WIP! Python bindings

[tiesus]

A first draft to add python bindings for open3d_conversions using pybind11.
Needs tests and a setup.py to install the code. Currently it's only usable after import through ctypes.

[nkhedekar]

Great initiative @tiesus !
(Converting it to a draft while its a WIP)

[tiesus]

@nkhedekar I'm sorry, really struggling with the bindings. My problem is, that the pybind code compiles, but if I use it in my own pipeline, I get the runtime error, that the whole pointcloud msg is printed to the console. I receive the following output, when i try to use the python binding for void rosToOpen3d(const sensor_msgs::PointCloud2ConstPtr& ros_pc2, open3d::geometry::PointCloud& o3d_pc, bool skip_colors)
....90, 161, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 148, 156, 179, 65, 118, 148, 148, 191, 36, 11, 199, 191, 0, 0, 128, 63, 60, 81, 129, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 140, 188, 179, 65, 75, 58, 202, 191, 22, 244, 198, 191, 0, 0, 128, 63, 75, 97, 67, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 163, 143, 183, 65, 78, 88, 149, 191, 31, 156, 198, 191, 0, 0, 128, 63, 183, 145, 137, 63, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 132, 220, 182, 65, 60, 24, 1, 191, 248, 70, 198, 191, 0, 0, 128, 63, 6, 126, 155, 61, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 80, 188, 181, 65, 224, 37, 250, 189, 216, 54, 198, 191, 0, 0, 128, 63, 100, 112, 162, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 72, 209, 181, 65, 32, 100, 36, 191, 82, 30, 198, 191, 0, 0, 128, 63, 236, 182, 66, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 229, 182, 65, 64, 82, 83, 189, 208, 2, 198, 191, 0, 0, 128, 63, 135, 15, 130, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127, 240, 183, 65, 21, 161, 171, 191, 204, 241, 197, 191, 0, 0, 128, 63, 18, 75, 133, 63, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 42, 208, 181, 65, 76, 230, 234, 191, 121, 234, 197, 191, 0, 0, 128, 63, 5, 157, 128, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 239, 81, 180, 65, 240, 13, 46, 190, 244, 212, 197, 191, 0, 0, 128, 63, 242, 111, 130, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 195, 5, 183, 65, 134, 85, 183, 191, 12, 101, 197, 191, 0, 0, 128, 63, 23, 177, 129, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] is_dense: True, PointCloud with 0 points., False Did you forget to #include <pybind11/stl.h>? Or <pybind11/complex.h>, <pybind11/functional.h>, <pybind11/chrono.h>, etc. Some automatic conversions are optional and require extra headers to be included when compiling your pybind11 module.

I think I'm misssing some headers, probably
sensor_msgs/point_cloud2_iterator.h but I'm new to pybind11 and don't know how to fix the error.