funcs_sound.cpp

   1 /*
   2 Copyright (c)2006-2008 - Brett Lajzer
   3
   4 See LICENSE for license information.
   5 */
   6
   7 #include <lua.hpp>
   8 #include "globals.h"
   9 #include "funcs_sound.h"
  10 #include <iostream>
  11
  12 static const int mix_channels = 16; //the number of mixing channels
  13 static const int mix_rate = 44100; //the mix rate in Hz
  14 static const int mix_format = MIX_DEFAULT_FORMAT; //the output format
  15 static const int mix_op_channels = 2; //output channels, 2 == stereo
  16 static const int mix_chunksize = 256; //output chunk size
  17
  18
  19 // open sound device
  20 void sound_open(){
  21   //Attempt to open the audio device in this format
  22   if(Mix_OpenAudio(mix_rate, mix_format, mix_op_channels, mix_chunksize)==-1){
  23     std::cerr << "ERROR: Couldn't Initialize SoundEngine: " << Mix_GetError() << "\n";
  24     return;
  25   }
  26
  27   //Allocate channels
  28   Mix_AllocateChannels(mix_channels);
  29
  30   //init music to null
  31   _music = 0;
  32 }
  33
  34 // close sound device
  35 void sound_close(){
  36   //free music if loaded
  37   if(_music != 0)
  38     Mix_FreeMusic(_music);
  39
  40   //free up the samples in the sample cache
  41   for(std::map<std::string, Mix_Chunk*>::iterator it = sample_cache.begin(); it != sample_cache.end(); it++)
  42     Mix_FreeChunk(it->second);
  43   sample_cache.clear();
  44
  45   Mix_CloseAudio();
  46 }
  47
  48
  49 //play a sample
  50 int l_playsample(lua_State *L){
  51   Mix_Chunk *s = (Mix_Chunk *)lua_touserdata(L,1);
  52
  53   if(s == NULL){
  54     return luaL_error(L, "ERROR: Can't play sample, is NULL.");
  55   }
  56
  57   if(Mix_PlayChannel(-1, s, 0)==-1){
  58     Mix_AllocateChannels(Mix_AllocateChannels(-1)+1);
  59     Mix_PlayChannel(-1, s, 0);
  60   }
  61   return 0;
  62 }
  63
  64 //stop all samples
  65 int l_stopsamples(lua_State *L){
  66   Mix_HaltChannel(-1);
  67   return 0;
  68 }
  69
  70 //load a sample
  71 int l_loadsample(lua_State *L){
  72   Mix_Chunk *temp = 0;
  73   std::map<std::string, Mix_Chunk *>::iterator s = sample_cache.find(std::string(luaL_checkstring(L,1)));
  74
  75   if( s == sample_cache.end()){
  76     temp = Mix_LoadWAV(luaL_checkstring(L,1));
  77
  78     if(temp == NULL){
  79       return luaL_error(L, "ERROR: Can't find sound file: \"%s\".", luaL_checkstring(L,1));
  80     }
  81
  82     sample_cache[std::string(luaL_checkstring(L,1))] = temp;
  83   }
  84
  85   lua_pushlightuserdata(L,temp);
  86   return 1;
  87 }
  88
  89 //unload a sample
  90 int l_unloadsample(lua_State *L){
  91   std::map<std::string, Mix_Chunk *>::iterator s = sample_cache.find(std::string(luaL_checkstring(L,1)));
  92   if(s != sample_cache.end()){
  93     Mix_FreeChunk(s->second);
  94     sample_cache.erase(s);
  95   }
  96   return 0;
  97 }
  98
  99 //clear the sample cache
 100 int l_clearsamples(lua_State *L){
 101   std::map<std::string, Mix_Chunk *>::iterator s = sample_cache.begin();
 102   for( ; s != sample_cache.end(); s++){
 103     Mix_FreeChunk(s->second);
 104   }
 105   sample_cache.clear();
 106   return 0;
 107 }
 108
 109
 110 //play music
 111 int l_playmusic(lua_State *L){
 112   std::string temp = std::string(luaL_checkstring(L,1));
 113   //free up music if not free
 114   if(_music != 0){
 115     if(Mix_PlayingMusic())
 116       Mix_HaltMusic();
 117     if(temp != _music_filename){ //only free if not loaded
 118       Mix_FreeMusic(_music);
 119      }
 120   }
 121   if(temp != _music_filename){ //only load if not loaded
 122     _music = Mix_LoadMUS(temp.c_str());
 123     _music_filename = temp;
 124   }
 125
 126   //don't halt on error, just output it
 127   if(!_music)
 128     return luaL_error(L, "ERROR: Can't load music file \"%s\" : %s.",luaL_checkstring(L,1), Mix_GetError());
 129
 130   //play the music
 131   Mix_PlayMusic(_music, lua_tointeger(L,2));
 132
 133   return 0;
 134 }
 135
 136 //stop music
 137 int l_stopmusic(lua_State *L){
 138   if(_music != 0){
 139     Mix_HaltMusic();
 140     Mix_FreeMusic(_music);
 141     _music_filename = "";
 142   }
 143   return 0;
 144 }