You should always use wxICON and wxBITMAP macros because they work for any
platform (unlike the code above which doesn't deal with wxMac, wxBe, ...) and
-are more short and clear than versions with {\tt #ifdef}s.
+are more short and clear than versions with {\tt \#ifdef}s.
\subsection{Supported bitmap file formats}\label{supportedbitmapformats}
The following lists the formats handled on different platforms. Note
-that missing or partially-implemented formats can be supplemented
-by using \helpref{wxImage}{wximage} to load the data, and then converting
-it to wxBitmap form.
+that missing or partially-implemented formats are automatically supplemented
+by the \helpref{wxImage}{wximage} to load the data, and then converting
+it to wxBitmap form. Note that using wxImage is the preferred way to
+load images in wxWindows, with the exception of resources (XPM-files or
+native Windows resources). Writing an image format handler for wxImage
+is also far easier than writing one for wxBitmap, because wxImage has
+exactly one format on all platforms whereas wxBitmap can store pixel data
+very differently, depending on colour depths and platform.
\wxheading{wxBitmap}
\begin{itemize}\itemsep=0pt
\item Windows bitmap resource (wxBITMAP\_TYPE\_BMP\_RESOURCE)
\item Windows bitmap file (wxBITMAP\_TYPE\_BMP)
-\item PNG file (wxBITMAP\_TYPE\_PNG). Currently 4-bit (16-colour) PNG files do not load properly.
\item XPM data and file (wxBITMAP\_TYPE\_XPM)
+\item All formats that are supported by the \helpref{wxImage}{wximage} class.
\end{itemize}
Under wxGTK, wxBitmap may load the following formats:
\begin{itemize}\itemsep=0pt
-\item Windows bitmap file (wxBITMAP\_TYPE\_BMP)
-\item PNG (wxBITMAP\_TYPE\_PNG).
\item XPM data and file (wxBITMAP\_TYPE\_XPM)
+\item All formats that are supported by the \helpref{wxImage}{wximage} class.
\end{itemize}
Under wxMotif, wxBitmap may load the following formats:
\begin{itemize}\itemsep=0pt
-%\item Windows bitmap file (wxBITMAP\_TYPE\_BMP)
-%\item PNG (wxBITMAP\_TYPE\_PNG).
\item XBM data and file (wxBITMAP\_TYPE\_XBM)
\item XPM data and file (wxBITMAP\_TYPE\_XPM)
+\item All formats that are supported by the \helpref{wxImage}{wximage} class.
\end{itemize}
\wxheading{wxIcon}
Under wxGTK, wxIcon may load the following formats:
\begin{itemize}\itemsep=0pt
-\item PNG (wxBITMAP\_TYPE\_PNG).
\item XPM data and file (wxBITMAP\_TYPE\_XPM)
+\item All formats that are supported by the \helpref{wxImage}{wximage} class.
\end{itemize}
Under wxMotif, wxIcon may load the following formats:
\begin{itemize}\itemsep=0pt
-%\item Windows bitmap file (wxBITMAP\_TYPE\_BMP)
-%\item PNG (wxBITMAP\_TYPE\_PNG).
\item XBM data and file (wxBITMAP\_TYPE\_XBM)
\item XPM data and file (wxBITMAP\_TYPE\_XPM)
+\item All formats that are supported by the \helpref{wxImage}{wximage} class (?).
\end{itemize}
\wxheading{wxCursor}
{\small
\begin{verbatim}
- #include <wx/pnghand.h>
#include <wx/xpmhand.h>
...
// Initialisation
- wxBitmap::AddHandler(new wxPNGFileHandler);
wxBitmap::AddHandler(new wxXPMFileHandler);
wxBitmap::AddHandler(new wxXPMDataHandler);
...
\end{verbatim}
}
-Assuming the handlers have been written correctly, you should now be able to load and save PNG files
-and XPM files using the usual wxBitmap API.
+Assuming the handlers have been written correctly, you should now be able to load and save
+XPM files using the usual wxBitmap API.
{\bf Note:} bitmap handlers are not implemented on all platforms. Currently, the above is only necessary on
Windows, to save the extra overhead of formats that may not be necessary (if you don't use them, they
-are not linked into the executable). Unix platforms have PNG and XPM capability built-in (where supported).
+are not linked into the executable). Unix platforms have XPM capability built-in (where supported).
+
+Also, just because a handler (such as a PNG handler) is not present does not mean that
+wxBitmap does not support that file format. If wxBitmap fails to find a suitable handler,
+the file-loading capabilities of wxImage are used instead.