kpixmap.cpp

/*
 *  This file is part of the KDE libraries
 *  Copyright (C) 1998  Mark Donohoe <donohoe@kde.org>
 *          Stephan Kulow <coolo@kde.org>
 *
 *  $Id$
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Library General Public License for more details.
 *
 *  You should have received a copy of the GNU Library General Public License
 *  along with this library; see the file COPYING.LIB.  If not, write to
 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301, USA.
 */
 
#include <tqpixmap.h>
#include <tqpainter.h>
#include <tqimage.h>
#include <tqbitmap.h>
#include <tqcolor.h>
 
#include <stdlib.h>
#include "kpixmap.h"
 
// Fast diffuse dither to 3x3x3 color cube
// Based on Qt's image conversion functions
static bool kdither_32_to_8( const TQImage *src, TQImage *dst )
{
    // TQRgb *p;
    uchar  *b;
    int     y;
    
    if ( !dst->create(src->width(), src->height(), 8, 256) ) {
    tqWarning("KPixmap: destination image not valid\n");
    return false;
    }
 
    dst->setNumColors( 256 );
 
#define MAX_R 2
#define MAX_G 2
#define MAX_B 2
#define INDEXOF(r,g,b) (((r)*(MAX_G+1)+(g))*(MAX_B+1)+(b))
 
    int rc, gc, bc;
 
    for ( rc=0; rc<=MAX_R; rc++ )       // build 2x2x2 color cube
        for ( gc=0; gc<=MAX_G; gc++ )
        for ( bc=0; bc<=MAX_B; bc++ ) {
        dst->setColor( INDEXOF(rc,gc,bc),
        tqRgb( rc*255/MAX_R, gc*255/MAX_G, bc*255/MAX_B ) );
        }   
 
    int sw = src->width();
    int* line1[3];
    int* line2[3];
    int* pv[3];
 
    line1[0] = new int[src->width()];
    line2[0] = new int[src->width()];
    line1[1] = new int[src->width()];
    line2[1] = new int[src->width()];
    line1[2] = new int[src->width()];
    line2[2] = new int[src->width()];
    pv[0] = new int[sw];
    pv[1] = new int[sw];
    pv[2] = new int[sw];
 
    for ( y=0; y < src->height(); y++ ) {
    // p = (TQRgb *)src->scanLine(y);
    b = dst->scanLine(y);
    int endian = (TQImage::systemBitOrder() == TQImage::BigEndian);
    int x;
    uchar* q = const_cast<TQImage*>(src)->scanLine(y);
    uchar* q2 = const_cast<TQImage*>(src)->scanLine(y+1 < src->height() ? y + 1 : 0);
 
    for (int chan = 0; chan < 3; chan++) {
        b = dst->scanLine(y);
        int *l1 = (y&1) ? line2[chan] : line1[chan];
        int *l2 = (y&1) ? line1[chan] : line2[chan];
        if ( y == 0 ) {
        for (int i=0; i<sw; i++)
            l1[i] = q[i*4+chan+endian];
        }
        if ( y+1 < src->height() ) {
        for (int i=0; i<sw; i++)
            l2[i] = q2[i*4+chan+endian];
        }
 
        // Bi-directional error diffusion
        if ( y&1 ) {
        for (x=0; x<sw; x++) {
            int pix = TQMAX(TQMIN(2, (l1[x] * 2 + 128)/ 255), 0);
            int err = l1[x] - pix * 255 / 2;
            pv[chan][x] = pix;
 
            // Spread the error around...
            if ( x+1<sw ) {
            l1[x+1] += (err*7)>>4;
            l2[x+1] += err>>4;
            }
            l2[x]+=(err*5)>>4;
            if (x>1)
            l2[x-1]+=(err*3)>>4;
        }
        } else {
        for (x=sw; x-->0; ) {
            int pix = TQMAX(TQMIN(2, (l1[x] * 2 + 128)/ 255), 0);
            int err = l1[x] - pix * 255 / 2;
            pv[chan][x] = pix;
 
            // Spread the error around...
            if ( x > 0 ) {
            l1[x-1] += (err*7)>>4;
            l2[x-1] += err>>4;
            }
            l2[x]+=(err*5)>>4;
            if (x+1 < sw)
            l2[x+1]+=(err*3)>>4;
        }
        }
    }
 
    if (!endian) {
        for (x=0; x<sw; x++)
        *b++ = INDEXOF(pv[2][x],pv[1][x],pv[0][x]);
    } else {
        for (x=0; x<sw; x++)
        *b++ = INDEXOF(pv[0][x],pv[1][x],pv[2][x]);
    }
 
    }
 
    delete [] line1[0];
    delete [] line2[0];
    delete [] line1[1];
    delete [] line2[1];
    delete [] line1[2];
    delete [] line2[2];
    delete [] pv[0];
    delete [] pv[1];
    delete [] pv[2];
    
#undef MAX_R
#undef MAX_G
#undef MAX_B
#undef INDEXOF
 
    return true;
}
 
KPixmap::~KPixmap()
{
}
 
bool KPixmap::load( const TQString& fileName, const char *format,
            int conversion_flags )
{
    TQImageIO io( fileName, format );
 
    bool result = io.read();
    
    if ( result ) {
    detach();
    result = convertFromImage( io.image(), conversion_flags );
    }
    return result;
}
 
bool KPixmap::load( const TQString& fileName, const char *format,
            ColorMode mode )
{
    int conversion_flags = 0;
    switch (mode) {
    case Color:
    conversion_flags |= ColorOnly;
    break;
    case Mono:
    conversion_flags |= MonoOnly;
    break;
    case LowColor:
    conversion_flags |= LowOnly;
    break;
    case WebColor:
    conversion_flags |= WebOnly;
    break;
    default:
    break;// Nothing.
    }
    return load( fileName, format, conversion_flags );
}
 
bool KPixmap::convertFromImage( const TQImage &img, ColorMode mode )
{
    int conversion_flags = 0;
    switch (mode) {
    case Color:
    conversion_flags |= ColorOnly;
    break;
    case Mono:
    conversion_flags |= MonoOnly;
    break;
    case LowColor:
    conversion_flags |= LowOnly;
    break;
    case WebColor:
    conversion_flags |= WebOnly;
    break;
    default:
    break;  // Nothing.
    }
    return convertFromImage( img, conversion_flags );
}
 
bool KPixmap::convertFromImage( const TQImage &img, int conversion_flags  )
{
    if ( img.isNull() ) {
#if defined(CHECK_NULL)
    tqWarning( "KPixmap::convertFromImage: Cannot convert a null image" );
#endif
    return false;
    }
    detach();                   // detach other references
    
    int dd = defaultDepth();
 
    // If color mode not one of KPixmaps extra modes nothing to do
    if ( ( conversion_flags & KColorMode_Mask ) != LowOnly &&
     ( conversion_flags & KColorMode_Mask ) != WebOnly ) {
        return TQPixmap::convertFromImage ( img, conversion_flags );
    }
 
    // If the default pixmap depth is not 8bpp, KPixmap color modes have no
    // effect. Ignore them and use AutoColor instead.
    if ( dd > 8 ) {
    if ( ( conversion_flags & KColorMode_Mask ) == LowOnly ||
         ( conversion_flags & KColorMode_Mask ) == WebOnly )
        conversion_flags = (conversion_flags & ~KColorMode_Mask) | Auto;
    return TQPixmap::convertFromImage ( img, conversion_flags );
    }
    
    if ( ( conversion_flags & KColorMode_Mask ) == LowOnly ) {
    // Here we skimp a little on the possible conversion modes
    // Don't offer ordered or threshold dither of RGB channels or
    // diffuse or ordered dither of alpha channel. It hardly seems
    // worth the effort for this specialized mode.
    
    // If image uses icon palette don't dither it.
    if( img.numColors() > 0 && img.numColors() <=40 ) {
        if ( checkColorTable( img ) )
        return TQPixmap::convertFromImage( img, TQPixmap::Auto );
    }
    
    TQBitmap mask;
    bool isMask = false;
 
    TQImage  image = img.convertDepth(32);
    TQImage tImage( image.width(), image.height(), 8, 256 );
    
    if( img.hasAlphaBuffer() ) {
        image.setAlphaBuffer( true );
        tImage.setAlphaBuffer( true );
        isMask = mask.convertFromImage( img.createAlphaMask() );
    }
    
    kdither_32_to_8( &image, &tImage );
        
    if( TQPixmap::convertFromImage( tImage ) ) {
        if ( isMask ) TQPixmap::setMask( mask );
        return true;
    } else
        return false;
    } else {
    TQImage  image = img.convertDepth( 32 );
    image.setAlphaBuffer( img.hasAlphaBuffer() );
    conversion_flags = (conversion_flags & ~ColorMode_Mask) | Auto;
    return TQPixmap::convertFromImage ( image, conversion_flags );
    }
}
 
static TQColor* kpixmap_iconPalette = 0;
 
bool KPixmap::checkColorTable( const TQImage &image )
{
    int i = 0;
 
    if (kpixmap_iconPalette == 0) {
    kpixmap_iconPalette = new TQColor[40];
    
    // Standard palette
    kpixmap_iconPalette[i++] = red;
    kpixmap_iconPalette[i++] = green;
    kpixmap_iconPalette[i++] = blue;
    kpixmap_iconPalette[i++] = cyan;
    kpixmap_iconPalette[i++] = magenta;
    kpixmap_iconPalette[i++] = yellow;
    kpixmap_iconPalette[i++] = darkRed;
    kpixmap_iconPalette[i++] = darkGreen;
    kpixmap_iconPalette[i++] = darkBlue;
    kpixmap_iconPalette[i++] = darkCyan;
    kpixmap_iconPalette[i++] = darkMagenta;
    kpixmap_iconPalette[i++] = darkYellow;
    kpixmap_iconPalette[i++] = white;
    kpixmap_iconPalette[i++] = lightGray;
    kpixmap_iconPalette[i++] = gray;
    kpixmap_iconPalette[i++] = darkGray;
    kpixmap_iconPalette[i++] = black;
    
    // Pastels
    kpixmap_iconPalette[i++] = TQColor( 255, 192, 192 );
    kpixmap_iconPalette[i++] = TQColor( 192, 255, 192 );
    kpixmap_iconPalette[i++] = TQColor( 192, 192, 255 );
    kpixmap_iconPalette[i++] = TQColor( 255, 255, 192 );
    kpixmap_iconPalette[i++] = TQColor( 255, 192, 255 );
    kpixmap_iconPalette[i++] = TQColor( 192, 255, 255 );
 
    // Reds
    kpixmap_iconPalette[i++] = TQColor( 64,   0,   0 );
    kpixmap_iconPalette[i++] = TQColor( 192,  0,   0 );
 
    // Oranges
    kpixmap_iconPalette[i++] = TQColor( 255, 128,   0 );
    kpixmap_iconPalette[i++] = TQColor( 192,  88,   0 );
    kpixmap_iconPalette[i++] = TQColor( 255, 168,  88 );
    kpixmap_iconPalette[i++] = TQColor( 255, 220, 168 );
 
    // Blues
    kpixmap_iconPalette[i++] = TQColor(   0,   0, 192 );
 
    // Turquoise
    kpixmap_iconPalette[i++] = TQColor(   0,  64,  64 );
    kpixmap_iconPalette[i++] = TQColor(   0, 192, 192 );
 
    // Yellows
    kpixmap_iconPalette[i++] = TQColor(  64,  64,   0 );
    kpixmap_iconPalette[i++] = TQColor( 192, 192,   0 );
 
    // Greens
    kpixmap_iconPalette[i++] = TQColor(   0,  64,   0 );
    kpixmap_iconPalette[i++] = TQColor(   0, 192,   0 );
 
    // Purples
    kpixmap_iconPalette[i++] = TQColor( 192,   0, 192 );
 
    // Greys
    kpixmap_iconPalette[i++] = TQColor(  88,  88,  88 );
    kpixmap_iconPalette[i++] = TQColor(  48,  48,  48 );
    kpixmap_iconPalette[i++] = TQColor( 220, 220, 220 );
    
    }
 
    TQRgb* ctable = image.colorTable();
 
    int ncols = image.numColors();
    int j;
 
    // Allow one failure which could be transparent background
    int failures = 0;
 
    for ( i=0; i<ncols; i++ ) {
    for ( j=0; j<40; j++ ) {
        if ( kpixmap_iconPalette[j].red() == tqRed( ctable[i] ) &&
         kpixmap_iconPalette[j].green() == tqGreen( ctable[i] ) &&
         kpixmap_iconPalette[j].blue() == tqBlue( ctable[i] ) ) {
        break;
        }
    }
    
    if ( j == 40 ) {
        failures ++;            
    }
    }
 
    return ( failures <= 1 );
 
}
 
KPixmap::KPixmap(const TQPixmap& p)
    : TQPixmap(p)
{
}