Carla: Please explain the lidar's point cloud data format. What does (x, y, z) mean?

[zhangfree2018]

I also want to understand how to get the lane line data information? I viewed the relevant question, but I still don't know how to get it ? Can I get non-player sports direction? Whether the speed currently acquired for a non-player can be understood as a scalar?

[wzhAptiv]

Hi @zhangfree2018 ,
The LiDAR data format is now as:
+x is to the left of the car, +y is to the back of the car, +z is to the ground (downwards).
You can plot the points to somewhere to check it.

For other information, I suggest you firstly read the Measurement you can get from the server, which is documented here

[zhangfree2018]

Hi @wzhAptiv，
If the format is what you said，what is to the right of the car and to the front of the car? I have plotted the points , what does the value of these points mean? As follows is what I plotted some points:
ply
format ascii 1.0
element vertex 15839
property float32 x
property float32 y
property float32 z
end_header
2.38 -1.72 -0.52
2.38 -1.64 -0.51
2.43 -1.61 -0.51
-13.91 42.22 -7.84
-14.06 39.96 -7.47
-14.61 39.01 -7.34
-15.17 38.15 -7.24
-15.74 37.37 -7.15
-16.16 36.32 -7.01
-16.73 35.65 -6.94
-17.21 34.83 -6.85
-17.58 33.85 -6.73
-18.84 34.56 -6.94

[wzhAptiv]

Then I really suggest you to plot those data points in some visualization software (quite a lot can visualize ply files). You'll have much better understanding.
those 'to the direction' means the axis direction it pointing to, please consider in the coordinate system axes.

[marcgpuig]

Hi @zhangfree2018.

The output you have is correct. These points are sensor's local space, so it's up to you to transform the points to world space. Transforming these points be careful with #392.

As @wzhAptiv mentioned, we suggest you to plot these points in some some visualization software like Meshlab.

[zhangfree2018]

Hi @marcgpuig @wzhAptiv ,
Thanks for your explanation!