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