# Visualization Library

A lightweight C++ OpenGL middleware for 2D/3D graphics

[Home] [Tutorials] [All Classes] [Grouped Classes]

- Main Page
- Namespaces
- Classes
- Files

- File List
- File Members

# D:/VL/BuildSystem/VL_DISTRO/Visualization_Library_SDK/src/vlCore/BufferedStream.hpp

Go to the documentation of this file.

    00001 /**************************************************************************************/
    00002 /*                                                                                    */
    00003 /*  Visualization Library                                                             */
    00004 /*  http://www.visualizationlibrary.com                                               */
    00005 /*                                                                                    */
    00006 /*  Copyright (c) 2005-2010, Michele Bosi                                             */
    00007 /*  All rights reserved.                                                              */
    00008 /*                                                                                    */
    00009 /*  Redistribution and use in source and binary forms, with or without modification,  */
    00010 /*  are permitted provided that the following conditions are met:                     */
    00011 /*                                                                                    */
    00012 /*  - Redistributions of source code must retain the above copyright notice, this     */
    00013 /*  list of conditions and the following disclaimer.                                  */
    00014 /*                                                                                    */
    00015 /*  - Redistributions in binary form must reproduce the above copyright notice, this  */
    00016 /*  list of conditions and the following disclaimer in the documentation and/or       */
    00017 /*  other materials provided with the distribution.                                   */
    00018 /*                                                                                    */
    00019 /*  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND   */
    00020 /*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED     */
    00021 /*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE            */
    00022 /*  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR  */
    00023 /*  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    */
    00024 /*  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;      */
    00025 /*  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON    */
    00026 /*  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT           */
    00027 /*  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS     */
    00028 /*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.                      */
    00029 /*                                                                                    */
    00030 /**************************************************************************************/
    00031
    00032 #ifndef BufferedStream_INCLUDE_ONCE
    00033 #define BufferedStream_INCLUDE_ONCE
    00034
    00035 #include <vlCore/String.hpp>
    00036 #include <vlCore/VirtualFile.hpp>
    00037 #include <string>
    00038 #include <vector>
    00039
    00040 namespace vl
    00041 {
    00042 //-----------------------------------------------------------------------------
    00043 // BufferedStream
    00044 //-----------------------------------------------------------------------------
    00048   template<class Element_Type, int Chunk_Size>
    00049   class BufferedStream: public Object
    00050   {
    00051   public:
    00052     virtual const char* className() { return "vl::BufferedStream"; }
    00053
    00054     BufferedStream()
    00055     {
    00056       mSize = 0;
    00057       mPtr  = 0;
    00058       mBuffer.resize(Chunk_Size);
    00059     }
    00060
    00061     void seek(long long pos)
    00062     {
    00063       mSize = 0;
    00064       mPtr  = 0;
    00065       if ( inputFile() )
    00066         inputFile()->seekSet(pos);
    00067     }
    00068
    00069     bool readToken(Element_Type* token)
    00070     {
    00071       if ( mUngetBuffer.size() )
    00072       {
    00073         *token = mUngetBuffer.back();
    00074         mUngetBuffer.pop_back();
    00075         return true;
    00076       }
    00077
    00078       if (bufferEmpty())
    00079         fillBuffer();
    00080       if (bufferEmpty())
    00081         return false;
    00082       else
    00083       {
    00084         *token = mBuffer[mPtr];
    00085         mPtr++;
    00086         return true;
    00087       }
    00088     }
    00089
    00090     bool bufferEmpty()
    00091     {
    00092       return mPtr == mSize;
    00093     }
    00094
    00095     int fillBuffer()
    00096     {
    00097       if ( inputFile() )
    00098       {
    00099         if ( !inputFile()->isOpen() )
    00100           if(!inputFile()->open(OM_ReadOnly))
    00101             return 0;
    00102
    00103         mPtr = 0;
    00104         mSize = (int)inputFile()->read(&mBuffer[0], Chunk_Size);
    00105         return mSize;
    00106       }
    00107       else
    00108       {
    00109         return 0;
    00110       }
    00111     }
    00112
    00113     void setInputFile(VirtualFile* file)
    00114     {
    00115       mInputFile = file;
    00116     }
    00117
    00118     VirtualFile* inputFile() const
    00119     {
    00120       return mInputFile.get();
    00121     }
    00122
    00123     void ungetToken(const Element_Type& token)
    00124     {
    00125       mUngetBuffer.push_back(token);
    00126     }
    00127
    00128   protected:
    00129     ref<VirtualFile> mInputFile;
    00130     std::vector<Element_Type> mUngetBuffer;
    00131     std::vector<Element_Type> mBuffer;
    00132     int mPtr;
    00133     int mSize;
    00134   };
    00135 }
    00136
    00137 #endif

Visualization Library v2011.05.1142 Reference Documentation
Copyright 2005-2011 Michele Bosi. All rights reserved.
Updated on Thu May 26 2011 22:51:20.
Permission is granted to use this page to write and publish articles regarding Visualization Library.