wxBitmap - Functions for wxBitmap class
Please see following description for synopsis
wxBitmap(3) Erlang Module Definition wxBitmap(3)
NAME
wxBitmap - Functions for wxBitmap class
DESCRIPTION
This class encapsulates the concept of a platform-dependent bitmap,
either monochrome or colour or colour with alpha channel support.
If you need direct access the bitmap data instead going through drawing
to it using wxMemoryDC you need to use the wxPixelData (not implemented
in wx) class (either wxNativePixelData for RGB bitmaps or wxAlphaPixel-
Data for bitmaps with an additionally alpha channel).
Note that many wxBitmap functions take a type parameter, which is a
value of the ?wxBitmapType enumeration. The validity of those values
depends however on the platform where your program is running and from
the wxWidgets configuration. If all possible wxWidgets settings are
used:
In addition, wxBitmap can load and save all formats that wxImage can;
see wxImage for more info. Of course, you must have loaded the wxImage
handlers (see ?wxInitAllImageHandlers() and wxImage::AddHandler (not
implemented in wx)). Note that all available wxBitmapHandlers for a
given wxWidgets port are automatically loaded at startup so you won't
need to use wxBitmap::AddHandler (not implemented in wx).
More on the difference between wxImage and wxBitmap: wxImage is just a
buffer of RGB bytes with an optional buffer for the alpha bytes. It is
all generic, platform independent and image file format independent
code. It includes generic code for scaling, resizing, clipping, and
other manipulations of the image data. OTOH, wxBitmap is intended to be
a wrapper of whatever is the native image format that is quickest/easi-
est to draw to a DC or to be the target of the drawing operations per-
formed on a wxMemoryDC. By splitting the responsibilities between wxIm-
age/wxBitmap like this then it's easier to use generic code shared by
all platforms and image types for generic operations and platform spe-
cific code where performance or compatibility is needed.
Predefined objects (include wx.hrl): ?wxNullBitmap
See: Overview bitmap, Overview bitmap, wxDC:blit/6, wxIcon, wxCursor,
wxMemoryDC, wxImage, wxPixelData (not implemented in wx)
wxWidgets docs: wxBitmap
DATA TYPES
wxBitmap() = wx:wx_object()
EXPORTS
new() -> wxBitmap()
Default constructor.
Constructs a bitmap object with no data; an assignment or
another member function such as create/4 or loadFile/3 must be
called subsequently.
new(Name) -> wxBitmap()
new(Sz) -> wxBitmap()
new(Img) -> wxBitmap()
Types:
Img = wxImage:wxImage() | wxBitmap:wxBitmap()
new(Width, Height) -> wxBitmap()
new(Name, Height :: [Option]) -> wxBitmap()
new(Sz, Height :: [Option]) -> wxBitmap()
new(Img, Height :: [Option]) -> wxBitmap()
Types:
Img = wxImage:wxImage()
Option = {depth, integer()}
Creates this bitmap object from the given image.
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 provided colour depth (or that
of the current system if depth is ?wxBITMAP_SCREEN_DEPTH) which
entails that a colour reduction may take place.
On Windows, if there is a palette present (set with SetPalette),
it will be used when creating the wxBitmap (most useful in 8-bit
display mode). On other platforms, the palette is currently
ignored.
new(Bits, Width, Height) -> wxBitmap()
new(Width, Height, Height :: [Option]) -> wxBitmap()
Types:
Width = Height = integer()
Option = {depth, integer()}
Creates a new bitmap.
A depth of ?wxBITMAP_SCREEN_DEPTH indicates the depth of the
current screen or visual.
Some platforms only support 1 for monochrome and
?wxBITMAP_SCREEN_DEPTH for the current colour setting.
A depth of 32 including an alpha channel is supported under MSW,
Mac and GTK+.
new(Bits, Width, Height, Options :: [Option]) -> wxBitmap()
Types:
Bits = binary()
Width = Height = integer()
Option = {depth, integer()}
Creates a bitmap from the given array bits.
You should only use this function for monochrome bitmaps (depth
1) in portable programs: in this case the bits parameter should
contain an XBM image.
For other bit depths, the behaviour is platform dependent: under
Windows, the data is passed without any changes to the underly-
ing CreateBitmap() API. Under other platforms, only monochrome
bitmaps may be created using this constructor and wxImage should
be used for creating colour bitmaps from static data.
destroy(This :: wxBitmap()) -> ok
Creates bitmap corresponding to the given cursor.
This can be useful to display a cursor as it cannot be drawn
directly on a window.
This constructor only exists in wxMSW and wxGTK (where it is
implemented for GTK+ 2.8 or later) only.
Since: 3.1.0 Destructor. See overview_refcount_destruct for more
info.
If the application omits to delete the bitmap explicitly, the
bitmap will be destroyed automatically by wxWidgets when the
application exits.
Warning: Do not delete a bitmap that is selected into a memory
device context.
convertToImage(This) -> wxImage:wxImage()
Types:
This = wxBitmap()
Creates 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.
copyFromIcon(This, Icon) -> boolean()
Types:
This = wxBitmap()
Icon = wxIcon:wxIcon()
Creates the bitmap from an icon.
create(This, Sz) -> boolean()
Types:
This = wxBitmap()
Sz = {W :: integer(), H :: integer()}
create(This, Width, Height) -> boolean()
create(This, Sz, Height :: [Option]) -> boolean()
Types:
This = wxBitmap()
Sz = {W :: integer(), H :: integer()}
Option = {depth, integer()}
This is an overloaded member function, provided for convenience.
It differs from the above function only in what argument(s) it
accepts.
create(This, Width, Height, Options :: [Option]) -> boolean()
create(This, Width, Height, Dc) -> boolean()
Types:
This = wxBitmap()
Width = Height = integer()
Dc = wxDC:wxDC()
Create a bitmap compatible with the given DC, inheriting its
magnification factor.
Return: true if the creation was successful.
Since: 3.1.0
getDepth(This) -> integer()
Types:
This = wxBitmap()
Gets the colour depth of the bitmap.
A value of 1 indicates a monochrome bitmap.
getHeight(This) -> integer()
Types:
This = wxBitmap()
Gets the height of the bitmap in pixels.
See: getWidth/1, GetSize() (not implemented in wx)
getPalette(This) -> wxPalette:wxPalette()
Types:
This = wxBitmap()
Gets the associated palette (if any) which may have been loaded
from a file or set for the bitmap.
See: wxPalette
getMask(This) -> wxMask:wxMask()
Types:
This = wxBitmap()
Gets the associated mask (if any) which may have been loaded
from a file or set for the bitmap.
See: setMask/2, wxMask
getWidth(This) -> integer()
Types:
This = wxBitmap()
Gets the width of the bitmap in pixels.
See: getHeight/1, GetSize() (not implemented in wx)
getSubBitmap(This, Rect) -> wxBitmap()
Types:
This = wxBitmap()
Rect =
{X :: integer(),
Y :: integer(),
W :: integer(),
H :: integer()}
Returns a sub bitmap of the current one as long as the rect
belongs entirely to the bitmap.
This function preserves bit depth and mask information.
loadFile(This, Name) -> boolean()
Types:
This = wxBitmap()
Name = unicode:chardata()
loadFile(This, Name, Options :: [Option]) -> boolean()
Types:
This = wxBitmap()
Name = unicode:chardata()
Option = {type, wx:wx_enum()}
Loads a bitmap from a file or resource.
Return: true if the operation succeeded, false otherwise.
Remark: A palette may be associated with the bitmap if one
exists (especially for colour Windows bitmaps), and if the code
supports it. You can check if one has been created by using the
getPalette/1 member.
See: saveFile/4
ok(This) -> boolean()
Types:
This = wxBitmap()
See: isOk/1.
isOk(This) -> boolean()
Types:
This = wxBitmap()
Returns true if bitmap data is present.
saveFile(This, Name, Type) -> boolean()
Types:
This = wxBitmap()
Name = unicode:chardata()
Type = wx:wx_enum()
saveFile(This, Name, Type, Options :: [Option]) -> boolean()
Types:
This = wxBitmap()
Name = unicode:chardata()
Type = wx:wx_enum()
Option = {palette, wxPalette:wxPalette()}
Saves a bitmap in the named file.
Return: true if the operation succeeded, false otherwise.
Remark: Depending on how wxWidgets has been configured, not all
formats may be available.
See: loadFile/3
setDepth(This, Depth) -> ok
Types:
This = wxBitmap()
Depth = integer()
Deprecated: This function is deprecated since version 3.1.2,
dimensions and depth can only be set at construction time.
Sets the depth member (does not affect the bitmap data).
setHeight(This, Height) -> ok
Types:
This = wxBitmap()
Height = integer()
Deprecated: This function is deprecated since version 3.1.2,
dimensions and depth can only be set at construction time.
Sets the height member (does not affect the bitmap data).
setMask(This, Mask) -> ok
Types:
This = wxBitmap()
Mask = wxMask:wxMask()
Sets the mask for this bitmap.
Remark: The bitmap object owns the mask once this has been
called.
Note: A mask can be set also for bitmap with an alpha channel
but doing so under wxMSW is not recommended because performance
of drawing such bitmap is not very good.
See: getMask/1, wxMask
setPalette(This, Palette) -> ok
Types:
This = wxBitmap()
Palette = wxPalette:wxPalette()
Sets the associated palette.
(Not implemented under GTK+).
See: wxPalette
setWidth(This, Width) -> ok
Types:
This = wxBitmap()
Width = integer()
Deprecated: This function is deprecated since version 3.1.2,
dimensions and depth can only be set at construction time.
Sets the width member (does not affect the bitmap data).
wxWidgets team. wx 2.1.1 wxBitmap(3)