Was using classes to define tools, however this makes it awkward to
dynamically generate them (we can do it, but its not very "Pythonic").
Move to a named tuple.
Having single & multi-column checks inline were becoming unmanageable.
Use a generator to define the layout,
allows for easily adding different layouts in the future.
The problem is that some local path is always returned by
bpy_resource_path. The function does not enforce a check for existence
of the path in the low level code.
Since client code may indeed not care about existence of the directory,
I leave bpy_resource_path alone and patch the python code to check for
existence. An extra argument that enforces the check might be a better
solution, but I will be leaving this to the UI team.
Originally it was nice to have a small list of definitions
with tools inline.
However we need to be able to define drawing functions for tools
which Python can't easily inline.
Use function for keymap definition,
support creating a function from a tuple as well
(handy for simple key-maps).
Active tool name needed to be unique from all other tools.
This caused problems since different modes have different tools with the
same name (Armature/Mesh click to extrude for eg).
Tool names now only need to be unique per mode.
The tool-system it's self is primitive and may be changed.
Adding to 2.8 to develop operators and manipulators as tools.
Currently this is exposed in the toolbar, collapsed by default.
Work-flow remains unchanged if you don't change the active tool.
Placing the 3D cursor is now a Click instead of a Press event,
this allows tweak events to be mapped to tools such as border select,
keeping click for 3D cursor placement when selection tools are set.
