Constructs a null pixmap.

See also

isNull()

Constructs a pixmap with the given width and height. If either width or height is zero then a null QPixmap is constructed.

This constructor will create a QPixmap with uninitialized data. The fill() method can be used to initialize the pixmap with an appropriate color before drawing onto it with QPainter.

See also

isNull()

Constructs a pixmap of the given size.

This constructor will create a QPixmap with uninitialized data. The fill() method can be used to initialize the pixmap with an appropriate color before drawing onto it with QPainter.

Constructs a pixmap from the file with the given fileName. If the file does not exist or is of an unknown format the pixmap becomes a null pixmap.

The loader attempts to read the pixmap using the specified format. If the format is not specified (which is the default), the loader probes the file for a header to guess the file format.

The file name can either refer to an actual file on disk or to one of the application's embedded resources. Refer to the Resource System overview for details on how to embed images and other resource files in the application's executable.

If the image needs to be modified to fit in a lower-resolution result (e.g. converting from 32-bit to 8-bit), use the flags to control the conversion.

The fileName, format and flags parameters are passed on to load(). This means that the data in fileName is not compiled into the binary. If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

Constructs a pixmap from the given xpm data, which must be a valid XPM image. Errors are silently ignored.

It is possible to make the XPM variable a bit more efficient bit by using an unusual declaration like the following:

The extra const makes the entire definition read-only, which is slightly more efficient (for example, when the code is in a shared library) and ROMable when the application is to be stored in ROM.

Constructs a pixmap that is a copy of the given pixmap.

See also

copy()

Destroys the pixmap.

Returns a number that identifies this QPixmap. Distinct QPixmap objects can only have the same cache key if they refer to the same contents.

The cacheKey() will change when the pixmap is altered.

Replaces this pixmap's data with the given image using the specified flags to control the conversion. The flags argument is a bitwise-OR of the Qt::ImageConversionFlags. Passing 0 for flags sets all the default options.

Returns true if the result is that this pixmap is not null.

See also

fromImage()

Returns a deep copy of the subset of the pixmap that is specified by the given rect. If the given rectangle is empty the whole image is copied. For more information refer to the Implicit Data Sharing documentation.

See also

operator=(), QPixmap()

Returns a deep copy of the subset of the pixmap that is specified by the rectangle QRect( x, y, width, height).

Creates and returns a heuristic mask for this pixmap.

The method works by selecting a color from one of the corners and then chipping away pixels of that color, starting at all the edges. If clipTight is true (the default) the mask is just large enough to cover the pixels; otherwise, the mask is larger than the data pixels.

The mask may not be perfect but it should be reasonable, so you can do things such as the following:

This method is slow because it involves converting to/from a QImage, and non-trivial computations.

See also

QImage::createHeuristicMask(), createMaskFromColor()

Creates and returns a mask for this pixmap based on the given maskColor. If the mode is Qt::MaskInColor, all pixels matching the maskColor will be transparent. If mode is Qt::MaskOutColor, all pixels matching the maskColor will be opaque.

This method is slow because it involves converting to/from a QImage.

See also

createHeuristicMask(), QImage::createMaskFromColor()

Returns the default pixmap depth used by the application.

On Windows and Mac, the default depth is always 32. On X11 and embedded, the depth of the screen will be returned by this function.

See also

depth(), QColormap::depth()

Returns the depth of the pixmap. The pixmap depth is also called bits per pixel (bpp) or bit planes of a pixmap. A null pixmap has a depth 0.

See also

defaultDepth()

Detaches the pixmap from shared pixmap data.

A pixmap is automatically detached by CopperSpice whenever its contents are about to change. This is done in almost all QPixmap member functions that modify the pixmap (fill(), fromImage(), load(), etc.), and in QPainter::begin() on a pixmap.

There are two exceptions in which detach() must be called explicitly, that is when calling the handle() or the x11PictureHandle() function (only available on X11). Otherwise, any modifications done using system calls, will be performed on the shared data.

The detach() function returns immediately if there is just a single reference or if the pixmap has not been initialized yet.

Returns the device pixel ratio for the pixmap. This is the ratio between "device pixels" and "device independent pixels". Use this method when calculating layout geometry based on the pixmap size. The default value is 1.0.

See also

setDevicePixelRatio(), QImageReader

Fills the current pixmap with the given fillColor. The effect of this method is undefined if the pixmap is currently being used as the target of a QPainter.

Fills the pixmap with the widget's background color or pixmap according to the given offset.

The QPoint offset defines a point in widget coordinates to which the pixmap's top-left pixel will be mapped to. This is only significant if the widget has a background pixmap, otherwise the pixmap will simply be filled with the background color of the widget.

Fills the pixmap with the widget's background color or pixmap. The given point, (xOffset, yOffset), defines an offset in widget coordinates to which the pixmap's top-left pixel will be mapped to.

Converts the given image to a pixmap using the specified flags to control the conversion. The flags argument is a bitwise-OR of the Qt::ImageConversionFlags. Passing 0 for flags sets all the default options.

In case of monochrome and 8-bit images, the image is first converted to a 32-bit pixmap and then filled with the colors in the color table. If this is too expensive an operation, you can use QBitmap::fromImage() instead.

See also

fromImageReader(), toImage()

Converts the given image to a pixmap without copying if possible.

Create a QPixmap from an image read directly from an imageReader. The flags argument is a bitwise-OR of the Qt::ImageConversionFlags. Passing 0 for flags sets all the default options.

On some systems, reading an image directly to QPixmap can use less memory than reading a QImage to convert it to QPixmap.

See also

fromImage(), toImage()

Creates a pixmap and paints the given widget, restricted by the given rect. If the widget has any children, then they are also painted in the appropriate positions. If no rectangle is specified (the default) the entire widget is painted.

If widget is a nullptr, the specified rectangle does not overlap the widget's rectangle, or an error occurs, the function will return a null QPixmap. If the rectangle is a superset of the given widget, the areas outside the widget are covered with the widget's background.

This function actually asks widget to paint itself (and its children to paint themselves) by calling paintEvent() with painter redirection turned on. But QPixmap also provides the grabWindow() function which is a bit faster by grabbing pixels directly off the screen. In addition, if there are overlaying windows, grabWindow(), unlike grabWidget(), will see them.

Warning

Do not grab a widget from its QWidget::paintEvent(). However, it is safe to grab a widget from another widget's paintEvent().

See also

grabWindow()

Creates a pixmap and paints the given widget, restricted by QRect(x, y, width, height), in it.

Warning

Do not grab a widget from its QWidget::paintEvent(). However, it is safe to grab a widget from another widget's paintEvent().

Creates and returns a pixmap constructed by grabbing the contents of the given window restricted by QRect(x, y, width, height).

The arguments (x, y) specify the offset in the window, whereas (width, height) specify the area to be copied. If width is negative this method copies everything to the right border of the window. If height is negative this method copies everything to the bottom of the window.

The window system identifier (WId) can be retrieved using the QWidget::winId() function. The rationale for using a window identifier and not a QWidget, is to enable grabbing of windows that are not part of the application, window system frames, and so on.

The grabWindow() function grabs pixels from the screen, not from the window, i.e. if there is another window partially or entirely over the one you grab, you get pixels from the overlying window, too. The mouse cursor is generally not grabbed.

Note on X11 that if the given window does not have the same depth as the root window, and another window partially or entirely obscures the one you grab, you will not get pixels from the overlying window. The contents of the obscured areas in the pixmap will be undefined and uninitialized.

On Windows Vista and above grabbing a layered window, which is created by setting the Qt::WA_TranslucentBackground attribute, will not work. Instead grabbing the desktop widget should work.

Warning

In general grabbing an area outside the screen is not safe. This depends on the underlying window system.

See also

grabWidget()

Returns the pixmap's handle to the device context.

QPixmap uses implicit data sharing. The detach() metho must be called explicitly to ensure only this pixmap's data is modified if the pixmap data is shared. A pixmap does not have an X11 handle unless created with fromX11Pixmap(), or if the native graphics system is explicitly enabled.

This method is X11 specific and using it is non-portable.

See also

detach()

Returns true if this pixmap has an alpha channel or has a mask, otherwise returns false.

See also

hasAlphaChannel(), mask()

Returns true if the pixmap has a format that respects the alpha channel, otherwise returns false.

See also

hasAlpha()

Returns the height of the pixmap.

See also

size()

Returns true if this is a null pixmap, otherwise returns false. A null pixmap has zero width, zero height and no contents. You can not draw in a null pixmap.

Returns true if this is a QBitmap, otherwise returns false.

Loads a pixmap from the file with the given fileName. Returns true if the pixmap was successfully loaded, otherwise returns false.

The loader attempts to read the pixmap using the specified format. If the format is not specified (which is the default), the loader probes the file for a header to guess the file format.

The file name can either refer to an actual file on disk or to one of the application's embedded resources. Refer to the Resource System overview for details on how to embed pixmaps and other resource files in the application's executable.

If the data needs to be modified to fit in a lower-resolution result (e.g. converting from 32-bit to 8-bit), use the flags to control the conversion.

QPixmaps are automatically added to the QPixmapCache when loaded from a file, the key used is internal and can not be acquired.

See also

loadFromData()

Loads a pixmap from the binary data using the specified format and conversion flags.

Loads a pixmap from the len first bytes of the given binary data. Returns true if the pixmap was loaded successfully, otherwise returns false.

The loader attempts to read the pixmap using the specified format. If the format is not specified (which is the default), the loader probes the file for a header to guess the file format.

If the data needs to be modified to fit in a lower-resolution result (e.g. converting from 32-bit to 8-bit), use the flags to control the conversion.

See also

load()

Extracts a bitmap mask from the pixmap's alpha channel. This can be an expensive operation.

See also

setMask()

Returns the metric information for the given paint device metric.

See also

PaintDeviceMetric

Reimplemented from QPaintDevice::metric()

Returns the pixmap as a QVariant.

Returns true if this is a null pixmap, otherwise returns false.

See also

isNull()

Copy assigns from other and returns a reference to this object.

See also

copy(), QPixmap()

Move assigns from other and returns a reference to this object.

Returns a pointer to the paint engine used for drawing on the device.

Implements QPaintDevice::paintEngine()

Returns the pixmap's enclosing rectangle.

Saves the pixmap to the file with the given fileName using the specified image file format and quality factor. If format is empty then an image format will be chosen from fileName's suffix. Returns true if successful, otherwise returns false.

The quality factor must be in the range [0,100] or -1. Specify 0 to obtain small compressed files, 100 for large uncompressed files, and -1 to use the default settings.

This method writes a QPixmap to the given device using the specified image file format and the quality factor. This can be used to save a pixmap directly into a QByteArray.

Scales the pixmap to the given size, using the aspectMode and transformMode. If the given size is empty this method returns a null pixmap.

• If aspectMode is Qt::IgnoreAspectRatio, the pixmap is scaled to size
• If aspectMode is Qt::KeepAspectRatio, the pixmap is scaled to a rectangle as large as possible inside size, preserving the aspect ratio
• If aspectMode is Qt::KeepAspectRatioByExpanding, the pixmap is scaled to a rectangle as small as possible outside size, preserving the aspect ratio

In some cases it can be more beneficial to draw the pixmap to a painter with a scale set rather than scaling the pixmap. This is the case when the painter is based on OpenGL or when the scale factor changes rapidly.

See also

isNull()

Returns a copy of the pixmap scaled to a rectangle with the given width and height according to the given aspectMode and transformMode. If either the width or the height is zero or negative, this method returns a null pixmap.

Returns a scaled copy of the image. The returned image is scaled to the given height using the specified transformMode. The width of the pixmap is automatically calculated so that the aspect ratio of the pixmap is preserved.

If height is 0 or negative, a null pixmap is returned.

See also

isNull()

Returns a scaled copy of the image. The returned image is scaled to the given width using the specified transformMode. The height of the pixmap is automatically calculated so that the aspect ratio of the pixmap is preserved.

If width is 0 or negative, a null pixmap is returned.

See also

isNull()

Scrolls the area rect of this pixmap by (dx, dy). The exposed region is left unchanged. You can optionally pass a pointer to an empty QRegion to get the region that is exposed by the scroll operation.

You can not scroll while there is an active painter on the pixmap.

See also

QWidget::scroll(), QGraphicsItem::scroll()

Equivalent to calling QPixmap::scroll(dx, dy, QRect(x, y, width, height), exposed).

See also

QWidget::scroll(), QGraphicsItem::scroll()

Sets the device pixel ratio for the pixmap. This is the ratio between image pixels and device-independent pixels. The default scaleFactor is 1.0.

Setting it to something else has two effects:

QPainters that are opened on the pixmap will be scaled. For example, painting on a 200x200 image if with a ratio of 2.0 will result in effective (device-independent) painting bounds of 100x100.

Methods in CopperSpice that calculate layout geometry based on the pixmap size will take the ratio into account. The net effect of this is that the pixmap is displayed as high DPI pixmap rather than a large pixmap.

See also

devicePixelRatio()

Sets a mask bitmap. This methods merges the mask with the pixmap's alpha channel. A pixel value of 1 on the mask means the pixmap's pixel is unchanged; a value of 0 means the pixel is transparent. The mask must have the same size as this pixmap. Setting a null mask resets the mask, leaving the previously transparent pixels black. The effect of this function is undefined when the pixmap is being painted on.

This can be an expensive operation.

See also

mask(), QBitmap

Returns the size of the pixmap.

See also

width(), height()

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

Converts the pixmap to a QImage. Returns a null image if the conversion fails.

If the pixmap has 1-bit depth, the returned image will also be 1 bit deep. Images with more bits will be returned in a format closely represents the underlying system. Usually this will be QImage::Format_ARGB32_Premultiplied for pixmaps with an alpha and QImage::Format_RGB32 or QImage::Format_RGB16 for pixmaps without alpha.

At this time the alpha masks on monochrome images are ignored.

See also

fromImage()

This convenience method converts the matrix into a QTransform and calls the overloaded method which takes a QTransform and a transformMode.

Returns a copy of the pixmap that is transformed using the given transformation transform and transformMode. The original pixmap is not changed.

The transformation is internally adjusted to compensate for unwanted translation; i.e. the pixmap produced is the smallest pixmap that contains all the transformed points of the original pixmap. Use the trueMatrix() function to retrieve the actual matrix used for transforming the pixmap.

This methods is slow because it involves a transformation to a QImage, non-trivial computations, and a transformation back to a QPixmap.

See also

trueMatrix()

This convenience method converts the matrix into a QTransform and calls the overloaded method which takes a QTransform, width, and height.

Returns the actual matrix used for transforming a pixmap with the given width, height, and matrix.

When transforming a pixmap using the transformed() function, the transformation matrix is internally adjusted to compensate for unwanted translation, i.e. transformed() returns the smallest pixmap containing all transformed points of the original pixmap. This function returns the modified matrix, which maps points correctly from the original pixmap into the new pixmap.

See also

transformed()

Returns the width of the pixmap.

See also

size()

Writes the pixmap to the stream and returns a reference to the stream. The image is written as a PNG image. Writing the stream to a file will not produce a valid image file.

Refer to Serializing Data Types for additional information.

See also

save()

Reads an image from the stream into the pixmap and returns a reference to the stream.

Refer to Serializing Data Types for additional information.

See also

QPixmap::load()