src/engine/e_soundfile.pas

   1 (* Copyright (C)  Doom 2D: Forever Developers
   2  *
   3  * This program is free software: you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation, version 3 of the License ONLY.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  14  *)
  15 {$INCLUDE ../shared/a_modes.inc}
  16 unit e_soundfile;
  17
  18 interface
  19
  20 type
  21   TSoundLoader = class;
  22
  23   TSoundFormat = record
  24     SampleBits: Integer;
  25     SampleRate: Integer;
  26     Channels: Integer;
  27   end;
  28
  29   // each sound file format has its own loader factory and loader class,
  30   // each sound has its own loader instance for streaming purposes
  31
  32   TSoundLoader = class
  33   protected
  34     FFormat: TSoundFormat;
  35     FStreaming: Boolean;
  36
  37   public
  38     function Load(Data: Pointer; Len: LongWord; Loop: Boolean): Boolean; virtual; abstract; overload;
  39     function Load(FName: string; Loop: Boolean): Boolean; virtual; abstract; overload;
  40
  41     function Finished(): Boolean; virtual; abstract;
  42     function Restart(): Boolean; virtual; abstract;
  43     function FillBuffer(Buf: Pointer; Len: LongWord): LongWord; virtual; abstract;
  44
  45     procedure Free(); virtual; abstract;
  46
  47     property Format: TSoundFormat read FFormat;
  48     property Streaming: Boolean read FStreaming;
  49   end;
  50
  51   TSoundLoaderFactory = class
  52   public
  53     function MatchHeader(Data: Pointer; Len: LongWord): Boolean; virtual; abstract;
  54     function MatchExtension(FName: string): Boolean; virtual; abstract;
  55     function GetLoader(): TSoundLoader; virtual; abstract;
  56   end;
  57
  58 function e_GetSoundLoader(Data: Pointer; Len: LongWord): TSoundLoader; overload;
  59 function e_GetSoundLoader(FName: string): TSoundLoader; overload;
  60
  61 procedure e_AddSoundLoader(Loader: TSoundLoaderFactory);
  62
  63 implementation
  64
  65 var
  66   e_SoundLoaders: array of TSoundLoaderFactory;
  67
  68 function e_GetSoundLoader(FName: string): TSoundLoader; overload;
  69 var
  70   I: Integer;
  71 begin
  72   Result := nil;
  73   for I := Low(e_SoundLoaders) to High(e_SoundLoaders) do
  74     if e_SoundLoaders[I].MatchExtension(FName) then
  75     begin
  76       Result := e_SoundLoaders[I].GetLoader();
  77       break;
  78     end;
  79 end;
  80
  81 function e_GetSoundLoader(Data: Pointer; Len: LongWord): TSoundLoader; overload;
  82 var
  83   I: Integer;
  84 begin
  85   Result := nil;
  86   for I := Low(e_SoundLoaders) to High(e_SoundLoaders) do
  87     if e_SoundLoaders[I].MatchHeader(Data, Len) then
  88     begin
  89       Result := e_SoundLoaders[I].GetLoader();
  90       break;
  91     end;
  92 end;
  93
  94 procedure e_AddSoundLoader(Loader: TSoundLoaderFactory);
  95 begin
  96   SetLength(e_SoundLoaders, Length(e_SoundLoaders) + 1);
  97   e_SoundLoaders[High(e_SoundLoaders)] := Loader;
  98 end;
  99
 100 end.