include/SDL_surface.h
author Sam Lantinga <slouken@libsdl.org>
Mon, 10 Sep 2007 12:20:02 +0000
changeset 2275 12ea0fdc0df2
child 2807 365fe1a2aad5
permissions -rw-r--r--
Split out the SDL_rect and SDL_surface functions into their own headers.
Removed unused count from the dirty rect list.
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997-2006 Sam Lantinga
     4 
     5     This library is free software; you can redistribute it and/or
     6     modify it under the terms of the GNU Lesser General Public
     7     License as published by the Free Software Foundation; either
     8     version 2.1 of the License, or (at your option) any later version.
     9 
    10     This library is distributed in the hope that it will be useful,
    11     but WITHOUT ANY WARRANTY; without even the implied warranty of
    12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    13     Lesser General Public License for more details.
    14 
    15     You should have received a copy of the GNU Lesser General Public
    16     License along with this library; if not, write to the Free Software
    17     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
    18 
    19     Sam Lantinga
    20     slouken@libsdl.org
    21 */
    22 
    23 /**
    24  * \file SDL_surface.h
    25  *
    26  * Header file for SDL_surface definition and management functions
    27  */
    28 
    29 #ifndef _SDL_surface_h
    30 #define _SDL_surface_h
    31 
    32 #include "SDL_stdinc.h"
    33 #include "SDL_pixels.h"
    34 #include "SDL_rect.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 /* *INDENT-OFF* */
    41 extern "C" {
    42 /* *INDENT-ON* */
    43 #endif
    44 
    45 /* These are the currently supported flags for the SDL_surface */
    46 /* Used internally (read-only) */
    47 #define SDL_PREALLOC        0x00000001  /* Surface uses preallocated memory */
    48 #define SDL_RLEACCEL        0x00000002  /* Surface is RLE encoded */
    49 
    50 /* Evaluates to true if the surface needs to be locked before access */
    51 #define SDL_MUSTLOCK(S)	(((S)->flags & SDL_RLEACCEL) != 0)
    52 
    53 /**
    54  * \struct SDL_Surface
    55  *
    56  * \brief A collection of pixels used in software blitting
    57  *
    58  * \note  This structure should be treated as read-only, except for 'pixels',
    59  *        which, if not NULL, contains the raw pixel data for the surface.
    60  */
    61 typedef struct SDL_Surface
    62 {
    63     Uint32 flags;               /**< Read-only */
    64     SDL_PixelFormat *format;    /**< Read-only */
    65     int w, h;                   /**< Read-only */
    66     int pitch;                  /**< Read-only */
    67     void *pixels;               /**< Read-write */
    68 
    69     /* Application data associated with the surfade */
    70     void *userdata;             /**< Read-write */
    71 
    72     /* information needed for surfaces requiring locks */
    73     int locked;                 /**< Read-only */
    74     void *lock_data;            /**< Read-only */
    75 
    76     /* clipping information */
    77     SDL_Rect clip_rect;         /**< Read-only */
    78 
    79     /* info for fast blit mapping to other surfaces */
    80     struct SDL_BlitMap *map;    /**< Private */
    81 
    82     /* format version, bumped at every change to invalidate blit maps */
    83     unsigned int format_version;        /**< Private */
    84 
    85     /* Reference count -- used when freeing surface */
    86     int refcount;               /**< Read-mostly */
    87 } SDL_Surface;
    88 
    89 /**
    90  * \typedef SDL_blit
    91  *
    92  * \brief The type of function used for surface blitting functions
    93  */
    94 typedef int (*SDL_blit) (struct SDL_Surface * src, SDL_Rect * srcrect,
    95                          struct SDL_Surface * dst, SDL_Rect * dstrect);
    96 
    97 /*
    98  * Allocate and free an RGB surface (must be called after SDL_SetVideoMode)
    99  * If the depth is 4 or 8 bits, an empty palette is allocated for the surface.
   100  * If the depth is greater than 8 bits, the pixel format is set using the
   101  * flags '[RGB]mask'.
   102  * If the function runs out of memory, it will return NULL.
   103  *
   104  * The 'flags' tell what kind of surface to create.
   105  * SDL_SRCCOLORKEY indicates that the surface will be used for colorkey blits.
   106  * SDL_SRCALPHA means that the surface will be used for alpha blits.
   107  */
   108 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface
   109     (Uint32 flags, int width, int height, int depth,
   110      Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
   111 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels,
   112                                                               int width,
   113                                                               int height,
   114                                                               int depth,
   115                                                               int pitch,
   116                                                               Uint32 Rmask,
   117                                                               Uint32 Gmask,
   118                                                               Uint32 Bmask,
   119                                                               Uint32 Amask);
   120 extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface);
   121 
   122 /**
   123  * \fn int SDL_SetSurfacePalette(SDL_Surface *surface, SDL_Palette *palette)
   124  *
   125  * \brief Set the palette used by a surface.
   126  *
   127  * \return 0, or -1 if the surface format doesn't use a palette.
   128  *
   129  * \note A single palette can be shared with many surfaces.
   130  */
   131 extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface,
   132                                                   SDL_Palette * palette);
   133 
   134 /*
   135  * SDL_LockSurface() sets up a surface for directly accessing the pixels.
   136  * Between calls to SDL_LockSurface()/SDL_UnlockSurface(), you can write
   137  * to and read from 'surface->pixels', using the pixel format stored in 
   138  * 'surface->format'.  Once you are done accessing the surface, you should 
   139  * use SDL_UnlockSurface() to release it.
   140  *
   141  * Not all surfaces require locking.  If SDL_MUSTLOCK(surface) evaluates
   142  * to 0, then you can read and write to the surface at any time, and the
   143  * pixel format of the surface will not change.
   144  * 
   145  * No operating system or library calls should be made between lock/unlock
   146  * pairs, as critical system locks may be held during this time.
   147  *
   148  * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked.
   149  */
   150 extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface);
   151 extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface);
   152 
   153 /*
   154  * Load a surface from a seekable SDL data source (memory or file.)
   155  * If 'freesrc' is non-zero, the source will be closed after being read.
   156  * Returns the new surface, or NULL if there was an error.
   157  * The new surface should be freed with SDL_FreeSurface().
   158  */
   159 extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src,
   160                                                     int freesrc);
   161 
   162 /* Convenience macro -- load a surface from a file */
   163 #define SDL_LoadBMP(file)	SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1)
   164 
   165 /*
   166  * Save a surface to a seekable SDL data source (memory or file.)
   167  * If 'freedst' is non-zero, the source will be closed after being written.
   168  * Returns 0 if successful or -1 if there was an error.
   169  */
   170 extern DECLSPEC int SDLCALL SDL_SaveBMP_RW
   171     (SDL_Surface * surface, SDL_RWops * dst, int freedst);
   172 
   173 /* Convenience macro -- save a surface to a file */
   174 #define SDL_SaveBMP(surface, file) \
   175 		SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1)
   176 
   177 /*
   178  * \fn int SDL_SetSurfaceRLE(SDL_Surface *surface, int flag)
   179  *
   180  * \brief Sets the RLE acceleration hint for a surface.
   181  *
   182  * \return 0 on success, or -1 if the surface is not valid
   183  *
   184  * \note If RLE is enabled, colorkey and alpha blending blits are much faster,
   185  *       but the surface must be locked before directly accessing the pixels.
   186  */
   187 extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface,
   188                                               int flag);
   189 
   190 /*
   191  * \fn int SDL_SetColorKey(SDL_Surface *surface, Uint32 flag, Uint32 key)
   192  *
   193  * \brief Sets the color key (transparent pixel) in a blittable surface.
   194  *
   195  * \param surface The surface to update
   196  * \param flag Non-zero to enable colorkey and 0 to disable colorkey 
   197  * \param key The transparent pixel in the native surface format
   198  *
   199  * \return 0 on success, or -1 if the surface is not valid
   200  */
   201 extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface,
   202                                             Uint32 flag, Uint32 key);
   203 
   204 /**
   205  * \fn int SDL_SetSurfaceColorMod(SDL_Surface *surface, Uint8 r, Uint8 g, Uint8 b)
   206  *
   207  * \brief Set an additional color value used in blit operations
   208  *
   209  * \param surface The surface to update
   210  * \param r The red source color value multiplied into blit operations
   211  * \param g The green source color value multiplied into blit operations
   212  * \param b The blue source color value multiplied into blit operations
   213  *
   214  * \return 0 on success, or -1 if the surface is not valid
   215  *
   216  * \sa SDL_GetSurfaceColorMod()
   217  */
   218 extern DECLSPEC int SDLCALL SDL_SetSurfaceColorMod(SDL_Surface * surface,
   219                                                    Uint8 r, Uint8 g, Uint8 b);
   220 
   221 
   222 /**
   223  * \fn int SDL_GetSurfaceColorMod(SDL_Surface *surface, Uint8 *r, Uint8 *g, Uint8 *b)
   224  *
   225  * \brief Get the additional color value used in blit operations
   226  *
   227  * \param surface The surface to query
   228  * \param r A pointer filled in with the source red color value
   229  * \param g A pointer filled in with the source green color value
   230  * \param b A pointer filled in with the source blue color value
   231  *
   232  * \return 0 on success, or -1 if the surface is not valid
   233  *
   234  * \sa SDL_SetSurfaceColorMod()
   235  */
   236 extern DECLSPEC int SDLCALL SDL_GetSurfaceColorMod(SDL_Surface * surface,
   237                                                    Uint8 * r, Uint8 * g,
   238                                                    Uint8 * b);
   239 
   240 /**
   241  * \fn int SDL_SetSurfaceAlphaMod(SDL_Surface *surface, Uint8 alpha)
   242  *
   243  * \brief Set an additional alpha value used in blit operations
   244  *
   245  * \param surface The surface to update
   246  * \param alpha The source alpha value multiplied into blit operations.
   247  *
   248  * \return 0 on success, or -1 if the surface is not valid
   249  *
   250  * \sa SDL_GetSurfaceAlphaMod()
   251  */
   252 extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface * surface,
   253                                                    Uint8 alpha);
   254 
   255 /**
   256  * \fn int SDL_GetSurfaceAlphaMod(SDL_Surface *surface, Uint8 *alpha)
   257  *
   258  * \brief Get the additional alpha value used in blit operations
   259  *
   260  * \param surface The surface to query
   261  * \param alpha A pointer filled in with the source alpha value
   262  *
   263  * \return 0 on success, or -1 if the surface is not valid
   264  *
   265  * \sa SDL_SetSurfaceAlphaMod()
   266  */
   267 extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface * surface,
   268                                                    Uint8 * alpha);
   269 
   270 /**
   271  * \fn int SDL_SetSurfaceBlendMode(SDL_Surface *surface, int blendMode)
   272  *
   273  * \brief Set the blend mode used for blit operations
   274  *
   275  * \param surface The surface to update
   276  * \param blendMode SDL_TextureBlendMode to use for blit blending
   277  *
   278  * \return 0 on success, or -1 if the parameters are not valid
   279  *
   280  * \sa SDL_GetSurfaceBlendMode()
   281  */
   282 extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface * surface,
   283                                                     int blendMode);
   284 
   285 /**
   286  * \fn int SDL_GetSurfaceBlendMode(SDL_Surface *surface, int *blendMode)
   287  *
   288  * \brief Get the blend mode used for blit operations
   289  *
   290  * \param surface The surface to query
   291  * \param blendMode A pointer filled in with the current blend mode
   292  *
   293  * \return 0 on success, or -1 if the surface is not valid
   294  *
   295  * \sa SDL_SetSurfaceBlendMode()
   296  */
   297 extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface * surface,
   298                                                     int *blendMode);
   299 
   300 /**
   301  * \fn int SDL_SetSurfaceScaleMode(SDL_Surface *surface, int scaleMode)
   302  *
   303  * \brief Set the scale mode used for blit operations
   304  *
   305  * \param surface The surface to update
   306  * \param scaleMode SDL_TextureScaleMode to use for blit scaling
   307  *
   308  * \return 0 on success, or -1 if the surface is not valid or the scale mode is not supported
   309  *
   310  * \note If the scale mode is not supported, the closest supported mode is chosen.  Currently only SDL_TEXTURESCALEMODE_FAST is supported on surfaces.
   311  *
   312  * \sa SDL_GetSurfaceScaleMode()
   313  */
   314 extern DECLSPEC int SDLCALL SDL_SetSurfaceScaleMode(SDL_Surface * surface,
   315                                                     int scaleMode);
   316 
   317 /**
   318  * \fn int SDL_GetSurfaceScaleMode(SDL_Surface *surface, int *scaleMode)
   319  *
   320  * \brief Get the scale mode used for blit operations
   321  *
   322  * \param surface The surface to query
   323  * \param scaleMode A pointer filled in with the current scale mode
   324  *
   325  * \return 0 on success, or -1 if the surface is not valid
   326  *
   327  * \sa SDL_SetSurfaceScaleMode()
   328  */
   329 extern DECLSPEC int SDLCALL SDL_GetSurfaceScaleMode(SDL_Surface * surface,
   330                                                     int *scaleMode);
   331 
   332 /*
   333  * Sets the clipping rectangle for the destination surface in a blit.
   334  *
   335  * If the clip rectangle is NULL, clipping will be disabled.
   336  * If the clip rectangle doesn't intersect the surface, the function will
   337  * return SDL_FALSE and blits will be completely clipped.  Otherwise the
   338  * function returns SDL_TRUE and blits to the surface will be clipped to
   339  * the intersection of the surface area and the clipping rectangle.
   340  *
   341  * Note that blits are automatically clipped to the edges of the source
   342  * and destination surfaces.
   343  */
   344 extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface * surface,
   345                                                  const SDL_Rect * rect);
   346 
   347 /*
   348  * Gets the clipping rectangle for the destination surface in a blit.
   349  * 'rect' must be a pointer to a valid rectangle which will be filled
   350  * with the correct values.
   351  */
   352 extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface,
   353                                              SDL_Rect * rect);
   354 
   355 /*
   356  * Creates a new surface of the specified format, and then copies and maps 
   357  * the given surface to it so the blit of the converted surface will be as 
   358  * fast as possible.  If this function fails, it returns NULL.
   359  *
   360  * The 'flags' parameter is passed to SDL_CreateRGBSurface() and has those 
   361  * semantics.  You can also pass SDL_RLEACCEL in the flags parameter and
   362  * SDL will try to RLE accelerate colorkey and alpha blits in the resulting
   363  * surface.
   364  *
   365  * This function is used internally by SDL_DisplayFormat().
   366  */
   367 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface
   368     (SDL_Surface * src, SDL_PixelFormat * fmt, Uint32 flags);
   369 
   370 /*
   371  * This function performs a fast fill of the given rectangle with 'color'
   372  * The given rectangle is clipped to the destination surface clip area
   373  * and the final fill rectangle is saved in the passed in pointer.
   374  * If 'dstrect' is NULL, the whole surface will be filled with 'color'
   375  * The color should be a pixel of the format used by the surface, and 
   376  * can be generated by the SDL_MapRGB() function.
   377  * This function returns 0 on success, or -1 on error.
   378  */
   379 extern DECLSPEC int SDLCALL SDL_FillRect
   380     (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color);
   381 
   382 /*
   383  * This performs a fast blit from the source surface to the destination
   384  * surface.  It assumes that the source and destination rectangles are
   385  * the same size.  If either 'srcrect' or 'dstrect' are NULL, the entire
   386  * surface (src or dst) is copied.  The final blit rectangles are saved
   387  * in 'srcrect' and 'dstrect' after all clipping is performed.
   388  * If the blit is successful, it returns 0, otherwise it returns -1.
   389  *
   390  * The blit function should not be called on a locked surface.
   391  *
   392  * The blit semantics for surfaces with and without alpha and colorkey
   393  * are defined as follows:
   394  *
   395  * RGBA->RGB:
   396  *     SDL_SRCALPHA set:
   397  * 	alpha-blend (using alpha-channel).
   398  * 	SDL_SRCCOLORKEY ignored.
   399  *     SDL_SRCALPHA not set:
   400  * 	copy RGB.
   401  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
   402  * 	RGB values of the source colour key, ignoring alpha in the
   403  * 	comparison.
   404  * 
   405  * RGB->RGBA:
   406  *     SDL_SRCALPHA set:
   407  * 	alpha-blend (using the source per-surface alpha value);
   408  * 	set destination alpha to opaque.
   409  *     SDL_SRCALPHA not set:
   410  * 	copy RGB, set destination alpha to source per-surface alpha value.
   411  *     both:
   412  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
   413  * 	source colour key.
   414  * 
   415  * RGBA->RGBA:
   416  *     SDL_SRCALPHA set:
   417  * 	alpha-blend (using the source alpha channel) the RGB values;
   418  * 	leave destination alpha untouched. [Note: is this correct?]
   419  * 	SDL_SRCCOLORKEY ignored.
   420  *     SDL_SRCALPHA not set:
   421  * 	copy all of RGBA to the destination.
   422  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
   423  * 	RGB values of the source colour key, ignoring alpha in the
   424  * 	comparison.
   425  * 
   426  * RGB->RGB: 
   427  *     SDL_SRCALPHA set:
   428  * 	alpha-blend (using the source per-surface alpha value).
   429  *     SDL_SRCALPHA not set:
   430  * 	copy RGB.
   431  *     both:
   432  * 	if SDL_SRCCOLORKEY set, only copy the pixels matching the
   433  * 	source colour key.
   434  *
   435  * If either of the surfaces were in video memory, and the blit returns -2,
   436  * the video memory was lost, so it should be reloaded with artwork and 
   437  * re-blitted:
   438 	while ( SDL_BlitSurface(image, imgrect, screen, dstrect) == -2 ) {
   439 		while ( SDL_LockSurface(image) < 0 )
   440 			Sleep(10);
   441 		-- Write image pixels to image->pixels --
   442 		SDL_UnlockSurface(image);
   443 	}
   444  * This happens under DirectX 5.0 when the system switches away from your
   445  * fullscreen application.  The lock will also fail until you have access
   446  * to the video memory again.
   447  */
   448 /* You should call SDL_BlitSurface() unless you know exactly how SDL
   449    blitting works internally and how to use the other blit functions.
   450 */
   451 #define SDL_BlitSurface SDL_UpperBlit
   452 
   453 /* This is the public blit function, SDL_BlitSurface(), and it performs
   454    rectangle validation and clipping before passing it to SDL_LowerBlit()
   455 */
   456 extern DECLSPEC int SDLCALL SDL_UpperBlit
   457     (SDL_Surface * src, SDL_Rect * srcrect,
   458      SDL_Surface * dst, SDL_Rect * dstrect);
   459 /* This is a semi-private blit function and it performs low-level surface
   460    blitting only.
   461 */
   462 extern DECLSPEC int SDLCALL SDL_LowerBlit
   463     (SDL_Surface * src, SDL_Rect * srcrect,
   464      SDL_Surface * dst, SDL_Rect * dstrect);
   465 
   466 /**
   467  * \fn int SDL_SoftStretch(SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect)
   468  *
   469  * \brief Perform a fast, low quality, stretch blit between two surfaces of the same pixel format.
   470  *
   471  * \note This function uses a static buffer, and is not thread-safe.
   472  */
   473 extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src,
   474                                             SDL_Rect * srcrect,
   475                                             SDL_Surface * dst,
   476                                             SDL_Rect * dstrect);
   477 
   478 /* Ends C function definitions when using C++ */
   479 #ifdef __cplusplus
   480 /* *INDENT-OFF* */
   481 }
   482 /* *INDENT-ON* */
   483 #endif
   484 #include "close_code.h"
   485 
   486 #endif /* _SDL_surface_h */
   487 
   488 /* vi: set ts=4 sw=4 expandtab: */