Unlike RGB data, not all images have an alpha channel and before using
\helpref{GetAlpha}{wximagegetalpha} you should check if this image contains
-an alpha channel with \helpref{HasAlpha}{wximagehasalpha}. Note that currently only
-images loaded from PNG files with transparency information will have an alpha
-channel but alpha support will be added to the other formats as well (as well
-as support for saving images with alpha channel which also isn't implemented).
+an alpha channel with \helpref{HasAlpha}{wximagehasalpha}. Note that currently
+only the PNG format has full alpha channel support so only the images loaded
+from PNG files can have alpha and, if you initialize the image alpha channel
+yourself using \helpref{SetAlpha}{wximagesetalpha}, you should save it in PNG
+format to avoid losing it.
+
\wxheading{Available image handlers}
The following image handlers are available. {\bf wxBMPHandler} is always
installed by default. To use other image formats, install the appropriate
-handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or
+handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or call
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}.
\twocolwidtha{5cm}%
\twocolitem{\indexit{wxPCXHandler}}{For loading and saving (see below).}
\twocolitem{\indexit{wxPNMHandler}}{For loading and saving (see below).}
\twocolitem{\indexit{wxTIFFHandler}}{For loading and saving.}
+\twocolitem{\indexit{wxTGAHandler}}{For loading only.}
\twocolitem{\indexit{wxIFFHandler}}{For loading only.}
\twocolitem{\indexit{wxXPMHandler}}{For loading and saving.}
\twocolitem{\indexit{wxICOHandler}}{For loading and saving.}
\func{}{wxImage}{\param{const wxImage\& }{image}}
-Copy constructor.
+Copy constructor, uses \helpref{reference counting}{trefcount}.
\func{}{wxImage}{\param{const wxBitmap\&}{ bitmap}}
Loads an image from an input stream.
-\func{}{wxImage}{\param{const char** }{xpmData}}
+\func{}{wxImage}{\param{const char* const* }{xpmData}}
Creates an image from XPM data.
\twocolitem{\indexit{wxBITMAP\_TYPE\_PCX}}{Load a PCX bitmap file.}
\twocolitem{\indexit{wxBITMAP\_TYPE\_PNM}}{Load a PNM bitmap file.}
\twocolitem{\indexit{wxBITMAP\_TYPE\_TIF}}{Load a TIFF bitmap file.}
+\twocolitem{\indexit{wxBITMAP\_TYPE\_TGA}}{Load a TGA bitmap file.}
\twocolitem{\indexit{wxBITMAP\_TYPE\_XPM}}{Load a XPM bitmap file.}
\twocolitem{\indexit{wxBITMAP\_TYPE\_ICO}}{Load a Windows icon file (ICO).}
\twocolitem{\indexit{wxBITMAP\_TYPE\_CUR}}{Load a Windows cursor file (CUR).}
\func{}{\destruct{wxImage}}{\void}
Destructor.
+See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
\membersection{wxImage::AddHandler}\label{wximageaddhandler}
Example:
\begin{verbatim}
- wxFileDialog FileDlg( this, "Choose Image", ::wxGetCwd(), "", _("Image Files ") + wxImage::GetImageExtWildcard(), wxOPEN );
+ wxFileDialog FileDlg( this, "Choose Image", ::wxGetCwd(), "", _("Image Files ") + wxImage::GetImageExtWildcard(), wxFD_OPEN );
\end{verbatim}
\wxheading{See also}
-\membersection{wxImage::Ok}\label{wximageok}
+\membersection{wxImage::IsOk}\label{wximageisok}
-\constfunc{bool}{Ok}{\void}
+\constfunc{bool}{IsOk}{\void}
Returns true if image data is present.
scaling bitmaps in general as the only other way to scale bitmaps
is to blit a wxMemoryDC into another wxMemoryDC.
-It may be mentioned that the GTK port uses this function internally
-to scale bitmaps when using mapping modes in wxDC.
-
\docparam{quality}{Determines what method to use for resampling the image. Can be one of the following:
\twocolwidtha{5cm}%
\func{wxImage\& }{operator $=$}{\param{const wxImage\& }{image}}
-Assignment operator. This operator does not copy any data, but instead
-passes a pointer to the data in {\it image} and increments a reference
-counter. It is a fast operation.
+Assignment operator, using \helpref{reference counting}{trefcount}.
\wxheading{Parameters}
Returns 'this' object.
-\membersection{wxImage::operator $==$}\label{wximageequal}
-
-\constfunc{bool}{operator $==$}{\param{const wxImage\& }{image}}
-
-Equality operator. This operator tests whether the internal data pointers are
-equal (a fast test).
-
-\wxheading{Parameters}
-
-\docparam{image}{Image to compare with 'this'}
-
-\wxheading{Return value}
-
-Returns true if the images were effectively equal, false otherwise.
-
-
-\membersection{wxImage::operator $!=$}\label{wximagenotequal}
-
-\constfunc{bool}{operator $!=$}{\param{const wxImage\& }{image}}
-
-Inequality operator. This operator tests whether the internal data pointers are
-unequal (a fast test).
-
-\wxheading{Parameters}
-
-\docparam{image}{Image to compare with 'this'}
-
-\wxheading{Return value}
-
-Returns true if the images were unequal, false otherwise.
\section{\class{wxImageHandler}}\label{wximagehandler}
\membersection{wxImageHandler::GetName}\label{wximagehandlergetname}
-\constfunc{wxString}{GetName}{\void}
+\constfunc{const wxString\&}{GetName}{\void}
Gets the name of this handler.
\membersection{wxImageHandler::GetExtension}\label{wximagehandlergetextension}
-\constfunc{wxString}{GetExtension}{\void}
+\constfunc{const wxString\&}{GetExtension}{\void}
Gets the file extension associated with this handler.
\membersection{wxImageHandler::GetMimeType}\label{wximagehandlergetmimetype}
-\constfunc{wxString}{GetMimeType}{\void}
+\constfunc{const wxString\&}{GetMimeType}{\void}
Gets the MIME type associated with this handler.
projects / wxWidgets.git / blobdiff