Strange line appear when export to kmz

[namlt33]

As i  mentioned, there are some strange line appear when i export this particular polyline to kmz. I had attach the dwg contained the polyline that cause the problem. I dont know why it behave like this, how can i fix this?

[Pointdump]

Hi @namlt33,
I'm guessing the problem is your custom coordinate system. I wasn't able to export to KMZ, or even use Bing Live Maps. I get "No geographic location defined."
Dave

[namlt33]

https://drive.google.com/drive/folders/16x2tnmYDObc1pfm6QXuTvLL_0TMkKE50?usp=drive_link
Here is my custom coordinate system files, pls take a look and let me know if you can export the kmz

[Pointdump]

Hi @namlt33,
Your Google Drive requires permission, so I wasn't able to get those files.

Edit: Thanks. Got them.
I'm not able to create a KMZ from your drawing.
Have you searched EPSG for coordinate system definitions?
https://epsg.io/?q=Vietnam
Dave

[Pointdump]

@namlt33,
Civil 3D already has the Vietnam2000 Datum and a Vietnam2000-to-WGS84 Geodetic Transformation.
Dave

[igi_pop]

Hey!

I've managed to transform it, but i'm unsure if the location is dead on.

Can you make a pin on google earth or maps, and share it, so i can see where it's supposed to start or end?

Cheers,

Iggy

edit:

Actualy, here's the KMZ and let us know if it's fine 🙂

[ChicagoLooper]

Hi @namlt33 

You custom coordinate system is the problem.

Would it possible to put your line in a known coordinate system, not a custom one, then upload it?

Also, your uploaded drawing doesn't look reliable due to your 'custom' coordinate system. Any efforts to transform your drawing will likely give bad results because the transformation will continue using that bad projection. Your issue could be x,y coordinates. You might have flip-flopped them, treating the X as though it were Y and the Y as X.

Did your original drawing use Geographic Coordinates with Lat/Long degrees? Or did it use Projected Coordinates with meters? Whether your original data uses degrees or meters may help in resolving your issue.

It's best to put your original drawing in an established, known coordinate system for your area (the country of your site). Once it's in good drawing environment, your geospatial parameters can be used to create a new custom coordinate system.

[Pointdump]

Hi Iggy,
At least you got the right country. Area of Interest is in Laos, approximately Lat:16.569074,Long:105.960217.

@namlt33,
There's a problem with coordinates in your drawing, highly negative X's.
Dave

[igi_pop]

Thanks.

I've noticed the coords, but who knows what they might be doing, or how.

For example, not using the neighbouring country system, but drawing "from their own".

Hope the OP returns with aditional info.

Iggy

[ChicagoLooper]

@namlt33 

Xe Champhone Wetlands. Is that correct?

Assuming you have a Georeferenced Drawing to begin with, you may export your line to KMZ format. It doesn't matter what projection your georeferenced drawing is currently using, just make sure it has a VALID ONE. Also, don't assign a 'Custom Coordinate System,' assign one that's known, one that's already established, published, and used in GIS capable programs, such as Arc Pro, QGIS, Global Mapper, AutoCAD Map3D, Civil3D. etc., etc.

During your export to KMZ, make sure you give the export WGS84, Lat-Long Degrees, also referred to as LL84, EPSG 4326. By doing it this way, AutoCAD will TRANSFORM from your 'current' modelspace CS to the manually assigned LL84.

You may then import this KMZ line into a NEW drawing. You may assign any proper CS to this new drawing. Make sure you honor the KMZ's native coordinate system, which is LL84 EPSG 4326, so AutoCAD can transform from the KMZ's native CS to your current drawing's CS.

If done correctly, you may also view your KMZ in Google Earth Pro.

[namlt33]

Hi everyone, my location is South of Viet Nam (Vung Tau City). Anyway i figure it out that the System coordinate is not the issue but the nature of the polyline it self. I have try to export it in other coordinate systems and the result get very similar to the image @Pointdump had attach. Some part of the polyline is made of an arc and those  will create a long line when exporting to kmz

[igi_pop]

Hey!

But I've managed to export the whole thing, and attached the kmz to the forum post. Did you check it out?

It's not funky, looks just like in the dwg.

Iggy

[namlt33]

Am little confused, so you too witness the same problem but you have the transform method to "fix" the polyline or you can export it normally from the 1st place?

[igi_pop]

It did not work from the start.

1. with the provided coord sys it came out on the south pole or something

2. the polyline had properties like "global width", and that's also an issue.

3. so, i "cleaned it up", no segments were deleted or converted, assigned the Vietnam lat long coord sys, and presto.

One thing to bare in mind, it turnes out as a multipart geometry, inside a foder inside a folder. So you gotta dig to the "model folder" (that's google earth i'm talking about), and move only the polyline to "your places". Group it into a "folde

r" and assign a style that you like. eg, thick red line.

That's my kmz result a few post earlier.

Cheers,

Iggy

(my kid cut my response short 😁)

[Pointdump]

Iggy,
Your KMZ file is nowhere near Vung Tau City.
"3. so, i 'cleaned it up', no segments were deleted or converted, assigned the Vietnam lat long coord sys, and presto."
I'd sure like to see some screen shots of what you did, and what exactly coordinate system you assigned. No coordinate system I found can deal with the large negative X coords.
Dave

[Pointdump]

@namlt33,
This is the Area of Interest?
Dave

[igi_pop]

well, that's why we needed more info. the original request was about strange lines. So, here's a kmz with no strange lines 🙂

Wee all saw the coords, and presumed they are wrong. But that doesn't stop us from creating a kmz from it.

Iggy

[Pointdump]

Iggy,
"We all saw the coords, and presumed they are wrong. But that doesn't stop us from creating a kmz from it."
The closest "official" coordinate system to Nam's custom CRS that I could find, EPSG:5899, puts that polyline in Sumatra. So why isn't your KMZ in Sumatra?
Dave

[igi_pop]

Hey!

If you check my posts, at no point did i say that things are correct. Just that i managed to create a clean kmz with no strange lines, andd was waiting on more info on the location to see if the community can do anything about it.

[ChicagoLooper]

@namlt33 wrote

<<Anyway i figure it out that the System coordinate is not the issue….>

You don’t need to assign a projection (don’t need to create a custom one either) if the geospatial location is not important to you.