Automatically generate NAPA patch model

[Alexanov]

Thank you very much for you kind reminder, Alexanov.

This is hard work. If you need to know something more - just ask. I pass it many years ago, even before The nurbs book appear). This is still very interesting for me.

 

[bingli]

This is hard work. If you need to know something more - just ask. I pass it many years ago, even before The nurbs book appear). This is still very interesting for me.

Dear Alexanov,

Thanks very much.

I visited your website with great interest last night.

You have developed a great software with user friendly UI and also various functions based on NURBS.

And the videos are also very impressing.

Our software is based on BSpline and is much easier compared to your software which is based on BSurface.

Ii is very nice to meet you.

If I have difficulty, I will surely ask for your kind help.

This winter vocation is extremely long for China especially for people in my hometown WuHan because of COVID-19.

Hope everything goes well with you.

With best regards.

 

[Alexanov]

Try to get some positive moments from this situation. Use your time!

 

[bingli]

Yes,

My company is in ShangHai, and now I'm working at home in WuHan.

Thanks to the strict measures taken by Chinese government, the disease are now under control. The situation gets better and better, even in my hometown Wuhan.

 

[skycary]

Yes,

My company is in ShangHai, and now I'm working at home in WuHan.

Thanks to the strict measures taken by Chinese government, the disease are now under control. The situation gets better and better, even in my hometown Wuhan.

Your software looks pretty good - is it a small plug-in for self-use or commercial promotion?
I used CAD to export the coordinates of points to Excel, and then used a macro to output NAPA statements. I have done similar things, and the effect is not ideal.
Are you writing in C? Run your KCS and found 2 small problems,
1. Is it more reasonable to use the intersection of CL_F instead of the first point of the first waterline?
2. The flat edge line is not defined. If the flat bottom line is not used, the plane boundary is not limited, but the angle control is done. The flat bottom line should be a tangent point, not a corner point.
Overall it is very good! Of course, I can also help participate in the internal test

 

[bingli]

Your software looks pretty good - is it a small plug-in for self-use or commercial promotion?
I used CAD to export the coordinates of points to Excel, and then used a macro to output NAPA statements. I have done similar things, and the effect is not ideal.
Are you writing in C? Run your KCS and found 2 small problems,
1. Is it more reasonable to use the intersection of CL_F instead of the first point of the first waterline?
2. The flat edge line is not defined. If the flat bottom line is not used, the plane boundary is not limited, but the angle control is done. The flat bottom line should be a tangent point, not a corner point.
Overall it is very good! Of course, I can also help participate in the internal test

Dear skycary,

good day!

Thanks for your good advise!
The function of generating NAPA macro is a newly developed function of our hull lines design and optimization software.
For your inquiries, I would like to reply as below:

1. Is it more reasonable to use the intersection of CL_F instead of the first point of the first waterline?

Re:
Of course, we should try to use intersection as much as possible.
I checked the macro file, normally most of the waterlines are starting from the definition of intersection point.
-----------------------
Below is the Z=1 waterline, as u can see.
CUR WLA_1; Z 1
XY * CL_A, -/, (-104.9487,0.3982), FR_1, FR_1.5, FR_2, FR_2.5, FR_3,
FR_3.5, FR_4, FR_4.5, FR_5, FR_6, FR_7, FR_8, FR_9, FRM

-----------------------
And Even for Z=0, we use the intersection point
CUR FB_A; Z 0
XY * CL_A/X=#-99.573, -/, (-99.573,0.0816), /-, (-97.75,0.099),
(-92,0.4349), (-86.25,0.9207), (-80.5,1.4631), (-74.75,2.095),
(-69,2.7977), (-63.25,3.576), (-57.5,4.4998), (-46,7.014),
(-34.5,9.7382), (-23,11.728), (-11.5,12.5908), FRM/Y=#12.3769


2. The flat edge line is not defined. If the flat bottom line is not used, the plane boundary is not limited, but the angle control is done. The flat bottom line should be a tangent point, not a corner point.
Overall it is very good! Of course, I can also help participate in the internal test[/QUOTE]

Re:
For the flat side line:
To my understanding, NAPA use grids to represent each patch, when we have sufficient suitable grids, we can define a ship perfectly.
we have station lines, water lines and buttock lines and the refined patch grids, we can describe a ship with sufficient accuracy.
Another thing, Flat side line in our software is not so smooth, and sometimes could complicate the hull description.
For the above reasoms, we do not use Flat side line is the hull description.

For the flat bottom line:
Not all the boundary condition for flat bottom are tangent, we use point with angle condition to describe the boundary and It suitable for much more conditions.
Our software is base on BSpline and can get the angle condition easily.

-----------------------
Below is the FR=1 station line, as u can see, we use point with angle condition to describe.
CUR FR_1; X -103.5
YZ * CL_A/Z=#0.4224, /-, (0.9292,1), (1.3796,2), (1.129,4),
(0.5184,6), (0.8101,8), (2.743,9), (4.1149,9.2422), (5.9927,9.5094),
(9.2199,10), (12.2512,10.5798), (13.535,11), (15.0759,12),
(16.0682,14), 90/, (16.1,14.4257), (16.1,16), DKA_1

At present this software is for internal use and can only provide some modeling, optimization service if you are in need and interested.