Starting from wxWidgets 2.5.0 wxImage supports alpha channel data, that is in
addition to a byte for the red, green and blue colour components for each pixel
-it also stores a byte representing the pixel opacity. The alpha value of $0$
-corresponds to a transparent pixel (null opacity) while the value of $255$
+it also stores a byte representing the pixel opacity. An alpha value of $0$
+corresponds to a transparent pixel (null opacity) while a value of $255$
means that the pixel is 100\% opaque.
-Unlike the RGB data, not all images have the alpha channel and before using
+Unlike RGB data, not all images have an alpha channel and before using
\helpref{GetAlpha}{wximagegetalpha} you should check if this image contains
-alpha value with \helpref{HasAlpha}{wximagehasalpha}. In fact, currently only
-images loaded from PNG files with transparency information will have alpha
-channel but support for it will be added to the other formats as well (as well
-as support for saving images with alpha channel which is not still implemented
-either).
+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).
\wxheading{Available image handlers}
Loads an image from an input stream.
+\func{}{wxImage}{\param{const char** }{xpmData}}
+
+Creates an image from XPM data.
+
\wxheading{Parameters}
\docparam{width}{Specifies the width of the image.}
"choose the default image" and is interpreted as the first image (index=0) by
the GIF and TIFF handler and as the largest and most colourful one by the ICO handler.}
+\docparam{xpmData}{A pointer to XPM image data.}
+
\wxheading{Remarks}
Depending on how wxWidgets has been configured, not all formats may be available.
Gets the red value of the mask colour.
+\membersection{wxImage::GetOrFindMaskColour}\label{wximagegetgetorsetmaskcolour}
+
+\constfunc{bool}{GetOrFindMaskColour}{\param{unsigned char}{ *r}, \param{unsigned char}{ *g}, \param{unsigned char}{ *b}}
+
+Get the current mask colour or find a suitable unused colour that could be
+used as a mask colour. Returns {\tt true} if the image currently has a mask.
+
+
\membersection{wxImage::GetPalette}\label{wximagegetpalette}
\constfunc{const wxPalette\&}{GetPalette}{\void}
\helpref{wxImage::HasOption}{wximagehasoption} is $0$ is a possibly valid value
for the option.
+Options for wxPNGHandler
+\twocolwidtha{5cm}%
+\begin{twocollist}
+\twocolitem{wxIMAGE\_OPTION\_PNG\_FORMAT}{Format for saving a PNG file.}
+\twocolitem{wxIMAGE\_OPTION\_PNG\_BITDEPTH}{Bit depth for every channel (R/G/B/A).}
+\end{twocollist}
+
+Supported values for wxIMAGE\_OPTION\_PNG\_FORMAT:
+\twocolwidtha{5cm}%
+\begin{twocollist}
+\twocolitem{wxPNG\_TYPE\_COLOUR}{Stores RGB image.}
+\twocolitem{wxPNG\_TYPE\_GREY}{Stores grey image, converts from RGB.}
+\twocolitem{wxPNG\_TYPE\_GREY\_RED}{Stores grey image, uses red value as grey.}
+\end{twocollist}
+
+
\wxheading{See also}
\helpref{wxImage::SetOption}{wximagesetoption},\rtfsp
\helpref{wxImage::GetOptionInt}{wximagegetoptionint}
+\membersection{wxImage::InitAlpha}\label{wximageinitalpha}
+
+\func{void}{InitAlpha}{\void}
+
+Initializes the image alpha channel data. It is an error to call it
+if the image already has alpha data. If it doesn't, alpha data will be
+by default initialized to all pixels being fully opaque. But if the image has a
+a mask colour, all mask pixels will be completely transparent.
+
+
\membersection{wxImage::InitStandardHandlers}\label{wximageinitstandardhandlers}
\func{static void}{InitStandardHandlers}{\void}
\func{wxImage \&}{Rescale}{\param{int}{ width}, \param{int}{ height}}
-Changes the size of the image in-place: after a call to this function, the
-image will have the given width and height.
+Changes the size of the image in-place by scaling it: after a call to this function,
+the image will have the given width and height.
Returns the (modified) image itself.
\helpref{Scale}{wximagescale}
+\membersection{wxImage::Resize}\label{wximageresize}
+
+\func{wxImage \&}{Resize}{\param{const wxSize\&}{ size}, \param{const wxPoint&}{ pos}, \param{int}{ red = -1}, \param{int}{ green = -1}, \param{int}{ blue = -1}}
+
+Changes the size of the image in-place without scaling it by adding either a border
+with the given colour or cropping as necessary. The image is pasted into a new
+image with the given {\it size} and background colour at the position {\it pos}
+relative to the upper left of the new image. If {\it red = green = blue = -1}
+then use either the current mask colour if set or find, use, and set a
+suitable mask colour for any newly exposed areas.
+
+Returns the (modified) image itself.
+
+\wxheading{See also}
+
+\helpref{Size}{wximagesize}
+
+
\membersection{wxImage::Rotate}\label{wximagerotate}
\func{wxImage}{Rotate}{\param{double}{ angle}, \param{const wxPoint\& }{rotationCentre},
\helpref{Rescale}{wximagerescale}
+\membersection{wxImage::Size}\label{wximagesize}
+
+\constfunc{wxImage}{Size}{\param{const wxSize\&}{ size}, \param{const wxPoint&}{ pos}, \param{int}{ red = -1}, \param{int}{ green = -1}, \param{int}{ blue = -1}}
+
+Returns a resized version of this image without scaling it by adding either a border
+with the given colour or cropping as necessary. The image is pasted into a new
+image with the given {\it size} and background colour at the position {\it pos}
+relative to the upper left of the new image. If {\it red = green = blue = -1}
+then use either the current mask colour if set or find, use, and set a
+suitable mask colour for any newly exposed areas.
+
+\wxheading{See also}
+
+\helpref{Resize}{wximageresize}
+
+
\membersection{wxImage::SetAlpha}\label{wximagesetalpha}
\func{void}{SetAlpha}{\param{unsigned char *}{alpha = {\tt NULL}}}
using the \helpref{GetData}{wximagegetdata} method.
+\membersection{wxImage::SetRGB}\label{wximagesetrgbrect}
+
+\func{void}{SetRGB}{\param{wxRect \& }{rect}, \param{unsigned char }{red}, \param{unsigned char }{green}, \param{unsigned char }{blue}}
+
+Sets the colour of the pixels within the given rectangle. This routine performs
+bounds-checks for the coordinate so it can be considered a safe way to manipulate the
+data.
+
+
\membersection{wxImage::operator $=$}\label{wximageassign}
\func{wxImage\& }{operator $=$}{\param{const wxImage\& }{image}}
projects / wxWidgets.git / blobdiff