wxWidgets/include/wx/palmos/dib.h
2004-10-19 13:40:30 +00:00

244 lines
7.1 KiB
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/////////////////////////////////////////////////////////////////////////////
// Name: wx/palmos/dib.h
// Purpose: wxDIB class representing device independent bitmaps
// Author: William Osborne
// Modified by:
// Created: 10/13/04
// RCS-ID: $Id:
// Copyright: (c) William Osborne
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_PALMOS_DIB_H_
#define _WX_PALMOS_DIB_H_
class WXDLLEXPORT wxBitmap;
class WXDLLEXPORT wxPalette;
#include "wx/msw/private.h"
#if wxUSE_WXDIB
// ----------------------------------------------------------------------------
// wxDIB: represents a DIB section
// ----------------------------------------------------------------------------
class WXDLLEXPORT 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); }
// create a DIB from the DDB
wxDIB(const wxBitmap& bmp)
{ Init(); (void)Create(bmp); }
// 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);
bool Create(const wxBitmap& bmp);
bool Load(const wxString& filename);
// dtor is not virtual, this class is not meant to be used polymorphically
~wxDIB();
// operations
// ----------
#ifndef __WXWINCE__
// create a bitmap compatiblr 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;
#endif // !__WXWINCE__
// 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 wxUSE_PALETTE
// create a palette for this DIB (always a trivial/default one for 24bpp)
wxPalette *CreatePalette() const;
#endif // 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
void *GetData() const { DoGetObject(); return 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
#ifndef __WXWINCE__
// 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);
#endif // __WXWINCE__
// wxImage conversion
// ------------------
#if wxUSE_IMAGE
// create a DIB from the given image, the DIB will be either 24 or 32 (if
// the image has alpha channel) bpp
wxDIB(const wxImage& image) { Init(); (void)Create(image); }
// same as the above ctor but with the return code
bool Create(const wxImage& image);
// create wxImage having the same data as this DIB
wxImage ConvertToImage() 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_PALMOS_DIB_H_