From 4b24579070e9d33044ef9cefbb05e2e2ac117136 Mon Sep 17 00:00:00 2001
From: Kazhnuz <kazhnuz@chlore.net>
Date: Sun, 8 Sep 2019 16:23:30 +0200
Subject: [PATCH] feat(scenes): handle scene transitions

---
 gamecore/modules/scenes.lua |  5 ++--
 gamecore/scenemanager.lua   | 55 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/gamecore/modules/scenes.lua b/gamecore/modules/scenes.lua
index 3484df6..c615f6f 100644
--- a/gamecore/modules/scenes.lua
+++ b/gamecore/modules/scenes.lua
@@ -43,6 +43,7 @@ function Scene:new()
   self.inputLocked      = true
   self.inputLockedTimer = 2
   self:flushKeys()
+  self.isActive = false
 
   self:initWorld()
 
@@ -136,7 +137,7 @@ end
 -- Handle inputs from keyboard/controllers
 
 function Scene:setKeys()
-  if (self.inputLocked) then
+  if (self.inputLocked) or (not self.isActive) then
     self.inputLockedTimer = self.inputLockedTimer - 1
     if (self.inputLockedTimer <= 0 ) then
       self.inputLocked = false
@@ -154,7 +155,7 @@ function Scene:getKeys(sourceid)
   end
 
   local sourceid = sourceid or 1
-  if (self.inputLocked) then
+  if (self.inputLocked) or (not self.isActive) then
     core.debug:print("scene", "inputs are currently locked")
     return core.input.fakekeys
   else
diff --git a/gamecore/scenemanager.lua b/gamecore/scenemanager.lua
index b1a8af6..69e4878 100644
--- a/gamecore/scenemanager.lua
+++ b/gamecore/scenemanager.lua
@@ -30,13 +30,21 @@ local SceneManager  = Object:extend()
 
 function SceneManager:new(controller)
   self.controller   = controller
+  self.timers       = self.controller.modules.Timers(self)
   self.currentScene = nil
 
   self.storage      = {}
+
+  self:initTransitions()
 end
 
 function SceneManager:setScene(scene)
-  self.currentScene = scene
+  if self.transition.isPrepared then
+    self:startTransition(scene)
+  else
+    self.currentScene = scene
+    self.currentScene.isActive = true
+  end
 end
 
 function SceneManager:storeCurrentScene(name)
@@ -63,6 +71,7 @@ end
 -- Update the current scene and its subobjects
 
 function SceneManager:update(dt)
+  self.timers:update(dt)
   if (self.currentScene ~= nil) then
     self.currentScene:updateStart(dt)
     self.currentScene:setKeys()
@@ -104,6 +113,50 @@ function SceneManager:keyreleased( key )
   self.currentScene:keyreleased( key )
 end
 
+-- TRANSITION FUNCTIONS
+-- Prepare transitionning to the next scene
+
+function SceneManager:initTransitions()
+  self.transition = {}
+
+  self.transition.easeIn      = "inQuad"
+  self.transition.easeOut     = "outQuad"
+  self.transition.duration    = 1
+
+  self.transition.nextScene   = nil
+  self.transition.isPrepared  = false
+end
+
+function SceneManager:prepareTransition(duration, easeIn, easeOut)
+  self.transition.easeIn      = easeIn    or self.transition.easeIn
+  self.transition.easeOut     = easeOut   or self.transition.easeOut
+  self.transition.duration    = duration  or self.transition.duration
+
+  self.transition.isPrepared  = true
+end
+
+function SceneManager:startTransition(nextScene)
+  self.transition.nextScene = nextScene
+  self.currentScene:flushKeys(self.transition.duration)
+  self.currentScene.isActive = false
+  self.transition.nextScene.isActive = false
+  core.screen:fadeIn(self.transition.duration / 2.5, self.transition.easeIn)
+  self.timers:newTimer(self.transition.duration / 2, "fadeOut")
+end
+
+function SceneManager:timerResponse(timer)
+  if timer == "fadeOut" then
+    self.currentScene = self.transition.nextScene
+    self.currentScene:flushKeys(self.transition.duration / 2.5)
+    self.currentScene.isActive = false
+    core.screen:fadeOut(self.transition.duration / 2.5, self.transition.easeOut)
+    self.transition.isPrepared = false
+    self.timers:newTimer(self.transition.duration / 2.5, "activateScene")
+  elseif timer == 'activateScene' then
+    self.currentScene.isActive = true
+  end
+end
+
 -- DRAW FUNCTIONS
 -- Draw the current scene