A few changes for 0.9.1

[nsubiron]

Description

Massive PR with lots of changes required for 0.9.1.

User-side improvements

• New map Town03, now set as default map.
• Support for Python 3 on Linux.
• Add "dynamic_weather.py" script that changes the weather in real-time.
• More improvements to "manual_control.py", support for changing weather, the camera view, and the vehicle.
• Add an option to command-line to change quality level when launching the simulator.

API changes

• API methods for retrieving and changing weather conditions and lighting, world.get_weather() and world.set_weather(params). Add carla.WeatherParametes class that parametrizes the weather conditions, and add weather presets to it: carla.WeatherParametes.ClearNoon, etc.

• Remove client.ping(), client.get_server_version() accomplishes the same.

• Add support for requesting the list of actors alive in the current world, world.get_actors(). Returns an ActorList object, behaves like a list but has filter functionality and lazy initialization of Actors.

• Add id (id of current episode) and map name to carla.World class

• Rename contains_X() methods to has_X().

• Add semantic_tags to Actors containing the list of tags of all of its components (these tags match the tags retrieved by the semantic segmentation sensor).

• Add a "tick" message containing info of all the actors in the scene, this is executed in the background and cached. This way calls to actor.get_transform() or actor.get_location() do not need to connect with the simulator, but can access the cached info. This makes these calls quite cheap.

• Add world.wait_for_tick() and world.on_tick(callback) methods for synchronizing the client with simulator updates. Both methods return/pass a carla.Timestamp object containing, frame count, delta time of last tick, global simulation time, and OS timestamp.

• Add actor.get_velocity() and actor.get_acceleration(), these are also cached so its quite cheap to get them.

• Add bounding boxes to vehicles, vehicle.bounding_box property.

• Function to enable/disable simulating physics on an actor, actor.set_simulate_physics(enabled=True).

• Expose traffic lights and signs as actors. Traffic lights have a specialized actor class that has the traffic light state (red, green, yellow) as property.

• Add methods for accessing and modifying individual items in carla.Image (pixels) and carla.LidarMeasurement (locations).

• Add collision event sensor, "sensor.other.collision", that triggers a callback on each collision to the actor it is attached to. The callback receives a carla.CollisionEvent containing the actor it collided to and the normal impulse of the collision.

• Add carla.Vector3D to generalize carla.Location.

Other C++ improvements

• Add multi-streams for streaming simultaneously to multiple clients (used by the "tick" message).
• Refactor of client-side code:
  • Add Simulator class shared by all the API objects that decides whether to call the server or retrieve a cached value. Leave detail::Client for pure networking operations only.
  • Add concept of episode to facilitate restarting episodes and changing map in the future.
  • Add EpisodeProxy that allows access to Simulator only if the episode hasn't changed.
  • More geom classes, geom::Vector3D and geom::BoundingBox.
  • More synchronization classes, AtomicSharedPtr, RecurrentSharedFuture, CallbackList.
  • Add ActorVariant for lazy initialization of Actors.
  • Add CachedActorList for caching Actor descriptions and reduce call to the server.
• Small refactor of quality level related stuff and ported to new game mode.
• Adjust camera gamma to 2.4 (by @TheNihilisticRobot).
• Add MsgPack class and functions to serialize rpc objects into/from Buffer.
• Add AWorldObserver sensor and its serializer for serializing all the actors registered in the episode and sending the "tick" message.
• Add ACollisionSensor and its serializer for detecting collisions.
• Add not_spawnable tag for sensors that cannot be spawned by the client (e.g. world observer).
• Allow vehicles without color attribute, to support vehicles that cannot change its color.
• Archive Python eggs on Jenkins
• Fine grained targets in Makefile, compilation times reduced by compiling only what's necessary.
• Add uncrustify config file for formatting UE4 C++ code.
• Add support for ".gtest" file, each line of this file is passed to GTest executables as arguments when running make check targets. Very handy for filtering test while developing.
• Update Content assets package link, which solves a lot of issues related with the assets.

Fixes

• Fix wildcard filtering issues, now "vehicle.*" or "bmw" patterns work too.
• Fix actor.set_transform() broken for attached actors.
• Fix None is a reserved keyword in Python 3, rename carla.ColorConverter.None to carla.ColorConverter.Raw.
• Workaround for setup.py to link against libcarla_client again (Linux only)
• Fix leaking objects in simulation when despawning a vehicle. Now pawn's controller is destroyed if necessary when destroying an Actor.
• Suppress exceptions in destructors.

Issues that fixes

• Fix Collisions are not annotated when vehicle's speed is low #13 Collisions are not annotated when vehicle's speed is low.
• Fix SplineMeshRepeater loses its collider mesh. #35 SplineMeshRepeater loses its collider mesh.
• Fix Issues with two-wheeled vehicles #496 Issues with two-wheeled vehicles.
• Fix Set the max distance culling for foliage #572 Set the max distance culling for foliage.
• Fix Adjust Pedestrian Animations #576 Adjust pedestrian animations.
• Fix Adjust Vehicle Physics  #577 Adjust vehicle physics.
• Fix Packing on Win / Filenames too long #649 Filenames too long.
• Fix Overflow on platform time-stamp #692 Overflow on platform time-stamp.
• Fix Compiling carla for python 3 #698 Compiling for Python 3.
• Fix Allow controlling the weather from the client-side #749 Allow controlling the weather from the client-side.
• Fix Allow disabling actor physics #822 Allow disabling actor physics.
• Fix Set transform of actor attached to another one should be relative #857 Set transform of actor attached to another one should be relative.

Where has this been tested?

• Platform(s): Ubuntu 16.04
• Python version(s): 2.7 and 3.5
• Unreal Engine version(s): 4.19

Possible Drawbacks

Definitively.

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