source: trunk/src/gui/image/qbitmap.cpp@ 106

Last change on this file since 106 was 2, checked in by Dmitry A. Kuminov, 16 years ago

Initially imported qt-all-opensource-src-4.5.1 from Trolltech.

File size: 11.9 KB
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41
42#include "qbitmap.h"
43#include "qpixmapdata_p.h"
44#include "qimage.h"
45#include "qvariant.h"
46#include <qpainter.h>
47#include <private/qgraphicssystem_p.h>
48#include <private/qapplication_p.h>
49
50QT_BEGIN_NAMESPACE
51
52/*!
53 \class QBitmap
54 \brief The QBitmap class provides monochrome (1-bit depth) pixmaps.
55
56 \ingroup multimedia
57 \ingroup shared
58
59 The QBitmap class is a monochrome off-screen paint device used
60 mainly for creating custom QCursor and QBrush objects,
61 constructing QRegion objects, and for setting masks for pixmaps
62 and widgets.
63
64 QBitmap is a QPixmap subclass ensuring a depth of 1, except for
65 null objects which have a depth of 0. If a pixmap with a depth
66 greater than 1 is assigned to a bitmap, the bitmap will be
67 dithered automatically.
68
69 Use the QColor objects Qt::color0 and Qt::color1 when drawing on a
70 QBitmap object (or a QPixmap object with depth 1).
71
72 Painting with Qt::color0 sets the bitmap bits to 0, and painting
73 with Qt::color1 sets the bits to 1. For a bitmap, 0-bits indicate
74 background (or transparent pixels) and 1-bits indicate foreground
75 (or opaque pixels). Use the clear() function to set all the bits
76 to Qt::color0. Note that using the Qt::black and Qt::white colors
77 make no sense because the QColor::pixel() value is not necessarily
78 0 for black and 1 for white.
79
80 The QBitmap class provides the transformed() function returning a
81 transformed copy of the bitmap; use the QMatrix argument to
82 translate, scale, shear, and rotate the bitmap. In addition,
83 QBitmap provides the static fromData() function which returns a
84 bitmap constructed from the given \c uchar data, and the static
85 fromImage() function returning a converted copy of a QImage
86 object.
87
88 Just like the QPixmap class, QBitmap is optimized by the use of
89 implicit data sharing. For more information, see the {Implicit
90 Data Sharing} documentation.
91
92 \sa QPixmap, QImage, QImageReader, QImageWriter
93*/
94
95
96/*!
97 Constructs a null bitmap.
98
99 \sa QPixmap::isNull()
100*/
101
102QBitmap::QBitmap()
103 : QPixmap(QSize(0, 0), QPixmapData::BitmapType)
104{
105}
106
107/*!
108 \fn QBitmap::QBitmap(int width, int height)
109
110 Constructs a bitmap with the given \a width and \a height. The pixels
111 inside are uninitialized.
112
113 \sa clear()
114*/
115
116QBitmap::QBitmap(int w, int h)
117 : QPixmap(QSize(w, h), QPixmapData::BitmapType)
118{
119}
120
121/*!
122 Constructs a bitmap with the given \a size. The pixels in the
123 bitmap are uninitialized.
124
125 \sa clear()
126*/
127
128QBitmap::QBitmap(const QSize &size)
129 : QPixmap(size, QPixmapData::BitmapType)
130{
131}
132
133/*!
134 \fn QBitmap::clear()
135
136 Clears the bitmap, setting all its bits to Qt::color0.
137*/
138
139/*!
140 Constructs a bitmap that is a copy of the given \a pixmap.
141
142 If the pixmap has a depth greater than 1, the resulting bitmap
143 will be dithered automatically.
144
145 \sa QPixmap::depth(), fromImage(), fromData()
146*/
147
148QBitmap::QBitmap(const QPixmap &pixmap)
149{
150 QBitmap::operator=(pixmap);
151}
152
153/*!
154 \fn QBitmap::QBitmap(const QImage &image)
155
156 Constructs a bitmap that is a copy of the given \a image.
157
158 Use the static fromImage() function instead.
159*/
160
161/*!
162 Constructs a bitmap from the file specified by the given \a
163 fileName. If the file does not exist, or has an unknown format,
164 the bitmap becomes a null bitmap.
165
166 The \a fileName and \a format parameters are passed on to the
167 QPixmap::load() function. If the file format uses more than 1 bit
168 per pixel, the resulting bitmap will be dithered automatically.
169
170 \sa QPixmap::isNull(), QImageReader::imageFormat()
171*/
172
173QBitmap::QBitmap(const QString& fileName, const char *format)
174 : QPixmap(QSize(0, 0), QPixmapData::BitmapType)
175{
176 load(fileName, format, Qt::MonoOnly);
177}
178
179/*!
180 \overload
181
182 Assigns the given \a pixmap to this bitmap and returns a reference
183 to this bitmap.
184
185 If the pixmap has a depth greater than 1, the resulting bitmap
186 will be dithered automatically.