GLTexImage.h

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//  File:       GLTexImage.h
//  Author:     Changchang Wu
//  Description : interface for the GLTexImage class.
//      GLTexImage:     naive texture class. 
//                      sevral different quad drawing functions are provied
//      GLTexPacked:    packed version (four value packed as four channels of a pixel)
//      GLTexInput:     GLTexImage + some input information
//
//  Copyright (c) 2007 University of North Carolina at Chapel Hill
//  All Rights Reserved
//
//  Permission to use, copy, modify and distribute this software and its
//  documentation for educational, research and non-profit purposes, without
//  fee, and without a written agreement is hereby granted, provided that the
//  above copyright notice and the following paragraph appear in all copies.
//  
//  The University of North Carolina at Chapel Hill make no representations
//  about the suitability of this software for any purpose. It is provided
//  'as is' without express or implied warranty. 
//
//  Please send BUG REPORTS to ccwu@cs.unc.edu
//
 
 
#ifndef GL_TEX_IMAGE_H
#define GL_TEX_IMAGE_H
 
class GlobalUtil;
class GLTexImage :public GlobalUtil 
{   
protected:
    GLuint  _texID;
    int     _imgWidth;
    int     _imgHeight;
    int     _texWidth;
    int     _texHeight;
    int     _drawWidth;
    int     _drawHeight;
public:
    static void DetachFBO(int i);
    static void UnbindTex();
    static void UnbindMultiTex(int n);
    static void DrawQuad(float x1, float x2, float y1, float y2);
 
public:
    virtual void DrawQuadUS(int scale);
    virtual void DrawQuadDS(int scale);
    virtual void DrawImage();
    virtual void TexConvertRGB();
    virtual void ZeroHistoMargin();
    virtual void SetImageSize(int width, int height);
    virtual void InitTexture(int width, int height, int clamp_to_edge =1 );
    void InitTexture(int width, int height, int clamp_to_edge, GLuint format);
    virtual void FillMargin(int marginx, int marginy);
public:
    void DrawScaledQuad(float scale);
    int  CopyToPBO(GLuint pbo, int width, int height, GLenum format = GL_RGBA);
    void CopyFromPBO(GLuint pbo, int width, int height, GLenum format = GL_RGBA);
    void FitRealTexViewPort();
    void DrawQuadMT8();
    void DrawQuadMT4();
    void DrawQuadReduction();
    void DrawQuadReduction(int w, int h);
    void DrawMargin(int right, int bottom);
    void DrawQuad();
    void FitTexViewPort();
    void ZeroHistoMargin(int hw, int hh);
    int  CheckTexture();
    void SaveToASCII(const char* path);
public:
    void AttachToFBO(int i );
    void BindTex();
    operator GLuint (){return _texID;}  
    GLuint GetTexID(){return _texID;}
    int GetImgPixelCount(){return _imgWidth*_imgHeight;}
    int GetTexPixelCount(){return _texWidth*_texHeight;}
    int GetImgWidth(){return _imgWidth;}
    int GetImgHeight(){return _imgHeight;}
    int GetTexWidth(){return _texWidth;}
    int GetTexHeight(){return _texHeight;}
    int GetDrawWidth(){return _drawWidth;}
    int GetDrawHeight(){return _drawHeight;}
    //int   IsTexTight(){return _texWidth == _drawWidth && _texHeight == _drawHeight;}
    int IsTexPacked(){return _drawWidth != _imgWidth;}
    GLTexImage();
    virtual ~GLTexImage();
    friend class SiftGPU;
};
 
//class for handle data input, to support all openGL-supported data format, 
//data are first uploaded to an openGL texture then converted, and optionally
//when the datatype is simple, we downsample/convert on cpu
class GLTexInput:public GLTexImage
{
public:
    int      _down_sampled;
    int      _rgb_converted;
    int      _data_modified;
 
    float *        _converted_data;
    const void*    _pixel_data;
public:
    static int  IsSimpleGlFormat(unsigned int gl_format, unsigned int gl_type)
    {
        //the formats there is a cpu code to conver rgb and downsample
         return (gl_format ==GL_LUMINANCE ||gl_format == GL_LUMINANCE_ALPHA||
                gl_format == GL_RGB||   gl_format == GL_RGBA||
                gl_format == GL_BGR || gl_format == GL_BGRA) && 
                (gl_type == GL_UNSIGNED_BYTE || gl_type == GL_FLOAT || gl_type == GL_UNSIGNED_SHORT); 
    }
//in vc6, template member function doesn't work
#if !defined(_MSC_VER) || _MSC_VER > 1200
    template <class Uint> 
    static int DownSamplePixelDataI(unsigned int gl_format, int width, int height, 
        int ds, const Uint * pin, Uint * pout);
    template <class Uint> 
    static int DownSamplePixelDataI2F(unsigned int gl_format, int width, int height, 
        int ds, const Uint * pin, float * pout, int skip  = 0);
#endif
    static int DownSamplePixelDataF(unsigned int gl_format, int width, int height, 
        int ds, const float * pin, float * pout, int skip = 0);
    static int TruncateWidthCU(int w) {return  w & 0xfffffffc; }
public:
    GLTexInput() : _down_sampled(0), _rgb_converted(0), _data_modified(0), 
                    _converted_data(0), _pixel_data(0){}
    int SetImageData(int width, int height, const void * data, 
                    unsigned int gl_format, unsigned int gl_type);
    int LoadImageFile(char * imagepath, int & w, int &h);
    void VerifyTexture();
    virtual ~GLTexInput();
};
 
//GLTexPacked doesn't have any data
//so that we can use the GLTexImage* pointer to index a GLTexPacked Vector
 
class GLTexPacked:public GLTexImage
{
public:
    virtual void    DrawImage();
    virtual void    DrawQuadUS(int scale);
    virtual void    DrawQuadDS(int scale);
    virtual void    FillMargin(int marginx, int marginy);
    virtual void    InitTexture(int width, int height, int clamp_to_edge =1);
    virtual void    TexConvertRGB();
    virtual void    SetImageSize(int width, int height);
    virtual void    ZeroHistoMargin();
    //virtual void  GetHistWH(int& w, int& h){return w = (3 + sz)>>1;}
public:
    void    DrawMargin(int right, int bottom, int mx, int my);
    GLTexPacked():GLTexImage(){}
};
 
 
#endif // !defined(GL_TEX_IMAGE_H)