1 // ambient_sound.cpp basti_
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.
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.
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16 // along with this program; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
23 #include "ambient_sound.h"
24 #include "object_factory.h"
25 #include "lisp/lisp.h"
28 AmbientSound::AmbientSound(const lisp::Lisp& lisp)
42 if (!(lisp.get("x", position.x)&&lisp.get("y", position.y))) {
43 std::cerr << "No Position in ambient_sound" << std::endl;
46 lisp.get("width" , dimension.x);
47 lisp.get("height", dimension.y);
49 lisp.get("distance_factor",distance_factor);
50 lisp.get("distance_bias" ,distance_bias );
51 lisp.get("sample" ,sample );
52 lisp.get("volume" ,maximumvolume );
54 // square all distances (saves us a sqrt later)
56 distance_bias*=distance_bias;
57 distance_factor*=distance_factor;
59 // set default silence_distance
61 if (distance_factor == 0)
62 silence_distance = 10e99;
64 silence_distance = 1/distance_factor;
66 lisp.get("silence_distance",silence_distance);
68 playing=-1; // not playing at the beginning
72 AmbientSound::~AmbientSound() {
77 AmbientSound::hit(Player& )
82 AmbientSound::stop_playing() {
84 Mix_HaltChannel(playing);
90 AmbientSound::start_playing()
92 playing=sound_manager->play_sound(sample,-1);
93 Mix_Volume(playing,0);
94 currentvolume=targetvolume=1e-20;
98 AmbientSound::update(float deltat)
107 px=Sector::current()->player->get_pos().x;
108 py=Sector::current()->player->get_pos().y;
110 // Relate to which point in the area
112 rx=px<position.x?position.x:
113 (px<position.x+dimension.x?px:position.x+dimension.x);
114 ry=py<position.y?position.y:
115 (py<position.y+dimension.y?py:position.y+dimension.y);
117 // calculate square of distance
119 float sqrdistance=(px-rx)*(px-rx)+(py-ry)*(py-ry);
121 sqrdistance-=distance_bias;
123 // inside the bias: full volume (distance 0)
128 // calculate target volume - will never become 0
130 targetvolume=1/(1+sqrdistance*distance_factor);
132 float rise=targetvolume/currentvolume;
134 // rise/fall half life?
136 currentvolume*=pow(rise,deltat*10);
137 currentvolume += 1e-6; // volume is at least 1e-6 (0 would never rise)
142 Mix_Volume(playing,(int)(currentvolume*maximumvolume*MIX_MAX_VOLUME));
144 if (sqrdistance>=silence_distance && currentvolume<1e-3)
148 if (sqrdistance<silence_distance) {
152 else // set a reasonable latency
153 latency=(int)(0.001/distance_factor);
154 //(int)(10*((sqrdistance-silence_distance)/silence_distance));
158 // heuristically measured "good" latency maximum
160 // if (latency>0.001/distance_factor)
165 AmbientSound::draw(DrawingContext &)
169 IMPLEMENT_FACTORY(AmbientSound, "ambient_sound");