class QPicture¶

The QPicture class is a paint device that records and replays QPainter commands. More…

Synopsis¶

Methods¶

def __init__()
def boundingRect()
def data()
def isNull()
def load()
def play()
def save()
def setBoundingRect()
def size()
def swap()

Virtual methods¶

def setData()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description¶

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

A picture serializes painter commands to an IO device in a platform-independent format. They are sometimes referred to as meta-files.

Qt pictures use a proprietary binary format. Unlike native picture (meta-file) formats on many window systems, Qt pictures have no limitations regarding their contents. Everything that can be painted on a widget or pixmap (e.g., fonts, pixmaps, regions, transformed graphics, etc.) can also be stored in a picture.

QPicture is resolution independent, i.e. a QPicture can be displayed on different devices (for example svg, pdf, ps, printer and screen) looking the same. This is, for instance, needed for WYSIWYG print preview. QPicture runs in the default system dpi, and scales the painter to match differences in resolution depending on the window system.

Example of how to record a picture:

picture = QPicture()
painter = QPainter()
painter.begin(picture) # paint in picture
painter.drawEllipse(10,20, 80,70) # draw an ellipse
painter.end() # painting done
picture.save("drawing.pic") # save picture

Note that the list of painter commands is reset on each call to the begin() function.

Example of how to replay a picture:

picture = QPicture()
picture.load("drawing.pic") # load picture
painter = QPainter()
painter.begin(myImage) # paint in myImage
painter.drawPicture(0, 0, picture) # draw the picture at (0,0)
painter.end() # painting done

Pictures can also be drawn using play() . Some basic data about a picture is available, for example, size() , isNull() and boundingRect() .

See also

QMovie

__init__(arg__1)¶

Parameters:: arg__1 – QPicture

Constructs a copy of pic.

This constructor is fast thanks to implicit sharing.

__init__([formatVersion=-1])

Parameters:: formatVersion – int

Constructs an empty picture.

The formatVersion parameter may be used to create a QPicture that can be read by applications that are compiled with earlier versions of Qt.

Note that the default formatVersion is -1 which signifies the current release, i.e. for Qt 4.0 a formatVersion of 7 is the same as the default formatVersion of -1.

Reading pictures generated by earlier versions of Qt is not supported in Qt 4.0.

boundingRect()¶

Return type:: QRect

Returns the picture’s bounding rectangle or an invalid rectangle if the picture contains no data.

See also

setBoundingRect()

data()¶

Return type:: PyObject

Returns a pointer to the picture data. The pointer is only valid until the next non-const function is called on this picture. The returned pointer is 0 if the picture contains no data.

See also

setData() size() isNull()

isNull()¶

Return type:: bool

Returns true if the picture contains no data; otherwise returns false.

load(dev)¶

Parameters:: dev – QIODevice
Return type:: bool

This is an overloaded function.

dev is the device to use for loading.

load(fileName)

Parameters:: fileName – str
Return type:: bool

Loads a picture from the file specified by fileName and returns true if successful; otherwise invalidates the picture and returns false.

See also

save()

play(p)¶

Parameters:: p – QPainter
Return type:: bool

Replays the picture using painter, and returns true if successful; otherwise returns false.

This function does exactly the same as drawPicture() with (x, y) = (0, 0).

Note

The state of the painter isn’t preserved by this function.

save(dev)¶

Parameters:: dev – QIODevice
Return type:: bool

This is an overloaded function.

dev is the device to use for saving.

save(fileName)

Parameters:: fileName – str
Return type:: bool

Saves a picture to the file specified by fileName and returns true if successful; otherwise returns false.

See also

load()

setBoundingRect(r)¶

Parameters:: r – QRect

Sets the picture’s bounding rectangle to r. The automatically calculated value is overridden.

See also

boundingRect()

setData(data)¶

Parameters:: data – str

Sets the picture data directly from data and size. This function copies the input data.

See also

data() size()

size()¶

Return type:: int

Returns the size of the picture data.

See also

data()

swap(other)¶

Parameters:: other – QPicture

Swaps picture other with this picture. This operation is very fast and never fails.