feat: scrolling

lua/api/features/screen/tree.lua

@@ -85,6 +85,22 @@ function tree.hit(root, x, y) end
 ---@return integer h
 function tree.getRect(id) end
 
+---Pans a scrollable node's children, clamped to the content. The node is marked dirty, so the next draw repaints it.
+---@param id NodeId
+---@param x integer
+---@param y integer
+function tree.setScroll(id, x, y) end
+
+---Returns a scrollable node's current offset, or zeroes.
+---@param id NodeId
+---@return integer x, integer y
+function tree.getScroll(id) end
+
+---Returns how far each axis can pan before the content's far edge reaches the box. Zero on an axis whose content fits.
+---@param id NodeId
+---@return integer maxX, integer maxY
+function tree.getScrollRange(id) end
+
 ---Replaces a node's text and marks it for repaint.
 ---@param id NodeId
 ---@param text string
@@ -138,8 +154,8 @@ function tree.getFocus() end
 ---@return NodeId? focused Current focus when no candidate exists.
 function tree.moveFocus(root, direction) end
 
----Registers the painter every custom node calls.
----@param painter fun(id: NodeId, x: integer, y: integer, w: integer, h: integer)
+---Registers the painter every custom node calls. The clip arguments are the region of the node being painted now -- one band of a composited repaint -- so a painter can cull to it instead of redrawing itself once per band.
+---@param painter fun(id: NodeId, x: integer, y: integer, w: integer, h: integer, clipX: integer, clipY: integer, clipW: integer, clipH: integer)
 function tree.setPainter(painter) end
 
 ---Paints dirty nodes; the firmware owns publication to the physical display.