Defer retrieval of LANG env var, too. No memory management

[wxWidgets.git] / docs / latex / wx / image.tex

diff --git a/docs/latex/wx/image.tex b/docs/latex/wx/image.tex
index 6eac4c09cd504e66992a5c984c3f81d9c57915f4..8325f4be631f8de1e581c93901d436d2b7615a57 100644 (file)
--- a/docs/latex/wx/image.tex
+++ b/docs/latex/wx/image.tex
@@ -7,12 +7,17 @@ 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
 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.
+wxBitmap object must be created from it, and that bitmap drawn on the wxDC, using
+wxDC::DrawBitmap.

 
 \wxheading{Derived from}
 
 \helpref{wxObject}{wxobject}
 
 
 \wxheading{Derived from}
 
 \helpref{wxObject}{wxobject}
 

+\wxheading{Include files}
+
+<wx/image.h>
+

 \wxheading{See also}
 
 \helpref{wxBitmap}{wxbitmap}
 \wxheading{See also}
 
 \helpref{wxBitmap}{wxbitmap}


@@ -31,7 +36,9 @@ Copy constructor.
 
 \func{}{wxImage}{\param{const wxBitmap\&}{ bitmap}}
 
 
 \func{}{wxImage}{\param{const wxBitmap\&}{ bitmap}}
 

-Constructs an image from a platform-dependent bitmap.
+Constructs an image from a platform-dependent bitmap. This preserves
+mask information so that bitmaps and images can be converted back
+and forth without loss in that respect.

 
 \func{}{wxImage}{\param{int}{ width}, \param{int}{ height}}
 
 
 \func{}{wxImage}{\param{int}{ width}, \param{int}{ height}}
 


@@ -39,8 +46,16 @@ 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\_PNG}}
 

+\func{}{wxImage}{\param{const wxString\& }{name}, \param{const wxString\&}{ mimetype}}
+

 Loads an image from a file.
 
 Loads an image from a file.
 

+\func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{long}{ type = wxBITMAP\_TYPE\_PNG}}
+
+\func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{const wxString\&}{ mimetype}}
+
+Loads an image from an input stream.
+

 \wxheading{Parameters}
 
 \docparam{width}{Specifies the width of the image.}
 \wxheading{Parameters}
 
 \docparam{width}{Specifies the width of the image.}


@@ -49,20 +64,26 @@ Loads an image from a file.
 
 \docparam{name}{This refers to an image filename. Its meaning is determined by the {\it type} parameter.}
 
 
 \docparam{name}{This refers to an image filename. Its meaning is determined by the {\it type} parameter.}
 

+\docparam{stream}{This refers to an input stream. Its meaning is determined by the {\it type} parameter. It is equal to loading from file except that you provide opened stream (file, HTTP or any other custom class).}
+

 \docparam{type}{May be one of the following:
 
 \docparam{type}{May be one of the following:
 

-\twocolwidtha{5cm}
+\twocolwidtha{5cm}%

 \begin{twocollist}
 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_BMP}}}{Load a Windows bitmap file.}
 \begin{twocollist}
 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_BMP}}}{Load a Windows bitmap file.}

-\twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_GIF}}}{Load a GIF bitmap file.}
-\twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_XBM}}}{Load an X bitmap file.}
-\twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_XPM}}}{Load an XPM bitmap file.}

 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PNG}}}{Load a PNG bitmap file.}
 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PNG}}}{Load a PNG bitmap file.}

+\twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_JPEG}}}{Load a JPEG bitmap file.}

 \end{twocollist}
 
 The validity of these flags depends on the platform and wxWindows configuration.
 \end{twocollist}
 
 The validity of these flags depends on the platform and wxWindows configuration.

-If all possible wxWindows settings are used, the Windows platform supports BMP, BMP\_RESOURCE,
-XPM\_DATA, and XPM. Under X, the available formats are BMP, GIF, XBM, and XPM.}
+If all possible wxWindows settings are used, the loading a BMP (Windows bitmap) file,
+a PNG (portable network graphics) file and a JPEG file is supported on all platforms that
+implement wxImage.}
+
+\docparam{mimetype}{MIME type string (for example 'image/jpeg')}
+
+Note : you must call wxImage::AddHandler(new wxJPEGHandler) during application 
+initialization in order to work with JPEGs.

 
 \wxheading{See also}
 
 
 \wxheading{See also}
 


@@ -99,7 +120,12 @@ This function is called by wxWindows on exit.
 
 \constfunc{wxBitmap}{ConvertToBitmap}{\void}
 
 
 \constfunc{wxBitmap}{ConvertToBitmap}{\void}
 

-Converts the image to a platform-specific bitmap object.
+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.

 
 \membersection{wxImage::Create}\label{wximagecreate}
 
 
 \membersection{wxImage::Create}\label{wximagecreate}
 


@@ -137,12 +163,18 @@ Finds the handler associated with the given extension and type.
 
 Finds the handler associated with the given image type.
 
 
 Finds the handler associated with the given image type.
 

+\func{static wxImageHandler*}{FindHandlerMime}{\param{const wxString\& }{mimetype}}
+
+Finds the handler associated with the given MIME type.
+

 \docparam{name}{The handler name.}
 
 \docparam{extension}{The file extension, such as ``bmp".}
 
 \docparam{imageType}{The image type, such as wxBITMAP\_TYPE\_BMP.}
 
 \docparam{name}{The handler name.}
 
 \docparam{extension}{The file extension, such as ``bmp".}
 
 \docparam{imageType}{The image type, such as wxBITMAP\_TYPE\_BMP.}
 

+\docparam{mimetype}{MIME type.}
+

 \wxheading{Return value}
 
 A pointer to the handler if found, NULL otherwise.
 \wxheading{Return value}
 
 A pointer to the handler if found, NULL otherwise.


@@ -161,7 +193,9 @@ Returns the blue intensity at the given coordinate.
 
 \constfunc{unsigned char*}{GetData}{\void}
 
 
 \constfunc{unsigned char*}{GetData}{\void}
 

-Returns the image data as an array.
+Returns the image data as an array. This is most often used when doing
+direct image manipulation. The return value points to an array of
+chararcters in RGBGBRGB... format.

 
 \membersection{wxImage::GetGreen}\label{wximagegetgreen}
 
 
 \membersection{wxImage::GetGreen}\label{wximagegetgreen}
 


@@ -230,7 +264,8 @@ Returns TRUE if there is a mask active, FALSE otherwise.
 \func{static void}{InitStandardHandlers}{\void}
 
 Adds the standard image format handlers, which, depending on wxWindows
 \func{static void}{InitStandardHandlers}{\void}
 
 Adds the standard image format handlers, which, depending on wxWindows

-configuration, can be handlers for Windows image, Windows image resource, and XPM.
+configuration, can be handlers for Windows BMP (loading), PNG
+(loading and saving) and JPEG (loading and saving) file formats.

 
 This function is called by wxWindows on startup.
 
 
 This function is called by wxWindows on startup.
 


@@ -255,26 +290,37 @@ of a given handler class in an application session.}
 
 \func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{long}{ type}}
 
 
 \func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{long}{ type}}
 

+\func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{const wxString\&}{ mimetype}}
+

 Loads an image from a file.
 
 Loads an image from a file.
 

+\func{bool}{LoadFile}{\param{wxInputStream\&}{ stream}, \param{long}{ type}}
+
+\func{bool}{LoadFile}{\param{wxInputStream\&}{ stream}, \param{const wxString\&}{ mimetype}}
+
+Loads an image from an input stream.
+

 \wxheading{Parameters}
 
 \docparam{name}{A filename.
 The meaning of {\it name} is determined by the {\it type} parameter.}
 
 \wxheading{Parameters}
 
 \docparam{name}{A filename.
 The meaning of {\it name} is determined by the {\it type} parameter.}
 

+\docparam{stream}{An input stream.
+The meaning of {\it stream} data is determined by the {\it type} parameter.}
+

 \docparam{type}{One of the following values:
 
 \docparam{type}{One of the following values:
 

-\twocolwidtha{5cm}
+\twocolwidtha{5cm}%

 \begin{twocollist}
 \twocolitem{{\bf wxBITMAP\_TYPE\_BMP}}{Load a Windows image file.}
 \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\_XBM}}{Load an X image file.}
-\twocolitem{{\bf wxBITMAP\_TYPE\_XPM}}{Load an XPM image file.}

 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Load a PNG image file.}
 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Load a PNG image file.}

+\twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Load a JPEG image file.}

 \end{twocollist}
 
 The validity of these flags depends on the platform and wxWindows configuration.}
 
 \end{twocollist}
 
 The validity of these flags depends on the platform and wxWindows configuration.}
 

+\docparam{mimetype}{MIME type string (for example 'image/jpeg')}
+

 \wxheading{Return value}
 
 TRUE if the operation succeeded, FALSE otherwise.
 \wxheading{Return value}
 
 TRUE if the operation succeeded, FALSE otherwise.


@@ -310,24 +356,34 @@ TRUE if the handler was found and removed, FALSE otherwise.
 
 \func{bool}{SaveFile}{\param{const wxString\& }{name}, \param{int}{ type}}
 
 
 \func{bool}{SaveFile}{\param{const wxString\& }{name}, \param{int}{ type}}
 

+\func{bool}{SaveFile}{\param{const wxString\& }{name}, \param{const wxString\&}{ mimetype}}
+

 Saves a image in the named file.
 
 Saves a image in the named file.
 

+\func{bool}{SaveFile}{\param{wxOutputStream\& }{stream}, \param{int}{ type}}
+
+\func{bool}{SaveFile}{\param{wxOutputStream\& }{stream}, \param{const wxString\&}{ mimetype}}
+
+Saves a image in the given stream.
+

 \wxheading{Parameters}
 
 \docparam{name}{A filename. The meaning of {\it name} is determined by the {\it type} parameter.}
 
 \wxheading{Parameters}
 
 \docparam{name}{A filename. The meaning of {\it name} is determined by the {\it type} parameter.}
 

-\docparam{type}{One of the following values:
+\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:

 
 

-\twocolwidtha{5cm}
+\twocolwidtha{5cm}%

 \begin{twocollist}
 \begin{twocollist}

-\twocolitem{{\bf wxBITMAP\_TYPE\_BMP}}{Save a Windows image file.}
-\twocolitem{{\bf wxBITMAP\_TYPE\_GIF}}{Save a GIF image file.}
-\twocolitem{{\bf wxBITMAP\_TYPE\_XBM}}{Save an X image file.}
-\twocolitem{{\bf wxBITMAP\_TYPE\_XPM}}{Save an XPM image file.}

 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Save a PNG image file.}
 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Save a PNG image file.}

+\twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Save a JPEG image file.}

 \end{twocollist}
 
 \end{twocollist}
 

-The validity of these flags depends on the platform and wxWindows configuration.}
+The validity of these flags depends on the platform and wxWindows configuration
+as well as user-added handlers.}
+
+\docparam{mimetype}{MIME type.}

 
 \wxheading{Return value}
 
 
 \wxheading{Return value}
 


@@ -345,13 +401,19 @@ Depending on how wxWindows has been configured, not all formats may be available
 
 \func{wxImage}{Scale}{\param{int}{ width}, \param{int}{ height}}
 
 
 \func{wxImage}{Scale}{\param{int}{ width}, \param{int}{ height}}
 

-Returns a scaled version of the image.
+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. Windows can do such 
+scaling itself but in the GTK port, scaling bitmaps is done using 
+this routine internally.

 
 \membersection{wxImage::SetData}\label{wximagesetdata}
 
 \func{void}{SetData}{\param{unsigned char*}{data}}
 
 
 \membersection{wxImage::SetData}\label{wximagesetdata}
 
 \func{void}{SetData}{\param{unsigned char*}{data}}
 

-Sets the image data.
+Sets the image data without performing checks. The data given must have 
+the size (width*height*3) or results will be unexpected. Don't use this
+method if you aren't sure you know what you are doing.

 
 \membersection{wxImage::SetMask}\label{wximagesetmask}
 
 
 \membersection{wxImage::SetMask}\label{wximagesetmask}
 


@@ -363,13 +425,16 @@ Specifies whether there is a mask or not. The area of the mask is determined by
 
 \func{void}{SetMaskColour}{\param{unsigned char }{red}, \param{unsigned char }{blue}, \param{unsigned char }{green}}
 
 
 \func{void}{SetMaskColour}{\param{unsigned char }{red}, \param{unsigned char }{blue}, \param{unsigned char }{green}}
 

-Sets the mask colour for this image.
+Sets the mask colour for this image (and tells the image to use the mask).

 
 \membersection{wxImage::SetRGB}\label{wximagesetrgb}
 
 \func{void}{SetRGB}{\param{int }{x}, \param{int }{y}, \param{unsigned char }{red}, \param{unsigned char }{blue}, \param{unsigned char }{green}}
 
 
 \membersection{wxImage::SetRGB}\label{wximagesetrgb}
 
 \func{void}{SetRGB}{\param{int }{x}, \param{int }{y}, \param{unsigned char }{red}, \param{unsigned char }{blue}, \param{unsigned char }{green}}
 

-Sets the pixel at the given coordinate.
+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().

 
 \membersection{wxImage::operator $=$}
 
 
 \membersection{wxImage::operator $=$}
 


@@ -419,8 +484,6 @@ Returns TRUE if the images were unequal, FALSE otherwise.
 
 \section{\class{wxImageHandler}}\label{wximagehandler}
 
 
 \section{\class{wxImageHandler}}\label{wximagehandler}
 

-\overview{Overview}{wximageoverview}
-

 This is the base class for implementing image file loading/saving, and image creation from data.
 It is used within wxImage and is not normally seen by the application.
 
 This is the base class for implementing image file loading/saving, and image creation from data.
 It is used within wxImage and is not normally seen by the application.
 


@@ -428,10 +491,21 @@ If you wish to extend the capabilities of wxImage, derive a class from wxImageHa
 and add the handler using \helpref{wxImage::AddHandler}{wximageaddhandler} in your
 application initialisation.
 
 and add the handler using \helpref{wxImage::AddHandler}{wximageaddhandler} in your
 application initialisation.
 

+\wxheading{Note (Legal Issue)}
+
+This software is based in part on the work of the Independent JPEG Group.
+
+(Applies when wxWindows is linked with JPEG support. wxJPEGHandler uses libjpeg
+created by IJG.)
+

 \wxheading{Derived from}
 
 \helpref{wxObject}{wxobject}
 
 \wxheading{Derived from}
 
 \helpref{wxObject}{wxobject}
 

+\wxheading{Include files}
+
+<wx/image.h>
+

 \wxheading{See also}
 
 \helpref{wxImage}{wximage}
 \wxheading{See also}
 
 \helpref{wxImage}{wximage}


@@ -469,18 +543,24 @@ Gets the file extension associated with this handler.
 
 Gets the image type associated with this handler.
 
 
 Gets the image type associated with this handler.
 

+\membersection{wxImageHandler::GetMimeType}
+
+\constfunc{wxString}{GetMimeType}{\void}
+
+Gets the MIME type associated with this handler.
+

 \membersection{wxImageHandler::LoadFile}\label{wximagehandlerloadfile}
 
 \membersection{wxImageHandler::LoadFile}\label{wximagehandlerloadfile}
 

-\func{bool}{LoadFile}{\param{wxImage* }{image}, \param{const wxString\&}{ name}}
+\func{bool}{LoadFile}{\param{wxImage* }{image}, \param{wxInputStream\&}{ stream}}

 
 

-Loads a image from a file or resource, putting the resulting data into {\it image}.
+Loads a image from a stream, putting the resulting data into {\it image}.

 
 \wxheading{Parameters}
 
 \docparam{image}{The image object which is to be affected by this operation.}
 
 
 \wxheading{Parameters}
 
 \docparam{image}{The image object which is to be affected by this operation.}
 

-\docparam{name}{Either a filename or a Windows resource name.
-The meaning of {\it name} is determined by the {\it type} parameter.}
+\docparam{stream}{Opened input stream.
+The meaning of {\it stream} is determined by the {\it type} parameter.}

 
 \wxheading{Return value}
 
 
 \wxheading{Return value}
 


@@ -494,15 +574,15 @@ TRUE if the operation succeeded, FALSE otherwise.
 
 \membersection{wxImageHandler::SaveFile}\label{wximagehandlersavefile}
 
 
 \membersection{wxImageHandler::SaveFile}\label{wximagehandlersavefile}
 

-\func{bool}{SaveFile}{\param{wxImage* }{image}, \param{const wxString\& }{name}}
+\func{bool}{SaveFile}{\param{wxImage* }{image}, \param{wxOutputStream\& }{stream}}

 
 

-Saves a image in the named file.
+Saves a image in the output stream.

 
 \wxheading{Parameters}
 
 \docparam{image}{The image object which is to be affected by this operation.}
 
 
 \wxheading{Parameters}
 
 \docparam{image}{The image object which is to be affected by this operation.}
 

-\docparam{name}{A filename. The meaning of {\it name} is determined by the {\it type} parameter.}
+\docparam{stream}{A stream. The meaning of {\it stream} is determined by the {\it type} parameter.}

 
 \wxheading{Return value}
 
 
 \wxheading{Return value}
 


@@ -545,3 +625,13 @@ Sets the handler type.
 \docparam{name}{Handler type.}
 
 
 \docparam{name}{Handler type.}
 
 

+\membersection{wxImageHandler::SetMimeType}
+
+\func{void}{SetMimeType}{\param{const wxString\& }{mimetype}}
+
+Sets the handler MIME type.
+
+\wxheading{Parameters}
+
+\docparam{mimename}{Handler MIME type.}
+