2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2009 Sam Lantinga
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.
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.
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
24 * Header file for access to the SDL raw framebuffer window
30 #include "SDL_stdinc.h"
31 #include "SDL_error.h"
32 #include "SDL_rwops.h"
34 #include "begin_code.h"
35 /* Set up for C function definitions, even when using C++ */
40 /** @name Transparency definitions
41 * These define alpha as the opacity of a surface
44 #define SDL_ALPHA_OPAQUE 255
45 #define SDL_ALPHA_TRANSPARENT 0
48 /** @name Useful data types */
50 typedef struct SDL_Rect {
55 typedef struct SDL_Color {
61 #define SDL_Colour SDL_Color
63 typedef struct SDL_Palette {
69 /** Everything in the pixel format structure is read-only */
70 typedef struct SDL_PixelFormat {
87 /** RGB color key information */
89 /** Alpha value information (per-surface alpha) */
93 /** This structure should be treated as read-only, except for 'pixels',
94 * which, if not NULL, contains the raw pixel data for the surface.
96 typedef struct SDL_Surface {
97 Uint32 flags; /**< Read-only */
98 SDL_PixelFormat *format; /**< Read-only */
99 int w, h; /**< Read-only */
100 Uint16 pitch; /**< Read-only */
101 void *pixels; /**< Read-write */
102 int offset; /**< Private */
104 /** Hardware-specific surface info */
105 struct private_hwdata *hwdata;
107 /** clipping information */
108 SDL_Rect clip_rect; /**< Read-only */
109 Uint32 unused1; /**< for binary compatibility */
111 /** Allow recursive locks */
112 Uint32 locked; /**< Private */
114 /** info for fast blit mapping to other surfaces */
115 struct SDL_BlitMap *map; /**< Private */
117 /** format version, bumped at every change to invalidate blit maps */
118 unsigned int format_version; /**< Private */
120 /** Reference count -- used when freeing surface */
121 int refcount; /**< Read-mostly */
124 /** @name SDL_Surface Flags
125 * These are the currently supported flags for the SDL_surface
129 /** Available for SDL_CreateRGBSurface() or SDL_SetVideoMode() */
131 #define SDL_SWSURFACE 0x00000000 /**< Surface is in system memory */
132 #define SDL_HWSURFACE 0x00000001 /**< Surface is in video memory */
133 #define SDL_ASYNCBLIT 0x00000004 /**< Use asynchronous blits if possible */
136 /** Available for SDL_SetVideoMode() */
138 #define SDL_ANYFORMAT 0x10000000 /**< Allow any video depth/pixel-format */
139 #define SDL_HWPALETTE 0x20000000 /**< Surface has exclusive palette */
140 #define SDL_DOUBLEBUF 0x40000000 /**< Set up double-buffered video mode */
141 #define SDL_FULLSCREEN 0x80000000 /**< Surface is a full screen display */
142 #define SDL_OPENGL 0x00000002 /**< Create an OpenGL rendering context */
143 #define SDL_OPENGLBLIT 0x0000000A /**< Create an OpenGL rendering context and use it for blitting */
144 #define SDL_RESIZABLE 0x00000010 /**< This video mode may be resized */
145 #define SDL_NOFRAME 0x00000020 /**< No window caption or edge frame */
148 /** Used internally (read-only) */
150 #define SDL_HWACCEL 0x00000100 /**< Blit uses hardware acceleration */
151 #define SDL_SRCCOLORKEY 0x00001000 /**< Blit uses a source color key */
152 #define SDL_RLEACCELOK 0x00002000 /**< Private flag */
153 #define SDL_RLEACCEL 0x00004000 /**< Surface is RLE encoded */
154 #define SDL_SRCALPHA 0x00010000 /**< Blit uses source alpha blending */
155 #define SDL_PREALLOC 0x01000000 /**< Surface uses preallocated memory */
160 /** Evaluates to true if the surface needs to be locked before access */
161 #define SDL_MUSTLOCK(surface) \
162 (surface->offset || \
163 ((surface->flags & (SDL_HWSURFACE|SDL_ASYNCBLIT|SDL_RLEACCEL)) != 0))
165 /** typedef for private surface blitting functions */
166 typedef int (*SDL_blit)(struct SDL_Surface *src, SDL_Rect *srcrect,
167 struct SDL_Surface *dst, SDL_Rect *dstrect);
170 /** Useful for determining the video hardware capabilities */
171 typedef struct SDL_VideoInfo {
172 Uint32 hw_available :1; /**< Flag: Can you create hardware surfaces? */
173 Uint32 wm_available :1; /**< Flag: Can you talk to a window manager? */
174 Uint32 UnusedBits1 :6;
175 Uint32 UnusedBits2 :1;
176 Uint32 blit_hw :1; /**< Flag: Accelerated blits HW --> HW */
177 Uint32 blit_hw_CC :1; /**< Flag: Accelerated blits with Colorkey */
178 Uint32 blit_hw_A :1; /**< Flag: Accelerated blits with Alpha */
179 Uint32 blit_sw :1; /**< Flag: Accelerated blits SW --> HW */
180 Uint32 blit_sw_CC :1; /**< Flag: Accelerated blits with Colorkey */
181 Uint32 blit_sw_A :1; /**< Flag: Accelerated blits with Alpha */
182 Uint32 blit_fill :1; /**< Flag: Accelerated color fill */
183 Uint32 UnusedBits3 :16;
184 Uint32 video_mem; /**< The total amount of video memory (in K) */
185 SDL_PixelFormat *vfmt; /**< Value: The format of the video surface */
186 int current_w; /**< Value: The current video mode width */
187 int current_h; /**< Value: The current video mode height */
191 /** @name Overlay Formats
192 * The most common video overlay formats.
193 * For an explanation of these pixel formats, see:
194 * http://www.webartz.com/fourcc/indexyuv.htm
196 * For information on the relationship between color spaces, see:
197 * http://www.neuro.sfc.keio.ac.jp/~aly/polygon/info/color-space-faq.html
200 #define SDL_YV12_OVERLAY 0x32315659 /**< Planar mode: Y + V + U (3 planes) */
201 #define SDL_IYUV_OVERLAY 0x56555949 /**< Planar mode: Y + U + V (3 planes) */
202 #define SDL_YUY2_OVERLAY 0x32595559 /**< Packed mode: Y0+U0+Y1+V0 (1 plane) */
203 #define SDL_UYVY_OVERLAY 0x59565955 /**< Packed mode: U0+Y0+V0+Y1 (1 plane) */
204 #define SDL_YVYU_OVERLAY 0x55595659 /**< Packed mode: Y0+V0+Y1+U0 (1 plane) */
207 /** The YUV hardware video overlay */
208 typedef struct SDL_Overlay {
209 Uint32 format; /**< Read-only */
210 int w, h; /**< Read-only */
211 int planes; /**< Read-only */
212 Uint16 *pitches; /**< Read-only */
213 Uint8 **pixels; /**< Read-write */
215 /** @name Hardware-specific surface info */
217 struct private_yuvhwfuncs *hwfuncs;
218 struct private_yuvhwdata *hwdata;
221 /** @name Special flags */
223 Uint32 hw_overlay :1; /**< Flag: This overlay hardware accelerated? */
224 Uint32 UnusedBits :31;
229 /** Public enumeration for setting the OpenGL window attributes. */
239 SDL_GL_ACCUM_RED_SIZE,
240 SDL_GL_ACCUM_GREEN_SIZE,
241 SDL_GL_ACCUM_BLUE_SIZE,
242 SDL_GL_ACCUM_ALPHA_SIZE,
244 SDL_GL_MULTISAMPLEBUFFERS,
245 SDL_GL_MULTISAMPLESAMPLES,
246 SDL_GL_ACCELERATED_VISUAL,
250 /** @name flags for SDL_SetPalette() */
252 #define SDL_LOGPAL 0x01
253 #define SDL_PHYSPAL 0x02
256 /* Function prototypes */
259 * @name Video Init and Quit
260 * These functions are used internally, and should not be used unless you
261 * have a specific need to specify the video driver you want to use.
262 * You should normally use SDL_Init() or SDL_InitSubSystem().
266 * Initializes the video subsystem. Sets up a connection
267 * to the window manager, etc, and determines the current video mode and
268 * pixel format, but does not initialize a window or graphics mode.
269 * Note that event handling is activated by this routine.
271 * If you use both sound and video in your application, you need to call
272 * SDL_Init() before opening the sound device, otherwise under Win32 DirectX,
273 * you won't be able to set full-screen display modes.
275 extern DECLSPEC int SDLCALL SDL_VideoInit(const char *driver_name, Uint32 flags);
276 extern DECLSPEC void SDLCALL SDL_VideoQuit(void);
280 * This function fills the given character buffer with the name of the
281 * video driver, and returns a pointer to it if the video driver has
282 * been initialized. It returns NULL if no driver has been initialized.
284 extern DECLSPEC char * SDLCALL SDL_VideoDriverName(char *namebuf, int maxlen);
287 * This function returns a pointer to the current display surface.
288 * If SDL is doing format conversion on the display surface, this
289 * function returns the publicly visible surface, not the real video
292 extern DECLSPEC SDL_Surface * SDLCALL SDL_GetVideoSurface(void);
295 * This function returns a read-only pointer to information about the
296 * video hardware. If this is called before SDL_SetVideoMode(), the 'vfmt'
297 * member of the returned structure will contain the pixel format of the
300 extern DECLSPEC const SDL_VideoInfo * SDLCALL SDL_GetVideoInfo(void);
303 * Check to see if a particular video mode is supported.
304 * It returns 0 if the requested mode is not supported under any bit depth,
305 * or returns the bits-per-pixel of the closest available mode with the
306 * given width and height. If this bits-per-pixel is different from the
307 * one used when setting the video mode, SDL_SetVideoMode() will succeed,
308 * but will emulate the requested bits-per-pixel with a shadow surface.
310 * The arguments to SDL_VideoModeOK() are the same ones you would pass to
313 extern DECLSPEC int SDLCALL SDL_VideoModeOK(int width, int height, int bpp, Uint32 flags);
316 * Return a pointer to an array of available screen dimensions for the
317 * given format and video flags, sorted largest to smallest. Returns
318 * NULL if there are no dimensions available for a particular format,
319 * or (SDL_Rect **)-1 if any dimension is okay for the given format.
321 * If 'format' is NULL, the mode list will be for the format given
322 * by SDL_GetVideoInfo()->vfmt
324 extern DECLSPEC SDL_Rect ** SDLCALL SDL_ListModes(SDL_PixelFormat *format, Uint32 flags);
327 * Set up a video mode with the specified width, height and bits-per-pixel.
329 * If 'bpp' is 0, it is treated as the current display bits per pixel.
331 * If SDL_ANYFORMAT is set in 'flags', the SDL library will try to set the
332 * requested bits-per-pixel, but will return whatever video pixel format is
333 * available. The default is to emulate the requested pixel format if it
334 * is not natively available.
336 * If SDL_HWSURFACE is set in 'flags', the video surface will be placed in
337 * video memory, if possible, and you may have to call SDL_LockSurface()
338 * in order to access the raw framebuffer. Otherwise, the video surface
339 * will be created in system memory.
341 * If SDL_ASYNCBLIT is set in 'flags', SDL will try to perform rectangle
342 * updates asynchronously, but you must always lock before accessing pixels.
343 * SDL will wait for updates to complete before returning from the lock.
345 * If SDL_HWPALETTE is set in 'flags', the SDL library will guarantee
346 * that the colors set by SDL_SetColors() will be the colors you get.
347 * Otherwise, in 8-bit mode, SDL_SetColors() may not be able to set all
348 * of the colors exactly the way they are requested, and you should look
349 * at the video surface structure to determine the actual palette.
350 * If SDL cannot guarantee that the colors you request can be set,
351 * i.e. if the colormap is shared, then the video surface may be created
352 * under emulation in system memory, overriding the SDL_HWSURFACE flag.
354 * If SDL_FULLSCREEN is set in 'flags', the SDL library will try to set
355 * a fullscreen video mode. The default is to create a windowed mode
356 * if the current graphics system has a window manager.
357 * If the SDL library is able to set a fullscreen video mode, this flag
358 * will be set in the surface that is returned.
360 * If SDL_DOUBLEBUF is set in 'flags', the SDL library will try to set up
361 * two surfaces in video memory and swap between them when you call
362 * SDL_Flip(). This is usually slower than the normal single-buffering
363 * scheme, but prevents "tearing" artifacts caused by modifying video
364 * memory while the monitor is refreshing. It should only be used by
365 * applications that redraw the entire screen on every update.
367 * If SDL_RESIZABLE is set in 'flags', the SDL library will allow the
368 * window manager, if any, to resize the window at runtime. When this
369 * occurs, SDL will send a SDL_VIDEORESIZE event to you application,
370 * and you must respond to the event by re-calling SDL_SetVideoMode()
371 * with the requested size (or another size that suits the application).
373 * If SDL_NOFRAME is set in 'flags', the SDL library will create a window
374 * without any title bar or frame decoration. Fullscreen video modes have
375 * this flag set automatically.
377 * This function returns the video framebuffer surface, or NULL if it fails.
379 * If you rely on functionality provided by certain video flags, check the
380 * flags of the returned surface to make sure that functionality is available.
381 * SDL will fall back to reduced functionality if the exact flags you wanted
384 extern DECLSPEC SDL_Surface * SDLCALL SDL_SetVideoMode
385 (int width, int height, int bpp, Uint32 flags);
387 /** @name SDL_Update Functions
388 * These functions should not be called while 'screen' is locked.
392 * Makes sure the given list of rectangles is updated on the given screen.
394 extern DECLSPEC void SDLCALL SDL_UpdateRects
395 (SDL_Surface *screen, int numrects, SDL_Rect *rects);
397 * If 'x', 'y', 'w' and 'h' are all 0, SDL_UpdateRect will update the entire
400 extern DECLSPEC void SDLCALL SDL_UpdateRect
401 (SDL_Surface *screen, Sint32 x, Sint32 y, Uint32 w, Uint32 h);
405 * On hardware that supports double-buffering, this function sets up a flip
406 * and returns. The hardware will wait for vertical retrace, and then swap
407 * video buffers before the next video surface blit or lock will return.
408 * On hardware that doesn not support double-buffering, this is equivalent
409 * to calling SDL_UpdateRect(screen, 0, 0, 0, 0);
410 * The SDL_DOUBLEBUF flag must have been passed to SDL_SetVideoMode() when
411 * setting the video mode for this function to perform hardware flipping.
412 * This function returns 0 if successful, or -1 if there was an error.
414 extern DECLSPEC int SDLCALL SDL_Flip(SDL_Surface *screen);
417 * Set the gamma correction for each of the color channels.
418 * The gamma values range (approximately) between 0.1 and 10.0
420 * If this function isn't supported directly by the hardware, it will
421 * be emulated using gamma ramps, if available. If successful, this
422 * function returns 0, otherwise it returns -1.
424 extern DECLSPEC int SDLCALL SDL_SetGamma(float red, float green, float blue);
427 * Set the gamma translation table for the red, green, and blue channels
428 * of the video hardware. Each table is an array of 256 16-bit quantities,
429 * representing a mapping between the input and output for that channel.
430 * The input is the index into the array, and the output is the 16-bit
431 * gamma value at that index, scaled to the output color precision.
433 * You may pass NULL for any of the channels to leave it unchanged.
434 * If the call succeeds, it will return 0. If the display driver or
435 * hardware does not support gamma translation, or otherwise fails,
436 * this function will return -1.
438 extern DECLSPEC int SDLCALL SDL_SetGammaRamp(const Uint16 *red, const Uint16 *green, const Uint16 *blue);
441 * Retrieve the current values of the gamma translation tables.
443 * You must pass in valid pointers to arrays of 256 16-bit quantities.
444 * Any of the pointers may be NULL to ignore that channel.
445 * If the call succeeds, it will return 0. If the display driver or
446 * hardware does not support gamma translation, or otherwise fails,
447 * this function will return -1.
449 extern DECLSPEC int SDLCALL SDL_GetGammaRamp(Uint16 *red, Uint16 *green, Uint16 *blue);
452 * Sets a portion of the colormap for the given 8-bit surface. If 'surface'
453 * is not a palettized surface, this function does nothing, returning 0.
454 * If all of the colors were set as passed to SDL_SetColors(), it will
455 * return 1. If not all the color entries were set exactly as given,
456 * it will return 0, and you should look at the surface palette to
457 * determine the actual color palette.
459 * When 'surface' is the surface associated with the current display, the
460 * display colormap will be updated with the requested colors. If
461 * SDL_HWPALETTE was set in SDL_SetVideoMode() flags, SDL_SetColors()
462 * will always return 1, and the palette is guaranteed to be set the way
463 * you desire, even if the window colormap has to be warped or run under
466 extern DECLSPEC int SDLCALL SDL_SetColors(SDL_Surface *surface,
467 SDL_Color *colors, int firstcolor, int ncolors);
470 * Sets a portion of the colormap for a given 8-bit surface.
471 * 'flags' is one or both of:
472 * SDL_LOGPAL -- set logical palette, which controls how blits are mapped
473 * to/from the surface,
474 * SDL_PHYSPAL -- set physical palette, which controls how pixels look on
476 * Only screens have physical palettes. Separate change of physical/logical
477 * palettes is only possible if the screen has SDL_HWPALETTE set.
479 * The return value is 1 if all colours could be set as requested, and 0
482 * SDL_SetColors() is equivalent to calling this function with
483 * flags = (SDL_LOGPAL|SDL_PHYSPAL).
485 extern DECLSPEC int SDLCALL SDL_SetPalette(SDL_Surface *surface, int flags,
486 SDL_Color *colors, int firstcolor,
490 * Maps an RGB triple to an opaque pixel value for a given pixel format
492 extern DECLSPEC Uint32 SDLCALL SDL_MapRGB
493 (const SDL_PixelFormat * const format,
494 const Uint8 r, const Uint8 g, const Uint8 b);
497 * Maps an RGBA quadruple to a pixel value for a given pixel format
499 extern DECLSPEC Uint32 SDLCALL SDL_MapRGBA
500 (const SDL_PixelFormat * const format,
501 const Uint8 r, const Uint8 g, const Uint8 b, const Uint8 a);
504 * Maps a pixel value into the RGB components for a given pixel format
506 extern DECLSPEC void SDLCALL SDL_GetRGB(Uint32 pixel,
507 const SDL_PixelFormat * const fmt,
508 Uint8 *r, Uint8 *g, Uint8 *b);
511 * Maps a pixel value into the RGBA components for a given pixel format
513 extern DECLSPEC void SDLCALL SDL_GetRGBA(Uint32 pixel,
514 const SDL_PixelFormat * const fmt,
515 Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a);
517 /** @sa SDL_CreateRGBSurface */
518 #define SDL_AllocSurface SDL_CreateRGBSurface
520 * Allocate and free an RGB surface (must be called after SDL_SetVideoMode)
521 * If the depth is 4 or 8 bits, an empty palette is allocated for the surface.
522 * If the depth is greater than 8 bits, the pixel format is set using the
524 * If the function runs out of memory, it will return NULL.
526 * The 'flags' tell what kind of surface to create.
527 * SDL_SWSURFACE means that the surface should be created in system memory.
528 * SDL_HWSURFACE means that the surface should be created in video memory,
529 * with the same format as the display surface. This is useful for surfaces
530 * that will not change much, to take advantage of hardware acceleration
531 * when being blitted to the display surface.
532 * SDL_ASYNCBLIT means that SDL will try to perform asynchronous blits with
533 * this surface, but you must always lock it before accessing the pixels.
534 * SDL will wait for current blits to finish before returning from the lock.
535 * SDL_SRCCOLORKEY indicates that the surface will be used for colorkey blits.
536 * If the hardware supports acceleration of colorkey blits between
537 * two surfaces in video memory, SDL will try to place the surface in
538 * video memory. If this isn't possible or if there is no hardware
539 * acceleration available, the surface will be placed in system memory.
540 * SDL_SRCALPHA means that the surface will be used for alpha blits and
541 * if the hardware supports hardware acceleration of alpha blits between
542 * two surfaces in video memory, to place the surface in video memory
543 * if possible, otherwise it will be placed in system memory.
544 * If the surface is created in video memory, blits will be _much_ faster,
545 * but the surface format must be identical to the video surface format,
546 * and the only way to access the pixels member of the surface is to use
547 * the SDL_LockSurface() and SDL_UnlockSurface() calls.
548 * If the requested surface actually resides in video memory, SDL_HWSURFACE
549 * will be set in the flags member of the returned surface. If for some
550 * reason the surface could not be placed in video memory, it will not have
551 * the SDL_HWSURFACE flag set, and will be created in system memory instead.
553 extern DECLSPEC SDL_Surface * SDLCALL SDL_CreateRGBSurface
554 (Uint32 flags, int width, int height, int depth,
555 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
556 /** @sa SDL_CreateRGBSurface */
557 extern DECLSPEC SDL_Surface * SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels,
558 int width, int height, int depth, int pitch,
559 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
560 extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface *surface);
563 * SDL_LockSurface() sets up a surface for directly accessing the pixels.
564 * Between calls to SDL_LockSurface()/SDL_UnlockSurface(), you can write
565 * to and read from 'surface->pixels', using the pixel format stored in
566 * 'surface->format'. Once you are done accessing the surface, you should
567 * use SDL_UnlockSurface() to release it.
569 * Not all surfaces require locking. If SDL_MUSTLOCK(surface) evaluates
570 * to 0, then you can read and write to the surface at any time, and the
571 * pixel format of the surface will not change. In particular, if the
572 * SDL_HWSURFACE flag is not given when calling SDL_SetVideoMode(), you
573 * will not need to lock the display surface before accessing it.
575 * No operating system or library calls should be made between lock/unlock
576 * pairs, as critical system locks may be held during this time.
578 * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked.
580 extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface *surface);
581 extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface *surface);
584 * Load a surface from a seekable SDL data source (memory or file.)
585 * If 'freesrc' is non-zero, the source will be closed after being read.
586 * Returns the new surface, or NULL if there was an error.
587 * The new surface should be freed with SDL_FreeSurface().
589 extern DECLSPEC SDL_Surface * SDLCALL SDL_LoadBMP_RW(SDL_RWops *src, int freesrc);
591 /** Convenience macro -- load a surface from a file */
592 #define SDL_LoadBMP(file) SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1)
595 * Save a surface to a seekable SDL data source (memory or file.)
596 * If 'freedst' is non-zero, the source will be closed after being written.
597 * Returns 0 if successful or -1 if there was an error.
599 extern DECLSPEC int SDLCALL SDL_SaveBMP_RW
600 (SDL_Surface *surface, SDL_RWops *dst, int freedst);
602 /** Convenience macro -- save a surface to a file */
603 #define SDL_SaveBMP(surface, file) \
604 SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1)
607 * Sets the color key (transparent pixel) in a blittable surface.
608 * If 'flag' is SDL_SRCCOLORKEY (optionally OR'd with SDL_RLEACCEL),
609 * 'key' will be the transparent pixel in the source image of a blit.
610 * SDL_RLEACCEL requests RLE acceleration for the surface if present,
611 * and removes RLE acceleration if absent.
612 * If 'flag' is 0, this function clears any current color key.
613 * This function returns 0, or -1 if there was an error.
615 extern DECLSPEC int SDLCALL SDL_SetColorKey
616 (SDL_Surface *surface, Uint32 flag, Uint32 key);
619 * This function sets the alpha value for the entire surface, as opposed to
620 * using the alpha component of each pixel. This value measures the range
621 * of transparency of the surface, 0 being completely transparent to 255
622 * being completely opaque. An 'alpha' value of 255 causes blits to be
623 * opaque, the source pixels copied to the destination (the default). Note
624 * that per-surface alpha can be combined with colorkey transparency.
626 * If 'flag' is 0, alpha blending is disabled for the surface.
627 * If 'flag' is SDL_SRCALPHA, alpha blending is enabled for the surface.
628 * OR:ing the flag with SDL_RLEACCEL requests RLE acceleration for the
629 * surface; if SDL_RLEACCEL is not specified, the RLE accel will be removed.
631 * The 'alpha' parameter is ignored for surfaces that have an alpha channel.
633 extern DECLSPEC int SDLCALL SDL_SetAlpha(SDL_Surface *surface, Uint32 flag, Uint8 alpha);
636 * Sets the clipping rectangle for the destination surface in a blit.
638 * If the clip rectangle is NULL, clipping will be disabled.
639 * If the clip rectangle doesn't intersect the surface, the function will
640 * return SDL_FALSE and blits will be completely clipped. Otherwise the
641 * function returns SDL_TRUE and blits to the surface will be clipped to
642 * the intersection of the surface area and the clipping rectangle.
644 * Note that blits are automatically clipped to the edges of the source
645 * and destination surfaces.
647 extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface *surface, const SDL_Rect *rect);
650 * Gets the clipping rectangle for the destination surface in a blit.
651 * 'rect' must be a pointer to a valid rectangle which will be filled
652 * with the correct values.
654 extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface *surface, SDL_Rect *rect);
657 * Creates a new surface of the specified format, and then copies and maps
658 * the given surface to it so the blit of the converted surface will be as
659 * fast as possible. If this function fails, it returns NULL.
661 * The 'flags' parameter is passed to SDL_CreateRGBSurface() and has those
662 * semantics. You can also pass SDL_RLEACCEL in the flags parameter and
663 * SDL will try to RLE accelerate colorkey and alpha blits in the resulting
666 * This function is used internally by SDL_DisplayFormat().
668 extern DECLSPEC SDL_Surface * SDLCALL SDL_ConvertSurface
669 (SDL_Surface *src, SDL_PixelFormat *fmt, Uint32 flags);
672 * This performs a fast blit from the source surface to the destination
673 * surface. It assumes that the source and destination rectangles are
674 * the same size. If either 'srcrect' or 'dstrect' are NULL, the entire
675 * surface (src or dst) is copied. The final blit rectangles are saved
676 * in 'srcrect' and 'dstrect' after all clipping is performed.
677 * If the blit is successful, it returns 0, otherwise it returns -1.
679 * The blit function should not be called on a locked surface.
681 * The blit semantics for surfaces with and without alpha and colorkey
682 * are defined as follows:
686 * alpha-blend (using alpha-channel).
687 * SDL_SRCCOLORKEY ignored.
688 * SDL_SRCALPHA not set:
690 * if SDL_SRCCOLORKEY set, only copy the pixels matching the
691 * RGB values of the source colour key, ignoring alpha in the
696 * alpha-blend (using the source per-surface alpha value);
697 * set destination alpha to opaque.
698 * SDL_SRCALPHA not set:
699 * copy RGB, set destination alpha to source per-surface alpha value.
701 * if SDL_SRCCOLORKEY set, only copy the pixels matching the
706 * alpha-blend (using the source alpha channel) the RGB values;
707 * leave destination alpha untouched. [Note: is this correct?]
708 * SDL_SRCCOLORKEY ignored.
709 * SDL_SRCALPHA not set:
710 * copy all of RGBA to the destination.
711 * if SDL_SRCCOLORKEY set, only copy the pixels matching the
712 * RGB values of the source colour key, ignoring alpha in the
717 * alpha-blend (using the source per-surface alpha value).
718 * SDL_SRCALPHA not set:
721 * if SDL_SRCCOLORKEY set, only copy the pixels matching the
724 * If either of the surfaces were in video memory, and the blit returns -2,
725 * the video memory was lost, so it should be reloaded with artwork and
728 * while ( SDL_BlitSurface(image, imgrect, screen, dstrect) == -2 ) {
729 * while ( SDL_LockSurface(image) < 0 )
731 * -- Write image pixels to image->pixels --
732 * SDL_UnlockSurface(image);
736 * This happens under DirectX 5.0 when the system switches away from your
737 * fullscreen application. The lock will also fail until you have access
738 * to the video memory again.
740 * You should call SDL_BlitSurface() unless you know exactly how SDL
741 * blitting works internally and how to use the other blit functions.
743 #define SDL_BlitSurface SDL_UpperBlit
745 /** This is the public blit function, SDL_BlitSurface(), and it performs
746 * rectangle validation and clipping before passing it to SDL_LowerBlit()
748 extern DECLSPEC int SDLCALL SDL_UpperBlit
749 (SDL_Surface *src, SDL_Rect *srcrect,
750 SDL_Surface *dst, SDL_Rect *dstrect);
751 /** This is a semi-private blit function and it performs low-level surface
754 extern DECLSPEC int SDLCALL SDL_LowerBlit
755 (SDL_Surface *src, SDL_Rect *srcrect,
756 SDL_Surface *dst, SDL_Rect *dstrect);
759 * This function performs a fast fill of the given rectangle with 'color'
760 * The given rectangle is clipped to the destination surface clip area
761 * and the final fill rectangle is saved in the passed in pointer.
762 * If 'dstrect' is NULL, the whole surface will be filled with 'color'
763 * The color should be a pixel of the format used by the surface, and
764 * can be generated by the SDL_MapRGB() function.
765 * This function returns 0 on success, or -1 on error.
767 extern DECLSPEC int SDLCALL SDL_FillRect
768 (SDL_Surface *dst, SDL_Rect *dstrect, Uint32 color);
771 * This function takes a surface and copies it to a new surface of the
772 * pixel format and colors of the video framebuffer, suitable for fast
773 * blitting onto the display surface. It calls SDL_ConvertSurface()
775 * If you want to take advantage of hardware colorkey or alpha blit
776 * acceleration, you should set the colorkey and alpha value before
777 * calling this function.
779 * If the conversion fails or runs out of memory, it returns NULL
781 extern DECLSPEC SDL_Surface * SDLCALL SDL_DisplayFormat(SDL_Surface *surface);
784 * This function takes a surface and copies it to a new surface of the
785 * pixel format and colors of the video framebuffer (if possible),
786 * suitable for fast alpha blitting onto the display surface.
787 * The new surface will always have an alpha channel.
789 * If you want to take advantage of hardware colorkey or alpha blit
790 * acceleration, you should set the colorkey and alpha value before
791 * calling this function.
793 * If the conversion fails or runs out of memory, it returns NULL
795 extern DECLSPEC SDL_Surface * SDLCALL SDL_DisplayFormatAlpha(SDL_Surface *surface);
798 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
799 /** @name YUV video surface overlay functions */ /*@{*/
800 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
802 /** This function creates a video output overlay
803 * Calling the returned surface an overlay is something of a misnomer because
804 * the contents of the display surface underneath the area where the overlay
805 * is shown is undefined - it may be overwritten with the converted YUV data.
807 extern DECLSPEC SDL_Overlay * SDLCALL SDL_CreateYUVOverlay(int width, int height,
808 Uint32 format, SDL_Surface *display);
810 /** Lock an overlay for direct access, and unlock it when you are done */
811 extern DECLSPEC int SDLCALL SDL_LockYUVOverlay(SDL_Overlay *overlay);
812 extern DECLSPEC void SDLCALL SDL_UnlockYUVOverlay(SDL_Overlay *overlay);
814 /** Blit a video overlay to the display surface.
815 * The contents of the video surface underneath the blit destination are
817 * The width and height of the destination rectangle may be different from
818 * that of the overlay, but currently only 2x scaling is supported.
820 extern DECLSPEC int SDLCALL SDL_DisplayYUVOverlay(SDL_Overlay *overlay, SDL_Rect *dstrect);
822 /** Free a video overlay */
823 extern DECLSPEC void SDLCALL SDL_FreeYUVOverlay(SDL_Overlay *overlay);
827 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
828 /** @name OpenGL support functions. */ /*@{*/
829 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
832 * Dynamically load an OpenGL library, or the default one if path is NULL
834 * If you do this, you need to retrieve all of the GL functions used in
835 * your program from the dynamic library using SDL_GL_GetProcAddress().
837 extern DECLSPEC int SDLCALL SDL_GL_LoadLibrary(const char *path);
840 * Get the address of a GL function
842 extern DECLSPEC void * SDLCALL SDL_GL_GetProcAddress(const char* proc);
845 * Set an attribute of the OpenGL subsystem before intialization.
847 extern DECLSPEC int SDLCALL SDL_GL_SetAttribute(SDL_GLattr attr, int value);
850 * Get an attribute of the OpenGL subsystem from the windowing
851 * interface, such as glX. This is of course different from getting
852 * the values from SDL's internal OpenGL subsystem, which only
853 * stores the values you request before initialization.
855 * Developers should track the values they pass into SDL_GL_SetAttribute
856 * themselves if they want to retrieve these values.
858 extern DECLSPEC int SDLCALL SDL_GL_GetAttribute(SDL_GLattr attr, int* value);
861 * Swap the OpenGL buffers, if double-buffering is supported.
863 extern DECLSPEC void SDLCALL SDL_GL_SwapBuffers(void);
865 /** @name OpenGL Internal Functions
866 * Internal functions that should not be called unless you have read
867 * and understood the source code for these functions.
870 extern DECLSPEC void SDLCALL SDL_GL_UpdateRects(int numrects, SDL_Rect* rects);
871 extern DECLSPEC void SDLCALL SDL_GL_Lock(void);
872 extern DECLSPEC void SDLCALL SDL_GL_Unlock(void);
877 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
878 /** @name Window Manager Functions */
879 /** These functions allow interaction with the window manager, if any. */ /*@{*/
880 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
883 * Sets the title and icon text of the display window (UTF-8 encoded)
885 extern DECLSPEC void SDLCALL SDL_WM_SetCaption(const char *title, const char *icon);
887 * Gets the title and icon text of the display window (UTF-8 encoded)
889 extern DECLSPEC void SDLCALL SDL_WM_GetCaption(char **title, char **icon);
892 * Sets the icon for the display window.
893 * This function must be called before the first call to SDL_SetVideoMode().
894 * It takes an icon surface, and a mask in MSB format.
895 * If 'mask' is NULL, the entire icon surface will be used as the icon.
897 extern DECLSPEC void SDLCALL SDL_WM_SetIcon(SDL_Surface *icon, Uint8 *mask);
900 * This function iconifies the window, and returns 1 if it succeeded.
901 * If the function succeeds, it generates an SDL_APPACTIVE loss event.
902 * This function is a noop and returns 0 in non-windowed environments.
904 extern DECLSPEC int SDLCALL SDL_WM_IconifyWindow(void);
907 * Toggle fullscreen mode without changing the contents of the screen.
908 * If the display surface does not require locking before accessing
909 * the pixel information, then the memory pointers will not change.
911 * If this function was able to toggle fullscreen mode (change from
912 * running in a window to fullscreen, or vice-versa), it will return 1.
913 * If it is not implemented, or fails, it returns 0.
915 * The next call to SDL_SetVideoMode() will set the mode fullscreen
916 * attribute based on the flags parameter - if SDL_FULLSCREEN is not
917 * set, then the display will be windowed by default where supported.
919 * This is currently only implemented in the X11 video driver.
921 extern DECLSPEC int SDLCALL SDL_WM_ToggleFullScreen(SDL_Surface *surface);
927 SDL_GRAB_FULLSCREEN /**< Used internally */
930 * This function allows you to set and query the input grab state of
931 * the application. It returns the new input grab state.
933 * Grabbing means that the mouse is confined to the application window,
934 * and nearly all keyboard input is passed directly to the application,
935 * and not interpreted by a window manager, if any.
937 extern DECLSPEC SDL_GrabMode SDLCALL SDL_WM_GrabInput(SDL_GrabMode mode);
941 /** @internal Not in public API at the moment - do not use! */
942 extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface *src, SDL_Rect *srcrect,
943 SDL_Surface *dst, SDL_Rect *dstrect);
945 /* Ends C function definitions when using C++ */
949 #include "close_code.h"
951 #endif /* _SDL_video_h */