Texture.h

//********************************************
// Texture.h
//********************************************
// class CTexture
//********************************************
// This object stores a bitmap image used as
// an OpenGL texture.
// Files are stored as .bmp format. 
// Depth are currently 24 or 32 bits,
// Modes are : RGB, RGBA (alpha layer).
//********************************************
// pierre.alliez@cnet.francetelecom.fr
// Created : 17/12/97
// Modified : 18/02/98
//********************************************

#ifndef _TEXTURE_
#define _TEXTURE_

class CTexture : public CObject
{

// Members datas
private :

    unsigned char *m_pData;    // datas
    unsigned int   m_Width;    // width (pixels)
    unsigned int   m_Height;   // height (pixels)
    unsigned int   m_Depth;    // bits per pixel 
    CString        m_FileName; // texture image file name

    BITMAPINFOHEADER m_Header;      // image header (display on device context)
    unsigned int     m_WidthByte32; // width (in bytes, and 32 bits aligned)

public :

    // Construction / destruction
    CTexture();
    virtual ~CTexture();

    // File reading
    int ReadFile(const char *filename,unsigned int width=-1,unsigned int height=-1,unsigned int depth=-1);
    int ReadFileBMP(const char *filename);
    int ReadFileRAW(const char *filename,unsigned int width,unsigned int height,unsigned int depth);
    
    // File saving
    int SaveFile(char *filename);
    int SaveFileBMP(char *filename);
    int SaveFileRAW(char *filename);
    
    // Datas (explicit inline functions)
    unsigned char *GetData(void) { return m_pData; }
    unsigned int GetWidth(void)  { return m_Width; }
    unsigned int GetHeight(void) { return m_Height;}
    unsigned int GetDepth(void)  { return m_Depth; }
    CString GetFileName(void)    { return m_FileName; }

    // Misc
    int IsValid();
    int SameSize(CTexture *pTexture);
    int BGRtoRGB(void);
    int HigherPowerOfTwo(int value);
    int LowerPowerOfTwo(int value);

    // Updating
    void UpdateWidthByte32();
    void UpdateHeader();
    unsigned int WidthByte32(unsigned int width,unsigned int depth);

    // Alpha
    int HasAlpha() { return (m_Depth == 32); }
    int AddAlphaLayer(unsigned char alpha);
    int SetAlphaLayer(unsigned char alpha);
    int PutAlpha(CTexture *pTexture);   // Put an alpha layer from grey scale

    // DuplicateMirror
    int DuplicateMirror(int left=0,int top=0,int right=-1,int bottom=-1);
    int DuplicateRepeatWidth(int left=0,int top=0,int right=-1,int bottom=-1);
    int Extract(int left=0,int top=0,int right=-1,int bottom=-1);

    // Display
    int Draw(CDC *pDC,int xOffset=0,int yOffset=0, int width=-1, int height=-1);

    // Buffer
    int ReadBuffer(unsigned char *buffer, int width, int height, int depth);
    int Grey(unsigned int x,unsigned int y);

    // Memory
    void Free(void);

private :

    // Memory
    int Alloc(unsigned int width,unsigned int height,unsigned int depth);

};

#endif // _TEXTURE_