CentrED

(*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License, Version 1.0 only

 * (the "License").  You may not use this file except in compliance

 * with the License.

 *

 * You can obtain a copy of the license at

 * http://www.opensource.org/licenses/cddl1.php.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at

 * http://www.opensource.org/licenses/cddl1.php.  If applicable,

 * add the following below this CDDL HEADER, with the fields enclosed

 * by brackets "[]" replaced with your own identifying * information:

 *      Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 *

 *

 *      Portions Copyright 2009 Andreas Schneider

 *)

unit URadarProvider;

{$mode objfpc}{$H+}

interface

uses

  SysUtils, Classes, UBufferedStreams;

type

  { TRadarProvider }

  TRadarProvider = class

    constructor Create; overload; virtual;

    constructor Create(AData: TStream; AReadOnly: Boolean = False); overload; virtual;

    constructor Create(AData: string; AReadOnly: Boolean = False); overload; virtual;

    destructor Destroy; override;    

  protected

    FData: TBufferedReader;

    FReadOnly: Boolean;

  public

    function GetColor(AID: Integer): Word;

    procedure SetColor(AID: Integer; AColor: Word);

  end;

implementation

{ TRaderProvider }

constructor TRadarProvider.Create;

begin

  inherited Create;

end;

constructor TRadarProvider.Create(AData: TStream; AReadOnly: Boolean);

begin

  Create;

  FData := TBufferedReader.Create(AData, False);

  FReadOnly := AReadOnly;

end;

constructor TRadarProvider.Create(AData: string; AReadOnly: Boolean);

var

  mode: Word;

begin

  Create;

  if AReadOnly then

    mode := fmOpenRead or fmShareDenyWrite

  else

    mode := fmOpenReadWrite or fmShareDenyWrite;

  FData := TBufferedReader.Create(TFileStream.Create(AData, mode), True);

  FReadOnly := AReadOnly;

end;

destructor TRadarProvider.Destroy;

begin

  FreeAndNil(FData);

  inherited Destroy;

end;

function TRadarProvider.GetColor(AID: Integer): Word;

begin

  Result := 0;

  if (AID >= 0) and (AID < $10000) then

  begin

    FData.Position := SizeOf(Word) * AID;

    FData.Read(Result, SizeOf(Word));

  end;

end;

procedure TRadarProvider.SetColor(AID: Integer; AColor: Word);

begin

  if (not FReadOnly) and (AID >= 0) and (AID < $10000) then

  begin

    FData.Position := SizeOf(Word) * AID;

    FData.Write(AColor, SizeOf(Word));

  end;

end;

end.