi is not a great option for me: I use MacOS.

Is there another way?

I am willing to get my hands dirty in the KAP file but I need more information regarding how to
treat the indented corner (fifth coordinate)

Micheal

Hi, Michael;

I think I can create a command line tool for calibrate those maps. Let me some days.

But I need more maps/examples, could you contact with me:--> oruxuro@gmail.com

orux