Weather Routing

[rgleason]

Without getting off the focus of fixing this read only bug, just for discussion, I am adding a link to a page at Altendorff.co.uk which explains there are two ways to calculate optimal polars:

1. Isochrone Method - calculates & stores an intermediate grid of data from actual boat motion for a fixed period of time for the isochrones (lines representing the same amount of time).
2. Local Knowledge Method -Dave Brayshaw (Advantage Software)
   • There is an article that Dave wrote (not good type) but it is worth reading Seahorse Routng Article
   • Grid of Columns and Rows between Start and Destination widening in the middle and narrowing at the ends (a diamond of points). Calculate the time it takes to sail from one grid point to the next and determine the sequence of points that results in the least amount of time. You can increase the width of the columns or narrow them for the situation. The program uses the polar to find the upwind speed to use between points. The LK method shows the optimal "average" solution between points...
   • Difference between Advantage and Deckman --- Tides
   • About Racing Software - WxRte is not racing software, it is cruising software, but the differences are useful info .

[Petr-Singa]

rgleason,

Thank you for your promt reply.

Looking forward to next good news from you.

Petr

[rgleason]

Petr-Singh
What OS are you using?

[rgleason]

I'm trying to determine if this is a Win10 permissions issue. There are reports about Win10 updates .. search on "Win10 user read only" or "Win10 documents read only"
I haven't done anything though... just investigating.

[Petr-Singa]

rgleason,

my OS is Windows 10, 64 bit, Version 1709

Petr

Originally Posted by Petr-Singa

rgleason,

Thank you for your promt reply.

Looking forward to next good news from you.

Petr

[rgleason]

Thanks,

I've checked it. I don't believe it is the read only settings, when I go down to the next folder, everything is read/write/execute. So it has nothing to do with read/write IMHO
Also, why does the Plugin save changes in the Polar Tab when it is on Grid Tab but not when they are changes in the Dim Tab?
As I said originally, it is a bad command or statement in the Dim Tab section of the program.
The fact that it is saving properly from the Grid Tab indicates it has nothing to do with read-write issues., and indicates it is a program issue!


https://github.com/seandepagnier/wea...ment-374002744

[rgleason]

We've been very lucky this week, a couple of good programmers have been working on Sean's plugin fixing and creating new features.

Many thanks to Theeko who has created the Optimal Routing Wind Feather and other excellent improvements.

Also Stelian deserves far more than 2 jelly beans for his work fixing the Polar Editor so it would save and complete without upsetting OppenCPN. It was a tough one and it took considerable persistence finding the problems. Now users have a workable Polar editor built into Weather Routing which is much easier to use than Notepad++ because rows and columns are lined up properly. Thank you Stelian!

The update will be available at some point soon when Sean merges some of the final pull requests.

[rgleason]

See Current Informed Routing Plugin

Later Response with Tracker & Issues re use of Tide Harmonics
http://www.cruisersforum.com/forums/...ml#post2602231

[wholybee]

Version 1.11 compiled for Mac:

https://holybee-my.sharepoint.com/:u...5-Ung?e=tDE5dr

It took my awhile because my development computer is on my boat, and land problems have kept me away. Compiled without too much headache. I'm still on osx 10.10.5 and wxWidgets 3.0.2 is apparently broken with 10.10.x so I used wxWidgets 3.0.4. Hopefully the minor version bump doesn't make it incompatible.

[wholybee]

Originally Posted by rgleason

I agree, users should not have to look for it in the code.

You could take out the word "Wind" to shorten it, or you could use wxformbuilder to make the entries so they are visible.

Also I am still trying to understand how & why the graph actually changes, in Polar, say between True Wind Speed and True Wind Direction. I am trying to visualize/understand this change and what the various polar scales represent for each graph.

Also Gille asked what the "Vert" check does and I have the same question.

Thanks!

This bothered me immensely, and was an easy fix. Just comment the following line in WeatherRoutingUI.cpp

1786: // m_cPlotVariable->SetMaxSize( wxSize( 120,-1 ) );

Not sure how it affects other OS's, but it displays fine in Windows after that.

[seandepagnier]

I have just added support for sparse polars.

So polars with blanks or 0, can be used. This was discussed on github. I think it works pretty well, but needs some testing. The idea is, you can use polars even without complete data.

It's really easy to make polars now, you can specify just a few values, or even just values at the corners of the grid. For example, you could specify a polar like this:

twa/tws;6;8;10;12;14;16;20
45;4;;;;;;7
52;;;;;;;
60;;;;;;;
70;;;;;;;
90;;;;;;;
105;;;;;;;
120;;;;;;;
130;;;;;;;
140;;;;;;;
150;;;;;;;
175;3;;;;;;8

For interpolation it uses the sailboat transform, so it gives somewhat realistic sailing speeds even with very few datapoints.

It doesn't extrapolate... so if you specify 6 knots and 10 knots, it won't calculate 15 knots. Same for wind directions, it won't try to determine values above or below actual measurements... Should it?

[rgleason]

Sean,
Wow. I ran across your very mathematical Performance calcs document and want to go back to read it better. I'm impressed again. I know the 3rd Performance tab with ship characteristics is in Edit Polar. I havent tried this recently. Is it working still?

I like what you've done with empty fields. Without having thought about it enough, what about interpolating up to 1-2 or 3 steps at most, to start out and see how that works?

-----
Wholybee,

I tried this:
This bothered me immensely, and was an easy fix. Just comment the following line in WeatherRoutingUI.cpp
1786: // m_cPlotVariable->SetMaxSize( wxSize( 120,-1 ) );
Not sure how it affects other OS's, but it displays fine in Windows after that.

It works but breaks the wxFormbuilder fbp process, also the titles are way too big and push out the checkbox option for Full Polar.

I would like to shorten the titles so we can see them and keep the Full polar checkbox

• TWA/TWS
• AWA/AWS
• TWA/AWS
• AWA/TWS

https://github.com/seandepagnier/wea...ment-375914470

I think the code is changed here, but I am not sure
https://github.com/seandepagnier/wea...ment-375916838

Can someone make a PR?

[rgleason]

Sean,
It struck me. This is really good, just a few known points and it completes, nice.
"For interpolation it uses the sailboat transform, so it gives somewhat realistic sailing speeds even with very few datapoints."

You wrote:
https://github.com/seandepagnier/wea...ment-373899351

I can agree that .0001 can be used to basically stop. But this is different from not propagating. This will again try to propagate at the next time step. This could mean a very different result if you are trying to avoid only beating closer than 60 degrees above 30 knots. Maybe also you want to avoid beam seas above 40 knots as well, but angles of 50-60 or 120-160 are ok. Using a value of .0001 won't work, as technically you cannot "hold" position any more easily than just sailing on a useful course. The algorithm will start sailing again when the wind drops.

Using a value of 0 to indicate that you cannot sail on this condition could have the same effect as hitting a boundary or land, and stop propagation. This could be very useful, and the routing will try to find other ways to reach the destination. It makes most sense to me, to use 0 to indicate "impossible" but if not, how else can we implement it? Could the value of "-1" be used instead? Would this be more compatible to other routing programs?

Why do people frequently make broken polars full of 0?
Why not simply leave fields empty if data isn't available

So, now, "O" is hard, the boat won't go there. If it is "blank" you just don't have data for that condition. It seems if you have scanty data at the ends with "blanks" between, the polar miraculously gets completed! However if there are just a few "blank" spots what happens? How are things calculated of this polar? Is the interpolation done on the fly during "Computation" of a Configuration?

[wholybee]

Originally Posted by rgleason

Sean,

-----
Wholybee,

It works but breaks the wxFormbuilder fbp process, also the titles are way too big and push out the checkbox option for Full Polar.

I would like to shorten the titles so we can see them and keep the Full polar checkbox

• TWA/TWS
• AWA/AWS
• TWA/AWS
• AWA/TWS

I would sure like to see it work in Windows like it does on the Mac. The size of the control is small, but the drop down sizes large enough to show the complete text.

Maybe I'll look at wxFormBuilder when I get frustrated with looking at NMEAconverter_pi.

[rgleason]

Oh Dear Warren, I know how you feel. We'll get there. I've been focused on some other (Architectural) things today.