Added fade in/out transition

README.md

@@ -162,6 +162,8 @@ The predefined transitions provided by ```monarch.transitions.gui``` are:
 * ```slide_out_bottom```
 * ```scale_in```
 * ```scale_out```
+* ```fade_in``` - Set node alpha to fully transparent (i.e. 0.0) and fade to fully opaque (i.e. 1.0)
+* ```fade_out``` - Set node alpha to fully opaque (i.e. 1.0) and fade to fully transparent (i.e. 0.0)
 
 Additionally there's functionality to create a full set of transitions for common transition styles:
 
@@ -169,6 +171,7 @@ Additionally there's functionality to create a full set of transitions for commo
 * ```transitions.in_left_out_right(node, duration, [delay], [easing])```
 * ```transitions.in_left_out_left(node, duration, [delay], [easing])```
 * ```transitions.in_right_out_right(node, duration, [delay], [easing])```
+* ```transitions.fade_in_out(node, duration, [delay], [easing])```
 
 **PARAMETERS**
 * ```node``` (node) - Gui node to animate.

example/menu.gui_script

@@ -6,7 +6,7 @@ function init(self)
 
 	gui.set_text(gui.get_node("timestamp"), os.date())
 
-	self.transition = transitions.in_right_out_left(gui.get_node("root"), 0.6, 0)
+	self.transition = transitions.fade_in_out(gui.get_node("root"), 0.6, 0)
 end
 
 function on_input(self, action_id, action)

monarch/transitions/gui.lua

@@ -88,6 +88,22 @@ function M.scale_out(node, from, easing, duration, delay, cb)
 	gui.animate(node, gui.PROP_SCALE, ZERO_SCALE, easing, duration, delay, cb)
 end
 
+function M.fade_out(node, from, easing, duration, delay, cb)
+	local to = gui.get_color(node)
+	to.w = 1
+	gui.set_color(node, to)
+	to.w = 0
+	gui.animate(node, gui.PROP_COLOR, to, easing, duration, delay, cb)
+end
+
+function M.fade_in(node, from, easing, duration, delay, cb)
+	local to = gui.get_color(node)
+	to.w = 0
+	gui.set_color(node, to)
+	to.w = 1
+	gui.animate(node, gui.PROP_COLOR, to, easing, duration, delay, cb)
+end
+
 --- Create a transition for a node
 -- @return Transition instance
 function M.create(node)
@@ -255,4 +271,16 @@ function M.in_left_out_left(node, duration, delay, easing)
 end
 
 
+function M.fade_in_out(node, duration, delay, easing)
+	assert(node, "You must provide a node")
+	assert(duration, "You must provide a duration")
+	easing = easing or easings.QUAD()
+	return M.create(node)
+	.show_in(M.fade_in, easing.OUT, duration, delay or 0)
+	.show_out(M.fade_out, easing.IN, duration, delay or 0)
+	.back_in(M.fade_in, easing.OUT, duration, delay or 0)
+	.back_out(M.fade_out, easing.IN, duration, delay or 0)
+end
+
+
 return M