Add simple swipe component

druid/base/hover.lua

@@ -70,7 +70,7 @@ function M.set_hover(self, state)
 end
 
 
---- Strict button click area. Useful for
+--- Strict hover click area. Useful for
 -- no click events outside stencil node
 -- @function hover:set_click_zone
 -- @tparam node zone Gui node

druid/base/swipe.lua

@@ -0,0 +1,129 @@
+--- Component to handle swipe gestures on node.
+-- Swipe will be triggered, if swipe was started and
+-- ended on one node
+-- @module druid.swipe
+
+--- Component events
+-- @table Events
+-- @tfield druid_event on_swipe Trigger on swipe event
+
+--- Component style params
+-- @table Style
+-- @tfield number SWIPE_TIME Maximum time for swipe trigger
+-- @tfield number SWIPE_THRESHOLD Minimum distance for swipe trigger
+-- @tfield bool SWIPE_TRIGGER_ON_MOVE If true, trigger on swipe moving, not only release action
+
+local Event = require("druid.event")
+local const = require("druid.const")
+local helper = require("druid.helper")
+local component = require("druid.component")
+
+local M = component.create("swipe", { const.ON_INPUT })
+
+
+local function start_swipe(self, action)
+	self._swipe_start_time = socket.gettime()
+	self.start_pos.x = action.x
+	self.start_pos.y = action.y
+end
+
+
+local function reset_swipe(self, action)
+	self._swipe_start_time = false
+end
+
+
+local function check_swipe(self, action)
+	local dx = action.x - self.start_pos.x
+	local dy = action.y - self.start_pos.y
+	local dist = helper.distance(self.start_pos.x, self.start_pos.y, action.x, action.y)
+	local delta_time = socket.gettime() - self._swipe_start_time
+	local is_swipe = self.style.SWIPE_THRESHOLD <= dist and delta_time <= self.style.SWIPE_TIME
+
+	if is_swipe then
+		local is_x_swipe = math.abs(dx) >= math.abs(dy)
+		local swipe_side = false
+		if is_x_swipe and dx > 0 then
+			swipe_side = const.SWIPE.RIGHT
+		end
+		if is_x_swipe and dx < 0 then
+			swipe_side = const.SWIPE.LEFT
+		end
+		if not is_x_swipe and dy > 0 then
+			swipe_side = const.SWIPE.UP
+		end
+		if not is_x_swipe and dy < 0 then
+			swipe_side = const.SWIPE.DOWN
+		end
+
+		self.on_swipe:trigger(self:get_context(), swipe_side, dist, delta_time)
+		reset_swipe(self)
+	end
+end
+
+
+--- Component init function
+-- @function swipe:init
+-- @tparam node node Gui node
+-- @tparam function on_swipe_callback Swipe callback for on_swipe_end event
+function M.init(self, node, on_swipe_callback)
+	self.style = self:get_style()
+	self._trigger_on_move = self.style.SWIPE_TRIGGER_ON_MOVE
+	self.node = self:get_node(node)
+
+	self._swipe_start_time = false
+	self.start_pos = vmath.vector3(0)
+
+	self.click_zone = nil
+	self.on_swipe = Event(on_swipe_callback)
+end
+
+
+function M.on_input(self, action_id, action)
+	if action_id ~= const.ACTION_TOUCH then
+		return
+	end
+
+	if not helper.is_enabled(self.node) then
+		return false
+	end
+
+	local is_pick = gui.pick_node(self.node, action.x, action.y)
+	if self.click_zone then
+		is_pick = is_pick and gui.pick_node(self.click_zone, action.x, action.y)
+	end
+
+	if not is_pick then
+		reset_swipe(self, action)
+		return false
+	end
+
+	if self._swipe_start_time and (self._trigger_on_move or action.released) then
+		check_swipe(self, action)
+	end
+
+	if action.pressed then
+		start_swipe(self, action)
+	end
+
+	if action.released then
+		reset_swipe(self, action)
+	end
+end
+
+
+function M.on_input_interrupt(self)
+	reset_swipe(self)
+end
+
+
+--- Strict swipe click area. Useful for
+-- restrict events outside stencil node
+-- @function swipe:set_click_zone
+-- @tparam node zone Gui node
+function M.set_click_zone(self, zone)
+	self.click_zone = self:get_node(zone)
+end
+
+
+return M