source: liacs/MIR2010/Sample/cximage/ximapal.cpp@ 93

// xImaPal.cpp : Palette and Pixel functions
/* 07/08/2001 v1.00 - Davide Pizzolato - www.xdp.it
 * CxImage version 6.0.0 02/Feb/2008
 */

#include "ximage.h"

////////////////////////////////////////////////////////////////////////////////
/**
 * returns the palette dimension in byte
 */
DWORD CxImage::GetPaletteSize()
{
        return (head.biClrUsed * sizeof(RGBQUAD));
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPaletteColor(BYTE idx, BYTE r, BYTE g, BYTE b, BYTE alpha)
{
        if ((pDib)&&(head.biClrUsed)){
                BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
                if (idx<head.biClrUsed){
                        long ldx=idx*sizeof(RGBQUAD);
                        iDst[ldx++] = (BYTE) b;
                        iDst[ldx++] = (BYTE) g;
                        iDst[ldx++] = (BYTE) r;
                        iDst[ldx] = (BYTE) alpha;
                        info.last_c_isvalid = false;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPaletteColor(BYTE idx, RGBQUAD c)
{
        if ((pDib)&&(head.biClrUsed)){
                BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
                if (idx<head.biClrUsed){
                        long ldx=idx*sizeof(RGBQUAD);
                        iDst[ldx++] = (BYTE) c.rgbBlue;
                        iDst[ldx++] = (BYTE) c.rgbGreen;
                        iDst[ldx++] = (BYTE) c.rgbRed;
                        iDst[ldx] = (BYTE) c.rgbReserved;
                        info.last_c_isvalid = false;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPaletteColor(BYTE idx, COLORREF cr)
{
        if ((pDib)&&(head.biClrUsed)){
                BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
                if (idx<head.biClrUsed){
                        long ldx=idx*sizeof(RGBQUAD);
                        iDst[ldx++] = (BYTE) GetBValue(cr);
                        iDst[ldx++] = (BYTE) GetGValue(cr);
                        iDst[ldx++] = (BYTE) GetRValue(cr);
                        iDst[ldx] = (BYTE) 0;
                        info.last_c_isvalid = false;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
/**
 * returns the pointer to the first palette index
 */
RGBQUAD* CxImage::GetPalette() const
{
        if ((pDib)&&(head.biClrUsed))
                return (RGBQUAD*)((BYTE*)pDib + sizeof(BITMAPINFOHEADER));
        return NULL;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns the color of the specified index.
 */
RGBQUAD CxImage::GetPaletteColor(BYTE idx)
{
        RGBQUAD rgb = {0,0,0,0};
        if ((pDib)&&(head.biClrUsed)){
                BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
                if (idx<head.biClrUsed){
                        long ldx=idx*sizeof(RGBQUAD);
                        rgb.rgbBlue = iDst[ldx++];
                        rgb.rgbGreen=iDst[ldx++];
                        rgb.rgbRed =iDst[ldx++];
                        rgb.rgbReserved = iDst[ldx];
                }
        }
        return rgb;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns the palette index of the specified pixel.
 */
BYTE CxImage::GetPixelIndex(long x,long y)
{
        if ((pDib==NULL)||(head.biClrUsed==0)) return 0;

        if ((x<0)||(y<0)||(x>=head.biWidth)||(y>=head.biHeight)) {
                if (info.nBkgndIndex >= 0)      return (BYTE)info.nBkgndIndex;
                else return *info.pImage;
        }
        if (head.biBitCount==8){
                return info.pImage[y*info.dwEffWidth + x];
        } else {
                BYTE pos;
                BYTE iDst= info.pImage[y*info.dwEffWidth + (x*head.biBitCount >> 3)];
                if (head.biBitCount==4){
                        pos = (BYTE)(4*(1-x%2));
                        iDst &= (0x0F<<pos);
                        return (BYTE)(iDst >> pos);
                } else if (head.biBitCount==1){
                        pos = (BYTE)(7-x%8);
                        iDst &= (0x01<<pos);
                        return (BYTE)(iDst >> pos);
                }
        }
        return 0;
}
////////////////////////////////////////////////////////////////////////////////
BYTE CxImage::BlindGetPixelIndex(const long x,const long y)
{
#ifdef _DEBUG
        if ((pDib==NULL) || (head.biClrUsed==0) || !IsInside(x,y))
  #if CXIMAGE_SUPPORT_EXCEPTION_HANDLING
                throw 0;
  #else
                return 0;
  #endif
#endif

        if (head.biBitCount==8){
                return info.pImage[y*info.dwEffWidth + x];
        } else {
                BYTE pos;
                BYTE iDst= info.pImage[y*info.dwEffWidth + (x*head.biBitCount >> 3)];
                if (head.biBitCount==4){
                        pos = (BYTE)(4*(1-x%2));
                        iDst &= (0x0F<<pos);
                        return (BYTE)(iDst >> pos);
                } else if (head.biBitCount==1){
                        pos = (BYTE)(7-x%8);
                        iDst &= (0x01<<pos);
                        return (BYTE)(iDst >> pos);
                }
        }
        return 0;
}
////////////////////////////////////////////////////////////////////////////////
RGBQUAD CxImage::GetPixelColor(long x,long y, bool bGetAlpha)
{
//      RGBQUAD rgb={0,0,0,0};
        RGBQUAD rgb=info.nBkgndColor; //<mpwolski>
        if ((pDib==NULL)||(x<0)||(y<0)||
                (x>=head.biWidth)||(y>=head.biHeight)){
                if (info.nBkgndIndex >= 0){
                        if (head.biBitCount<24) return GetPaletteColor((BYTE)info.nBkgndIndex);
                        else return info.nBkgndColor;
                } else if (pDib) return GetPixelColor(0,0);
                return rgb;
        }

        if (head.biClrUsed){
                rgb = GetPaletteColor(BlindGetPixelIndex(x,y));
        } else {
                BYTE* iDst  = info.pImage + y*info.dwEffWidth + x*3;
                rgb.rgbBlue = *iDst++;
                rgb.rgbGreen= *iDst++;
                rgb.rgbRed  = *iDst;
        }
#if CXIMAGE_SUPPORT_ALPHA
        if (pAlpha && bGetAlpha) rgb.rgbReserved = BlindAlphaGet(x,y);
#else
        rgb.rgbReserved = 0;
#endif //CXIMAGE_SUPPORT_ALPHA
        return rgb;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * This is (a bit) faster version of GetPixelColor. 
 * It tests bounds only in debug mode (_DEBUG defined).
 * 
 * It is an error to request out-of-borders pixel with this method. 
 * In DEBUG mode an exception will be thrown, and data will be violated in non-DEBUG mode. 
 * \author ***bd*** 2.2004
 */
RGBQUAD CxImage::BlindGetPixelColor(const long x,const long y, bool bGetAlpha)
{
  RGBQUAD rgb;
#ifdef _DEBUG
        if ((pDib==NULL) || !IsInside(x,y))
  #if CXIMAGE_SUPPORT_EXCEPTION_HANDLING
                throw 0;
  #else
                {rgb.rgbReserved = 0; return rgb;}
  #endif
#endif

        if (head.biClrUsed){
                rgb = GetPaletteColor(BlindGetPixelIndex(x,y));
        } else {
                BYTE* iDst  = info.pImage + y*info.dwEffWidth + x*3;
                rgb.rgbBlue = *iDst++;
                rgb.rgbGreen= *iDst++;
                rgb.rgbRed  = *iDst;
                rgb.rgbReserved = 0; //needed for images without alpha layer
        }
#if CXIMAGE_SUPPORT_ALPHA
        if (pAlpha && bGetAlpha) rgb.rgbReserved = BlindAlphaGet(x,y);
#else
        rgb.rgbReserved = 0;
#endif //CXIMAGE_SUPPORT_ALPHA
        return rgb;
}
////////////////////////////////////////////////////////////////////////////////
BYTE CxImage::GetPixelGray(long x, long y)
{
        RGBQUAD color = GetPixelColor(x,y);
        return (BYTE)RGB2GRAY(color.rgbRed,color.rgbGreen,color.rgbBlue);
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::BlindSetPixelIndex(long x,long y,BYTE i)
{
#ifdef _DEBUG
        if ((pDib==NULL)||(head.biClrUsed==0)||
                (x<0)||(y<0)||(x>=head.biWidth)||(y>=head.biHeight))
  #if CXIMAGE_SUPPORT_EXCEPTION_HANDLING
                throw 0;
  #else
                return;
  #endif
#endif

        if (head.biBitCount==8){
                info.pImage[y*info.dwEffWidth + x]=i;
                return;
        } else {
                BYTE pos;
                BYTE* iDst= info.pImage + y*info.dwEffWidth + (x*head.biBitCount >> 3);
                if (head.biBitCount==4){
                        pos = (BYTE)(4*(1-x%2));
                        *iDst &= ~(0x0F<<pos);
                        *iDst |= ((i & 0x0F)<<pos);
                        return;
                } else if (head.biBitCount==1){
                        pos = (BYTE)(7-x%8);
                        *iDst &= ~(0x01<<pos);
                        *iDst |= ((i & 0x01)<<pos);
                        return;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPixelIndex(long x,long y,BYTE i)
{
        if ((pDib==NULL)||(head.biClrUsed==0)||
                (x<0)||(y<0)||(x>=head.biWidth)||(y>=head.biHeight)) return ;

        if (head.biBitCount==8){
                info.pImage[y*info.dwEffWidth + x]=i;
                return;
        } else {
                BYTE pos;
                BYTE* iDst= info.pImage + y*info.dwEffWidth + (x*head.biBitCount >> 3);
                if (head.biBitCount==4){
                        pos = (BYTE)(4*(1-x%2));
                        *iDst &= ~(0x0F<<pos);
                        *iDst |= ((i & 0x0F)<<pos);
                        return;
                } else if (head.biBitCount==1){
                        pos = (BYTE)(7-x%8);
                        *iDst &= ~(0x01<<pos);
                        *iDst |= ((i & 0x01)<<pos);
                        return;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPixelColor(long x,long y,COLORREF cr)
{
        SetPixelColor(x,y,RGBtoRGBQUAD(cr));
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::BlindSetPixelColor(long x,long y,RGBQUAD c, bool bSetAlpha)
{
#ifdef _DEBUG
        if ((pDib==NULL)||(x<0)||(y<0)||
                (x>=head.biWidth)||(y>=head.biHeight))
  #if CXIMAGE_SUPPORT_EXCEPTION_HANDLING
                throw 0;
  #else
                return;
  #endif
#endif
        if (head.biClrUsed)
                BlindSetPixelIndex(x,y,GetNearestIndex(c));
        else {
                BYTE* iDst = info.pImage + y*info.dwEffWidth + x*3;
                *iDst++ = c.rgbBlue;
                *iDst++ = c.rgbGreen;
                *iDst   = c.rgbRed;
        }
#if CXIMAGE_SUPPORT_ALPHA
        if (bSetAlpha) AlphaSet(x,y,c.rgbReserved);
#endif //CXIMAGE_SUPPORT_ALPHA
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPixelColor(long x,long y,RGBQUAD c, bool bSetAlpha)
{
        if ((pDib==NULL)||(x<0)||(y<0)||
                (x>=head.biWidth)||(y>=head.biHeight)) return;
        if (head.biClrUsed)
                BlindSetPixelIndex(x,y,GetNearestIndex(c));
        else {
                BYTE* iDst = info.pImage + y*info.dwEffWidth + x*3;
                *iDst++ = c.rgbBlue;
                *iDst++ = c.rgbGreen;
                *iDst   = c.rgbRed;
        }
#if CXIMAGE_SUPPORT_ALPHA
        if (bSetAlpha) AlphaSet(x,y,c.rgbReserved);
#endif //CXIMAGE_SUPPORT_ALPHA
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Blends the current pixel color with a new color.
 * \param x,y = pixel
 * \param c = new color
 * \param blend = can be from 0 (no effect) to 1 (full effect).
 * \param bSetAlpha = if true, blends also the alpha component stored in c.rgbReserved
 */
void CxImage::BlendPixelColor(long x,long y,RGBQUAD c, float blend, bool bSetAlpha)
{
        if ((pDib==NULL)||(x<0)||(y<0)||
                (x>=head.biWidth)||(y>=head.biHeight)) return;

        int a0 = (int)(256*blend);
        int a1 = 256 - a0;

        RGBQUAD c0 = BlindGetPixelColor(x,y);
        c.rgbRed  = (BYTE)((c.rgbRed * a0 + c0.rgbRed * a1)>>8);
        c.rgbBlue  = (BYTE)((c.rgbBlue * a0 + c0.rgbBlue * a1)>>8);
        c.rgbGreen  = (BYTE)((c.rgbGreen * a0 + c0.rgbGreen * a1)>>8);

        if (head.biClrUsed)
                BlindSetPixelIndex(x,y,GetNearestIndex(c));
        else {
                BYTE* iDst = info.pImage + y*info.dwEffWidth + x*3;
                *iDst++ = c.rgbBlue;
                *iDst++ = c.rgbGreen;
                *iDst   = c.rgbRed;
#if CXIMAGE_SUPPORT_ALPHA
                if (bSetAlpha) AlphaSet(x,y,c.rgbReserved);
#endif //CXIMAGE_SUPPORT_ALPHA
        }
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns the best palette index that matches a specified color.
 */
BYTE CxImage::GetNearestIndex(RGBQUAD c)
{
        if ((pDib==NULL)||(head.biClrUsed==0)) return 0;

        // <RJ> check matching with the previous result
        if (info.last_c_isvalid && (*(long*)&info.last_c == *(long*)&c)) return info.last_c_index;
        info.last_c = c;
        info.last_c_isvalid = true;

        BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
        long distance=200000;
        int i,j = 0;
        long k,l;
        int m = (int)(head.biClrImportant==0 ? head.biClrUsed : head.biClrImportant);
        for(i=0,l=0;i<m;i++,l+=sizeof(RGBQUAD)){
                k = (iDst[l]-c.rgbBlue)*(iDst[l]-c.rgbBlue)+
                        (iDst[l+1]-c.rgbGreen)*(iDst[l+1]-c.rgbGreen)+
                        (iDst[l+2]-c.rgbRed)*(iDst[l+2]-c.rgbRed);
//              k = abs(iDst[l]-c.rgbBlue)+abs(iDst[l+1]-c.rgbGreen)+abs(iDst[l+2]-c.rgbRed);
                if (k==0){
                        j=i;
                        break;
                }
                if (k<distance){
                        distance=k;
                        j=i;
                }
        }
        info.last_c_index = (BYTE)j;
        return (BYTE)j;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * swaps the blue and red components (for RGB images)
 * \param buffer : pointer to the pixels
 * \param length : number of bytes to swap. lenght may not exceed the scan line.
 */
void CxImage::RGBtoBGR(BYTE *buffer, int length)
{
        if (buffer && (head.biClrUsed==0)){
                BYTE temp;
                length = min(length,(int)info.dwEffWidth);
                length = min(length,(int)(3*head.biWidth));
                for (int i=0;i<length;i+=3){
                        temp = buffer[i]; buffer[i] = buffer[i+2]; buffer[i+2] = temp;
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
RGBQUAD CxImage::RGBtoRGBQUAD(COLORREF cr)
{
        RGBQUAD c;
        c.rgbRed = GetRValue(cr);       /* get R, G, and B out of DWORD */
        c.rgbGreen = GetGValue(cr);
        c.rgbBlue = GetBValue(cr);
        c.rgbReserved=0;
        return c;
}
////////////////////////////////////////////////////////////////////////////////
COLORREF CxImage::RGBQUADtoRGB (RGBQUAD c)
{
        return RGB(c.rgbRed,c.rgbGreen,c.rgbBlue);
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns the color of the specified index.
 * \param i = palette index
 * \param r, g, b = output color channels
 */
bool CxImage::GetPaletteColor(BYTE i, BYTE* r, BYTE* g, BYTE* b)
{
        RGBQUAD* ppal=GetPalette();
        if (ppal) {
                *r = ppal[i].rgbRed;
                *g = ppal[i].rgbGreen;
                *b = ppal[i].rgbBlue; 
                return true;
        }
        return false;
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPalette(DWORD n, BYTE *r, BYTE *g, BYTE *b)
{
        if ((!r)||(pDib==NULL)||(head.biClrUsed==0)) return;
        if (!g) g = r;
        if (!b) b = g;
        RGBQUAD* ppal=GetPalette();
        DWORD m=min(n,head.biClrUsed);
        for (DWORD i=0; i<m;i++){
                ppal[i].rgbRed=r[i];
                ppal[i].rgbGreen=g[i];
                ppal[i].rgbBlue=b[i];
        }
        info.last_c_isvalid = false;
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPalette(rgb_color *rgb,DWORD nColors)
{
        if ((!rgb)||(pDib==NULL)||(head.biClrUsed==0)) return;
        RGBQUAD* ppal=GetPalette();
        DWORD m=min(nColors,head.biClrUsed);
        for (DWORD i=0; i<m;i++){
                ppal[i].rgbRed=rgb[i].r;
                ppal[i].rgbGreen=rgb[i].g;
                ppal[i].rgbBlue=rgb[i].b;
        }
        info.last_c_isvalid = false;
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::SetPalette(RGBQUAD* pPal,DWORD nColors)
{
        if ((pPal==NULL)||(pDib==NULL)||(head.biClrUsed==0)) return;
        memcpy(GetPalette(),pPal,min(GetPaletteSize(),nColors*sizeof(RGBQUAD)));
        info.last_c_isvalid = false;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Sets (or replaces) the palette to gray scale palette.
 * The function doesn't change the pixels; for standard
 * gray scale conversion use GrayScale().
 */
void CxImage::SetGrayPalette()
{
        if ((pDib==NULL)||(head.biClrUsed==0)) return;
        RGBQUAD* pal=GetPalette();
        for (DWORD ni=0;ni<head.biClrUsed;ni++)
                pal[ni].rgbBlue=pal[ni].rgbGreen = pal[ni].rgbRed = (BYTE)(ni*(255/(head.biClrUsed-1)));
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Colorize the palette.
 * \sa Colorize
 */
void CxImage::BlendPalette(COLORREF cr,long perc)
{
        if ((pDib==NULL)||(head.biClrUsed==0)) return;
        BYTE* iDst = (BYTE*)(pDib) + sizeof(BITMAPINFOHEADER);
        DWORD i,r,g,b;
        RGBQUAD* pPal=(RGBQUAD*)iDst;
        r = GetRValue(cr);
        g = GetGValue(cr);
        b = GetBValue(cr);
        if (perc>100) perc=100;
        for(i=0;i<head.biClrUsed;i++){
                pPal[i].rgbBlue=(BYTE)((pPal[i].rgbBlue*(100-perc)+b*perc)/100);
                pPal[i].rgbGreen =(BYTE)((pPal[i].rgbGreen*(100-perc)+g*perc)/100);
                pPal[i].rgbRed =(BYTE)((pPal[i].rgbRed*(100-perc)+r*perc)/100);
        }
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns true if the image has 256 colors and a linear grey scale palette.
 */
bool CxImage::IsGrayScale()
{
        RGBQUAD* ppal=GetPalette();
        if(!(pDib && ppal && head.biClrUsed)) return false;
        for(DWORD i=0;i<head.biClrUsed;i++){
                if (ppal[i].rgbBlue!=i || ppal[i].rgbGreen!=i || ppal[i].rgbRed!=i) return false;
        }
        return true;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * swap two indexes in the image and their colors in the palette
 */
void CxImage::SwapIndex(BYTE idx1, BYTE idx2)
{
        RGBQUAD* ppal=GetPalette();
        if(!(pDib && ppal)) return;
        //swap the colors
        RGBQUAD tempRGB=GetPaletteColor(idx1);
        SetPaletteColor(idx1,GetPaletteColor(idx2));
        SetPaletteColor(idx2,tempRGB);
        //swap the pixels
        BYTE idx;
        for(long y=0; y < head.biHeight; y++){
                for(long x=0; x < head.biWidth; x++){
                        idx=BlindGetPixelIndex(x,y);
                        if (idx==idx1) BlindSetPixelIndex(x,y,idx2);
                        if (idx==idx2) BlindSetPixelIndex(x,y,idx1);
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
/**
 * swap Red and Blue colors
 */
void CxImage::SwapRGB2BGR()
{
        if (!pDib) return;

        if (head.biClrUsed){
                RGBQUAD* ppal=GetPalette();
                BYTE b;
                if(!ppal) return;
                for(WORD a=0;a<head.biClrUsed;a++){
                        b=ppal[a].rgbBlue; ppal[a].rgbBlue=ppal[a].rgbRed; ppal[a].rgbRed=b;
                }
        } else {
                for(long y=0;y<head.biHeight;y++){
                        RGBtoBGR(GetBits(y),3*head.biWidth);
                }
        }
}
////////////////////////////////////////////////////////////////////////////////
bool CxImage::IsTransparent(long x, long y)
{
        if (!pDib) return false;

        if (info.nBkgndIndex>=0){
                if (head.biClrUsed){
                        if (GetPixelIndex(x,y) == info.nBkgndIndex) return true;
                } else {
                        RGBQUAD ct = info.nBkgndColor;
                        RGBQUAD c = GetPixelColor(x,y,false);
                        if (*(long*)&c==*(long*)&ct) return true;
                }
        }

#if CXIMAGE_SUPPORT_ALPHA
        if (pAlpha) return AlphaGet(x,y)==0;
#endif

        return false;
}
////////////////////////////////////////////////////////////////////////////////
bool CxImage::GetTransparentMask(CxImage* iDst)
{
        if (!pDib) return false;

        CxImage tmp;
        tmp.Create(head.biWidth, head.biHeight, 1, GetType());
        tmp.SetStdPalette();
        tmp.Clear(0);

        for(long y=0; y<head.biHeight; y++){
                for(long x=0; x<head.biWidth; x++){
                        if (IsTransparent(x,y)){
                                tmp.BlindSetPixelIndex(x,y,1);
                        }
                }
        }

        if (iDst) iDst->Transfer(tmp);
        else Transfer(tmp);

        return true;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Checks if image has the same palette, if any.
 * \param img = image to compare.
 * \param bCheckAlpha = check also the rgbReserved field.
 */
bool CxImage::IsSamePalette(CxImage &img, bool bCheckAlpha)
{
        if (head.biClrUsed != img.head.biClrUsed)
                return false;
        if (head.biClrUsed == 0)
                return false;

        RGBQUAD c1,c2;
        for (DWORD n=0; n<head.biClrUsed; n++){
                c1 = GetPaletteColor((BYTE)n);
                c2 = img.GetPaletteColor((BYTE)n);
                if (c1.rgbRed != c2.rgbRed) return false;
                if (c1.rgbBlue != c2.rgbBlue) return false;
                if (c1.rgbGreen != c2.rgbGreen) return false;
                if (bCheckAlpha && (c1.rgbReserved != c2.rgbReserved)) return false;
        }
        return true;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * \sa SetClrImportant
 */
DWORD CxImage::GetClrImportant() const
{
        return head.biClrImportant;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * sets the maximum number of colors that some functions like
 * DecreaseBpp() or GetNearestIndex() will use on indexed images
 * \param ncolors should be less than 2^bpp,
 * or 0 if all the colors are important.
 */
void CxImage::SetClrImportant(DWORD ncolors)
{
        if (ncolors==0 || ncolors>256) {
                head.biClrImportant = 0;
                return;
        }

        switch(head.biBitCount){
        case 1:
                head.biClrImportant = min(ncolors,2);
                break;
        case 4:
                head.biClrImportant = min(ncolors,16);
                break;
        case 8:
                head.biClrImportant = ncolors;
                break;
        }
        return;
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Returns pointer to pixel. Currently implemented only for truecolor images.
 *  
 * \param  x,y - coordinates
 *
 * \return pointer to first byte of pixel data
 *
 * \author ***bd*** 2.2004
 */
void* CxImage::BlindGetPixelPointer(const long x, const long y)
{
#ifdef _DEBUG
        if ((pDib==NULL) || !IsInside(x,y))
  #if CXIMAGE_SUPPORT_EXCEPTION_HANDLING
                throw 0;
  #else
                return 0;
  #endif
#endif
  if (!IsIndexed())
    return info.pImage + y*info.dwEffWidth + x*3;
  else
    return 0;
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::DrawLine(int StartX, int EndX, int StartY, int EndY, COLORREF cr)
{
        DrawLine(StartX, EndX, StartY, EndY, RGBtoRGBQUAD(cr));
}
////////////////////////////////////////////////////////////////////////////////
void CxImage::DrawLine(int StartX, int EndX, int StartY, int EndY, RGBQUAD color, bool bSetAlpha)
{
        if (!pDib) return;
        //////////////////////////////////////////////////////
        // Draws a line using the Bresenham line algorithm
        // Thanks to Jordan DeLozier <JDL>
        //////////////////////////////////////////////////////
        int x1 = StartX;
        int y1 = StartY;
        int x = x1;                       // Start x off at the first pixel
        int y = y1;                       // Start y off at the first pixel
        int x2 = EndX;
        int y2 = EndY;

        int xinc1,xinc2,yinc1,yinc2;      // Increasing values
        int den, num, numadd,numpixels;   
        int deltax = abs(x2 - x1);        // The difference between the x's
        int deltay = abs(y2 - y1);        // The difference between the y's

        // Get Increasing Values
        if (x2 >= x1) {                // The x-values are increasing
                xinc1 = 1;
                xinc2 = 1;
        } else {                         // The x-values are decreasing
                xinc1 = -1;
                xinc2 = -1;
        }

        if (y2 >= y1) {                // The y-values are increasing
                yinc1 = 1;
                yinc2 = 1;
        } else {                         // The y-values are decreasing
                yinc1 = -1;
                yinc2 = -1;
        }

        // Actually draw the line
        if (deltax >= deltay)         // There is at least one x-value for every y-value
        {
                xinc1 = 0;                  // Don't change the x when numerator >= denominator
                yinc2 = 0;                  // Don't change the y for every iteration
                den = deltax;
                num = deltax / 2;
                numadd = deltay;
                numpixels = deltax;         // There are more x-values than y-values
        }
        else                          // There is at least one y-value for every x-value
        {
                xinc2 = 0;                  // Don't change the x for every iteration
                yinc1 = 0;                  // Don't change the y when numerator >= denominator
                den = deltay;
                num = deltay / 2;
                numadd = deltax;
                numpixels = deltay;         // There are more y-values than x-values
        }
        
        for (int curpixel = 0; curpixel <= numpixels; curpixel++)
        {
                // Draw the current pixel
                SetPixelColor(x,y,color,bSetAlpha);
                
                num += numadd;              // Increase the numerator by the top of the fraction
                if (num >= den)             // Check if numerator >= denominator
                {
                        num -= den;               // Calculate the new numerator value
                        x += xinc1;               // Change the x as appropriate
                        y += yinc1;               // Change the y as appropriate
                }
                x += xinc2;                 // Change the x as appropriate
                y += yinc2;                 // Change the y as appropriate
        }
}
////////////////////////////////////////////////////////////////////////////////
/**
 * Sets a palette with standard colors for 1, 4 and 8 bpp images.
 */
void CxImage::SetStdPalette()
{
        if (!pDib) return;
        switch (head.biBitCount){
        case 8:
                {
                        const BYTE pal256[1024] = {0,0,0,0,0,0,128,0,0,128,0,0,0,128,128,0,128,0,0,0,128,0,128,0,128,128,0,0,192,192,192,0,
                        192,220,192,0,240,202,166,0,212,240,255,0,177,226,255,0,142,212,255,0,107,198,255,0,
                        72,184,255,0,37,170,255,0,0,170,255,0,0,146,220,0,0,122,185,0,0,98,150,0,0,74,115,0,0,
                        50,80,0,212,227,255,0,177,199,255,0,142,171,255,0,107,143,255,0,72,115,255,0,37,87,255,0,0,
                        85,255,0,0,73,220,0,0,61,185,0,0,49,150,0,0,37,115,0,0,25,80,0,212,212,255,0,177,177,255,0,
                        142,142,255,0,107,107,255,0,72,72,255,0,37,37,255,0,0,0,254,0,0,0,220,0,0,0,185,0,0,0,150,0,
                        0,0,115,0,0,0,80,0,227,212,255,0,199,177,255,0,171,142,255,0,143,107,255,0,115,72,255,0,
                        87,37,255,0,85,0,255,0,73,0,220,0,61,0,185,0,49,0,150,0,37,0,115,0,25,0,80,0,240,212,255,0,
                        226,177,255,0,212,142,255,0,198,107,255,0,184,72,255,0,170,37,255,0,170,0,255,0,146,0,220,0,
                        122,0,185,0,98,0,150,0,74,0,115,0,50,0,80,0,255,212,255,0,255,177,255,0,255,142,255,0,255,107,255,0,
                        255,72,255,0,255,37,255,0,254,0,254,0,220,0,220,0,185,0,185,0,150,0,150,0,115,0,115,0,80,0,80,0,
                        255,212,240,0,255,177,226,0,255,142,212,0,255,107,198,0,255,72,184,0,255,37,170,0,255,0,170,0,
                        220,0,146,0,185,0,122,0,150,0,98,0,115,0,74,0,80,0,50,0,255,212,227,0,255,177,199,0,255,142,171,0,
                        255,107,143,0,255,72,115,0,255,37,87,0,255,0,85,0,220,0,73,0,185,0,61,0,150,0,49,0,115,0,37,0,
                        80,0,25,0,255,212,212,0,255,177,177,0,255,142,142,0,255,107,107,0,255,72,72,0,255,37,37,0,254,0,
                        0,0,220,0,0,0,185,0,0,0,150,0,0,0,115,0,0,0,80,0,0,0,255,227,212,0,255,199,177,0,255,171,142,0,
                        255,143,107,0,255,115,72,0,255,87,37,0,255,85,0,0,220,73,0,0,185,61,0,0,150,49,0,0,115,37,0,
                        0,80,25,0,0,255,240,212,0,255,226,177,0,255,212,142,0,255,198,107,0,255,184,72,0,255,170,37,0,
                        255,170,0,0,220,146,0,0,185,122,0,0,150,98,0,0,115,74,0,0,80,50,0,0,255,255,212,0,255,255,177,0,
                        255,255,142,0,255,255,107,0,255,255,72,0,255,255,37,0,254,254,0,0,220,220,0,0,185,185,0,0,150,150,0,
                        0,115,115,0,0,80,80,0,0,240,255,212,0,226,255,177,0,212,255,142,0,198,255,107,0,184,255,72,0,
                        170,255,37,0,170,255,0,0,146,220,0,0,122,185,0,0,98,150,0,0,74,115,0,0,50,80,0,0,227,255,212,0,
                        199,255,177,0,171,255,142,0,143,255,107,0,115,255,72,0,87,255,37,0,85,255,0,0,73,220,0,0,61,185,0,
                        0,49,150,0,0,37,115,0,0,25,80,0,0,212,255,212,0,177,255,177,0,142,255,142,0,107,255,107,0,72,255,72,0,
                        37,255,37,0,0,254,0,0,0,220,0,0,0,185,0,0,0,150,0,0,0,115,0,0,0,80,0,0,212,255,227,0,177,255,199,0,
                        142,255,171,0,107,255,143,0,72,255,115,0,37,255,87,0,0,255,85,0,0,220,73,0,0,185,61,0,0,150,49,0,0,
                        115,37,0,0,80,25,0,212,255,240,0,177,255,226,0,142,255,212,0,107,255,198,0,72,255,184,0,37,255,170,0,
                        0,255,170,0,0,220,146,0,0,185,122,0,0,150,98,0,0,115,74,0,0,80,50,0,212,255,255,0,177,255,255,0,
                        142,255,255,0,107,255,255,0,72,255,255,0,37,255,255,0,0,254,254,0,0,220,220,0,0,185,185,0,0,
                        150,150,0,0,115,115,0,0,80,80,0,242,242,242,0,230,230,230,0,218,218,218,0,206,206,206,0,194,194,194,0,
                        182,182,182,0,170,170,170,0,158,158,158,0,146,146,146,0,134,134,134,0,122,122,122,0,110,110,110,0,
                        98,98,98,0,86,86,86,0,74,74,74,0,62,62,62,0,50,50,50,0,38,38,38,0,26,26,26,0,14,14,14,0,240,251,255,0,
                        164,160,160,0,128,128,128,0,0,0,255,0,0,255,0,0,0,255,255,0,255,0,0,0,255,0,255,0,255,255,0,0,255,255,255,0};
                        memcpy(GetPalette(),pal256,1024);
                        break;
                }
        case 4:
                {
                        const BYTE pal16[64]={0,0,0,0,0,0,128,0,0,128,0,0,0,128,128,0,128,0,0,0,128,0,128,0,128,128,0,0,192,192,192,0,
                                                                128,128,128,0,0,0,255,0,0,255,0,0,0,255,255,0,255,0,0,0,255,0,255,0,255,255,0,0,255,255,255,0};
                        memcpy(GetPalette(),pal16,64);
                        break;
                }
        case 1:
                {
                        const BYTE pal2[8]={0,0,0,0,255,255,255,0};
                        memcpy(GetPalette(),pal2,8);
                        break;
                }
        }
        info.last_c_isvalid = false;
        return;
}
////////////////////////////////////////////////////////////////////////////////