Importing GCPs in local CS rotated/tilted model

Development Asset Creation
1

Hi,

Registration/Alignment was done using images gps. After that I disabled images gps by setting priors to unknown and importing 4 GCPs in local cs/euclidean. But after running alignment model was rotated. There are no deviations and here is info panel screenshot.

image
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Questions are:
Why is this happening?

Will using “set ground plane” or tranformation during export change theese coordinates, because I need them to stay as they are but without model being almost upside down?
Reason - this model will be used together with CAD version in same view/scene.

2

Hi Rango

What is the orientation of your local coordinate system? In RealityScan X goes to right/east and Y up/north. It is possible that your system uses other orientation? Are all GCPs placed properly? What will happen when you won’t use georeferencing data for the first alignment?
Are the centre coordinates of the reconstruction region valid for your measured area?

Using Set ground plane or transformation can change the exported coordinate values. But it also depends on your export settings.

3

I just received screenshots of cad/bim model with written xyz for 4 points on 4 corners of the ship. Logic of those coordinates and cad displays that x follows longer axis of the ship, y is width and z i up, aplying that tilts the model. But, after I switched/flipped x and y in GCPs in import I got normal model and orientation. But wrong coordinates of course.

GCPs are place properly. I have not tried with first alignments with georeferencing off since it is 4000 images project, but I will. Centre of the region seems to be fine.

4

According to your description it looks like you are using differently oriented coordinate system.
The one used in RealityScan is right-handed, yours is probably left-handed. In that case it is possible that you’ll need to use negative coordinates, which will represent the proper results for you with just a negative value.

What do you mean by: But wrong coordinates of course. ? Are the coordinates totally off?

5

Hi, thanks for quick reply. I am not sure if they are using differently oriented system, which I will clarify. But here are the coordinates that I received:
Name,YNorth,XEast,Alt
P1,23.419,15.981,65.363
P2,-13.5,5.565,58.924
P3,25.02,13.289,61.498
P4,22.309,328.202,37.65
P5,11.312,339.649,46.45
P6,6.588,338.098,31.8

Which axiss should be inverted (negative)?

6

Also, you mentioned here that RC is using left hand orientation, but here in this post you said otherwise Orientation of coordinate system in RC - #6 by AgnieszkaSojka1

7

Yeah, that was my mistake. It is right-handed.

8

It is hard to say just from the coordinates, but according to the header the coordinates should be in right-hand coordinate system.

9

Here is screenshot I received.

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image1065×673 306 KB

10

I just received answer that they are using X as North and Y as East.

11

In that case just make negative coordinates from positive ones and vice versa.
Also, X will be Y for you.