New strategy isolates all draw/don't draw decisions to the ViewGetLOD
routines, and all dimmed/not dimmed to PCB_RENDER_SETTINGS::GetColor.
The actual drawing in PCB_PAINTER is more-or-less conditon free.
Also adds new layers for pad and via hole walls so that they can be
controlled for high-contrast mode.
Also changes the drawing paradigm so that the pads are drawn even when
not on the high contrast layer, just in low contrast. The hole wall
is drawn in high contrast. This actually makes things clearer to the
user (although to be honest was done to keep from having to re-render
pads when the high contrast layer changes since we have two separate
layers now that we can adjut colours on).
Fixes https://gitlab.com/kicad/code/kicad/issues/7328
The problem with simple deleting VIEW_ITEM_DATA upon VIEW_ITEM removal was
caused by the default copy constructors that copied pointers.
Once a copy of an item was destroyed, the VIEW_ITEM_DATA has been
destroyed, effectively invalidating m_viewPrivData for the other item.
- Finalize transition to BOARD_COMMIT (removed all remaining uses of PICKED_ITEMS_LIST) and implicit view/ratsnest updates
- Simplified SELECTION class, it now can be directly added to a VIEW
- Removed unnecesary casts and templates
- Introduced C++11 features (range based for, lambdas) where they improve code readability
- Added non-undoable COMMITs, which can be used to propagate change notifications to interested listeners (e.g. ratsnest/view)