include/SDL_surface.h
author Sam Lantinga <slouken@libsdl.org>
Sat, 09 Sep 2017 08:34:46 -0700
changeset 11479 74650172be10
parent 11289 ca3c2c98f2e1
child 11702 cf166abbde4a
permissions -rw-r--r--
Make sure the libtool archives are installed
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2017 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 /* @} *//* Surface flags */
    57 
    58 /**
    59  *  Evaluates to true if the surface needs to be locked before access.
    60  */
    61 #define SDL_MUSTLOCK(S) (((S)->flags & SDL_RLEACCEL) != 0)
    62 
    63 /**
    64  * \brief A collection of pixels used in software blitting.
    65  *
    66  * \note  This structure should be treated as read-only, except for \c pixels,
    67  *        which, if not NULL, contains the raw pixel data for the surface.
    68  */
    69 typedef struct SDL_Surface
    70 {
    71     Uint32 flags;               /**< Read-only */
    72     SDL_PixelFormat *format;    /**< Read-only */
    73     int w, h;                   /**< Read-only */
    74     int pitch;                  /**< Read-only */
    75     void *pixels;               /**< Read-write */
    76 
    77     /** Application data associated with the surface */
    78     void *userdata;             /**< Read-write */
    79 
    80     /** information needed for surfaces requiring locks */
    81     int locked;                 /**< Read-only */
    82     void *lock_data;            /**< Read-only */
    83 
    84     /** clipping information */
    85     SDL_Rect clip_rect;         /**< Read-only */
    86 
    87     /** info for fast blit mapping to other surfaces */
    88     struct SDL_BlitMap *map;    /**< Private */
    89 
    90     /** Reference count -- used when freeing surface */
    91     int refcount;               /**< Read-mostly */
    92 } SDL_Surface;
    93 
    94 /**
    95  * \brief The type of function used for surface blitting functions.
    96  */
    97 typedef int (SDLCALL *SDL_blit) (struct SDL_Surface * src, SDL_Rect * srcrect,
    98                                  struct SDL_Surface * dst, SDL_Rect * dstrect);
    99 
   100 /**
   101  *  Allocate and free an RGB surface.
   102  *
   103  *  If the depth is 4 or 8 bits, an empty palette is allocated for the surface.
   104  *  If the depth is greater than 8 bits, the pixel format is set using the
   105  *  flags '[RGB]mask'.
   106  *
   107  *  If the function runs out of memory, it will return NULL.
   108  *
   109  *  \param flags The \c flags are obsolete and should be set to 0.
   110  *  \param width The width in pixels of the surface to create.
   111  *  \param height The height in pixels of the surface to create.
   112  *  \param depth The depth in bits of the surface to create.
   113  *  \param Rmask The red mask of the surface to create.
   114  *  \param Gmask The green mask of the surface to create.
   115  *  \param Bmask The blue mask of the surface to create.
   116  *  \param Amask The alpha mask of the surface to create.
   117  */
   118 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface
   119     (Uint32 flags, int width, int height, int depth,
   120      Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
   121 
   122 /* !!! FIXME for 2.1: why does this ask for depth? Format provides that. */
   123 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormat
   124     (Uint32 flags, int width, int height, int depth, Uint32 format);
   125 
   126 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels,
   127                                                               int width,
   128                                                               int height,
   129                                                               int depth,
   130                                                               int pitch,
   131                                                               Uint32 Rmask,
   132                                                               Uint32 Gmask,
   133                                                               Uint32 Bmask,
   134                                                               Uint32 Amask);
   135 extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormatFrom
   136     (void *pixels, int width, int height, int depth, int pitch, Uint32 format);
   137 extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface);
   138 
   139 /**
   140  *  \brief Set the palette used by a surface.
   141  *
   142  *  \return 0, or -1 if the surface format doesn't use a palette.
   143  *
   144  *  \note A single palette can be shared with many surfaces.
   145  */
   146 extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface,
   147                                                   SDL_Palette * palette);
   148 
   149 /**
   150  *  \brief Sets up a surface for directly accessing the pixels.
   151  *
   152  *  Between calls to SDL_LockSurface() / SDL_UnlockSurface(), you can write
   153  *  to and read from \c surface->pixels, using the pixel format stored in
   154  *  \c surface->format.  Once you are done accessing the surface, you should
   155  *  use SDL_UnlockSurface() to release it.
   156  *
   157  *  Not all surfaces require locking.  If SDL_MUSTLOCK(surface) evaluates
   158  *  to 0, then you can read and write to the surface at any time, and the
   159  *  pixel format of the surface will not change.
   160  *
   161  *  No operating system or library calls should be made between lock/unlock
   162  *  pairs, as critical system locks may be held during this time.
   163  *
   164  *  SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked.
   165  *
   166  *  \sa SDL_UnlockSurface()
   167  */
   168 extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface);
   169 /** \sa SDL_LockSurface() */
   170 extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface);
   171 
   172 /**
   173  *  Load a surface from a seekable SDL data stream (memory or file).
   174  *
   175  *  If \c freesrc is non-zero, the stream will be closed after being read.
   176  *
   177  *  The new surface should be freed with SDL_FreeSurface().
   178  *
   179  *  \return the new surface, or NULL if there was an error.
   180  */
   181 extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src,
   182                                                     int freesrc);
   183 
   184 /**
   185  *  Load a surface from a file.
   186  *
   187  *  Convenience macro.
   188  */
   189 #define SDL_LoadBMP(file)   SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1)
   190 
   191 /**
   192  *  Save a surface to a seekable SDL data stream (memory or file).
   193  *
   194  *  Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the
   195  *  BMP directly. Other RGB formats with 8-bit or higher get converted to a
   196  *  24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit
   197  *  surface before they are saved. YUV and paletted 1-bit and 4-bit formats are
   198  *  not supported.
   199  *
   200  *  If \c freedst is non-zero, the stream will be closed after being written.
   201  *
   202  *  \return 0 if successful or -1 if there was an error.
   203  */
   204 extern DECLSPEC int SDLCALL SDL_SaveBMP_RW
   205     (SDL_Surface * surface, SDL_RWops * dst, int freedst);
   206 
   207 /**
   208  *  Save a surface to a file.
   209  *
   210  *  Convenience macro.
   211  */
   212 #define SDL_SaveBMP(surface, file) \
   213         SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1)
   214 
   215 /**
   216  *  \brief Sets the RLE acceleration hint for a surface.
   217  *
   218  *  \return 0 on success, or -1 if the surface is not valid
   219  *
   220  *  \note If RLE is enabled, colorkey and alpha blending blits are much faster,
   221  *        but the surface must be locked before directly accessing the pixels.
   222  */
   223 extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface,
   224                                               int flag);
   225 
   226 /**
   227  *  \brief Sets the color key (transparent pixel) in a blittable surface.
   228  *
   229  *  \param surface The surface to update
   230  *  \param flag Non-zero to enable colorkey and 0 to disable colorkey
   231  *  \param key The transparent pixel in the native surface format
   232  *
   233  *  \return 0 on success, or -1 if the surface is not valid
   234  *
   235  *  You can pass SDL_RLEACCEL to enable RLE accelerated blits.
   236  */
   237 extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface,
   238                                             int flag, Uint32 key);
   239 
   240 /**
   241  *  \brief Gets the color key (transparent pixel) in a blittable surface.
   242  *
   243  *  \param surface The surface to update
   244  *  \param key A pointer filled in with the transparent pixel in the native
   245  *             surface format
   246  *
   247  *  \return 0 on success, or -1 if the surface is not valid or colorkey is not
   248  *          enabled.
   249  */
   250 extern DECLSPEC int SDLCALL SDL_GetColorKey(SDL_Surface * surface,
   251                                             Uint32 * key);
   252 
   253 /**
   254  *  \brief Set an additional color value used in blit operations.
   255  *
   256  *  \param surface The surface to update.
   257  *  \param r The red color value multiplied into blit operations.
   258  *  \param g The green color value multiplied into blit operations.
   259  *  \param b The blue color value multiplied into blit operations.
   260  *
   261  *  \return 0 on success, or -1 if the surface is not valid.
   262  *
   263  *  \sa SDL_GetSurfaceColorMod()
   264  */
   265 extern DECLSPEC int SDLCALL SDL_SetSurfaceColorMod(SDL_Surface * surface,
   266                                                    Uint8 r, Uint8 g, Uint8 b);
   267 
   268 
   269 /**
   270  *  \brief Get the additional color value used in blit operations.
   271  *
   272  *  \param surface The surface to query.
   273  *  \param r A pointer filled in with the current red color value.
   274  *  \param g A pointer filled in with the current green color value.
   275  *  \param b A pointer filled in with the current blue color value.
   276  *
   277  *  \return 0 on success, or -1 if the surface is not valid.
   278  *
   279  *  \sa SDL_SetSurfaceColorMod()
   280  */
   281 extern DECLSPEC int SDLCALL SDL_GetSurfaceColorMod(SDL_Surface * surface,
   282                                                    Uint8 * r, Uint8 * g,
   283                                                    Uint8 * b);
   284 
   285 /**
   286  *  \brief Set an additional alpha value used in blit operations.
   287  *
   288  *  \param surface The surface to update.
   289  *  \param alpha The alpha value multiplied into blit operations.
   290  *
   291  *  \return 0 on success, or -1 if the surface is not valid.
   292  *
   293  *  \sa SDL_GetSurfaceAlphaMod()
   294  */
   295 extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface * surface,
   296                                                    Uint8 alpha);
   297 
   298 /**
   299  *  \brief Get the additional alpha value used in blit operations.
   300  *
   301  *  \param surface The surface to query.
   302  *  \param alpha A pointer filled in with the current alpha value.
   303  *
   304  *  \return 0 on success, or -1 if the surface is not valid.
   305  *
   306  *  \sa SDL_SetSurfaceAlphaMod()
   307  */
   308 extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface * surface,
   309                                                    Uint8 * alpha);
   310 
   311 /**
   312  *  \brief Set the blend mode used for blit operations.
   313  *
   314  *  \param surface The surface to update.
   315  *  \param blendMode ::SDL_BlendMode to use for blit blending.
   316  *
   317  *  \return 0 on success, or -1 if the parameters are not valid.
   318  *
   319  *  \sa SDL_GetSurfaceBlendMode()
   320  */
   321 extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface * surface,
   322                                                     SDL_BlendMode blendMode);
   323 
   324 /**
   325  *  \brief Get the blend mode used for blit operations.
   326  *
   327  *  \param surface   The surface to query.
   328  *  \param blendMode A pointer filled in with the current blend mode.
   329  *
   330  *  \return 0 on success, or -1 if the surface is not valid.
   331  *
   332  *  \sa SDL_SetSurfaceBlendMode()
   333  */
   334 extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface * surface,
   335                                                     SDL_BlendMode *blendMode);
   336 
   337 /**
   338  *  Sets the clipping rectangle for the destination surface in a blit.
   339  *
   340  *  If the clip rectangle is NULL, clipping will be disabled.
   341  *
   342  *  If the clip rectangle doesn't intersect the surface, the function will
   343  *  return SDL_FALSE and blits will be completely clipped.  Otherwise the
   344  *  function returns SDL_TRUE and blits to the surface will be clipped to
   345  *  the intersection of the surface area and the clipping rectangle.
   346  *
   347  *  Note that blits are automatically clipped to the edges of the source
   348  *  and destination surfaces.
   349  */
   350 extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface * surface,
   351                                                  const SDL_Rect * rect);
   352 
   353 /**
   354  *  Gets the clipping rectangle for the destination surface in a blit.
   355  *
   356  *  \c rect must be a pointer to a valid rectangle which will be filled
   357  *  with the correct values.
   358  */
   359 extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface,
   360                                              SDL_Rect * rect);
   361 
   362 /*
   363  * Creates a new surface identical to the existing surface
   364  */
   365 extern DECLSPEC SDL_Surface *SDLCALL SDL_DuplicateSurface(SDL_Surface * surface);
   366 
   367 /**
   368  *  Creates a new surface of the specified format, and then copies and maps
   369  *  the given surface to it so the blit of the converted surface will be as
   370  *  fast as possible.  If this function fails, it returns NULL.
   371  *
   372  *  The \c flags parameter is passed to SDL_CreateRGBSurface() and has those
   373  *  semantics.  You can also pass ::SDL_RLEACCEL in the flags parameter and
   374  *  SDL will try to RLE accelerate colorkey and alpha blits in the resulting
   375  *  surface.
   376  */
   377 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface
   378     (SDL_Surface * src, const SDL_PixelFormat * fmt, Uint32 flags);
   379 extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurfaceFormat
   380     (SDL_Surface * src, Uint32 pixel_format, Uint32 flags);
   381 
   382 /**
   383  * \brief Copy a block of pixels of one format to another format
   384  *
   385  *  \return 0 on success, or -1 if there was an error
   386  */
   387 extern DECLSPEC int SDLCALL SDL_ConvertPixels(int width, int height,
   388                                               Uint32 src_format,
   389                                               const void * src, int src_pitch,
   390                                               Uint32 dst_format,
   391                                               void * dst, int dst_pitch);
   392 
   393 /**
   394  *  Performs a fast fill of the given rectangle with \c color.
   395  *
   396  *  If \c rect is NULL, the whole surface will be filled with \c color.
   397  *
   398  *  The color should be a pixel of the format used by the surface, and
   399  *  can be generated by the SDL_MapRGB() function.
   400  *
   401  *  \return 0 on success, or -1 on error.
   402  */
   403 extern DECLSPEC int SDLCALL SDL_FillRect
   404     (SDL_Surface * dst, const SDL_Rect * rect, Uint32 color);
   405 extern DECLSPEC int SDLCALL SDL_FillRects
   406     (SDL_Surface * dst, const SDL_Rect * rects, int count, Uint32 color);
   407 
   408 /**
   409  *  Performs a fast blit from the source surface to the destination surface.
   410  *
   411  *  This assumes that the source and destination rectangles are
   412  *  the same size.  If either \c srcrect or \c dstrect are NULL, the entire
   413  *  surface (\c src or \c dst) is copied.  The final blit rectangles are saved
   414  *  in \c srcrect and \c dstrect after all clipping is performed.
   415  *
   416  *  \return If the blit is successful, it returns 0, otherwise it returns -1.
   417  *
   418  *  The blit function should not be called on a locked surface.
   419  *
   420  *  The blit semantics for surfaces with and without blending and colorkey
   421  *  are defined as follows:
   422  *  \verbatim
   423     RGBA->RGB:
   424       Source surface blend mode set to SDL_BLENDMODE_BLEND:
   425         alpha-blend (using the source alpha-channel and per-surface alpha)
   426         SDL_SRCCOLORKEY ignored.
   427       Source surface blend mode set to SDL_BLENDMODE_NONE:
   428         copy RGB.
   429         if SDL_SRCCOLORKEY set, only copy the pixels matching the
   430         RGB values of the source color key, ignoring alpha in the
   431         comparison.
   432 
   433     RGB->RGBA:
   434       Source surface blend mode set to SDL_BLENDMODE_BLEND:
   435         alpha-blend (using the source per-surface alpha)
   436       Source surface blend mode set to SDL_BLENDMODE_NONE:
   437         copy RGB, set destination alpha to source per-surface alpha value.
   438       both:
   439         if SDL_SRCCOLORKEY set, only copy the pixels matching the
   440         source color key.
   441 
   442     RGBA->RGBA:
   443       Source surface blend mode set to SDL_BLENDMODE_BLEND:
   444         alpha-blend (using the source alpha-channel and per-surface alpha)
   445         SDL_SRCCOLORKEY ignored.
   446       Source surface blend mode set to SDL_BLENDMODE_NONE:
   447         copy all of RGBA to the destination.
   448         if SDL_SRCCOLORKEY set, only copy the pixels matching the
   449         RGB values of the source color key, ignoring alpha in the
   450         comparison.
   451 
   452     RGB->RGB:
   453       Source surface blend mode set to SDL_BLENDMODE_BLEND:
   454         alpha-blend (using the source per-surface alpha)
   455       Source surface blend mode set to SDL_BLENDMODE_NONE:
   456         copy RGB.
   457       both:
   458         if SDL_SRCCOLORKEY set, only copy the pixels matching the
   459         source color key.
   460     \endverbatim
   461  *
   462  *  You should call SDL_BlitSurface() unless you know exactly how SDL
   463  *  blitting works internally and how to use the other blit functions.
   464  */
   465 #define SDL_BlitSurface SDL_UpperBlit
   466 
   467 /**
   468  *  This is the public blit function, SDL_BlitSurface(), and it performs
   469  *  rectangle validation and clipping before passing it to SDL_LowerBlit()
   470  */
   471 extern DECLSPEC int SDLCALL SDL_UpperBlit
   472     (SDL_Surface * src, const SDL_Rect * srcrect,
   473      SDL_Surface * dst, SDL_Rect * dstrect);
   474 
   475 /**
   476  *  This is a semi-private blit function and it performs low-level surface
   477  *  blitting only.
   478  */
   479 extern DECLSPEC int SDLCALL SDL_LowerBlit
   480     (SDL_Surface * src, SDL_Rect * srcrect,
   481      SDL_Surface * dst, SDL_Rect * dstrect);
   482 
   483 /**
   484  *  \brief Perform a fast, low quality, stretch blit between two surfaces of the
   485  *         same pixel format.
   486  *
   487  *  \note This function uses a static buffer, and is not thread-safe.
   488  */
   489 extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src,
   490                                             const SDL_Rect * srcrect,
   491                                             SDL_Surface * dst,
   492                                             const SDL_Rect * dstrect);
   493 
   494 #define SDL_BlitScaled SDL_UpperBlitScaled
   495 
   496 /**
   497  *  This is the public scaled blit function, SDL_BlitScaled(), and it performs
   498  *  rectangle validation and clipping before passing it to SDL_LowerBlitScaled()
   499  */
   500 extern DECLSPEC int SDLCALL SDL_UpperBlitScaled
   501     (SDL_Surface * src, const SDL_Rect * srcrect,
   502     SDL_Surface * dst, SDL_Rect * dstrect);
   503 
   504 /**
   505  *  This is a semi-private blit function and it performs low-level surface
   506  *  scaled blitting only.
   507  */
   508 extern DECLSPEC int SDLCALL SDL_LowerBlitScaled
   509     (SDL_Surface * src, SDL_Rect * srcrect,
   510     SDL_Surface * dst, SDL_Rect * dstrect);
   511 
   512 
   513 /* Ends C function definitions when using C++ */
   514 #ifdef __cplusplus
   515 }
   516 #endif
   517 #include "close_code.h"
   518 
   519 #endif /* SDL_surface_h_ */
   520 
   521 /* vi: set ts=4 sw=4 expandtab: */