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1 ///////////////////////////////////////////////////////////////////////////////
2 // Name: wx/rawbmp.h
3 // Purpose: macros for fast, raw bitmap data access
4 // Author: Eric Kidd, Vadim Zeitlin
5 // Modified by:
6 // Created: 10.03.03
7 // RCS-ID: $Id$
8 // Copyright: (c) 2002 Vadim Zeitlin <vadim@wxwidgets.org>
9 // Licence: wxWindows licence
10 ///////////////////////////////////////////////////////////////////////////////
11
12 #ifndef _WX_RAWBMP_H_
13 #define _WX_RAWBMP_H_
14
15 #include "wx/defs.h"
16
17 #ifdef wxHAS_RAW_BITMAP
18
19 #include "wx/image.h"
20 #include "wx/bitmap.h"
21
22 // ----------------------------------------------------------------------------
23 // Abstract Pixel API
24 //
25 // We need to access our raw bitmap data (1) portably and (2) efficiently.
26 // We do this using a two-dimensional "iteration" interface. Performance
27 // is extremely important here: these functions will be called hundreds
28 // of thousands of times in a row, and even small inefficiencies will
29 // make applications seem slow.
30 //
31 // We can't always rely on inline functions, because not all compilers actually
32 // bother to inline them unless we crank the optimization levels way up.
33 // Therefore, we also provide macros to wring maximum speed out of compiler
34 // unconditionally (e.g. even in debug builds). Of course, if the performance
35 // isn't absolutely crucial for you you shouldn't be using them but the inline
36 // functions instead.
37 // ----------------------------------------------------------------------------
38
39 /*
40 Usage example:
41
42 typedef wxPixelData<wxBitmap, wxNativePixelFormat> PixelData;
43
44 wxBitmap bmp;
45 PixelData data(bmp);
46 if ( !data )
47 {
48 ... raw access to bitmap data unavailable, do something else ...
49 return;
50 }
51
52 if ( data.GetWidth() < 20 || data.GetHeight() < 20 )
53 {
54 ... complain: the bitmap it too small ...
55 return;
56 }
57
58 PixelData::Iterator p(data);
59
60 // we draw a (10, 10)-(20, 20) rect manually using the given r, g, b
61 p.Offset(data, 10, 10);
62
63 for ( int y = 0; y < 10; ++y )
64 {
65 PixelData::Iterator rowStart = p;
66
67 for ( int x = 0; x < 10; ++x, ++p )
68 {
69 p.Red() = r;
70 p.Green() = g;
71 p.Blue() = b;
72 }
73
74 p = rowStart;
75 p.OffsetY(data, 1);
76 }
77 */
78
79 /*
80 Note: we do not use WXDLLIMPEXP_CORE with classes in this file because VC++ has
81 problems with exporting inner class defined inside a specialization of a
82 template class from a DLL. Besides, as all the methods are inline it's not
83 really necessary to put them in DLL at all.
84 */
85
86 // ----------------------------------------------------------------------------
87 // wxPixelFormat
88 // ----------------------------------------------------------------------------
89
90 /*
91 wxPixelFormat is a template class describing the bitmap data format. It
92 contains the constants describing the format of pixel data, but does not
93 describe how the entire bitmap is stored (i.e. top-to-bottom,
94 bottom-to-top, ...). It is also a "traits"-like class, i.e. it only
95 contains some constants and maybe static methods but nothing more, so it
96 can be safely used without incurring any overhead as all accesses to it are
97 done at compile-time.
98
99 Current limitations: we don't support RAGABA and ARAGAB formats supported
100 by Mac OS X. If there is sufficient interest, these classes could be
101 extended to deal with them. Neither do we support alpha channel having
102 different representation from the RGB ones (happens under QNX/Photon I
103 think), but again this could be achieved with some small extra effort.
104
105 Template parameters are:
106 - type of a single pixel component
107 - size of the single pixel in bits
108 - indices of red, green and blue pixel components inside the pixel
109 - index of the alpha component or -1 if none
110 - type which can contain the full pixel value (all channels)
111 */
112
113 template <class Channel,
114 size_t Bpp, int R, int G, int B, int A = -1,
115 class Pixel = wxUint32>
116
117 struct wxPixelFormat
118 {
119 // iterator over pixels is usually of type "ChannelType *"
120 typedef Channel ChannelType;
121
122 // the type which may hold the entire pixel value
123 typedef Pixel PixelType;
124
125 // NB: using static ints initialized inside the class declaration is not
126 // portable as it doesn't work with VC++ 6, so we must use enums
127
128 // size of one pixel in bits
129 enum { BitsPerPixel = Bpp };
130
131 // size of one pixel in ChannelType units (usually bytes)
132 enum { SizePixel = Bpp / (8 * sizeof(Channel)) };
133
134 // the channels indices inside the pixel
135 enum
136 {
137 RED = R,
138 GREEN = G,
139 BLUE = B,
140 ALPHA = A
141 };
142
143 // true if we have an alpha channel (together with the other channels, this
144 // doesn't cover the case of wxImage which stores alpha separately)
145 enum { HasAlpha = A != -1 };
146 };
147
148 // some "predefined" pixel formats
149 // -------------------------------
150
151 // wxImage format is common to all platforms
152 typedef wxPixelFormat<unsigned char, 24, 0, 1, 2> wxImagePixelFormat;
153
154 // the (most common) native bitmap format without alpha support
155 #if defined(__WXMSW__)
156 // under MSW the RGB components are reversed, they're in BGR order
157 typedef wxPixelFormat<unsigned char, 24, 2, 1, 0> wxNativePixelFormat;
158
159 #define wxPIXEL_FORMAT_ALPHA 3
160 #elif defined(__WXMAC__)
161 // under Mac, first component is unused but still present, hence we use
162 // 32bpp, not 24
163 typedef wxPixelFormat<unsigned char, 32, 1, 2, 3> wxNativePixelFormat;
164
165 #define wxPIXEL_FORMAT_ALPHA 0
166 #elif defined(__WXCOCOA__)
167 // Cocoa is standard RGB or RGBA (normally it is RGBA)
168 typedef wxPixelFormat<unsigned char, 24, 0, 1, 2> wxNativePixelFormat;
169
170 #define wxPIXEL_FORMAT_ALPHA 3
171 #elif defined(__WXGTK__)
172 // Under GTK+ 2.X we use GdkPixbuf, which is standard RGB or RGBA
173 typedef wxPixelFormat<unsigned char, 24, 0, 1, 2> wxNativePixelFormat;
174
175 #define wxPIXEL_FORMAT_ALPHA 3
176 #elif defined(__WXDFB__)
177 // Under DirectFB, RGB components are reversed, they're in BGR order
178 typedef wxPixelFormat<unsigned char, 24, 2, 1, 0> wxNativePixelFormat;
179
180 #define wxPIXEL_FORMAT_ALPHA 3
181 #endif
182
183 // the (most common) native format for bitmaps with alpha channel
184 #ifdef wxPIXEL_FORMAT_ALPHA
185 typedef wxPixelFormat<unsigned char, 32,
186 wxNativePixelFormat::RED,
187 wxNativePixelFormat::GREEN,
188 wxNativePixelFormat::BLUE,
189 wxPIXEL_FORMAT_ALPHA> wxAlphaPixelFormat;
190 #endif // wxPIXEL_FORMAT_ALPHA
191
192 // we also define the (default/best) pixel format for the given class: this is
193 // used as default value for the pixel format in wxPixelIterator template
194 template <class T> struct wxPixelFormatFor;
195
196 #if wxUSE_IMAGE
197 // wxPixelFormatFor is only defined for wxImage, attempt to use it with other
198 // classes (wxBitmap...) will result in compile errors which is exactly what we
199 // want
200 template <>
201 struct wxPixelFormatFor<wxImage>
202 {
203 typedef wxImagePixelFormat Format;
204 };
205 #endif //wxUSE_IMAGE
206
207 // ----------------------------------------------------------------------------
208 // wxPixelData
209 // ----------------------------------------------------------------------------
210
211 /*
212 wxPixelDataBase is just a helper for wxPixelData: it contains things common
213 to both wxImage and wxBitmap specializations.
214 */
215 class wxPixelDataBase
216 {
217 public:
218 // origin of the rectangular region we represent
219 wxPoint GetOrigin() const { return m_ptOrigin; }
220
221 // width and height of the region we represent
222 int GetWidth() const { return m_width; }
223 int GetHeight() const { return m_height; }
224
225 wxSize GetSize() const { return wxSize(m_width, m_height); }
226
227 // the distance between two rows
228 int GetRowStride() const { return m_stride; }
229
230 // private: -- see comment in the beginning of the file
231
232 // the origin of this image inside the bigger bitmap (usually (0, 0))
233 wxPoint m_ptOrigin;
234
235 // the size of the image we address, in pixels
236 int m_width,
237 m_height;
238
239 // this parameter is the offset of the start of the (N+1)st row from the
240 // Nth one and can be different from m_bypp*width in some cases:
241 // a) the most usual one is to force 32/64 bit alignment of rows
242 // b) another one is for bottom-to-top images where it's negative
243 // c) finally, it could conceivably be 0 for the images with all
244 // lines being identical
245 int m_stride;
246
247 protected:
248 // ctor is protected because this class is only meant to be used as the
249 // base class by wxPixelData
250 wxPixelDataBase()
251 {
252 m_width =
253 m_height =
254 m_stride = 0;
255 }
256 };
257
258 /*
259 wxPixelData represents the entire bitmap data, i.e. unlike
260 wxPixelFormat (which it uses) it also stores the global bitmap
261 characteristics such as its size, inter-row separation and so on.
262
263 Because of this it can be used to move the pixel iterators (which don't
264 have enough information about the bitmap themselves). This may seem a bit
265 unnatural but must be done in this way to keep the iterator objects as
266 small as possible for maximum efficiency as otherwise they wouldn't be put
267 into the CPU registers by the compiler any more.
268
269 Implementation note: we use the standard workaround for lack of partial
270 template specialization support in VC (both 6 and 7): instead of partly
271 specializing the class Foo<T, U> for some T we introduce FooOut<T> and
272 FooIn<U> nested in it, make Foo<T, U> equivalent to FooOut<T>::FooIn<U> and
273 fully specialize FooOut.
274
275 Also note that this class doesn't have any default definition because we
276 can't really do anything without knowing the exact image class. We do
277 provide wxPixelDataBase to make it simpler to write new wxPixelData
278 specializations.
279 */
280
281 // we need to define this skeleton template to mollify VC++
282 template <class Image>
283 struct wxPixelDataOut
284 {
285 template <class PixelFormat>
286 class wxPixelDataIn
287 {
288 public:
289 class Iterator { };
290 };
291 };
292
293 #if wxUSE_IMAGE
294 // wxPixelData specialization for wxImage: this is the simplest case as we
295 // don't have to care about different pixel formats here
296 template <>
297 struct wxPixelDataOut<wxImage>
298 {
299 // NB: this is a template class even though it doesn't use its template
300 // parameter because otherwise wxPixelData couldn't compile
301 template <class dummyPixelFormat>
302 class wxPixelDataIn : public wxPixelDataBase
303 {
304 public:
305 // the type of the class we're working with
306 typedef wxImage ImageType;
307
308 // the iterator which should be used for working with data in this
309 // format
310 class Iterator
311 {
312 public:
313 // the pixel format we use
314 typedef wxImagePixelFormat PixelFormat;
315
316 // the pixel data we're working with
317 typedef
318 wxPixelDataOut<wxImage>::wxPixelDataIn<PixelFormat> PixelData;
319
320 // go back to (0, 0)
321 void Reset(const PixelData& data)
322 {
323 *this = data.GetPixels();
324 }
325
326 // creates the iterator pointing to the beginning of data
327 Iterator(PixelData& data)
328 {
329 Reset(data);
330 }
331
332 // creates the iterator initially pointing to the image origin
333 Iterator(const wxImage& image)
334 {
335 m_pRGB = image.GetData();
336
337 if ( image.HasAlpha() )
338 {
339 m_pAlpha = image.GetAlpha();
340 }
341 else // alpha is not used at all
342 {
343 m_pAlpha = NULL;
344 }
345 }
346
347 // true if the iterator is valid
348 bool IsOk() const { return m_pRGB != NULL; }
349
350
351 // navigation
352 // ----------
353
354 // advance the iterator to the next pixel, prefix version
355 Iterator& operator++()
356 {
357 m_pRGB += PixelFormat::SizePixel;
358 if ( m_pAlpha )
359 ++m_pAlpha;
360
361 return *this;
362 }
363
364 // postfix (hence less efficient -- don't use it unless you
365 // absolutely must) version
366 Iterator operator++(int)
367 {
368 Iterator p(*this);
369 ++*this;
370 return p;
371 }
372
373 // move x pixels to the right and y down
374 //
375 // note that the rows don't wrap!
376 void Offset(const PixelData& data, int x, int y)
377 {
378 m_pRGB += data.GetRowStride()*y + PixelFormat::SizePixel*x;
379 if ( m_pAlpha )
380 m_pAlpha += data.GetWidth() + x;
381 }
382
383 // move x pixels to the right (again, no row wrapping)
384 void OffsetX(const PixelData& WXUNUSED(data), int x)
385 {
386 m_pRGB += PixelFormat::SizePixel*x;
387 if ( m_pAlpha )
388 m_pAlpha += x;
389 }
390
391 // move y rows to the bottom
392 void OffsetY(const PixelData& data, int y)
393 {
394 m_pRGB += data.GetRowStride()*y;
395 if ( m_pAlpha )
396 m_pAlpha += data.GetWidth();
397 }
398
399 // go to the given position
400 void MoveTo(const PixelData& data, int x, int y)
401 {
402 Reset(data);
403 Offset(data, x, y);
404 }
405
406
407 // data access
408 // -----------
409
410 // access to individual colour components
411 PixelFormat::ChannelType& Red() { return m_pRGB[PixelFormat::RED]; }
412 PixelFormat::ChannelType& Green() { return m_pRGB[PixelFormat::GREEN]; }
413 PixelFormat::ChannelType& Blue() { return m_pRGB[PixelFormat::BLUE]; }
414 PixelFormat::ChannelType& Alpha() { return *m_pAlpha; }
415
416 // address the pixel contents directly (always RGB, without alpha)
417 //
418 // this can't be used to modify the image as assigning a 32bpp
419 // value to 24bpp pixel would overwrite an extra byte in the next
420 // pixel or beyond the end of image
421 const typename PixelFormat::PixelType& Data()
422 { return *(typename PixelFormat::PixelType *)m_pRGB; }
423
424 // private: -- see comment in the beginning of the file
425
426 // pointer into RGB buffer
427 unsigned char *m_pRGB;
428
429 // pointer into alpha buffer or NULL if alpha isn't used
430 unsigned char *m_pAlpha;
431 };
432
433 // initializes us with the data of the given image
434 wxPixelDataIn(ImageType& image) : m_image(image), m_pixels(image)
435 {
436 m_width = image.GetWidth();
437 m_height = image.GetHeight();
438 m_stride = Iterator::PixelFormat::SizePixel * m_width;
439 }
440
441 // initializes us with the given region of the specified image
442 wxPixelDataIn(ImageType& image,
443 const wxPoint& pt,
444 const wxSize& sz) : m_image(image), m_pixels(image)
445 {
446 m_stride = Iterator::PixelFormat::SizePixel * m_width;
447
448 InitRect(pt, sz);
449 }
450
451 // initializes us with the given region of the specified image
452 wxPixelDataIn(ImageType& image,
453 const wxRect& rect) : m_image(image), m_pixels(image)
454 {
455 m_stride = Iterator::PixelFormat::SizePixel * m_width;
456
457 InitRect(rect.GetPosition(), rect.GetSize());
458 }
459
460 // we evaluate to true only if we could get access to bitmap data
461 // successfully
462 operator bool() const { return m_pixels.IsOk(); }
463
464 // get the iterator pointing to the origin
465 Iterator GetPixels() const { return m_pixels; }
466
467 private:
468 void InitRect(const wxPoint& pt, const wxSize& sz)
469 {
470 m_width = sz.x;
471 m_height = sz.y;
472
473 m_ptOrigin = pt;
474 m_pixels.Offset(*this, pt.x, pt.y);
475 }
476
477 // the image we're working with
478 ImageType& m_image;
479
480 // the iterator pointing to the image origin
481 Iterator m_pixels;
482 };
483 };
484 #endif //wxUSE_IMAGE
485
486 #if wxUSE_GUI
487 // wxPixelData specialization for wxBitmap: here things are more interesting as
488 // we also have to support different pixel formats
489 template <>
490 struct wxPixelDataOut<wxBitmap>
491 {
492 template <class Format>
493 class wxPixelDataIn : public wxPixelDataBase
494 {
495 public:
496 // the type of the class we're working with
497 typedef wxBitmap ImageType;
498
499 class Iterator
500 {
501 public:
502 // the pixel format we use
503 typedef Format PixelFormat;
504
505 // the type of the pixel components
506 typedef typename PixelFormat::ChannelType ChannelType;
507
508 // the pixel data we're working with
509 typedef wxPixelDataOut<wxBitmap>::wxPixelDataIn<Format> PixelData;
510
511
512 // go back to (0, 0)
513 void Reset(const PixelData& data)
514 {
515 *this = data.GetPixels();
516 }
517
518 // initializes the iterator to point to the origin of the given
519 // pixel data
520 Iterator(PixelData& data)
521 {
522 Reset(data);
523 }
524
525 // initializes the iterator to point to the origin of the given
526 // bitmap
527 Iterator(wxBitmap& bmp, PixelData& data)
528 {
529 // using cast here is ugly but it should be safe as
530 // GetRawData() real return type should be consistent with
531 // BitsPerPixel (which is in turn defined by ChannelType) and
532 // this is the only thing we can do without making GetRawData()
533 // a template function which is undesirable
534 m_ptr = (ChannelType *)
535 bmp.GetRawData(data, PixelFormat::BitsPerPixel);
536 }
537
538 // default constructor
539 Iterator()
540 {
541 m_ptr = NULL;
542 }
543
544 // return true if this iterator is valid
545 bool IsOk() const { return m_ptr != NULL; }
546
547
548 // navigation
549 // ----------
550
551 // advance the iterator to the next pixel, prefix version
552 Iterator& operator++()
553 {
554 m_ptr += PixelFormat::SizePixel;
555
556 return *this;
557 }
558
559 // postfix (hence less efficient -- don't use it unless you
560 // absolutely must) version
561 Iterator operator++(int)
562 {
563 Iterator p(*this);
564 ++*this;
565 return p;
566 }
567
568 // move x pixels to the right and y down
569 //
570 // note that the rows don't wrap!
571 void Offset(const PixelData& data, int x, int y)
572 {
573 m_ptr += data.GetRowStride()*y + PixelFormat::SizePixel*x;
574 }
575
576 // move x pixels to the right (again, no row wrapping)
577 void OffsetX(const PixelData& WXUNUSED(data), int x)
578 {
579 m_ptr += PixelFormat::SizePixel*x;
580 }
581
582 // move y rows to the bottom
583 void OffsetY(const PixelData& data, int y)
584 {
585 m_ptr += data.GetRowStride()*y;
586 }
587
588 // go to the given position
589 void MoveTo(const PixelData& data, int x, int y)
590 {
591 Reset(data);
592 Offset(data, x, y);
593 }
594
595
596 // data access
597 // -----------
598
599 // access to individual colour components
600 ChannelType& Red() { return m_ptr[PixelFormat::RED]; }
601 ChannelType& Green() { return m_ptr[PixelFormat::GREEN]; }
602 ChannelType& Blue() { return m_ptr[PixelFormat::BLUE]; }
603 ChannelType& Alpha() { return m_ptr[PixelFormat::ALPHA]; }
604
605 // address the pixel contents directly
606 //
607 // warning: the format is platform dependent
608 //
609 // warning 2: assigning to Data() only works correctly for 16bpp or
610 // 32bpp formats but using it for 24bpp ones overwrites
611 // one extra byte and so can't be done
612 typename PixelFormat::PixelType& Data()
613 { return *(typename PixelFormat::PixelType *)m_ptr; }
614
615 // private: -- see comment in the beginning of the file
616
617 // for efficiency reasons this class should not have any other
618 // fields, otherwise it won't be put into a CPU register (as it
619 // should inside the inner loops) by some compilers, notably gcc
620 ChannelType *m_ptr;
621 };
622
623 // ctor associates this pointer with a bitmap and locks the bitmap for
624 // raw access, it will be unlocked only by our dtor and so these
625 // objects should normally be only created on the stack, i.e. have
626 // limited life-time
627 wxPixelDataIn(wxBitmap& bmp) : m_bmp(bmp), m_pixels(bmp, *this)
628 {
629 }
630
631 wxPixelDataIn(wxBitmap& bmp, const wxRect& rect)
632 : m_bmp(bmp), m_pixels(bmp, *this)
633 {
634 InitRect(rect.GetPosition(), rect.GetSize());
635 }
636
637 wxPixelDataIn(wxBitmap& bmp, const wxPoint& pt, const wxSize& sz)
638 : m_bmp(bmp), m_pixels(bmp, *this)
639 {
640 InitRect(pt, sz);
641 }
642
643 // we evaluate to true only if we could get access to bitmap data
644 // successfully
645 operator bool() const { return m_pixels.IsOk(); }
646
647 // get the iterator pointing to the origin
648 Iterator GetPixels() const { return m_pixels; }
649
650 // dtor unlocks the bitmap
651 ~wxPixelDataIn()
652 {
653 if ( m_pixels.IsOk() )
654 {
655 #if defined(__WXMSW__) || defined(__WXMAC__)
656 // this is a hack to mark wxBitmap as using alpha channel
657 if ( Format::HasAlpha )
658 m_bmp.UseAlpha();
659 #endif
660 m_bmp.UngetRawData(*this);
661 }
662 // else: don't call UngetRawData() if GetRawData() failed
663 }
664
665 #if WXWIN_COMPATIBILITY_2_8
666 // not needed anymore, calls to it should be simply removed
667 wxDEPRECATED_INLINE( void UseAlpha(), wxEMPTY_PARAMETER_VALUE )
668 #endif
669
670 // private: -- see comment in the beginning of the file
671
672 // the bitmap we're associated with
673 wxBitmap m_bmp;
674
675 // the iterator pointing to the image origin
676 Iterator m_pixels;
677
678 private:
679 void InitRect(const wxPoint& pt, const wxSize& sz)
680 {
681 m_pixels.Offset(*this, pt.x, pt.y);
682
683 m_ptOrigin = pt;
684 m_width = sz.x;
685 m_height = sz.y;
686 }
687 };
688 };
689
690 #endif //wxUSE_GUI
691
692 // FIXME-VC6: VC6 doesn't like typename in default template parameters while
693 // it is necessary with standard-conforming compilers, remove this
694 // #define and just use typename when we drop VC6 support
695 #if defined(__VISUALC__) && !wxCHECK_VISUALC_VERSION(7)
696 #define wxTYPENAME_IN_TEMPLATE_DEFAULT_PARAM
697 #else
698 #define wxTYPENAME_IN_TEMPLATE_DEFAULT_PARAM typename
699 #endif
700
701 template <class Image,
702 class PixelFormat = wxTYPENAME_IN_TEMPLATE_DEFAULT_PARAM
703 wxPixelFormatFor<Image>::Format >
704 class wxPixelData :
705 public wxPixelDataOut<Image>::template wxPixelDataIn<PixelFormat>
706 {
707 public:
708 typedef
709 typename wxPixelDataOut<Image>::template wxPixelDataIn<PixelFormat>
710 Base;
711
712 wxPixelData(Image& image) : Base(image) { }
713
714 wxPixelData(Image& i, const wxRect& rect) : Base(i, rect) { }
715
716 wxPixelData(Image& i, const wxPoint& pt, const wxSize& sz)
717 : Base(i, pt, sz)
718 {
719 }
720 };
721
722 // some "predefined" pixel data classes
723 #if wxUSE_IMAGE
724 typedef wxPixelData<wxImage> wxImagePixelData;
725 #endif //wxUSE_IMAGE
726 #if wxUSE_GUI
727 typedef wxPixelData<wxBitmap, wxNativePixelFormat> wxNativePixelData;
728 typedef wxPixelData<wxBitmap, wxAlphaPixelFormat> wxAlphaPixelData;
729
730 #endif //wxUSE_GUI
731
732 // ----------------------------------------------------------------------------
733 // wxPixelIterator
734 // ----------------------------------------------------------------------------
735
736 /*
737 wxPixel::Iterator represents something which points to the pixel data and
738 allows us to iterate over it. In the simplest case of wxBitmap it is,
739 indeed, just a pointer, but it can be something more complicated and,
740 moreover, you are free to specialize it for other image classes and bitmap
741 formats.
742
743 Note that although it would have been much more intuitive to have a real
744 class here instead of what we have now, this class would need two template
745 parameters, and this can't be done because we'd need compiler support for
746 partial template specialization then and neither VC6 nor VC7 provide it.
747 */
748 template < class Image, class PixelFormat = wxPixelFormatFor<Image> >
749 struct wxPixelIterator : public wxPixelData<Image, PixelFormat>::Iterator
750 {
751 };
752
753 #endif // wxHAS_RAW_BITMAP
754 #endif // _WX_RAWBMP_H_