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Diffstat (limited to 'src/opengl/qglcolormap.cpp')
-rw-r--r-- | src/opengl/qglcolormap.cpp | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/src/opengl/qglcolormap.cpp b/src/opengl/qglcolormap.cpp new file mode 100644 index 0000000..02a2c13 --- /dev/null +++ b/src/opengl/qglcolormap.cpp @@ -0,0 +1,287 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the QtOpenGL module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \class QGLColormap + \brief The QGLColormap class is used for installing custom colormaps into + QGLWidgets. + + \module OpenGL + \ingroup multimedia + \ingroup shared + + QGLColormap provides a platform independent way of specifying and + installing indexed colormaps into QGLWidgets. QGLColormap is + especially useful when using the OpenGL color-index mode. + + Under X11 you must use an X server that supports either a \c + PseudoColor or \c DirectColor visual class. If your X server + currently only provides a \c GrayScale, \c TrueColor, \c + StaticColor or \c StaticGray visual, you will not be able to + allocate colorcells for writing. If this is the case, try setting + your X server to 8 bit mode. It should then provide you with at + least a \c PseudoColor visual. Note that you may experience + colormap flashing if your X server is running in 8 bit mode. + + Under Windows the size of the colormap is always set to 256 + colors. Note that under Windows you can also install colormaps + in child widgets. + + This class uses \l{implicit sharing} as a memory and speed + optimization. + + Example of use: + \snippet doc/src/snippets/code/src_opengl_qglcolormap.cpp 0 + + \sa QGLWidget::setColormap(), QGLWidget::colormap() +*/ + +/*! + \fn Qt::HANDLE QGLColormap::handle() + + \internal + + Returns the handle for this color map. +*/ + +/*! + \fn void QGLColormap::setHandle(Qt::HANDLE handle) + + \internal + + Sets the handle for this color map to \a handle. +*/ + +#include "qglcolormap.h" + +QT_BEGIN_NAMESPACE + +QGLColormap::QGLColormapData QGLColormap::shared_null = { Q_BASIC_ATOMIC_INITIALIZER(1), 0, 0 }; + +/*! + Construct a QGLColormap. +*/ +QGLColormap::QGLColormap() + : d(&shared_null) +{ + d->ref.ref(); +} + + +/*! + Construct a shallow copy of \a map. +*/ +QGLColormap::QGLColormap(const QGLColormap &map) + : d(map.d) +{ + d->ref.ref(); +} + +/*! + Dereferences the QGLColormap and deletes it if this was the last + reference to it. +*/ +QGLColormap::~QGLColormap() +{ + if (!d->ref.deref()) + cleanup(d); +} + +void QGLColormap::cleanup(QGLColormap::QGLColormapData *x) +{ + delete x->cells; + x->cells = 0; + delete x; +} + +/*! + Assign a shallow copy of \a map to this QGLColormap. +*/ +QGLColormap & QGLColormap::operator=(const QGLColormap &map) +{ + map.d->ref.ref(); + if (!d->ref.deref()) + cleanup(d); + d = map.d; + return *this; +} + +/*! + \fn void QGLColormap::detach() + \internal + + Detaches this QGLColormap from the shared block. +*/ + +void QGLColormap::detach_helper() +{ + QGLColormapData *x = new QGLColormapData; + x->ref = 1; + x->cmapHandle = 0; + x->cells = 0; + if (d->cells) { + x->cells = new QVector<QRgb>(256); + *x->cells = *d->cells; + } + if (!d->ref.deref()) + cleanup(d); + d = x; +} + +/*! + Set cell at index \a idx in the colormap to color \a color. +*/ +void QGLColormap::setEntry(int idx, QRgb color) +{ + detach(); + if (!d->cells) + d->cells = new QVector<QRgb>(256); + d->cells->insert(idx, color); +} + +/*! + Set an array of cells in this colormap. \a count is the number of + colors that should be set, \a colors is the array of colors, and + \a base is the starting index. +*/ +void QGLColormap::setEntries(int count, const QRgb *colors, int base) +{ + detach(); + if (!d->cells) + d->cells = new QVector<QRgb>(256); + + Q_ASSERT_X(!colors || base >= 0 || base + count < d->cells->size(), "QGLColormap::setEntries", + "preconditions not met"); + for (int i = base; i < base + count; ++i) + setEntry(i, colors[i]); +} + +/*! + Returns the QRgb value in the colorcell with index \a idx. +*/ +QRgb QGLColormap::entryRgb(int idx) const +{ + if (d == &shared_null || !d->cells) + return 0; + else + return d->cells->at(idx); +} + +/*! + \overload + + Set the cell with index \a idx in the colormap to color \a color. +*/ +void QGLColormap::setEntry(int idx, const QColor &color) +{ + setEntry(idx, color.rgb()); +} + +/*! + Returns the QRgb value in the colorcell with index \a idx. +*/ +QColor QGLColormap::entryColor(int idx) const +{ + if (d == &shared_null || !d->cells) + return QColor(); + else + return QColor(d->cells->at(idx)); +} + +/*! + Returns true if the colormap is empty; otherwise returns false. A + colormap with no color values set is considered to be empty. +*/ +bool QGLColormap::isEmpty() const +{ + return d == &shared_null || d->cells == 0 || d->cells->size() == 0 || d->cmapHandle == 0; +} + + +/*! + Returns the number of colorcells in the colormap. +*/ +int QGLColormap::size() const +{ + return d->cells ? d->cells->size() : 0; +} + +/*! + Returns the index of the color \a color. If \a color is not in the + map, -1 is returned. +*/ +int QGLColormap::find(QRgb color) const +{ + if (d->cells) + return d->cells->indexOf(color); + return -1; +} + +/*! + Returns the index of the color that is the closest match to color + \a color. +*/ +int QGLColormap::findNearest(QRgb color) const +{ + int idx = find(color); + if (idx >= 0) + return idx; + int mapSize = size(); + int mindist = 200000; + int r = qRed(color); + int g = qGreen(color); + int b = qBlue(color); + int rx, gx, bx, dist; + for (int i = 0; i < mapSize; ++i) { + QRgb ci = d->cells->at(i); + rx = r - qRed(ci); + gx = g - qGreen(ci); + bx = b - qBlue(ci); + dist = rx * rx + gx * gx + bx * bx; // calculate distance + if (dist < mindist) { // minimal? + mindist = dist; + idx = i; + } + } + return idx; +} + +QT_END_NAMESPACE |