1 /*
2   Simple DirectMedia Layer
3   Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>
4 
5   This software is provided 'as-is', without any express or implied
6   warranty.  In no event will the authors be held liable for any damages
7   arising from the use of this software.
8 
9   Permission is granted to anyone to use this software for any purpose,
10   including commercial applications, and to alter it and redistribute it
11   freely, subject to the following restrictions:
12 
13   1. The origin of this software must not be misrepresented; you must not
14      claim that you wrote the original software. If you use this software
15      in a product, an acknowledgment in the product documentation would be
16      appreciated but is not required.
17   2. Altered source versions must be plainly marked as such, and must not be
18      misrepresented as being the original software.
19   3. This notice may not be removed or altered from any source distribution.
20 */
21 
22 /**
23  *  \file SDL_surface.h
24  *
25  *  Header file for ::SDL_Surface definition and management functions.
26  */
27 
28 #ifndef SDL_surface_h_
29 #define SDL_surface_h_
30 
31 #include "SDL_stdinc.h"
32 #include "SDL_pixels.h"
33 #include "SDL_rect.h"
34 #include "SDL_blendmode.h"
35 #include "SDL_rwops.h"
36 
37 #include "begin_code.h"
38 /* Set up for C function definitions, even when using C++ */
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42 
43 /**
44  *  \name Surface flags
45  *
46  *  These are the currently supported flags for the ::SDL_Surface.
47  *
48  *  \internal
49  *  Used internally (read-only).
50  */
51 /* @{ */
52 #define SDL_SWSURFACE       0           /**< Just here for compatibility */
53 #define SDL_PREALLOC        0x00000001  /**< Surface uses preallocated memory */
54 #define SDL_RLEACCEL        0x00000002  /**< Surface is RLE encoded */
55 #define SDL_DONTFREE        0x00000004  /**< Surface is referenced internally */
56 #define SDL_SIMD_ALIGNED    0x00000008  /**< Surface uses aligned memory */
57 /* @} *//* Surface flags */
58 
59 /**
60  *  Evaluates to true if the surface needs to be locked before access.
61  */
62 #define SDL_MUSTLOCK(S) (((S)->flags & SDL_RLEACCEL) != 0)
63 
64 /**
65  * \brief A collection of pixels used in software blitting.
66  *
67  * \note  This structure should be treated as read-only, except for \c pixels,
68  *        which, if not NULL, contains the raw pixel data for the surface.
69  */
70 typedef struct SDL_Surface
71 {
72     Uint32 flags;               /**< Read-only */
73     SDL_PixelFormat *format;    /**< Read-only */
74     int w, h;                   /**< Read-only */
75     int pitch;                  /**< Read-only */
76     void *pixels;               /**< Read-write */
77 
78     /** Application data associated with the surface */
79     void *userdata;             /**< Read-write */
80 
81     /** information needed for surfaces requiring locks */
82     int locked;                 /**< Read-only */
83 
84     /** list of BlitMap that hold a reference to this surface */
85     void *list_blitmap;         /**< Private */
86 
87     /** clipping information */
88     SDL_Rect clip_rect;         /**< Read-only */
89 
90     /** info for fast blit mapping to other surfaces */
91     struct SDL_BlitMap *map;    /**< Private */
92 
93     /** Reference count -- used when freeing surface */
94     int refcount;               /**< Read-mostly */
95 } SDL_Surface;
96 
97 /**
98  * \brief The type of function used for surface blitting functions.
99  */
100 typedef int (SDLCALL *SDL_blit) (struct SDL_Surface * src, SDL_Rect * srcrect,
101                                  struct SDL_Surface * dst, SDL_Rect * dstrect);
102 
103 /**
104  * \brief The formula used for converting between YUV and RGB
105  */
106 typedef enum
107 {
108     SDL_YUV_CONVERSION_JPEG,        /**< Full range JPEG */
109     SDL_YUV_CONVERSION_BT601,       /**< BT.601 (the default) */
110     SDL_YUV_CONVERSION_BT709,       /**< BT.709 */
111     SDL_YUV_CONVERSION_AUTOMATIC    /**< BT.601 for SD content, BT.709 for HD content */
112 } SDL_YUV_CONVERSION_MODE;
113 
114 /**
115  * Allocate a new RGB surface.
116  *
117  * If `depth` is 4 or 8 bits, an empty palette is allocated for the surface.
118  * If `depth` is greater than 8 bits, the pixel format is set using the
119  * [RGBA]mask parameters.
120  *
121  * The [RGBA]mask parameters are the bitmasks used to extract that color from
122  * a pixel. For instance, `Rmask` being 0xFF000000 means the red data is
123  * stored in the most significant byte. Using zeros for the RGB masks sets a
124  * default value, based on the depth. For example:
125  *
126  * ```c++
127  * SDL_CreateRGBSurface(0,w,h,32,0,0,0,0);
128  * ```
129  *
130  * However, using zero for the Amask results in an Amask of 0.
131  *
132  * By default surfaces with an alpha mask are set up for blending as with:
133  *
134  * ```c++
135  * SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND)
136  * ```
137  *
138  * You can change this by calling SDL_SetSurfaceBlendMode() and selecting a
139  * different `blendMode`.
140  *
141  * \param flags the flags are unused and should be set to 0
142  * \param width the width of the surface
143  * \param height the height of the surface
144  * \param depth the depth of the surface in bits
145  * \param Rmask the red mask for the pixels
146  * \param Gmask the green mask for the pixels
147  * \param Bmask the blue mask for the pixels
148  * \param Amask the alpha mask for the pixels
149  * \returns the new SDL_Surface structure that is created or NULL if it fails;
150  *          call SDL_GetError() for more information.
151  *
152  * \sa SDL_CreateRGBSurfaceFrom
153  * \sa SDL_CreateRGBSurfaceWithFormat
154  * \sa SDL_FreeSurface
155  */
156 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface
157     (Uint32 flags, int width, int height, int depth,
158      Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
159 
160 
161 /* !!! FIXME for 2.1: why does this ask for depth? Format provides that. */
162 /**
163  * Allocate a new RGB surface with a specific pixel format.
164  *
165  * This function operates mostly like SDL_CreateRGBSurface(), except instead
166  * of providing pixel color masks, you provide it with a predefined format
167  * from SDL_PixelFormatEnum.
168  *
169  * \param flags the flags are unused and should be set to 0
170  * \param width the width of the surface
171  * \param height the height of the surface
172  * \param depth the depth of the surface in bits
173  * \param format the SDL_PixelFormatEnum for the new surface's pixel format.
174  * \returns the new SDL_Surface structure that is created or NULL if it fails;
175  *          call SDL_GetError() for more information.
176  *
177  * \sa SDL_CreateRGBSurface
178  * \sa SDL_CreateRGBSurfaceFrom
179  * \sa SDL_FreeSurface
180  */
181 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormat
182     (Uint32 flags, int width, int height, int depth, Uint32 format);
183 
184 /**
185  * Allocate a new RGB surface with existing pixel data.
186  *
187  * This function operates mostly like SDL_CreateRGBSurface(), except it does
188  * not allocate memory for the pixel data, instead the caller provides an
189  * existing buffer of data for the surface to use.
190  *
191  * No copy is made of the pixel data. Pixel data is not managed automatically;
192  * you must free the surface before you free the pixel data.
193  *
194  * \param pixels a pointer to existing pixel data
195  * \param width the width of the surface
196  * \param height the height of the surface
197  * \param depth the depth of the surface in bits
198  * \param pitch the pitch of the surface in bytes
199  * \param Rmask the red mask for the pixels
200  * \param Gmask the green mask for the pixels
201  * \param Bmask the blue mask for the pixels
202  * \param Amask the alpha mask for the pixels
203  * \returns the new SDL_Surface structure that is created or NULL if it fails;
204  *          call SDL_GetError() for more information.
205  *
206  * \sa SDL_CreateRGBSurface
207  * \sa SDL_CreateRGBSurfaceWithFormat
208  * \sa SDL_FreeSurface
209  */
210 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels,
211                                                               int width,
212                                                               int height,
213                                                               int depth,
214                                                               int pitch,
215                                                               Uint32 Rmask,
216                                                               Uint32 Gmask,
217                                                               Uint32 Bmask,
218                                                               Uint32 Amask);
219 
220 /* !!! FIXME for 2.1: why does this ask for depth? Format provides that. */
221 /**
222  * Allocate a new RGB surface with with a specific pixel format and existing
223  * pixel data.
224  *
225  * This function operates mostly like SDL_CreateRGBSurfaceFrom(), except
226  * instead of providing pixel color masks, you provide it with a predefined
227  * format from SDL_PixelFormatEnum.
228  *
229  * No copy is made of the pixel data. Pixel data is not managed automatically;
230  * you must free the surface before you free the pixel data.
231  *
232  * \param pixels a pointer to existing pixel data
233  * \param width the width of the surface
234  * \param height the height of the surface
235  * \param depth the depth of the surface in bits
236  * \param pitch the pitch of the surface in bytes
237  * \param format the SDL_PixelFormatEnum for the new surface's pixel format.
238  * \returns the new SDL_Surface structure that is created or NULL if it fails;
239  *          call SDL_GetError() for more information.
240  *
241  * \sa SDL_CreateRGBSurfaceFrom
242  * \sa SDL_CreateRGBSurfaceWithFormat
243  * \sa SDL_FreeSurface
244  */
245 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormatFrom
246     (void *pixels, int width, int height, int depth, int pitch, Uint32 format);
247 
248 /**
249  * Free an RGB surface.
250  *
251  * It is safe to pass NULL to this function.
252  *
253  * \param surface the SDL_Surface to free.
254  *
255  * \sa SDL_CreateRGBSurface
256  * \sa SDL_CreateRGBSurfaceFrom
257  * \sa SDL_LoadBMP
258  * \sa SDL_LoadBMP_RW
259  */
260 extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface);
261 
262 /**
263  * Set the palette used by a surface.
264  *
265  * A single palette can be shared with many surfaces.
266  *
267  * \param surface the SDL_Surface structure to update
268  * \param palette the SDL_Palette structure to use
269  * \returns 0 on success or a negative error code on failure; call
270  *          SDL_GetError() for more information.
271  */
272 extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface,
273                                                   SDL_Palette * palette);
274 
275 /**
276  * Set up a surface for directly accessing the pixels.
277  *
278  * Between calls to SDL_LockSurface() / SDL_UnlockSurface(), you can write to
279  * and read from `surface->pixels`, using the pixel format stored in
280  * `surface->format`. Once you are done accessing the surface, you should use
281  * SDL_UnlockSurface() to release it.
282  *
283  * Not all surfaces require locking. If `SDL_MUSTLOCK(surface)` evaluates to
284  * 0, then you can read and write to the surface at any time, and the pixel
285  * format of the surface will not change.
286  *
287  * \param surface the SDL_Surface structure to be locked
288  * \returns 0 on success or a negative error code on failure; call
289  *          SDL_GetError() for more information.
290  *
291  * \sa SDL_MUSTLOCK
292  * \sa SDL_UnlockSurface
293  */
294 extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface);
295 
296 /**
297  * Release a surface after directly accessing the pixels.
298  *
299  * \param surface the SDL_Surface structure to be unlocked
300  *
301  * \sa SDL_LockSurface
302  */
303 extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface);
304 
305 /**
306  * Load a BMP image from a seekable SDL data stream.
307  *
308  * The new surface should be freed with SDL_FreeSurface().
309  *
310  * \param src the data stream for the surface
311  * \param freesrc non-zero to close the stream after being read
312  * \returns a pointer to a new SDL_Surface structure or NULL if there was an
313  *          error; call SDL_GetError() for more information.
314  *
315  * \sa SDL_FreeSurface
316  * \sa SDL_LoadBMP
317  * \sa SDL_SaveBMP_RW
318  */
319 extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src,
320                                                     int freesrc);
321 
322 /**
323  * Load a surface from a file.
324  *
325  * Convenience macro.
326  */
327 #define SDL_LoadBMP(file)   SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1)
328 
329 /**
330  * Save a surface to a seekable SDL data stream in BMP format.
331  *
332  * Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the
333  * BMP directly. Other RGB formats with 8-bit or higher get converted to a
334  * 24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit
335  * surface before they are saved. YUV and paletted 1-bit and 4-bit formats are
336  * not supported.
337  *
338  * \param surface the SDL_Surface structure containing the image to be saved
339  * \param dst a data stream to save to
340  * \param freedst non-zero to close the stream after being written
341  * \returns 0 on success or a negative error code on failure; call
342  *          SDL_GetError() for more information.
343  *
344  * \sa SDL_LoadBMP_RW
345  * \sa SDL_SaveBMP
346  */
347 extern DECLSPEC int SDLCALL SDL_SaveBMP_RW
348     (SDL_Surface * surface, SDL_RWops * dst, int freedst);
349 
350 /**
351  *  Save a surface to a file.
352  *
353  *  Convenience macro.
354  */
355 #define SDL_SaveBMP(surface, file) \
356         SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1)
357 
358 /**
359  * Set the RLE acceleration hint for a surface.
360  *
361  * If RLE is enabled, color key and alpha blending blits are much faster, but
362  * the surface must be locked before directly accessing the pixels.
363  *
364  * \param surface the SDL_Surface structure to optimize
365  * \param flag 0 to disable, non-zero to enable RLE acceleration
366  * \returns 0 on success or a negative error code on failure; call
367  *          SDL_GetError() for more information.
368  *
369  * \sa SDL_BlitSurface
370  * \sa SDL_LockSurface
371  * \sa SDL_UnlockSurface
372  */
373 extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface,
374                                               int flag);
375 
376 /**
377  * Returns whether the surface is RLE enabled
378  *
379  * It is safe to pass a NULL `surface` here; it will return SDL_FALSE.
380  *
381  * \param surface the SDL_Surface structure to query
382  * \returns SDL_TRUE if the surface is RLE enabled, SDL_FALSE otherwise.
383  *
384  * \sa SDL_SetSurfaceRLE
385  */
386 extern DECLSPEC SDL_bool SDLCALL SDL_HasSurfaceRLE(SDL_Surface * surface);
387 
388 /**
389  * Set the color key (transparent pixel) in a surface.
390  *
391  * The color key defines a pixel value that will be treated as transparent in
392  * a blit. For example, one can use this to specify that cyan pixels should be
393  * considered transparent, and therefore not rendered.
394  *
395  * It is a pixel of the format used by the surface, as generated by
396  * SDL_MapRGB().
397  *
398  * RLE acceleration can substantially speed up blitting of images with large
399  * horizontal runs of transparent pixels. See SDL_SetSurfaceRLE() for details.
400  *
401  * \param surface the SDL_Surface structure to update
402  * \param flag SDL_TRUE to enable color key, SDL_FALSE to disable color key
403  * \param key the transparent pixel
404  * \returns 0 on success or a negative error code on failure; call
405  *          SDL_GetError() for more information.
406  *
407  * \sa SDL_BlitSurface
408  * \sa SDL_GetColorKey
409  */
410 extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface,
411                                             int flag, Uint32 key);
412 
413 /**
414  * Returns whether the surface has a color key
415  *
416  * It is safe to pass a NULL `surface` here; it will return SDL_FALSE.
417  *
418  * \param surface the SDL_Surface structure to query
419  * \return SDL_TRUE if the surface has a color key, SDL_FALSE otherwise.
420  *
421  * \sa SDL_SetColorKey
422  * \sa SDL_GetColorKey
423  */
424 extern DECLSPEC SDL_bool SDLCALL SDL_HasColorKey(SDL_Surface * surface);
425 
426 /**
427  * Get the color key (transparent pixel) for a surface.
428  *
429  * The color key is a pixel of the format used by the surface, as generated by
430  * SDL_MapRGB().
431  *
432  * If the surface doesn't have color key enabled this function returns -1.
433  *
434  * \param surface the SDL_Surface structure to query
435  * \param key a pointer filled in with the transparent pixel
436  * \returns 0 on success or a negative error code on failure; call
437  *          SDL_GetError() for more information.
438  *
439  * \sa SDL_BlitSurface
440  * \sa SDL_SetColorKey
441  */
442 extern DECLSPEC int SDLCALL SDL_GetColorKey(SDL_Surface * surface,
443                                             Uint32 * key);
444 
445 /**
446  * Set an additional color value multiplied into blit operations.
447  *
448  * When this surface is blitted, during the blit operation each source color
449  * channel is modulated by the appropriate color value according to the
450  * following formula:
451  *
452  * `srcC = srcC * (color / 255)`
453  *
454  * \param surface the SDL_Surface structure to update
455  * \param r the red color value multiplied into blit operations
456  * \param g the green color value multiplied into blit operations
457  * \param b the blue color value multiplied into blit operations
458  * \returns 0 on success or a negative error code on failure; call
459  *          SDL_GetError() for more information.
460  *
461  * \sa SDL_GetSurfaceColorMod
462  * \sa SDL_SetSurfaceAlphaMod
463  */
464 extern DECLSPEC int SDLCALL SDL_SetSurfaceColorMod(SDL_Surface * surface,
465                                                    Uint8 r, Uint8 g, Uint8 b);
466 
467 
468 /**
469  * Get the additional color value multiplied into blit operations.
470  *
471  * \param surface the SDL_Surface structure to query
472  * \param r a pointer filled in with the current red color value
473  * \param g a pointer filled in with the current green color value
474  * \param b a pointer filled in with the current blue color value
475  * \returns 0 on success or a negative error code on failure; call
476  *          SDL_GetError() for more information.
477  *
478  * \sa SDL_GetSurfaceAlphaMod
479  * \sa SDL_SetSurfaceColorMod
480  */
481 extern DECLSPEC int SDLCALL SDL_GetSurfaceColorMod(SDL_Surface * surface,
482                                                    Uint8 * r, Uint8 * g,
483                                                    Uint8 * b);
484 
485 /**
486  * Set an additional alpha value used in blit operations.
487  *
488  * When this surface is blitted, during the blit operation the source alpha
489  * value is modulated by this alpha value according to the following formula:
490  *
491  * `srcA = srcA * (alpha / 255)`
492  *
493  * \param surface the SDL_Surface structure to update
494  * \param alpha the alpha value multiplied into blit operations
495  * \returns 0 on success or a negative error code on failure; call
496  *          SDL_GetError() for more information.
497  *
498  * \sa SDL_GetSurfaceAlphaMod
499  * \sa SDL_SetSurfaceColorMod
500  */
501 extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface * surface,
502                                                    Uint8 alpha);
503 
504 /**
505  * Get the additional alpha value used in blit operations.
506  *
507  * \param surface the SDL_Surface structure to query
508  * \param alpha a pointer filled in with the current alpha value
509  * \returns 0 on success or a negative error code on failure; call
510  *          SDL_GetError() for more information.
511  *
512  * \sa SDL_GetSurfaceColorMod
513  * \sa SDL_SetSurfaceAlphaMod
514  */
515 extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface * surface,
516                                                    Uint8 * alpha);
517 
518 /**
519  * Set the blend mode used for blit operations.
520  *
521  * To copy a surface to another surface (or texture) without blending with the
522  * existing data, the blendmode of the SOURCE surface should be set to
523  * `SDL_BLENDMODE_NONE`.
524  *
525  * \param surface the SDL_Surface structure to update
526  * \param blendMode the SDL_BlendMode to use for blit blending
527  * \returns 0 on success or a negative error code on failure; call
528  *          SDL_GetError() for more information.
529  *
530  * \sa SDL_GetSurfaceBlendMode
531  */
532 extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface * surface,
533                                                     SDL_BlendMode blendMode);
534 
535 /**
536  * Get the blend mode used for blit operations.
537  *
538  * \param surface the SDL_Surface structure to query
539  * \param blendMode a pointer filled in with the current SDL_BlendMode
540  * \returns 0 on success or a negative error code on failure; call
541  *          SDL_GetError() for more information.
542  *
543  * \sa SDL_SetSurfaceBlendMode
544  */
545 extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface * surface,
546                                                     SDL_BlendMode *blendMode);
547 
548 /**
549  * Set the clipping rectangle for a surface.
550  *
551  * When `surface` is the destination of a blit, only the area within the clip
552  * rectangle is drawn into.
553  *
554  * Note that blits are automatically clipped to the edges of the source and
555  * destination surfaces.
556  *
557  * \param surface the SDL_Surface structure to be clipped
558  * \param rect the SDL_Rect structure representing the clipping rectangle, or
559  *             NULL to disable clipping
560  * \returns SDL_TRUE if the rectangle intersects the surface, otherwise
561  *          SDL_FALSE and blits will be completely clipped.
562  *
563  * \sa SDL_BlitSurface
564  * \sa SDL_GetClipRect
565  */
566 extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface * surface,
567                                                  const SDL_Rect * rect);
568 
569 /**
570  * Get the clipping rectangle for a surface.
571  *
572  * When `surface` is the destination of a blit, only the area within the clip
573  * rectangle is drawn into.
574  *
575  * \param surface the SDL_Surface structure representing the surface to be
576  *                clipped
577  * \param rect an SDL_Rect structure filled in with the clipping rectangle for
578  *             the surface
579  *
580  * \sa SDL_BlitSurface
581  * \sa SDL_SetClipRect
582  */
583 extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface,
584                                              SDL_Rect * rect);
585 
586 /*
587  * Creates a new surface identical to the existing surface.
588  *
589  * The returned surface should be freed with SDL_FreeSurface().
590  *
591  * \param surface the surface to duplicate.
592  * \returns a copy of the surface, or NULL on failure; call SDL_GetError() for
593  *          more information.
594  */
595 extern DECLSPEC SDL_Surface *SDLCALL SDL_DuplicateSurface(SDL_Surface * surface);
596 
597 /**
598  * Copy an existing surface to a new surface of the specified format.
599  *
600  * This function is used to optimize images for faster *repeat* blitting. This
601  * is accomplished by converting the original and storing the result as a new
602  * surface. The new, optimized surface can then be used as the source for
603  * future blits, making them faster.
604  *
605  * \param src the existing SDL_Surface structure to convert
606  * \param fmt the SDL_PixelFormat structure that the new surface is optimized
607  *            for
608  * \param flags the flags are unused and should be set to 0; this is a
609  *              leftover from SDL 1.2's API
610  * \returns the new SDL_Surface structure that is created or NULL if it fails;
611  *          call SDL_GetError() for more information.
612  *
613  * \sa SDL_AllocFormat
614  * \sa SDL_ConvertSurfaceFormat
615  * \sa SDL_CreateRGBSurface
616  */
617 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface
618     (SDL_Surface * src, const SDL_PixelFormat * fmt, Uint32 flags);
619 
620 /**
621  * Copy an existing surface to a new surface of the specified format enum.
622  *
623  * This function operates just like SDL_ConvertSurface(), but accepts an
624  * SDL_PixelFormatEnum value instead of an SDL_PixelFormat structure. As such,
625  * it might be easier to call but it doesn't have access to palette
626  * information for the destination surface, in case that would be important.
627  *
628  * \param src the existing SDL_Surface structure to convert
629  * \param pixel_format the SDL_PixelFormatEnum that the new surface is
630  *                     optimized for
631  * \param flags the flags are unused and should be set to 0; this is a
632  *              leftover from SDL 1.2's API
633  * \returns the new SDL_Surface structure that is created or NULL if it fails;
634  *          call SDL_GetError() for more information.
635  *
636  * \sa SDL_AllocFormat
637  * \sa SDL_ConvertSurfaceFormat
638  * \sa SDL_CreateRGBSurface
639  */
640 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurfaceFormat
641     (SDL_Surface * src, Uint32 pixel_format, Uint32 flags);
642 
643 /**
644  * Copy a block of pixels of one format to another format.
645  *
646  * \param width the width of the block to copy, in pixels
647  * \param height the height of the block to copy, in pixels
648  * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format
649  * \param src a pointer to the source pixels
650  * \param src_pitch the pitch of the block to copy, in bytes
651  * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format
652  * \param dst a pointer to be filled in with new pixel data
653  * \param dst_pitch the pitch of the destination pixels, in bytes
654  * \returns 0 on success or a negative error code on failure; call
655  *          SDL_GetError() for more information.
656  */
657 extern DECLSPEC int SDLCALL SDL_ConvertPixels(int width, int height,
658                                               Uint32 src_format,
659                                               const void * src, int src_pitch,
660                                               Uint32 dst_format,
661                                               void * dst, int dst_pitch);
662 
663 /**
664  * Perform a fast fill of a rectangle with a specific color.
665  *
666  * `color` should be a pixel of the format used by the surface, and can be
667  * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an
668  * alpha component then the destination is simply filled with that alpha
669  * information, no blending takes place.
670  *
671  * If there is a clip rectangle set on the destination (set via
672  * SDL_SetClipRect()), then this function will fill based on the intersection
673  * of the clip rectangle and `rect`.
674  *
675  * \param dst the SDL_Surface structure that is the drawing target
676  * \param rect the SDL_Rect structure representing the rectangle to fill, or
677  *             NULL to fill the entire surface
678  * \param color the color to fill with
679  * \returns 0 on success or a negative error code on failure; call
680  *          SDL_GetError() for more information.
681  *
682  * \sa SDL_FillRects
683  */
684 extern DECLSPEC int SDLCALL SDL_FillRect
685     (SDL_Surface * dst, const SDL_Rect * rect, Uint32 color);
686 
687 /**
688  * Perform a fast fill of a set of rectangles with a specific color.
689  *
690  * `color` should be a pixel of the format used by the surface, and can be
691  * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an
692  * alpha component then the destination is simply filled with that alpha
693  * information, no blending takes place.
694  *
695  * If there is a clip rectangle set on the destination (set via
696  * SDL_SetClipRect()), then this function will fill based on the intersection
697  * of the clip rectangle and `rect`.
698  *
699  * \param dst the SDL_Surface structure that is the drawing target
700  * \param rects an array of SDL_Rects representing the rectangles to fill.
701  * \param count the number of rectangles in the array
702  * \param color the color to fill with
703  * \returns 0 on success or a negative error code on failure; call
704  *          SDL_GetError() for more information.
705  *
706  * \sa SDL_FillRect
707  */
708 extern DECLSPEC int SDLCALL SDL_FillRects
709     (SDL_Surface * dst, const SDL_Rect * rects, int count, Uint32 color);
710 
711 /* !!! FIXME: merge this documentation with the wiki */
712 /**
713  *  Performs a fast blit from the source surface to the destination surface.
714  *
715  *  This assumes that the source and destination rectangles are
716  *  the same size.  If either \c srcrect or \c dstrect are NULL, the entire
717  *  surface (\c src or \c dst) is copied.  The final blit rectangles are saved
718  *  in \c srcrect and \c dstrect after all clipping is performed.
719  *
720  *  \returns 0 if the blit is successful, otherwise it returns -1.
721  *
722  *  The blit function should not be called on a locked surface.
723  *
724  *  The blit semantics for surfaces with and without blending and colorkey
725  *  are defined as follows:
726  *  \verbatim
727     RGBA->RGB:
728       Source surface blend mode set to SDL_BLENDMODE_BLEND:
729         alpha-blend (using the source alpha-channel and per-surface alpha)
730         SDL_SRCCOLORKEY ignored.
731       Source surface blend mode set to SDL_BLENDMODE_NONE:
732         copy RGB.
733         if SDL_SRCCOLORKEY set, only copy the pixels matching the
734         RGB values of the source color key, ignoring alpha in the
735         comparison.
736 
737     RGB->RGBA:
738       Source surface blend mode set to SDL_BLENDMODE_BLEND:
739         alpha-blend (using the source per-surface alpha)
740       Source surface blend mode set to SDL_BLENDMODE_NONE:
741         copy RGB, set destination alpha to source per-surface alpha value.
742       both:
743         if SDL_SRCCOLORKEY set, only copy the pixels matching the
744         source color key.
745 
746     RGBA->RGBA:
747       Source surface blend mode set to SDL_BLENDMODE_BLEND:
748         alpha-blend (using the source alpha-channel and per-surface alpha)
749         SDL_SRCCOLORKEY ignored.
750       Source surface blend mode set to SDL_BLENDMODE_NONE:
751         copy all of RGBA to the destination.
752         if SDL_SRCCOLORKEY set, only copy the pixels matching the
753         RGB values of the source color key, ignoring alpha in the
754         comparison.
755 
756     RGB->RGB:
757       Source surface blend mode set to SDL_BLENDMODE_BLEND:
758         alpha-blend (using the source per-surface alpha)
759       Source surface blend mode set to SDL_BLENDMODE_NONE:
760         copy RGB.
761       both:
762         if SDL_SRCCOLORKEY set, only copy the pixels matching the
763         source color key.
764     \endverbatim
765  *
766  *  You should call SDL_BlitSurface() unless you know exactly how SDL
767  *  blitting works internally and how to use the other blit functions.
768  */
769 #define SDL_BlitSurface SDL_UpperBlit
770 
771 /**
772  * Perform a fast blit from the source surface to the destination surface.
773  *
774  * SDL_UpperBlit() has been replaced by SDL_BlitSurface(), which is merely a
775  * macro for this function with a less confusing name.
776  *
777  * \sa SDL_BlitSurface
778  */
779 extern DECLSPEC int SDLCALL SDL_UpperBlit
780     (SDL_Surface * src, const SDL_Rect * srcrect,
781      SDL_Surface * dst, SDL_Rect * dstrect);
782 
783 /**
784  * Perform low-level surface blitting only.
785  *
786  * This is a semi-private blit function and it performs low-level surface
787  * blitting, assuming the input rectangles have already been clipped.
788  *
789  * Unless you know what you're doing, you should be using SDL_BlitSurface()
790  * instead.
791  *
792  * \param src the SDL_Surface structure to be copied from
793  * \param srcrect the SDL_Rect structure representing the rectangle to be
794  *                copied, or NULL to copy the entire surface
795  * \param dst the SDL_Surface structure that is the blit target
796  * \param dstrect the SDL_Rect structure representing the rectangle that is
797  *                copied into
798  * \returns 0 on success or a negative error code on failure; call
799  *          SDL_GetError() for more information.
800  *
801  * \sa SDL_BlitSurface
802  */
803 extern DECLSPEC int SDLCALL SDL_LowerBlit
804     (SDL_Surface * src, SDL_Rect * srcrect,
805      SDL_Surface * dst, SDL_Rect * dstrect);
806 
807 
808  /**
809   * Perform a fast, low quality, stretch blit between two surfaces of the
810   * same format.
811   *
812   * Please use SDL_BlitScaled() instead.
813   */
814 extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src,
815                                             const SDL_Rect * srcrect,
816                                             SDL_Surface * dst,
817                                             const SDL_Rect * dstrect);
818 
819 /**
820  * Perform bilinear scaling between two surfaces of the same format, 32BPP.
821  */
822 extern DECLSPEC int SDLCALL SDL_SoftStretchLinear(SDL_Surface * src,
823                                             const SDL_Rect * srcrect,
824                                             SDL_Surface * dst,
825                                             const SDL_Rect * dstrect);
826 
827 
828 #define SDL_BlitScaled SDL_UpperBlitScaled
829 
830 /**
831  * Perform a scaled surface copy to a destination surface.
832  *
833  * SDL_UpperBlitScaled() has been replaced by SDL_BlitScaled(), which is
834  * merely a macro for this function with a less confusing name.
835  *
836  * \sa SDL_BlitScaled
837  */
838 extern DECLSPEC int SDLCALL SDL_UpperBlitScaled
839     (SDL_Surface * src, const SDL_Rect * srcrect,
840     SDL_Surface * dst, SDL_Rect * dstrect);
841 
842 /**
843  * Perform low-level surface scaled blitting only.
844  *
845  * This is a semi-private function and it performs low-level surface blitting,
846  * assuming the input rectangles have already been clipped.
847  *
848  * \param src the SDL_Surface structure to be copied from
849  * \param srcrect the SDL_Rect structure representing the rectangle to be
850  *                copied
851  * \param dst the SDL_Surface structure that is the blit target
852  * \param dstrect the SDL_Rect structure representing the rectangle that is
853  *                copied into
854  * \returns 0 on success or a negative error code on failure; call
855  *          SDL_GetError() for more information.
856  *
857  * \sa SDL_BlitScaled
858  */
859 extern DECLSPEC int SDLCALL SDL_LowerBlitScaled
860     (SDL_Surface * src, SDL_Rect * srcrect,
861     SDL_Surface * dst, SDL_Rect * dstrect);
862 
863 /**
864  * Set the YUV conversion mode
865  */
866 extern DECLSPEC void SDLCALL SDL_SetYUVConversionMode(SDL_YUV_CONVERSION_MODE mode);
867 
868 /**
869  * Get the YUV conversion mode
870  */
871 extern DECLSPEC SDL_YUV_CONVERSION_MODE SDLCALL SDL_GetYUVConversionMode(void);
872 
873 /**
874  * Get the YUV conversion mode, returning the correct mode for the resolution
875  * when the current conversion mode is SDL_YUV_CONVERSION_AUTOMATIC
876  */
877 extern DECLSPEC SDL_YUV_CONVERSION_MODE SDLCALL SDL_GetYUVConversionModeForResolution(int width, int height);
878 
879 /* Ends C function definitions when using C++ */
880 #ifdef __cplusplus
881 }
882 #endif
883 #include "close_code.h"
884 
885 #endif /* SDL_surface_h_ */
886 
887 /* vi: set ts=4 sw=4 expandtab: */
888