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Hello,

I would like to report a problem during importing 2dm mesh in BlueKenue.

The problem is that BlueKenue is distorting my mesh in high resolution areas as it is indicated in annexed figure.



I annexed my 2dm mesh file for your evaluation






I will appreciate any help.

Regards

Hi
This is not a problem of Blue Kenue itself, and it has been already reported in this forum.
the problem comes from the rounding of your coordinates which are simple Real number (So something like 7 significant numbers)

Move your mesh to have some local coordinates and this problem will disappear.

Regards

To elaborate on Christophes email.

1. Select the "original_mesh" object in the WorkSpace.
2. Select menu item "Edit->Shift in X/Y"
3. Enter -500000 for X shift and -8400000 for Y shift.

Cheers... Martin

Thank you all for the help.

Serrer's solution solved my problem, but I lost the original coordinates of mesh file.

Is it possible to restore the original coordinates without mesh deformation?

Could I define some kind of local coordinates directly in 2dm file before Blue Kenue importing?


Regards

You can shift the mesh back to the original coordinates at any time.

Please note: the mesh isn't actually deformed. Inside Blue Kenue, all data is double precision. The wierdness you see in your mesh is because the OpenGL graphics driver uses single precision coordinates internally and so it's just a display problem.

Cheers... Martin

Yes!

My mesh is running fine with original coordinates.

thank you!

Hi Serren,

I am having the same issue and trying to follow-
1. Select the "original_mesh" object in the WorkSpace.
2. Select menu item "Edit->Shift in X/Y"
What offset values should I put for X and Y here?
Also, should I do the shift after creating the mesh only? Or I can shift the x,y of all the data (bathymetry, outline, and density polygon) before creating mesh?

I don't want to change the real coordinate as I want to see the result on top of a real satellite image later. Here is an example of my density polygon coordinates:

595009.782 4755249.783
595009.1 4755249.722
595008.418 4755249.779
595007.755 4755249.951

BK 3.12.8-alpha will:

1. Importing the mesh will now have the correct colour scale when dragged to a 2D View
2. The BEGPARAMDEF/ENDPARAMDEF section will now be brute force copied as metadata properties of the imported mesh so that you can more easily find them if you wish

As for your question, "What offset values should I put for X and Y?" Well, I'd suggest that you first understand what you are trying to do. The reason for shifting is so that the numbers get smaller. That is, instead of 10.1 and 11.2 you can have 0.1 and 1.2 if you shifted (i.e. subtracted) 10 from both of the numbers. And why do you want to shift numbers? So that the display does not bump up against the 7 digit limit due to single precision floating points.

I'd suggest you try this out with a simple example in order to see for yourself what is going on and whether it meets your needs (or not). Perhaps you could shift your satellite data too if needed? Just a thought...

Kindly,
Alan

Thank you, a.barton.

I tried to shift the X, Y and it worked. But my issue of mine was to keep the real coordinate in order to match with the satellite image. When I am shifting x, y then it again represents a shifted coordinate. One thing I could do, was to shift the satellite image coordinate. But I will want to try first to set the double precision format for the coordinate file. I am not sure if there is any way to set the double precision instead.

Hi don't use the shift functions!
Just define the origin point when you create the selafin file!