wxWidgets/include/wx/msw/dib.h
Kolya Kosenko da195023c1 Fix wxGTK/MSW build in wxDIB.
Don't define wxMSW-specific wxDIB::CreatePalette() method when not building
wxMSW.

Closes #17248.
2016-03-09 15:42:51 +01:00

279 lines
8.5 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: wx/msw/dib.h
// Purpose: wxDIB class representing Win32 device independent bitmaps
// Author: Vadim Zeitlin
// Modified by:
// Created: 03.03.03 (replaces the old file with the same name)
// Copyright: (c) 1997-2003 wxWidgets team
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_MSW_DIB_H_
#define _WX_MSW_DIB_H_
class WXDLLIMPEXP_FWD_CORE wxPalette;
#include "wx/msw/private.h"
#if wxUSE_WXDIB
#ifdef __WXMSW__
#include "wx/bitmap.h"
#endif // __WXMSW__
// ----------------------------------------------------------------------------
// wxDIB: represents a DIB section
// ----------------------------------------------------------------------------
class WXDLLIMPEXP_CORE wxDIB
{
public:
// ctors and such
// --------------
// create an uninitialized DIB with the given width, height and depth (only
// 24 and 32 bpp DIBs are currently supported)
//
// after using this ctor, GetData() and GetHandle() may be used if IsOk()
// returns true
wxDIB(int width, int height, int depth)
{ Init(); (void)Create(width, height, depth); }
#ifdef __WXMSW__
// create a DIB from the DDB
wxDIB(const wxBitmap& bmp)
{ Init(); (void)Create(bmp); }
#endif // __WXMSW__
// create a DIB from the Windows DDB
wxDIB(HBITMAP hbmp)
{ Init(); (void)Create(hbmp); }
// load a DIB from file (any depth is supoprted here unlike above)
//
// as above, use IsOk() to see if the bitmap was loaded successfully
wxDIB(const wxString& filename)
{ Init(); (void)Load(filename); }
// same as the corresponding ctors but with return value
bool Create(int width, int height, int depth);
#ifdef __WXMSW__
bool Create(const wxBitmap& bmp) { return Create(GetHbitmapOf(bmp)); }
#endif
bool Create(HBITMAP hbmp);
bool Load(const wxString& filename);
// dtor is not virtual, this class is not meant to be used polymorphically
~wxDIB();
// operations
// ----------
// create a bitmap compatible with the given HDC (or screen by default) and
// return its handle, the caller is responsible for freeing it (using
// DeleteObject())
HBITMAP CreateDDB(HDC hdc = 0) const;
// get the handle from the DIB and reset it, i.e. this object won't destroy
// the DIB after this (but the caller should do it)
HBITMAP Detach() { HBITMAP hbmp = m_handle; m_handle = 0; return hbmp; }
#if defined(__WXMSW__) && wxUSE_PALETTE
// create a palette for this DIB (always a trivial/default one for 24bpp)
wxPalette *CreatePalette() const;
#endif // defined(__WXMSW__) && wxUSE_PALETTE
// save the DIB as a .BMP file to the file with the given name
bool Save(const wxString& filename);
// accessors
// ---------
// return true if DIB was successfully created, false otherwise
bool IsOk() const { return m_handle != 0; }
// get the bitmap size
wxSize GetSize() const { DoGetObject(); return wxSize(m_width, m_height); }
int GetWidth() const { DoGetObject(); return m_width; }
int GetHeight() const { DoGetObject(); return m_height; }
// get the number of bits per pixel, or depth
int GetDepth() const { DoGetObject(); return m_depth; }
// get the DIB handle
HBITMAP GetHandle() const { return m_handle; }
// get raw pointer to bitmap bits, you should know what you do if you
// decide to use it
unsigned char *GetData() const
{ DoGetObject(); return (unsigned char *)m_data; }
// HBITMAP conversion
// ------------------
// these functions are only used by wxWidgets internally right now, please
// don't use them directly if possible as they're subject to change
// creates a DDB compatible with the given (or screen) DC from either
// a plain DIB or a DIB section (in which case the last parameter must be
// non NULL)
static HBITMAP ConvertToBitmap(const BITMAPINFO *pbi,
HDC hdc = 0,
void *bits = NULL);
// create a plain DIB (not a DIB section) from a DDB, the caller is
// responsable for freeing it using ::GlobalFree()
static HGLOBAL ConvertFromBitmap(HBITMAP hbmp);
// creates a DIB from the given DDB or calculates the space needed by it:
// if pbi is NULL, only the space is calculated, otherwise pbi is supposed
// to point at BITMAPINFO of the correct size which is filled by this
// function (this overload is needed for wxBitmapDataObject code in
// src/msw/ole/dataobj.cpp)
static size_t ConvertFromBitmap(BITMAPINFO *pbi, HBITMAP hbmp);
// wxImage conversion
// ------------------
#if wxUSE_IMAGE
// Possible formats for DIBs created by the functions below.
enum PixelFormat
{
PixelFormat_PreMultiplied = 0,
PixelFormat_NotPreMultiplied = 1
};
// Create a DIB from the given image, the DIB will be either 24 or 32 (if
// the image has alpha channel) bpp.
//
// By default the DIB stores pixel data in pre-multiplied format so that it
// can be used with ::AlphaBlend() but it is also possible to disable
// pre-multiplication for the DIB to be usable with ImageList_Draw() which
// does pre-multiplication internally.
wxDIB(const wxImage& image, PixelFormat pf = PixelFormat_PreMultiplied)
{
Init();
(void)Create(image, pf);
}
// same as the above ctor but with the return code
bool Create(const wxImage& image, PixelFormat pf = PixelFormat_PreMultiplied);
// create wxImage having the same data as this DIB
// Possible options of conversion to wxImage
enum ConversionFlags
{
// Determine whether 32bpp DIB contains real alpha channel
// and return wxImage with or without alpha channel values.
Convert_AlphaAuto,
// Assume that 32bpp DIB contains valid alpha channel and always
// return wxImage with alpha channel values in this case.
Convert_AlphaAlwaysIf32bpp
};
wxImage ConvertToImage(ConversionFlags flags = Convert_AlphaAuto) const;
#endif // wxUSE_IMAGE
// helper functions
// ----------------
// return the size of one line in a DIB with given width and depth: the
// point here is that as the scan lines need to be DWORD aligned so we may
// need to add some padding
static unsigned long GetLineSize(int width, int depth)
{
return ((width*depth + 31) & ~31) >> 3;
}
private:
// common part of all ctors
void Init();
// free resources
void Free();
// initialize the contents from the provided DDB (Create() must have been
// already called)
bool CopyFromDDB(HBITMAP hbmp);
// the DIB section handle, 0 if invalid
HBITMAP m_handle;
// NB: we could store only m_handle and not any of the other fields as
// we may always retrieve them from it using ::GetObject(), but we
// decide to still store them for efficiency concerns -- however if we
// don't have them from the very beginning (e.g. DIB constructed from a
// bitmap), we only retrieve them when necessary and so these fields
// should *never* be accessed directly, even from inside wxDIB code
// function which must be called before accessing any members and which
// gets their values from m_handle, if not done yet
void DoGetObject() const;
// pointer to DIB bits, may be NULL
void *m_data;
// size and depth of the image
int m_width,
m_height,
m_depth;
// in some cases we could be using a handle which we didn't create and in
// this case we shouldn't free it neither -- this flag tell us if this is
// the case
bool m_ownsHandle;
// DIBs can't be copied
wxDIB(const wxDIB&);
wxDIB& operator=(const wxDIB&);
};
// ----------------------------------------------------------------------------
// inline functions implementation
// ----------------------------------------------------------------------------
inline
void wxDIB::Init()
{
m_handle = 0;
m_ownsHandle = true;
m_data = NULL;
m_width =
m_height =
m_depth = 0;
}
inline
void wxDIB::Free()
{
if ( m_handle && m_ownsHandle )
{
if ( !::DeleteObject(m_handle) )
{
wxLogLastError(wxT("DeleteObject(hDIB)"));
}
Init();
}
}
inline wxDIB::~wxDIB()
{
Free();
}
#endif
// wxUSE_WXDIB
#endif // _WX_MSW_DIB_H_