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posted version 1.98c :

Download file http://www.tecepe.com.br/nav/vrtool/vrtool.zip
md5 E000DBF5352F3BD510904621C70D045B

changes
- Routing - Option to disable rectangle sailing (for VORG)
- Corrections and improvements in routing
- Import NOAA winds up to 384h
- Earth 3D view changes

Routing params:
VORG 11- iso=1 branches=29 max ang=100 wake=40 iso spacing=1% [x]Add branches at isochrones
VR- iso=1 branches=19 max ang=100 wake=40 iso spacing=1% [x]Add branches at full degrees

As usual, unzip vrtool.exe in \program files\vrtool\ (or whatever folder you installed vrtool in)
(requires version 1.97 or latter installed. If you dont have it, use the full installer first)

Omar, what an amazing improvement to the weather routing - that is now a very powerful tool. Thanks for that, and well done!
A question: What does the "iso point spacing" setting do?

mclean wrote:What does the "iso point spacing" setting do?

"iso point spacing"- This is the density of points kept in the isochrone.
Default is 1 (for 1% of the distance to start/destination).
If you increase to 2, for example, you will keep fewer points, more spaced,
resulting in a faster calculation but with a little less detail. This is a new parameter.

Other important Weather Routing params are:

[ ]Add branches at isochrones - When the boat reaches the isochrone line,
do a round of track branching in several directions. [x]Checked for VORG. [ ]Optional for VR (def-=unchecked)

[ ]Add branches at full degrees - Has to do with the rectangles
in VR races. Do a round of branching when the boat crosses a rectangle border.
[ ]Unchecked for VORG. [x]checked for VR
( Parameter is badly misnamed, because it is actually the 30' lat/lon lines. )

isochrone interval - Time between sucessive isochrones, in hours.
For VORG use 1 or 0.5. For VR it can be longer (like 3).
Note that at isochrones the software does the tree prunning, reducing the point count.
Longer intervals will result in large number of points and sluggish calculation.

show isochrones - This controls which isochrones are exported to the desktop
when you click [Add isochrones] button. Default = 6h.
Tip: You don't have to restart the calculation if you change that,
because the track tree is still in the memory. You can change and insert the isochrones again.

number of branches - Number of track segments created at each branch generation.
The software adds one track direct to the destination and a number segments to each side,
spaced 5 deg (a little less in close hauled direction). So if you choose 21 for example,
you have 10 segments to each side (up to 50 degrees). In the classic polar database there
are 62 directions. Setting this param too high causes the computer to choque

Max angle to the destination - removes branches that point more this
angle to the destination. Using 110 for VORG.

Omar congratulations for a great job and a valuable tool for the sailing community!

It seems to me branches in full degrees in VORG 2011-12 are more important than branches at isochrones, as that's where the wind changes and where course changes should consequently happen... Any comments?

Also, my impression is "branches at full degrees" also branch at isochrones. Is this correct? Why not use both checkmarks if we want both brancings?

Thanks for your efforts

ageor wrote:Why not use both checkmarks if we want both branchings?

The parameter description is a little confuse here. This is what the branching options mean:



"branch at full degrees" should be "branch at wind rectangle borders".
This is to be used for VR races, where wind changes abruptly
when moving from one degree rectangle to another. For VORG 11, uncheck this.
It makes the calculation slower because the geometry is more complicated.

"branch at isochrones" is optional for VR races ,
but mandatory for VORG 11 continuous winds.
Also for VORG use isochrone interval no larger than 1 hr.

Do not confuse "plain" isochrones with those when the wind changes.
Wind changes are always branching points, since the boat course has to be adjusted.

Unnecessary branching results in slower calculation.
I recommend using only one branching mode checked, depending on the race.

I have observed that sometimes its large differences between interpolations of winds in VORG and VRTool and other GRIB-viewers. For example tonight we got at 24d40'N 51d50'E Ugrib: 234/5.6, VRTool: 53/4.4, zezo: 113/4.2 and VORG: 113/4.26
Here is also a link with interpolation questions: http://www.grib.us/Forum/tabid/55/forumid/4/threadid/206/scope/posts/Default.aspx
It would be great if VRTool also adapt the same interpolation as VORG.

dear Omar
congratulations your routing modul is good
but if I modify the routing map monoBmpGSHHS_24k12k.bmp I cant use it
I try also with a file give par icoo but it the same thing if 1 activate landing detection (even with no land on the road) the result is :

Construction de l'arborescence...
résolution de la grille de vent= 1.00 °
intervale des prévisions=12h
----
isochrone = 1h
points = 1
tracés = 0
tri...
----
Calcul terminé
temps de calcul = 0.03 sec
Distance orthodromique = 4.8 NM
le plus court = NAN NM
le plus long = NAN NM
points = 1
tracés réussis = 0


is it possible to modify it ? thanks for your answer

g1vaguealame,
I don't know why you got this result.
If you edited the collision detection bitmap, make sure
you save it as a 1 bit monochrome Windows bitmap (.bmp format).
Then make sure you go to the collision detection module,
type complete filename and click load.

Misil208 wrote:I have observed large differences between interpolations of winds in VORG and VRTool and other GRIB-viewers.

I tried to place a flexible wind interpolation algorithm. For VORG, it seems that interpolation in position
is done using a bilinear method. You may try bicubic too.

Areas where wind speed/direction change fast with position may present
larger differences, due to interpolation implementation details.

g1vaguealame,
I don't know why you got this result.
If you edited the collision detection bitmap, make sure
you save it as a 1 bit monochrome Windows bitmap (.bmp format).
Then make sure you go to the collision detection module,
type complete filename and click load.

I am sure that i make the good manipulation with windows 7 and adobe but it's not good
i try also to save the same file then reload without success