pothi.love/0030-update_editor_box

update_editor_box = function(node, preserve_screen_top_of_cursor_node)
	if node.editor == nil then return end
	-- Compute screen_top1 in viewport coordinates because the editor's font takes scaling into account.
	if vy(node.y) > 0 then
		if not preserve_screen_top_of_cursor_node or node ~= Cursor_node then
			node.editor.screen_top1.line = 1
			node.editor.screen_top1.pos = 1
		end
		node.editor.top = vy(node.y)
	else
		node.editor.screen_top1, node.editor.top = schema1_of_y(node.editor, -vy(node.y))
	end
	node.editor.left = math.floor(vx(node.x)) + Line_number_width*App.width('m')
	node.editor.right = math.ceil(vx(node.x+node.w))
	node.editor.width = node.editor.right - node.editor.left
end