qcolormap_x11.cpp

奇趣公司比较新的qt/emd版本

    Display *display = QX11Info::display();
    const int screens = ScreenCount(display);

    cmaps = new QColormap*[screens];

    for (int i = 0; i < screens; ++i) {
        cmaps[i] = new QColormap;
        QColormapPrivate * const d = cmaps[i]->d;

        bool use_stdcmap = false;
        int color_count = X11->color_count;

        // defaults
        d->depth = DefaultDepth(display, i);
        d->colormap = DefaultColormap(display, i);
        d->defaultColormap = true;
        d->visual = DefaultVisual(display, i);
        d->defaultVisual = true;

        if (X11->visual && i == DefaultScreen(display)) {
            // only use the outside colormap on the default screen
            d->visual = find_visual(display, i, X11->visual->c_class,
                                    XVisualIDFromVisual(X11->visual),
                                    &d->depth, &d->defaultVisual);
        } else if ((X11->visual_class != -1 && X11->visual_class >= 0 && X11->visual_class < 6)
                   || (X11->visual_id != -1)) {
            // look for a specific visual or type of visual
            d->visual = find_visual(display, i, X11->visual_class, X11->visual_id,
                                    &d->depth, &d->defaultVisual);
        } else if (QApplication::colorSpec() == QApplication::ManyColor) {
            // look for a TrueColor w/ a depth higher than 8bpp
            d->visual = find_visual(display, i, TrueColor, -1, &d->depth, &d->defaultVisual);
            if (d->depth <= 8) {
                d->visual = DefaultVisual(display, i);
                d->defaultVisual = true;
                color_count = 216;
            }
        } else if (!X11->custom_cmap) {
            XStandardColormap *stdcmap = 0;
            int ncmaps = 0;
            if (XGetRGBColormaps(display, RootWindow(display, i),
                                 &stdcmap, &ncmaps, XA_RGB_DEFAULT_MAP)) {
                if (stdcmap) {
                    for (int c = 0; c < ncmaps; ++c) {
                        if (!stdcmap[c].red_max ||
                            !stdcmap[c].green_max ||
                            !stdcmap[c].blue_max ||
                            !stdcmap[c].red_mult ||
                            !stdcmap[c].green_mult ||
                            !stdcmap[c].blue_mult)
                            continue; // invalid stdcmap

                        XVisualInfo proto;
                        proto.visualid = stdcmap[c].visualid;
                        proto.screen = i;

                        int nvisuals = 0;
                        XVisualInfo *vi = XGetVisualInfo(display, VisualIDMask | VisualScreenMask,
                                                         &proto, &nvisuals);
                        if (vi) {
                            if (nvisuals > 0) {
                                use_stdcmap = true;

                                d->mode = ((vi[0].visual->c_class < StaticColor)
                                           ? Gray
                                           : ((vi[0].visual->c_class < TrueColor)
                                              ? Indexed
                                              : Direct));

                                d->depth = vi[0].depth;
                                d->colormap = stdcmap[c].colormap;
                                d->defaultColormap = true;
                                d->visual = vi[0].visual;
                                d->defaultVisual = (d->visual == DefaultVisual(display, i));

                                d->r_max = stdcmap[c].red_max   + 1;
                                d->g_max = stdcmap[c].green_max + 1;
                                d->b_max = stdcmap[c].blue_max  + 1;

                                if (d->mode == Direct) {
                                    // calculate offsets
                                    d->r_shift = lowest_bit(d->visual->red_mask);
                                    d->g_shift = lowest_bit(d->visual->green_mask);
                                    d->b_shift = lowest_bit(d->visual->blue_mask);
                                } else {
                                    d->r_shift = 0;
                                    d->g_shift = 0;
                                    d->b_shift = 0;
                                }
                            }
                            XFree(vi);
                        }
                        break;
                    }
                    XFree(stdcmap);
                }
            }
        }

        if (!use_stdcmap) {
            switch (d->visual->c_class) {
            case StaticGray:
                d->mode = Gray;

                d->r_max = d->g_max = d->b_max = d->visual->map_entries;
                break;

            case XGrayScale:
                d->mode = Gray;

                // follow precedent set in libXmu...
                if (color_count != 0)
                    d->r_max = d->g_max = d->b_max = color_count;
                else if (d->visual->map_entries > 65000)
                    d->r_max = d->g_max = d->b_max = 4096;
                else if (d->visual->map_entries > 4000)
                    d->r_max = d->g_max = d->b_max = 512;
                else if (d->visual->map_entries > 250)
                    d->r_max = d->g_max = d->b_max = 12;
                else
                    d->r_max = d->g_max = d->b_max = 4;
                break;

            case StaticColor:
                d->mode = Indexed;

                d->r_max = right_align(d->visual->red_mask)   + 1;
                d->g_max = right_align(d->visual->green_mask) + 1;
                d->b_max = right_align(d->visual->blue_mask)  + 1;
                break;

            case PseudoColor:
                d->mode = Indexed;

                // follow precedent set in libXmu...
                if (color_count != 0)
                    d->r_max = d->g_max = d->b_max = cube_root(color_count);
                else if (d->visual->map_entries > 65000)
                    d->r_max = d->g_max = d->b_max = 27;
                else if (d->visual->map_entries > 4000)
                    d->r_max = d->g_max = d->b_max = 12;
                else if (d->visual->map_entries > 250)
                    d->r_max = d->g_max = d->b_max = cube_root(d->visual->map_entries - 125);
                else
                    d->r_max = d->g_max = d->b_max = cube_root(d->visual->map_entries);
                break;

            case TrueColor:
            case DirectColor:
                d->mode = Direct;

                d->r_max = right_align(d->visual->red_mask)   + 1;
                d->g_max = right_align(d->visual->green_mask) + 1;
                d->b_max = right_align(d->visual->blue_mask)  + 1;

                d->r_shift = lowest_bit(d->visual->red_mask);
                d->g_shift = lowest_bit(d->visual->green_mask);
                d->b_shift = lowest_bit(d->visual->blue_mask);
                break;
            }
        }

        bool ownColormap = false;
        if (X11->colormap && i == DefaultScreen(display)) {
            // only use the outside colormap on the default screen
            d->colormap = X11->colormap;
            d->defaultColormap = (d->colormap == DefaultColormap(display, i));
        } else if (!use_stdcmap
                   && (((d->visual->c_class & 1) && X11->custom_cmap)
                       || d->visual != DefaultVisual(display, i))
                       || d->visual->c_class == DirectColor) {
            // allocate custom colormap (we always do this when using DirectColor visuals)
            d->colormap =
                XCreateColormap(display, RootWindow(display, i), d->visual,
                                d->visual->c_class == DirectColor ? AllocAll : AllocNone);
            d->defaultColormap = false;
            ownColormap = true;
        }

        switch (d->mode) {
        case Gray:
            init_gray(d, i);
            break;
        case Indexed:
            init_indexed(d, i);
            break;
        case Direct:
            init_direct(d, ownColormap);
            break;
        }

        QX11InfoData *screen = X11->screens + i;
        screen->depth = d->depth;
        screen->visual = d->visual;
        screen->defaultVisual = d->defaultVisual;
        screen->colormap = d->colormap;
        screen->defaultColormap = d->defaultColormap;
        screen->cells = screen->visual->map_entries;

        // ###
        // We assume that 8bpp == pseudocolor, but this is not
        // always the case (according to the X server), so we need
        // to make sure that our internal data is setup in a way
        // that is compatible with our assumptions
        if (screen->visual->c_class == TrueColor && screen->depth == 8 && screen->cells == 8)
            screen->cells = 256;
    }
}

/*! \internal
*/
void QColormap::cleanup()
{
    Display *display = QX11Info::display();
    const int screens = ScreenCount(display);

    for (int i = 0; i < screens; ++i)
        delete cmaps[i];

    delete [] cmaps;
    cmaps = 0;
}

/*!
    Returns the colormap for the specified \a screen.  If \a screen is
    -1, this function returns the colormap for the default screen.
*/
QColormap QColormap::instance(int screen)
{
    if (screen == -1)
        screen = QX11Info::appScreen();
    return *cmaps[screen];
}

/*! \internal
    Constructs a new colormap.
*/
QColormap::QColormap()
    : d(new QColormapPrivate)
{}

/*!
    Constructs a copy of another \a colormap.
 */
QColormap::QColormap(const QColormap &colormap)
    :d (colormap.d)
{ d->ref.ref(); }

/*!
    Destroys the colormap.
*/
QColormap::~QColormap()
{
    if (!d->ref.deref()) {
        if (!d->defaultColormap)
            XFreeColormap(QX11Info::display(), d->colormap);
        delete d;
    }
}

/*!
    Returns the mode of this colormap.

    \sa QColormap::Mode
*/
QColormap::Mode QColormap::mode() const
{ return d->mode; }

/*!
    Returns the depth of the device.

    \sa size()
*/
int QColormap::depth() const
{ return d->depth; }

/*!
    Returns the size of the colormap for \c Indexed and \c Gray modes;
    Returns -1 for \c Direct mode.

    \sa colormap()
*/
int QColormap::size() const
{
    return (d->mode == Gray
            ? d->r_max
            : (d->mode == Indexed
               ? d->r_max * d->g_max * d->b_max
               : -1));
}

/*!
    Returns a device dependent pixel value for the \a color.

    \sa colorAt()
*/
uint QColormap::pixel(const QColor &color) const
{
    const QColor c = color.toRgb();
    const uint r = (c.ct.argb.red   * d->r_max) >> 16;
    const uint g = (c.ct.argb.green * d->g_max) >> 16;
    const uint b = (c.ct.argb.blue  * d->b_max) >> 16;
    if (d->mode != Direct) {
        if (d->mode == Gray)
            return d->pixels.at((r * 30 + g * 59 + b * 11) / 100);
        return d->pixels.at(r * d->g_max * d->b_max + g * d->b_max + b);
    }
    return (r << d->r_shift) + (g << d->g_shift) + (b << d->b_shift);
}

/*!
    Returns a QColor for the \a pixel.

    \sa pixel()
*/
const QColor QColormap::colorAt(uint pixel) const
{
    if (d->mode != Direct) {
        Q_ASSERT(pixel <= (uint)d->colors.size());
        return d->colors.at(pixel);
    }

    const int r = (((pixel & d->visual->red_mask)   >> d->r_shift) << 8) / d->r_max;
    const int g = (((pixel & d->visual->green_mask) >> d->g_shift) << 8) / d->g_max;
    const int b = (((pixel & d->visual->blue_mask)  >> d->b_shift) << 8) / d->b_max;
    return QColor(r, g, b);
}

/*!
    Returns a vector of colors which represents the devices colormap
    for \c Indexed and \c Gray modes.  This function returns an empty
    vector for \c Direct mode.

    \sa size()
*/
const QVector<QColor> QColormap::colormap() const
{ return d->colors; }

/*! \fn HPALETTE QColormap::hPal()

    This function is only available on Windows.

    Returns an handle to the HPALETTE used by this colormap.  If no
    HPALETTE is being used, this function returns zero.
*/


/*! \since 4.2
    \fn QColormap &QColormap::operator=(const QColormap &colormap)

    Assigns the given \a colormap to \e this color map and returns
    a reference to \e this color map.
*/
QColormap &QColormap::operator=(const QColormap &colormap)
{
    qAtomicAssign(d, colormap.d);
    return *this;
}