X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/605d715ddd84ddc3e78423e3f3ae5c27c8ff4d43..e0eedd681816255e89d4cb5725003f479eeb4133:/docs/latex/wx/image.tex?ds=sidebyside diff --git a/docs/latex/wx/image.tex b/docs/latex/wx/image.tex index 2428ee35fb..6199e3ec2d 100644 --- a/docs/latex/wx/image.tex +++ b/docs/latex/wx/image.tex @@ -6,9 +6,37 @@ can be loaded from a file in a variety of formats, and is extensible to new form via image format handlers. Functions are available to set and get image bits, so it can be used for basic image manipulation. -A wxImage cannot (currently) be drawn directly to a wxDC. Instead, a platform-specific -wxBitmap object must be created from it, and that bitmap drawn on the wxDC, using -wxDC::DrawBitmap. +A wxImage cannot (currently) be drawn directly to a \helpref{wxDC}{wxdc}. Instead, +a platform-specific \helpref{wxBitmap}{wxbitmap} object must be created from it using +the \helpref{ConvertToBitmap}{wximageconverttobitmap} function. This bitmap can then +be drawn in a device context, using \helpref{wxDC::DrawBitmap}{wxdcdrawbitmap}. + +One colour value of the image may be used as a mask colour which will lead to the automatic +creation of a \helpref{wxMask}{wxmask} object associated to the bitmap object. + +\wxheading{Available image handlers} + +The following image handlers are available. {\bf wxBMPHandler} is always +installed by default. To use other image formats, install the appropiate +handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or +\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}. + +\twocolwidtha{5cm}% +\begin{twocollist} +\twocolitem{{\bf \indexit{wxBMPHandler}}}{Only for loading, always installed.} +\twocolitem{{\bf \indexit{wxPNGHandler}}}{For loading and saving.} +\twocolitem{{\bf \indexit{wxJPEGHandler}}}{For loading and saving.} +\twocolitem{{\bf \indexit{wxGIFHandler}}}{Only for loading, due to legal issues.} +\twocolitem{{\bf \indexit{wxPCXHandler}}}{For loading and saving (see below).} +\twocolitem{{\bf \indexit{wxPNMHandler}}}{For loading and saving (see below).} +\end{twocollist} + +When saving in PCX format, {\bf wxPCXHandler} will count the number of +different colours in the image; if there are 256 or less colours, it will +save as 8 bit, else it will save as 24 bit. + +Loading PNMs only works for ASCII or raw RGB images. When saving in +PNM format, {\bf wxPNMHandler} will always save as raw RGB. \wxheading{Derived from} @@ -45,13 +73,13 @@ and forth without loss in that respect. Creates an image with the given width and height. -\func{}{wxImage}{\param{const wxString\& }{name}, \param{long}{ type = wxBITMAP\_TYPE\_PNG}} +\func{}{wxImage}{\param{const wxString\& }{name}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}} \func{}{wxImage}{\param{const wxString\& }{name}, \param{const wxString\&}{ mimetype}} Loads an image from a file. -\func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{long}{ type = wxBITMAP\_TYPE\_PNG}} +\func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}} \func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{const wxString\&}{ mimetype}} @@ -77,6 +105,7 @@ Loads an image from an input stream. \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_GIF}}}{Load a GIF bitmap file.} \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PCX}}}{Load a PCX bitmap file.} \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PNM}}}{Load a PNM bitmap file.} +\twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_ANY}}}{Will try to autodetect the format.} \end{twocollist} The validity of these flags depends on the platform and wxWindows configuration. @@ -95,14 +124,14 @@ initialization in order to work with JPEGs. \pythonnote{Constructors supported by wxPython are:\par \indented{2cm}{\begin{twocollist} -\twocolitem{\bf{wxImage(name, flag)}}{Loads an image from a file} -\twocolitem{\bf{wxNullImage()}}{Create a null image (has no size or +\twocolitem{{\bf wxImage(name, flag)}}{Loads an image from a file} +\twocolitem{{\bf wxNullImage()}}{Create a null image (has no size or image data)} -\twocolitem{\bf{wxEmptyImage(width, height)}}{Creates an empty image +\twocolitem{{\bf wxEmptyImage(width, height)}}{Creates an empty image of the given size} -\twocolitem{\bf{wxImageFromMime(name, mimetype}}{Creates an image from +\twocolitem{{\bf wxImageFromMime(name, mimetype}}{Creates an image from the given file of the given mimetype} -\twocolitem{\bf{wxImageFromBitmap(bitmap)}}{Creates an image from a +\twocolitem{{\bf wxImageFromBitmap(bitmap)}}{Creates an image from a platform-dependent bitmap} \end{twocollist}} } @@ -126,7 +155,7 @@ of a given handler class in an application session.} \helpref{wxImageHandler}{wximagehandler} -\pythonnote{In wxPython this static method is named \tt{wxImage_AddHandler}.} +\pythonnote{In wxPython this static method is named {\tt wxImage_AddHandler}.} \membersection{wxImage::CleanUpHandlers} \func{static void}{CleanUpHandlers}{\void} @@ -142,9 +171,12 @@ This function is called by wxWindows on exit. Converts the image to a platform-specific bitmap object. This has to be done to actually display an image as you cannot draw an image directly on a window. The resulting bitmap will use the colour depth of the current system which entails -that a (crude) colour reduction has to take place. When in 8-bit mode, this -routine will use a color cube created on program start-up to look up colors. -Still, the image quality won't be perfect for photo images. +that a colour reduction has to take place. + +When in 8-bit mode (PseudoColour mode), the GTK port will use a color cube created +on program start-up to look up colors. This ensures a very fast conversion, but +the image quality won't be perfect (and could be better for photo images using more +sophisticated dithering algorithms). \membersection{wxImage::Create}\label{wximagecreate} @@ -264,7 +296,7 @@ Gets the red value of the mask colour. \membersection{wxImage::GetSubImage}\label{wximagegetsubimage} -\constfunc{wxImage}{GetSubImage}{\param{const wxRect\&}{rect}} +\constfunc{wxImage}{GetSubImage}{\param{const wxRect\&}{ rect}} Returns a sub image of the current one as long as the rect belongs entirely to the image. @@ -342,6 +374,7 @@ The meaning of {\it stream} data is determined by the {\it type} parameter.} \begin{twocollist} \twocolitem{{\bf wxBITMAP\_TYPE\_BMP}}{Load a Windows image file.} \twocolitem{{\bf wxBITMAP\_TYPE\_GIF}}{Load a GIF image file.} +\twocolitem{{\bf wxBITMAP\_TYPE\_TIF}}{Load a TIFF image file.} \twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Load a JPEG image file.} \twocolitem{{\bf wxBITMAP\_TYPE\_PCX}}{Load a PCX image file.} \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Load a PNG image file.} @@ -363,9 +396,9 @@ TRUE if the operation succeeded, FALSE otherwise. \pythonnote{In place of a single overloaded method name, wxPython implements the following methods:\par \indented{2cm}{\begin{twocollist} -\twocolitem{\bf{LoadFile(filename, type)}}{Loads an image of the given +\twocolitem{{\bf LoadFile(filename, type)}}{Loads an image of the given type from a file} -\twocolitem{\bf{LoadMimeFile(filename, mimetype)}}{Loads an image of the given +\twocolitem{{\bf LoadMimeFile(filename, mimetype)}}{Loads an image of the given mimetype from a file} \end{twocollist}} } @@ -414,12 +447,13 @@ Saves a image in the given stream. \docparam{stream}{An output stream. The meaning of {\it stream} is determined by the {\it type} parameter.} -\docparam{type}{Currently two types can be used: +\docparam{type}{Currently three types can be used: \twocolwidtha{5cm}% \begin{twocollist} \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Save a PNG image file.} \twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Save a JPEG image file.} +\twocolitem{{\bf wxBITMAP\_TYPE\_PCX}}{Save a PCX image file.} \end{twocollist} The validity of these flags depends on the platform and wxWindows configuration @@ -442,13 +476,20 @@ Depending on how wxWindows has been configured, not all formats may be available \pythonnote{In place of a single overloaded method name, wxPython implements the following methods:\par \indented{2cm}{\begin{twocollist} -\twocolitem{\bf{SaveFile(filename, type)}}{Saves the image using the given +\twocolitem{{\bf SaveFile(filename, type)}}{Saves the image using the given type to the named file} -\twocolitem{\bf{SaveMimeFile(filename, mimetype)}}{Saves the image using the given +\twocolitem{{\bf SaveMimeFile(filename, mimetype)}}{Saves the image using the given mimetype to the named file} \end{twocollist}} } +\membersection{wxImage::Replace}\label{wximagereplace} + +\func{void}{Replace}{\param{unsigned char}{ r1}, \param{unsigned char}{ g1}, \param{unsigned char}{ b1}, +\param{unsigned char}{ r2}, \param{unsigned char}{ g2}, \param{unsigned char}{ b2}} + +Replaces the colour specified by {\it r1,g1,b1} by the colour {\it r2,g2,b2}. + \membersection{wxImage::Rescale}\label{wximagerescale} \func{wxImage \&}{Rescale}{\param{int}{ width}, \param{int}{ height}} @@ -470,7 +511,7 @@ Returns a scaled version of the image. This is also useful for 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 post uses this function internally +It may be mentioned that the GTK port uses this function internally to scale bitmaps when using mapping mode in wxDC. Example: @@ -523,7 +564,8 @@ Sets the mask colour for this image (and tells the image to use the mask). Sets the pixel at the given coordinate. This routine performs bounds-checks for the coordinate so it can be considered a safe way to manipulate the data, but in some cases this might be too slow so that the data will have to -be set directly. In that case you have to get that data by calling GetData(). +be set directly. In that case you will have to get access to the image data +using the \helpref{GetData}{wximagegetdata} method. \membersection{wxImage::operator $=$}