src/object/ambient_sound.cpp

   1 // ambient_sound.cpp   basti_
   2 //
   3 //  SuperTux
   4 //
   5 //  This program is free software; you can redistribute it and/or
   6 //  modify it under the terms of the GNU General Public License
   7 //  as published by the Free Software Foundation; either version 2
   8 //  of the License, or (at your option) any later version.
   9 //
  10 //  This program is distributed in the hope that it will be useful,
  11 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 //  GNU General Public License for more details.
  14 //
  15 //  You should have received a copy of the GNU General Public License
  16 //  along with this program; if not, write to the Free Software
  17 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18 //  02111-1307, USA.
  19 #include <config.h>
  20
  21 #include <math.h>
  22
  23 #include "ambient_sound.h"
  24 #include "object_factory.h"
  25 #include "lisp/lisp.h"
  26 #include "sector.h"
  27
  28 AmbientSound::AmbientSound(const lisp::Lisp& lisp)
  29 {
  30
  31   position.x=0;
  32   position.y=0;
  33
  34   dimension.x=0;
  35   dimension.y=0;
  36
  37   distance_factor=0;
  38   distance_bias=0;
  39   maximumvolume=1;
  40   sample="";
  41
  42   if (!(lisp.get("x", position.x)&&lisp.get("y", position.y))) {
  43     std::cerr << "No Position in ambient_sound"  << std::endl;
  44   }
  45
  46   lisp.get("width" , dimension.x);
  47   lisp.get("height", dimension.y);
  48
  49   lisp.get("distance_factor",distance_factor);
  50   lisp.get("distance_bias"  ,distance_bias  );
  51   lisp.get("sample"         ,sample         );
  52   lisp.get("volume"         ,maximumvolume  );
  53
  54   // set dimension to zero if smaller than 64, which is default size in flexlay
  55
  56   if ((dimension.x <= 64) || (dimension.y <= 64)) {
  57     dimension.x = 0;
  58     dimension.y = 0;
  59   }
  60
  61   // square all distances (saves us a sqrt later)
  62
  63   distance_bias*=distance_bias;
  64   distance_factor*=distance_factor;
  65
  66   // set default silence_distance
  67
  68   if (distance_factor == 0)
  69     silence_distance = 10e99;
  70   else
  71     silence_distance = 1/distance_factor;
  72
  73   lisp.get("silence_distance",silence_distance);
  74
  75   playing=-1; // not playing at the beginning
  76   latency=0;
  77 }
  78
  79 AmbientSound::~AmbientSound() {
  80   stop_playing();
  81 }
  82
  83 void
  84 AmbientSound::hit(Player& )
  85 {
  86 }
  87
  88 void
  89 AmbientSound::stop_playing() {
  90   if (playing>=0) {
  91     Mix_HaltChannel(playing);
  92     playing=-1;
  93   }
  94 }
  95
  96 void
  97 AmbientSound::start_playing()
  98 {
  99   playing=sound_manager->play_sound(sample,-1);
 100   Mix_Volume(playing,0);
 101   currentvolume=targetvolume=1e-20;
 102 }
 103
 104 void
 105 AmbientSound::update(float deltat)
 106 {
 107   if (latency--<=0) {
 108
 109     float px,py;
 110     float rx,ry;
 111
 112     // Player position
 113
 114     px=Sector::current()->player->get_pos().x;
 115     py=Sector::current()->player->get_pos().y;
 116
 117     // Relate to which point in the area
 118
 119     rx=px<position.x?position.x:
 120       (px<position.x+dimension.x?px:position.x+dimension.x);
 121     ry=py<position.y?position.y:
 122       (py<position.y+dimension.y?py:position.y+dimension.y);
 123
 124     // calculate square of distance
 125
 126     float sqrdistance=(px-rx)*(px-rx)+(py-ry)*(py-ry);
 127
 128     sqrdistance-=distance_bias;
 129
 130     // inside the bias: full volume (distance 0)
 131
 132     if (sqrdistance<0)
 133       sqrdistance=0;
 134
 135     // calculate target volume - will never become 0
 136
 137     targetvolume=1/(1+sqrdistance*distance_factor);
 138
 139     float rise=targetvolume/currentvolume;
 140
 141     // rise/fall half life?
 142
 143     currentvolume*=pow(rise,deltat*10);
 144     currentvolume += 1e-6; // volume is at least 1e-6 (0 would never rise)
 145
 146     if (playing>=0) {
 147
 148       // set the volume
 149       Mix_Volume(playing,(int)(currentvolume*maximumvolume*MIX_MAX_VOLUME));
 150
 151       if (sqrdistance>=silence_distance && currentvolume<1e-3)
 152         stop_playing();
 153       latency=0;
 154     } else {
 155       if (sqrdistance<silence_distance) {
 156         start_playing();
 157         latency=0;
 158       }
 159       else // set a reasonable latency
 160         latency=(int)(0.001/distance_factor);
 161       //(int)(10*((sqrdistance-silence_distance)/silence_distance));
 162     }
 163   }
 164
 165   // heuristically measured "good" latency maximum
 166
 167   //  if (latency>0.001/distance_factor)
 168   // latency=
 169 }
 170
 171 void
 172 AmbientSound::draw(DrawingContext &)
 173 {
 174 }
 175
 176 IMPLEMENT_FACTORY(AmbientSound, "ambient_sound");