Add distortion to camera sensors

[peci1]

Desired behavior

SDF tags <distortion> in camera sensors should be respected.

Alternatives considered

Implementation suggestion

As of now, they are silently ignored. I think until distortion is supported, it might be valuable to at least issue a warning that the distortion is not taken into account. It is then also wrong to publish the distortion read from SDF as camera info, as the actual distortion is zero.

Additional context

This should also appear in the comparison chart between Gazebo Classic and Ignition Gazebo.

[chapulina]

Here's Gazebo classic's Camera Distortion tutorial as another reference.

[scpeters]

much of the implementation of camera distortion in gazebo classic is in the rendering library:

• https://github.com/osrf/gazebo/blob/gazebo11/gazebo/rendering/Distortion.hh

I imagine that when porting to ignition, we will similarly put some of that functionality in ign-rendering?

[iche033]

I imagine that when porting to ignition, we will similarly put some of that functionality in ign-rendering?

+1

[iche033]

We can start by porting Gazebo classic's Distortion class over to the ogre 1.x implementation in ign-rendering.

In ign-rendering, we can apply distortion to cameras using a similar approach as applying noise. The idea is to apply distortion as a render pass, see example for applying noise.

We'll need the add the abstract / base Distortion classes, see GaussianNoisePass.hh and BaseGaussianNoisePass.hh.

Then put the actual ogre 1.x implementation in ogre directory, see OgreGaussianNoise.cc and OgreGaussianNoise.hh

There is a macro to register the render pass so that it can be created by the RenderPassSystem

[peci1]

gazebosim/gz-rendering#502 has brought the required ign-rendering support.

[iche033]

#192

[WilliamLewww]

Closed with the following merges:

• Distortion Camera Sensor #192
• Distortion camera integration test gz-sim#1374