Add GPU based sample laser sensor to simulate Livox mid360 sensor

[georgflick]

This PR adds the following:

• commits from the main gazebo repo: https://github.com/gazebosim/gazebo-classic to keep our devel-enway up-to-date
• commits from Jacobs PR from the cube Re-implement GpuLaser with cube map to lift vFOV limit gazebosim/gazebo-classic#3205

My changes:

• Added a new protobuf type laserscan_angles, which extends the type laserscan with the azimuth and zenith angles
• To use the sample_sensor, you need to set the parameters:
  • sample_sensor to true
  • sample_size to define the amount of "samples", which are published using the angles in the csv files for each step
  • sample_csv_file to a csv file with the angles for the sample sensor
  • to reduce the gpu load while simulating multiple sensors, the texture image was changed from float32 RGB values to float16 R values. Using only one float16 value per pixel, it is not possible to simulate the intensity. The intensity is then set to a fixed value.

How-To-Test:

• Test together with PR in main repo

[Roboterbastler]

Wouldn't it make sense to make it a general option to disable the intensity configuration? The motivation is purely performance related right?
Maybe it would also be beneficial for other (non-sample) sensors if this could be disabled and we save a lot of computation (time). I think we don't use the intensities much, if we even use them anywhere at all...

[Roboterbastler]

Should we drop the existing commits concerning the cubemap implementation from devel-enway? Maybe it would be much cleaner if the commits in this PR replace those.

[georgflick]

Wouldn't it make sense to make it a general option to disable the intensity configuration? The motivation is purely performance related right? Maybe it would also be beneficial for other (non-sample) sensors if this could be disabled and we save a lot of computation (time). I think we don't use the intensities much, if we even use them anywhere at all...

True, I added a parameter compute_intensity , if that is off the texture is only R_FLOAT16 and intensity is set to the parameter fixed_intensity.

[Roboterbastler]

I tested it again and looks good!

[georgflick]

Because of the merging conflicts, from updating the commits to the newest version 11.2.0 from the upstream gazebo-classic repo, I will push the gazebo11 PR branch manually to devel-enway and merge the PR afterwards.