Implemented Yoshi's Island-style flapping (based on Wansti's code) and force-activate...

[supertux.git] / src / object / ambient_sound.cpp

diff --git a/src/object/ambient_sound.cpp b/src/object/ambient_sound.cpp
index e50e946..bec0d9c 100644 (file)
--- a/src/object/ambient_sound.cpp
+++ b/src/object/ambient_sound.cpp
@@ -30,26 +30,48 @@ AmbientSound::AmbientSound(const lisp::Lisp& lisp)
 
   position.x=0;
   position.y=0;
+
+  dimension.x=0;
+  dimension.y=0;
+
   distance_factor=0;
   distance_bias=0;
+  maximumvolume=1;
   sample="";
 
   if (!(lisp.get("x", position.x)&&lisp.get("y", position.y))) {
     std::cerr << "No Position in ambient_sound"  << std::endl;
   }
+
+  lisp.get("width" , dimension.x);
+  lisp.get("height", dimension.y);
+
   lisp.get("distance_factor",distance_factor);
   lisp.get("distance_bias"  ,distance_bias  );
   lisp.get("sample"         ,sample         );
+  lisp.get("volume"         ,maximumvolume  );
+
+  // square all distances (saves us a sqrt later)
+
+  distance_bias*=distance_bias;
+  distance_factor*=distance_factor;
+
+  // set default silence_distance
 
   if (distance_factor == 0)
     silence_distance = 10e99;
   else
-    silence_distance = distance_factor*10e2;
+    silence_distance = 1/distance_factor;
+  
+  lisp.get("silence_distance",silence_distance);
 
-  playing=0;
-  startPlaying();
+  playing=-1; // not playing at the beginning
+  latency=0;
 }
 
+AmbientSound::~AmbientSound() {
+  stop_playing();
+}
 
 void
 AmbientSound::hit(Player& )
@@ -57,7 +79,15 @@ AmbientSound::hit(Player& )
 }
 
 void
-AmbientSound::startPlaying()
+AmbientSound::stop_playing() {
+  if (playing>=0) {
+    Mix_HaltChannel(playing);
+    playing=-1;
+  }
+}
+
+void
+AmbientSound::start_playing()
 {
   playing=sound_manager->play_sound(sample,-1);
   Mix_Volume(playing,0);
@@ -65,24 +95,70 @@ AmbientSound::startPlaying()
 }
 
 void
-AmbientSound::action(float) 
+AmbientSound::update(float deltat) 
 {
-  float dx=Sector::current()->player->get_pos().x-position.x;
-  float dy=Sector::current()->player->get_pos().y-position.y;
-  float distance=sqrt(dx*dx+dy*dy);
+  if (latency--<=0) {
+
+    float px,py;
+    float rx,ry;
+
+    // Player position
+
+    px=Sector::current()->player->get_pos().x;
+    py=Sector::current()->player->get_pos().y;
+
+    // Relate to which point in the area
+
+    rx=px<position.x?position.x:
+      (px<position.x+dimension.x?px:position.x+dimension.x);
+    ry=py<position.y?position.y:
+      (py<position.y+dimension.y?py:position.y+dimension.y);
+
+    // calculate square of distance
+
+    float sqrdistance=(px-rx)*(px-rx)+(py-ry)*(py-ry);
+    
+    sqrdistance-=distance_bias;
+
+    // inside the bias: full volume (distance 0)
+    
+    if (sqrdistance<0)
+      sqrdistance=0;
+    
+    // calculate target volume - will never become 0
+
+    targetvolume=1/(1+sqrdistance*distance_factor);
+
+    float rise=targetvolume/currentvolume;
+
+    // rise/fall half life?
+
+    currentvolume*=pow(rise,deltat*10);
+    currentvolume += 1e-6; // volume is at least 1e-6 (0 would never rise)
+
+    if (playing>=0) {
 
-  distance-=distance_bias;
+      // set the volume
+      Mix_Volume(playing,(int)(currentvolume*maximumvolume*MIX_MAX_VOLUME));
 
-  if (distance<0)
-    distance=0;
+      if (sqrdistance>=silence_distance && currentvolume<1e-3)
+       stop_playing();
+      latency=0;
+    } else {
+      if (sqrdistance<silence_distance) {
+       start_playing();
+       latency=0;
+      }
+      else // set a reasonable latency
+       latency=(int)(0.001/distance_factor);
+      //(int)(10*((sqrdistance-silence_distance)/silence_distance));
+    }
+  } 
 
-  targetvolume=1/(1+distance*distance_factor);
-  float rise=targetvolume/currentvolume;
-  currentvolume*=pow(rise,.05);
-  currentvolume += 1e-30;
-  //  std::cout << currentvolume << " " << targetvolume << std::endl;
-  Mix_Volume(playing,(int)(currentvolume*MIX_MAX_VOLUME));
+  // heuristically measured "good" latency maximum
 
+  //  if (latency>0.001/distance_factor)
+  // latency=
 }
 
 void