autoscroll variable speed v1.0

README.md

@@ -9,6 +9,8 @@ A Kanboard plugin that groups board dragging and spacing tweaks, configurable un
   apart and to touch.
 - **Mobile drag handle size** -- enlarge the card drag handle Kanboard shows on mobile so
   it is easy to grab with a finger.
+- **Drag auto-scroll** -- while dragging a card, the board scrolls when the pointer nears a
+  screen edge, so you can reach a column that is off screen (desktop and mobile).
 
 These options were originally part of the ShrinkVertically plugin and moved here so that
 drag/touch behaviour can grow on its own (planned: mobile drag-to-move cards, and a drag
@@ -30,6 +32,12 @@ movement threshold so ending a drag does not open the task) without bloating tha
   is hard to grab. FontAwesome icons are sized by `font-size`, so a single rule scales the
   handle from the `--td-handle-size` CSS variable. It is inert on desktop, where Kanboard
   keeps the handle hidden.
+- **Drag auto-scroll**: a script (`Asset/js/drag-autoscroll.js`) listens for jQuery UI
+  sortable's `sortstart`/`sortstop` (which also fire on touch via Kanboard's bundled Touch
+  Punch) and, while a card drag is active, scrolls `#board-container` when the pointer nears
+  its left/right edge. Speed ramps up smoothly toward the edge. After each scroll step it
+  dispatches a synthetic `mousemove` so jQuery UI moves the drop placeholder onto the newly
+  revealed column. It only acts during an active drag, so it is idle otherwise.
 
 ## Requirements