I have built several domains and problems in PDDL and now I'm looking for a possibilty to visualize my domains, problems and solutions. My questions are as follows:

* Are there any tools for a rather simple graphical representation of plans (e.g. nodes and connections)?
* Are there tools that can display the current world state of my domain at any time (i.e. the value of all variables in my domain, after each step in my plan) in plain text?
* How do I integrate PDDL in the system architecture? If I want to use a 2D or 3D representation of my world (e.g. Gazebo) how can i "connect" Gazebo and PDDL?

Thanks!