SDL_surface.h 41 KB

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  1. /*
  2. Simple DirectMedia Layer
  3. Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
  4. This software is provided 'as-is', without any express or implied
  5. warranty. In no event will the authors be held liable for any damages
  6. arising from the use of this software.
  7. Permission is granted to anyone to use this software for any purpose,
  8. including commercial applications, and to alter it and redistribute it
  9. freely, subject to the following restrictions:
  10. 1. The origin of this software must not be misrepresented; you must not
  11. claim that you wrote the original software. If you use this software
  12. in a product, an acknowledgment in the product documentation would be
  13. appreciated but is not required.
  14. 2. Altered source versions must be plainly marked as such, and must not be
  15. misrepresented as being the original software.
  16. 3. This notice may not be removed or altered from any source distribution.
  17. */
  18. /**
  19. * \file SDL_surface.h
  20. *
  21. * Header file for ::SDL_Surface definition and management functions.
  22. */
  23. #ifndef SDL_surface_h_
  24. #define SDL_surface_h_
  25. #include <SDL3/SDL_stdinc.h>
  26. #include <SDL3/SDL_blendmode.h>
  27. #include <SDL3/SDL_pixels.h>
  28. #include <SDL3/SDL_properties.h>
  29. #include <SDL3/SDL_rect.h>
  30. #include <SDL3/SDL_rwops.h>
  31. #include <SDL3/SDL_begin_code.h>
  32. /* Set up for C function definitions, even when using C++ */
  33. #ifdef __cplusplus
  34. extern "C" {
  35. #endif
  36. /**
  37. * \name Surface flags
  38. *
  39. * These are the currently supported flags for the ::SDL_Surface.
  40. *
  41. * \internal
  42. * Used internally (read-only).
  43. */
  44. /* @{ */
  45. #define SDL_SWSURFACE 0 /**< Just here for compatibility */
  46. #define SDL_PREALLOC 0x00000001 /**< Surface uses preallocated memory */
  47. #define SDL_RLEACCEL 0x00000002 /**< Surface is RLE encoded */
  48. #define SDL_DONTFREE 0x00000004 /**< Surface is referenced internally */
  49. #define SDL_SIMD_ALIGNED 0x00000008 /**< Surface uses aligned memory */
  50. #define SDL_SURFACE_USES_PROPERTIES 0x00000010 /**< Surface uses properties */
  51. /* @} *//* Surface flags */
  52. /**
  53. * Evaluates to true if the surface needs to be locked before access.
  54. */
  55. #define SDL_MUSTLOCK(S) (((S)->flags & SDL_RLEACCEL) != 0)
  56. typedef struct SDL_BlitMap SDL_BlitMap; /* this is an opaque type. */
  57. /**
  58. * The scaling mode
  59. */
  60. typedef enum
  61. {
  62. SDL_SCALEMODE_NEAREST, /**< nearest pixel sampling */
  63. SDL_SCALEMODE_LINEAR, /**< linear filtering */
  64. SDL_SCALEMODE_BEST /**< anisotropic filtering */
  65. } SDL_ScaleMode;
  66. /**
  67. * The flip mode
  68. */
  69. typedef enum
  70. {
  71. SDL_FLIP_NONE, /**< Do not flip */
  72. SDL_FLIP_HORIZONTAL, /**< flip horizontally */
  73. SDL_FLIP_VERTICAL /**< flip vertically */
  74. } SDL_FlipMode;
  75. /**
  76. * A collection of pixels used in software blitting.
  77. *
  78. * Pixels are arranged in memory in rows, with the top row first.
  79. * Each row occupies an amount of memory given by the pitch (sometimes
  80. * known as the row stride in non-SDL APIs).
  81. *
  82. * Within each row, pixels are arranged from left to right until the
  83. * width is reached.
  84. * Each pixel occupies a number of bits appropriate for its format, with
  85. * most formats representing each pixel as one or more whole bytes
  86. * (in some indexed formats, instead multiple pixels are packed into
  87. * each byte), and a byte order given by the format.
  88. * After encoding all pixels, any remaining bytes to reach the pitch are
  89. * used as padding to reach a desired alignment, and have undefined contents.
  90. *
  91. * \note This structure should be treated as read-only, except for \c pixels,
  92. * which, if not NULL, contains the raw pixel data for the surface.
  93. * \sa SDL_CreateSurfaceFrom
  94. */
  95. typedef struct SDL_Surface
  96. {
  97. Uint32 flags; /**< Read-only */
  98. SDL_PixelFormat *format; /**< Read-only */
  99. int w, h; /**< Read-only */
  100. int pitch; /**< Read-only */
  101. void *pixels; /**< Read-write */
  102. void *reserved; /**< Private */
  103. /** information needed for surfaces requiring locks */
  104. int locked; /**< Read-only */
  105. /** list of BlitMap that hold a reference to this surface */
  106. void *list_blitmap; /**< Private */
  107. /** clipping information */
  108. SDL_Rect clip_rect; /**< Read-only */
  109. /** info for fast blit mapping to other surfaces */
  110. SDL_BlitMap *map; /**< Private */
  111. /** Reference count -- used when freeing surface */
  112. int refcount; /**< Read-mostly */
  113. } SDL_Surface;
  114. /**
  115. * The type of function used for surface blitting functions.
  116. */
  117. typedef int (SDLCALL *SDL_blit) (struct SDL_Surface *src, const SDL_Rect *srcrect,
  118. struct SDL_Surface *dst, const SDL_Rect *dstrect);
  119. /**
  120. * Allocate a new RGB surface with a specific pixel format.
  121. *
  122. * \param width the width of the surface
  123. * \param height the height of the surface
  124. * \param format the SDL_PixelFormatEnum for the new surface's pixel format.
  125. * \returns the new SDL_Surface structure that is created or NULL if it fails;
  126. * call SDL_GetError() for more information.
  127. *
  128. * \since This function is available since SDL 3.0.0.
  129. *
  130. * \sa SDL_CreateSurfaceFrom
  131. * \sa SDL_DestroySurface
  132. */
  133. extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateSurface
  134. (int width, int height, Uint32 format);
  135. /**
  136. * Allocate a new RGB surface with a specific pixel format and existing pixel
  137. * data.
  138. *
  139. * No copy is made of the pixel data. Pixel data is not managed automatically;
  140. * you must free the surface before you free the pixel data.
  141. *
  142. * Pitch is the offset in bytes from one row of pixels to the next, e.g.
  143. * `width*4` for `SDL_PIXELFORMAT_RGBA8888`.
  144. *
  145. * You may pass NULL for pixels and 0 for pitch to create a surface that you
  146. * will fill in with valid values later.
  147. *
  148. * \param pixels a pointer to existing pixel data
  149. * \param width the width of the surface
  150. * \param height the height of the surface
  151. * \param pitch the pitch of the surface in bytes
  152. * \param format the SDL_PixelFormatEnum for the new surface's pixel format.
  153. * \returns the new SDL_Surface structure that is created or NULL if it fails;
  154. * call SDL_GetError() for more information.
  155. *
  156. * \since This function is available since SDL 3.0.0.
  157. *
  158. * \sa SDL_CreateSurface
  159. * \sa SDL_DestroySurface
  160. */
  161. extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateSurfaceFrom
  162. (void *pixels, int width, int height, int pitch, Uint32 format);
  163. /**
  164. * Free an RGB surface.
  165. *
  166. * It is safe to pass NULL to this function.
  167. *
  168. * \param surface the SDL_Surface to free.
  169. *
  170. * \since This function is available since SDL 3.0.0.
  171. *
  172. * \sa SDL_CreateSurface
  173. * \sa SDL_CreateSurfaceFrom
  174. * \sa SDL_LoadBMP
  175. * \sa SDL_LoadBMP_RW
  176. */
  177. extern DECLSPEC void SDLCALL SDL_DestroySurface(SDL_Surface *surface);
  178. /**
  179. * Get the properties associated with a surface.
  180. *
  181. * The following properties are understood by SDL:
  182. *
  183. * - `SDL_PROP_SURFACE_COLORSPACE_NUMBER`: an SDL_ColorSpace value describing
  184. * the surface colorspace, defaults to SDL_COLORSPACE_SRGB_LINEAR for
  185. * floating point formats, SDL_COLORSPACE_HDR10 for 10-bit formats,
  186. * SDL_COLORSPACE_SRGB for other RGB surfaces and SDL_COLORSPACE_BT709_FULL
  187. * for YUV surfaces.
  188. * - `SDL_PROP_SURFACE_MAXCLL_NUMBER`: MaxCLL (Maximum Content Light Level)
  189. * indicates the maximum light level of any single pixel (in cd/m2 or nits)
  190. * of the content. MaxCLL is usually measured off the final delivered
  191. * content after mastering. If one uses the full light level of the HDR
  192. * mastering display and adds a hard clip at its maximum value, MaxCLL would
  193. * be equal to the peak luminance of the mastering monitor. This defaults to
  194. * 400 for HDR10 surfaces.
  195. * - `SDL_PROP_SURFACE_MAXFALL_NUMBER`: MaxFALL (Maximum Frame Average Light
  196. * Level) indicates the maximum value of the frame average light level (in
  197. * cd/m2 or nits) of the content. MaxFALL is calculated by averaging the
  198. * decoded luminance values of all the pixels within a frame. MaxFALL is
  199. * usually much lower than MaxCLL.
  200. * - `SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT`: for HDR10 and floating point
  201. * surfaces, this defines the value of 100% diffuse white, with higher
  202. * values being displayed in the High Dynamic Range headroom. This defaults
  203. * to 100 for HDR10 surfaces and 1.0 for other surfaces.
  204. * - `SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT`: for HDR10 and floating point
  205. * surfaces, this defines the maximum dynamic range used by the content, in
  206. * terms of the SDR white point. This defaults to
  207. * SDL_PROP_SURFACE_MAXCLL_NUMBER / SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT,
  208. * or 4.0, for HDR10 surfaces.
  209. * - `SDL_PROP_SURFACE_TONEMAP_OPERATOR_STRING`: the tone mapping operator
  210. * used when compressing from a surface with high dynamic range to another
  211. * with lower dynamic range. Currently this supports "chrome", which uses
  212. * the same tone mapping that Chrome uses for HDR content, the form "*=N",
  213. * where N is a floating point scale factor applied in linear space, and
  214. * "none", which disables tone mapping. This defaults to "chrome".
  215. *
  216. * \param surface the SDL_Surface structure to query
  217. * \returns a valid property ID on success or 0 on failure; call
  218. * SDL_GetError() for more information.
  219. *
  220. * \since This function is available since SDL 3.0.0.
  221. *
  222. * \sa SDL_GetProperty
  223. * \sa SDL_SetProperty
  224. */
  225. extern DECLSPEC SDL_PropertiesID SDLCALL SDL_GetSurfaceProperties(SDL_Surface *surface);
  226. #define SDL_PROP_SURFACE_COLORSPACE_NUMBER "SDL.surface.colorspace"
  227. #define SDL_PROP_SURFACE_MAXCLL_NUMBER "SDL.surface.maxCLL"
  228. #define SDL_PROP_SURFACE_MAXFALL_NUMBER "SDL.surface.maxFALL"
  229. #define SDL_PROP_SURFACE_SDR_WHITE_POINT_FLOAT "SDL.surface.SDR_white_point"
  230. #define SDL_PROP_SURFACE_HDR_HEADROOM_FLOAT "SDL.surface.HDR_headroom"
  231. #define SDL_PROP_SURFACE_TONEMAP_OPERATOR_STRING "SDL.surface.tonemap"
  232. /**
  233. * Set the colorspace used by a surface.
  234. *
  235. * Setting the colorspace doesn't change the pixels, only how they are
  236. * interpreted in color operations.
  237. *
  238. * \param surface the SDL_Surface structure to update
  239. * \param colorspace an SDL_ColorSpace value describing the surface colorspace
  240. * \returns 0 on success or a negative error code on failure; call
  241. * SDL_GetError() for more information.
  242. *
  243. * \since This function is available since SDL 3.0.0.
  244. */
  245. extern DECLSPEC int SDLCALL SDL_SetSurfaceColorspace(SDL_Surface *surface, SDL_Colorspace colorspace);
  246. /**
  247. * Get the colorspace used by a surface.
  248. *
  249. * The colorspace defaults to SDL_COLORSPACE_SRGB_LINEAR for floating point
  250. * formats, SDL_COLORSPACE_HDR10 for 10-bit formats, SDL_COLORSPACE_SRGB for
  251. * other RGB surfaces and SDL_COLORSPACE_BT709_FULL for YUV textures.
  252. *
  253. * \param surface the SDL_Surface structure to query
  254. * \param colorspace a pointer filled in with an SDL_ColorSpace value
  255. * describing the surface colorspace
  256. * \returns 0 on success or a negative error code on failure; call
  257. * SDL_GetError() for more information.
  258. *
  259. * \since This function is available since SDL 3.0.0.
  260. */
  261. extern DECLSPEC int SDLCALL SDL_GetSurfaceColorspace(SDL_Surface *surface, SDL_Colorspace *colorspace);
  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. * \since This function is available since SDL 3.0.0.
  273. */
  274. extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface *surface, SDL_Palette *palette);
  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. * \since This function is available since SDL 3.0.0.
  292. *
  293. * \sa SDL_MUSTLOCK
  294. * \sa SDL_UnlockSurface
  295. */
  296. extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface *surface);
  297. /**
  298. * Release a surface after directly accessing the pixels.
  299. *
  300. * \param surface the SDL_Surface structure to be unlocked
  301. *
  302. * \since This function is available since SDL 3.0.0.
  303. *
  304. * \sa SDL_LockSurface
  305. */
  306. extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface *surface);
  307. /**
  308. * Load a BMP image from a seekable SDL data stream.
  309. *
  310. * The new surface should be freed with SDL_DestroySurface(). Not doing so
  311. * will result in a memory leak.
  312. *
  313. * \param src the data stream for the surface
  314. * \param freesrc if SDL_TRUE, calls SDL_RWclose() on `src` before returning,
  315. * even in the case of an error
  316. * \returns a pointer to a new SDL_Surface structure or NULL if there was an
  317. * error; call SDL_GetError() for more information.
  318. *
  319. * \since This function is available since SDL 3.0.0.
  320. *
  321. * \sa SDL_DestroySurface
  322. * \sa SDL_LoadBMP
  323. * \sa SDL_SaveBMP_RW
  324. */
  325. extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops *src, SDL_bool freesrc);
  326. /**
  327. * Load a BMP image from a file.
  328. *
  329. * The new surface should be freed with SDL_DestroySurface(). Not doing so
  330. * will result in a memory leak.
  331. *
  332. * \param file the BMP file to load
  333. * \returns a pointer to a new SDL_Surface structure or NULL if there was an
  334. * error; call SDL_GetError() for more information.
  335. *
  336. * \since This function is available since SDL 3.0.0.
  337. *
  338. * \sa SDL_DestroySurface
  339. * \sa SDL_LoadBMP_RW
  340. * \sa SDL_SaveBMP
  341. */
  342. extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP(const char *file);
  343. /**
  344. * Save a surface to a seekable SDL data stream in BMP format.
  345. *
  346. * Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the
  347. * BMP directly. Other RGB formats with 8-bit or higher get converted to a
  348. * 24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit
  349. * surface before they are saved. YUV and paletted 1-bit and 4-bit formats are
  350. * not supported.
  351. *
  352. * \param surface the SDL_Surface structure containing the image to be saved
  353. * \param dst a data stream to save to
  354. * \param freedst if SDL_TRUE, calls SDL_RWclose() on `dst` before returning,
  355. * even in the case of an error
  356. * \returns 0 on success or a negative error code on failure; call
  357. * SDL_GetError() for more information.
  358. *
  359. * \since This function is available since SDL 3.0.0.
  360. *
  361. * \sa SDL_LoadBMP_RW
  362. * \sa SDL_SaveBMP
  363. */
  364. extern DECLSPEC int SDLCALL SDL_SaveBMP_RW(SDL_Surface *surface, SDL_RWops *dst, SDL_bool freedst);
  365. /**
  366. * Save a surface to a file.
  367. *
  368. * Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the
  369. * BMP directly. Other RGB formats with 8-bit or higher get converted to a
  370. * 24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit
  371. * surface before they are saved. YUV and paletted 1-bit and 4-bit formats are
  372. * not supported.
  373. *
  374. * \param surface the SDL_Surface structure containing the image to be saved
  375. * \param file a file to save to
  376. * \returns 0 on success or a negative error code on failure; call
  377. * SDL_GetError() for more information.
  378. *
  379. * \since This function is available since SDL 3.0.0.
  380. *
  381. * \sa SDL_LoadBMP
  382. * \sa SDL_SaveBMP_RW
  383. */
  384. extern DECLSPEC int SDLCALL SDL_SaveBMP(SDL_Surface *surface, const char *file);
  385. /**
  386. * Set the RLE acceleration hint for a surface.
  387. *
  388. * If RLE is enabled, color key and alpha blending blits are much faster, but
  389. * the surface must be locked before directly accessing the pixels.
  390. *
  391. * \param surface the SDL_Surface structure to optimize
  392. * \param flag 0 to disable, non-zero to enable RLE acceleration
  393. * \returns 0 on success or a negative error code on failure; call
  394. * SDL_GetError() for more information.
  395. *
  396. * \since This function is available since SDL 3.0.0.
  397. *
  398. * \sa SDL_BlitSurface
  399. * \sa SDL_LockSurface
  400. * \sa SDL_UnlockSurface
  401. */
  402. extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface *surface, int flag);
  403. /**
  404. * Returns whether the surface is RLE enabled
  405. *
  406. * It is safe to pass a NULL `surface` here; it will return SDL_FALSE.
  407. *
  408. * \param surface the SDL_Surface structure to query
  409. * \returns SDL_TRUE if the surface is RLE enabled, SDL_FALSE otherwise.
  410. *
  411. * \since This function is available since SDL 3.0.0.
  412. *
  413. * \sa SDL_SetSurfaceRLE
  414. */
  415. extern DECLSPEC SDL_bool SDLCALL SDL_SurfaceHasRLE(SDL_Surface *surface);
  416. /**
  417. * Set the color key (transparent pixel) in a surface.
  418. *
  419. * The color key defines a pixel value that will be treated as transparent in
  420. * a blit. For example, one can use this to specify that cyan pixels should be
  421. * considered transparent, and therefore not rendered.
  422. *
  423. * It is a pixel of the format used by the surface, as generated by
  424. * SDL_MapRGB().
  425. *
  426. * RLE acceleration can substantially speed up blitting of images with large
  427. * horizontal runs of transparent pixels. See SDL_SetSurfaceRLE() for details.
  428. *
  429. * \param surface the SDL_Surface structure to update
  430. * \param flag SDL_TRUE to enable color key, SDL_FALSE to disable color key
  431. * \param key the transparent pixel
  432. * \returns 0 on success or a negative error code on failure; call
  433. * SDL_GetError() for more information.
  434. *
  435. * \since This function is available since SDL 3.0.0.
  436. *
  437. * \sa SDL_BlitSurface
  438. * \sa SDL_GetSurfaceColorKey
  439. */
  440. extern DECLSPEC int SDLCALL SDL_SetSurfaceColorKey(SDL_Surface *surface, int flag, Uint32 key);
  441. /**
  442. * Returns whether the surface has a color key
  443. *
  444. * It is safe to pass a NULL `surface` here; it will return SDL_FALSE.
  445. *
  446. * \param surface the SDL_Surface structure to query
  447. * \returns SDL_TRUE if the surface has a color key, SDL_FALSE otherwise.
  448. *
  449. * \since This function is available since SDL 3.0.0.
  450. *
  451. * \sa SDL_SetSurfaceColorKey
  452. * \sa SDL_GetSurfaceColorKey
  453. */
  454. extern DECLSPEC SDL_bool SDLCALL SDL_SurfaceHasColorKey(SDL_Surface *surface);
  455. /**
  456. * Get the color key (transparent pixel) for a surface.
  457. *
  458. * The color key is a pixel of the format used by the surface, as generated by
  459. * SDL_MapRGB().
  460. *
  461. * If the surface doesn't have color key enabled this function returns -1.
  462. *
  463. * \param surface the SDL_Surface structure to query
  464. * \param key a pointer filled in with the transparent pixel
  465. * \returns 0 on success or a negative error code on failure; call
  466. * SDL_GetError() for more information.
  467. *
  468. * \since This function is available since SDL 3.0.0.
  469. *
  470. * \sa SDL_BlitSurface
  471. * \sa SDL_SetSurfaceColorKey
  472. */
  473. extern DECLSPEC int SDLCALL SDL_GetSurfaceColorKey(SDL_Surface *surface, Uint32 *key);
  474. /**
  475. * Set an additional color value multiplied into blit operations.
  476. *
  477. * When this surface is blitted, during the blit operation each source color
  478. * channel is modulated by the appropriate color value according to the
  479. * following formula:
  480. *
  481. * `srcC = srcC * (color / 255)`
  482. *
  483. * \param surface the SDL_Surface structure to update
  484. * \param r the red color value multiplied into blit operations
  485. * \param g the green color value multiplied into blit operations
  486. * \param b the blue color value multiplied into blit operations
  487. * \returns 0 on success or a negative error code on failure; call
  488. * SDL_GetError() for more information.
  489. *
  490. * \since This function is available since SDL 3.0.0.
  491. *
  492. * \sa SDL_GetSurfaceColorMod
  493. * \sa SDL_SetSurfaceAlphaMod
  494. */
  495. extern DECLSPEC int SDLCALL SDL_SetSurfaceColorMod(SDL_Surface *surface, Uint8 r, Uint8 g, Uint8 b);
  496. /**
  497. * Get the additional color value multiplied into blit operations.
  498. *
  499. * \param surface the SDL_Surface structure to query
  500. * \param r a pointer filled in with the current red color value
  501. * \param g a pointer filled in with the current green color value
  502. * \param b a pointer filled in with the current blue color value
  503. * \returns 0 on success or a negative error code on failure; call
  504. * SDL_GetError() for more information.
  505. *
  506. * \since This function is available since SDL 3.0.0.
  507. *
  508. * \sa SDL_GetSurfaceAlphaMod
  509. * \sa SDL_SetSurfaceColorMod
  510. */
  511. extern DECLSPEC int SDLCALL SDL_GetSurfaceColorMod(SDL_Surface *surface, Uint8 *r, Uint8 *g, Uint8 *b);
  512. /**
  513. * Set an additional alpha value used in blit operations.
  514. *
  515. * When this surface is blitted, during the blit operation the source alpha
  516. * value is modulated by this alpha value according to the following formula:
  517. *
  518. * `srcA = srcA * (alpha / 255)`
  519. *
  520. * \param surface the SDL_Surface structure to update
  521. * \param alpha the alpha value multiplied into blit operations
  522. * \returns 0 on success or a negative error code on failure; call
  523. * SDL_GetError() for more information.
  524. *
  525. * \since This function is available since SDL 3.0.0.
  526. *
  527. * \sa SDL_GetSurfaceAlphaMod
  528. * \sa SDL_SetSurfaceColorMod
  529. */
  530. extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface *surface, Uint8 alpha);
  531. /**
  532. * Get the additional alpha value used in blit operations.
  533. *
  534. * \param surface the SDL_Surface structure to query
  535. * \param alpha a pointer filled in with the current alpha value
  536. * \returns 0 on success or a negative error code on failure; call
  537. * SDL_GetError() for more information.
  538. *
  539. * \since This function is available since SDL 3.0.0.
  540. *
  541. * \sa SDL_GetSurfaceColorMod
  542. * \sa SDL_SetSurfaceAlphaMod
  543. */
  544. extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface *surface, Uint8 *alpha);
  545. /**
  546. * Set the blend mode used for blit operations.
  547. *
  548. * To copy a surface to another surface (or texture) without blending with the
  549. * existing data, the blendmode of the SOURCE surface should be set to
  550. * `SDL_BLENDMODE_NONE`.
  551. *
  552. * \param surface the SDL_Surface structure to update
  553. * \param blendMode the SDL_BlendMode to use for blit blending
  554. * \returns 0 on success or a negative error code on failure; call
  555. * SDL_GetError() for more information.
  556. *
  557. * \since This function is available since SDL 3.0.0.
  558. *
  559. * \sa SDL_GetSurfaceBlendMode
  560. */
  561. extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface *surface, SDL_BlendMode blendMode);
  562. /**
  563. * Get the blend mode used for blit operations.
  564. *
  565. * \param surface the SDL_Surface structure to query
  566. * \param blendMode a pointer filled in with the current SDL_BlendMode
  567. * \returns 0 on success or a negative error code on failure; call
  568. * SDL_GetError() for more information.
  569. *
  570. * \since This function is available since SDL 3.0.0.
  571. *
  572. * \sa SDL_SetSurfaceBlendMode
  573. */
  574. extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface *surface, SDL_BlendMode *blendMode);
  575. /**
  576. * Set the clipping rectangle for a surface.
  577. *
  578. * When `surface` is the destination of a blit, only the area within the clip
  579. * rectangle is drawn into.
  580. *
  581. * Note that blits are automatically clipped to the edges of the source and
  582. * destination surfaces.
  583. *
  584. * \param surface the SDL_Surface structure to be clipped
  585. * \param rect the SDL_Rect structure representing the clipping rectangle, or
  586. * NULL to disable clipping
  587. * \returns SDL_TRUE if the rectangle intersects the surface, otherwise
  588. * SDL_FALSE and blits will be completely clipped.
  589. *
  590. * \since This function is available since SDL 3.0.0.
  591. *
  592. * \sa SDL_BlitSurface
  593. * \sa SDL_GetSurfaceClipRect
  594. */
  595. extern DECLSPEC SDL_bool SDLCALL SDL_SetSurfaceClipRect(SDL_Surface *surface, const SDL_Rect *rect);
  596. /**
  597. * Get the clipping rectangle for a surface.
  598. *
  599. * When `surface` is the destination of a blit, only the area within the clip
  600. * rectangle is drawn into.
  601. *
  602. * \param surface the SDL_Surface structure representing the surface to be
  603. * clipped
  604. * \param rect an SDL_Rect structure filled in with the clipping rectangle for
  605. * the surface
  606. * \returns 0 on success or a negative error code on failure; call
  607. * SDL_GetError() for more information.
  608. *
  609. * \since This function is available since SDL 3.0.0.
  610. *
  611. * \sa SDL_BlitSurface
  612. * \sa SDL_SetSurfaceClipRect
  613. */
  614. extern DECLSPEC int SDLCALL SDL_GetSurfaceClipRect(SDL_Surface *surface, SDL_Rect *rect);
  615. /*
  616. * Flip a surface vertically or horizontally.
  617. *
  618. * \param surface the surface to flip
  619. * \param flip the direction to flip
  620. * \returns 0 on success or a negative error code on failure; call
  621. * SDL_GetError() for more information.
  622. *
  623. * \since This function is available since SDL 3.0.0.
  624. */
  625. extern DECLSPEC int SDLCALL SDL_FlipSurface(SDL_Surface *surface, SDL_FlipMode flip);
  626. /*
  627. * Creates a new surface identical to the existing surface.
  628. *
  629. * The returned surface should be freed with SDL_DestroySurface().
  630. *
  631. * \param surface the surface to duplicate.
  632. * \returns a copy of the surface, or NULL on failure; call SDL_GetError() for
  633. * more information.
  634. *
  635. * \since This function is available since SDL 3.0.0.
  636. */
  637. extern DECLSPEC SDL_Surface *SDLCALL SDL_DuplicateSurface(SDL_Surface *surface);
  638. /**
  639. * Copy an existing surface to a new surface of the specified format.
  640. *
  641. * This function is used to optimize images for faster *repeat* blitting. This
  642. * is accomplished by converting the original and storing the result as a new
  643. * surface. The new, optimized surface can then be used as the source for
  644. * future blits, making them faster.
  645. *
  646. * \param surface the existing SDL_Surface structure to convert
  647. * \param format the SDL_PixelFormat structure that the new surface is
  648. * optimized for
  649. * \returns the new SDL_Surface structure that is created or NULL if it fails;
  650. * call SDL_GetError() for more information.
  651. *
  652. * \since This function is available since SDL 3.0.0.
  653. *
  654. * \sa SDL_CreatePixelFormat
  655. * \sa SDL_ConvertSurfaceFormat
  656. * \sa SDL_CreateSurface
  657. */
  658. extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface(SDL_Surface *surface, const SDL_PixelFormat *format);
  659. /**
  660. * Copy an existing surface to a new surface of the specified format.
  661. *
  662. * This function operates just like SDL_ConvertSurface(), but accepts an
  663. * SDL_PixelFormatEnum value instead of an SDL_PixelFormat structure. As such,
  664. * it might be easier to call but it doesn't have access to palette
  665. * information for the destination surface, in case that would be important.
  666. *
  667. * \param surface the existing SDL_Surface structure to convert
  668. * \param pixel_format the new pixel format
  669. * \returns the new SDL_Surface structure that is created or NULL if it fails;
  670. * call SDL_GetError() for more information.
  671. *
  672. * \since This function is available since SDL 3.0.0.
  673. *
  674. * \sa SDL_CreatePixelFormat
  675. * \sa SDL_ConvertSurface
  676. * \sa SDL_CreateSurface
  677. */
  678. extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurfaceFormat(SDL_Surface *surface, Uint32 pixel_format);
  679. /**
  680. * Copy an existing surface to a new surface of the specified format and
  681. * colorspace.
  682. *
  683. * This function converts an existing surface to a new format and colorspace
  684. * and returns the new surface. This will perform any pixel format and
  685. * colorspace conversion needed.
  686. *
  687. * \param surface the existing SDL_Surface structure to convert
  688. * \param pixel_format the new pixel format
  689. * \param colorspace the new colorspace
  690. * \returns the new SDL_Surface structure that is created or NULL if it fails;
  691. * call SDL_GetError() for more information.
  692. *
  693. * \since This function is available since SDL 3.0.0.
  694. *
  695. * \sa SDL_CreatePixelFormat
  696. * \sa SDL_ConvertSurface
  697. * \sa SDL_CreateSurface
  698. */
  699. extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurfaceFormatAndColorspace(SDL_Surface *surface, Uint32 pixel_format, SDL_Colorspace colorspace, SDL_PropertiesID props);
  700. /**
  701. * Copy a block of pixels of one format to another format.
  702. *
  703. * \param width the width of the block to copy, in pixels
  704. * \param height the height of the block to copy, in pixels
  705. * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format
  706. * \param src a pointer to the source pixels
  707. * \param src_pitch the pitch of the source pixels, in bytes
  708. * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format
  709. * \param dst a pointer to be filled in with new pixel data
  710. * \param dst_pitch the pitch of the destination pixels, in bytes
  711. * \returns 0 on success or a negative error code on failure; call
  712. * SDL_GetError() for more information.
  713. *
  714. * \since This function is available since SDL 3.0.0.
  715. */
  716. extern DECLSPEC int SDLCALL SDL_ConvertPixels(int width, int height, Uint32 src_format, const void *src, int src_pitch, Uint32 dst_format, void *dst, int dst_pitch);
  717. /**
  718. * Copy a block of pixels of one format and colorspace to another format and
  719. * colorspace.
  720. *
  721. * \param width the width of the block to copy, in pixels
  722. * \param height the height of the block to copy, in pixels
  723. * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format
  724. * \param src_colorspace an SDL_ColorSpace value describing the colorspace of
  725. * the `src` pixels
  726. * \param src a pointer to the source pixels
  727. * \param src_pitch the pitch of the source pixels, in bytes
  728. * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format
  729. * \param dst_colorspace an SDL_ColorSpace value describing the colorspace of
  730. * the `dst` pixels
  731. * \param dst a pointer to be filled in with new pixel data
  732. * \param dst_pitch the pitch of the destination pixels, in bytes
  733. * \returns 0 on success or a negative error code on failure; call
  734. * SDL_GetError() for more information.
  735. *
  736. * \since This function is available since SDL 3.0.0.
  737. */
  738. extern DECLSPEC int SDLCALL SDL_ConvertPixelsAndColorspace(int width, int height, Uint32 src_format, SDL_Colorspace src_colorspace, SDL_PropertiesID src_properties, const void *src, int src_pitch, Uint32 dst_format, SDL_Colorspace dst_colorspace, SDL_PropertiesID dst_properties, void *dst, int dst_pitch);
  739. /**
  740. * Premultiply the alpha on a block of pixels.
  741. *
  742. * This is safe to use with src == dst, but not for other overlapping areas.
  743. *
  744. * This function is currently only implemented for SDL_PIXELFORMAT_ARGB8888.
  745. *
  746. * \param width the width of the block to convert, in pixels
  747. * \param height the height of the block to convert, in pixels
  748. * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format
  749. * \param src a pointer to the source pixels
  750. * \param src_pitch the pitch of the source pixels, in bytes
  751. * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format
  752. * \param dst a pointer to be filled in with premultiplied pixel data
  753. * \param dst_pitch the pitch of the destination pixels, in bytes
  754. * \returns 0 on success or a negative error code on failure; call
  755. * SDL_GetError() for more information.
  756. *
  757. * \since This function is available since SDL 3.0.0.
  758. */
  759. extern DECLSPEC int SDLCALL SDL_PremultiplyAlpha(int width, int height, Uint32 src_format, const void *src, int src_pitch, Uint32 dst_format, void *dst, int dst_pitch);
  760. /**
  761. * Perform a fast fill of a rectangle with a specific color.
  762. *
  763. * `color` should be a pixel of the format used by the surface, and can be
  764. * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an
  765. * alpha component then the destination is simply filled with that alpha
  766. * information, no blending takes place.
  767. *
  768. * If there is a clip rectangle set on the destination (set via
  769. * SDL_SetSurfaceClipRect()), then this function will fill based on the
  770. * intersection of the clip rectangle and `rect`.
  771. *
  772. * \param dst the SDL_Surface structure that is the drawing target
  773. * \param rect the SDL_Rect structure representing the rectangle to fill, or
  774. * NULL to fill the entire surface
  775. * \param color the color to fill with
  776. * \returns 0 on success or a negative error code on failure; call
  777. * SDL_GetError() for more information.
  778. *
  779. * \since This function is available since SDL 3.0.0.
  780. *
  781. * \sa SDL_FillSurfaceRects
  782. */
  783. extern DECLSPEC int SDLCALL SDL_FillSurfaceRect(SDL_Surface *dst, const SDL_Rect *rect, Uint32 color);
  784. /**
  785. * Perform a fast fill of a set of rectangles with a specific color.
  786. *
  787. * `color` should be a pixel of the format used by the surface, and can be
  788. * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an
  789. * alpha component then the destination is simply filled with that alpha
  790. * information, no blending takes place.
  791. *
  792. * If there is a clip rectangle set on the destination (set via
  793. * SDL_SetSurfaceClipRect()), then this function will fill based on the
  794. * intersection of the clip rectangle and `rect`.
  795. *
  796. * \param dst the SDL_Surface structure that is the drawing target
  797. * \param rects an array of SDL_Rects representing the rectangles to fill.
  798. * \param count the number of rectangles in the array
  799. * \param color the color to fill with
  800. * \returns 0 on success or a negative error code on failure; call
  801. * SDL_GetError() for more information.
  802. *
  803. * \since This function is available since SDL 3.0.0.
  804. *
  805. * \sa SDL_FillSurfaceRect
  806. */
  807. extern DECLSPEC int SDLCALL SDL_FillSurfaceRects(SDL_Surface *dst, const SDL_Rect *rects, int count, Uint32 color);
  808. /**
  809. * Performs a fast blit from the source surface to the destination surface.
  810. *
  811. * This assumes that the source and destination rectangles are the same size.
  812. * If either `srcrect` or `dstrect` are NULL, the entire surface (`src` or
  813. * `dst`) is copied. The final blit rectangles are saved in `srcrect` and
  814. * `dstrect` after all clipping is performed.
  815. *
  816. * The blit function should not be called on a locked surface.
  817. *
  818. * The blit semantics for surfaces with and without blending and colorkey are
  819. * defined as follows:
  820. *
  821. * ```c
  822. * RGBA->RGB:
  823. * Source surface blend mode set to SDL_BLENDMODE_BLEND:
  824. * alpha-blend (using the source alpha-channel and per-surface alpha)
  825. * SDL_SRCCOLORKEY ignored.
  826. * Source surface blend mode set to SDL_BLENDMODE_NONE:
  827. * copy RGB.
  828. * if SDL_SRCCOLORKEY set, only copy the pixels matching the
  829. * RGB values of the source color key, ignoring alpha in the
  830. * comparison.
  831. *
  832. * RGB->RGBA:
  833. * Source surface blend mode set to SDL_BLENDMODE_BLEND:
  834. * alpha-blend (using the source per-surface alpha)
  835. * Source surface blend mode set to SDL_BLENDMODE_NONE:
  836. * copy RGB, set destination alpha to source per-surface alpha value.
  837. * both:
  838. * if SDL_SRCCOLORKEY set, only copy the pixels matching the
  839. * source color key.
  840. *
  841. * RGBA->RGBA:
  842. * Source surface blend mode set to SDL_BLENDMODE_BLEND:
  843. * alpha-blend (using the source alpha-channel and per-surface alpha)
  844. * SDL_SRCCOLORKEY ignored.
  845. * Source surface blend mode set to SDL_BLENDMODE_NONE:
  846. * copy all of RGBA to the destination.
  847. * if SDL_SRCCOLORKEY set, only copy the pixels matching the
  848. * RGB values of the source color key, ignoring alpha in the
  849. * comparison.
  850. *
  851. * RGB->RGB:
  852. * Source surface blend mode set to SDL_BLENDMODE_BLEND:
  853. * alpha-blend (using the source per-surface alpha)
  854. * Source surface blend mode set to SDL_BLENDMODE_NONE:
  855. * copy RGB.
  856. * both:
  857. * if SDL_SRCCOLORKEY set, only copy the pixels matching the
  858. * source color key.
  859. * ```
  860. *
  861. * \param src the SDL_Surface structure to be copied from
  862. * \param srcrect the SDL_Rect structure representing the rectangle to be
  863. * copied, or NULL to copy the entire surface
  864. * \param dst the SDL_Surface structure that is the blit target
  865. * \param dstrect the SDL_Rect structure representing the x and y position in
  866. * the destination surface. On input the width and height are
  867. * ignored (taken from srcrect), and on output this is filled
  868. * in with the actual rectangle used after clipping.
  869. * \returns 0 on success or a negative error code on failure; call
  870. * SDL_GetError() for more information.
  871. *
  872. * \since This function is available since SDL 3.0.0.
  873. *
  874. * \sa SDL_BlitSurfaceScaled
  875. */
  876. extern DECLSPEC int SDLCALL SDL_BlitSurface(SDL_Surface *src, const SDL_Rect *srcrect, SDL_Surface *dst, SDL_Rect *dstrect);
  877. /**
  878. * Perform low-level surface blitting only.
  879. *
  880. * This is a semi-private blit function and it performs low-level surface
  881. * blitting, assuming the input rectangles have already been clipped.
  882. *
  883. * \param src the SDL_Surface structure to be copied from
  884. * \param srcrect the SDL_Rect structure representing the rectangle to be
  885. * copied, or NULL to copy the entire surface
  886. * \param dst the SDL_Surface structure that is the blit target
  887. * \param dstrect the SDL_Rect structure representing the target rectangle in
  888. * the destination surface
  889. * \returns 0 on success or a negative error code on failure; call
  890. * SDL_GetError() for more information.
  891. *
  892. * \since This function is available since SDL 3.0.0.
  893. *
  894. * \sa SDL_BlitSurface
  895. */
  896. extern DECLSPEC int SDLCALL SDL_BlitSurfaceUnchecked(SDL_Surface *src, const SDL_Rect *srcrect, SDL_Surface *dst, const SDL_Rect *dstrect);
  897. /**
  898. * Perform stretch blit between two surfaces of the same format.
  899. *
  900. * Using SDL_SCALEMODE_NEAREST: fast, low quality. Using SDL_SCALEMODE_LINEAR:
  901. * bilinear scaling, slower, better quality, only 32BPP.
  902. *
  903. * \param src the SDL_Surface structure to be copied from
  904. * \param srcrect the SDL_Rect structure representing the rectangle to be
  905. * copied
  906. * \param dst the SDL_Surface structure that is the blit target
  907. * \param dstrect the SDL_Rect structure representing the target rectangle in
  908. * the destination surface
  909. * \param scaleMode scale algorithm to be used
  910. * \returns 0 on success or a negative error code on failure; call
  911. * SDL_GetError() for more information.
  912. *
  913. * \since This function is available since SDL 3.0.0.
  914. *
  915. * \sa SDL_BlitSurfaceScaled
  916. */
  917. extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface *src, const SDL_Rect *srcrect, SDL_Surface *dst, const SDL_Rect *dstrect, SDL_ScaleMode scaleMode);
  918. /**
  919. * Perform a scaled surface copy to a destination surface.
  920. *
  921. * \param src the SDL_Surface structure to be copied from
  922. * \param srcrect the SDL_Rect structure representing the rectangle to be
  923. * copied
  924. * \param dst the SDL_Surface structure that is the blit target
  925. * \param dstrect the SDL_Rect structure representing the target rectangle in
  926. * the destination surface, filled with the actual rectangle
  927. * used after clipping
  928. * \param scaleMode scale algorithm to be used
  929. * \returns 0 on success or a negative error code on failure; call
  930. * SDL_GetError() for more information.
  931. *
  932. * \since This function is available since SDL 3.0.0.
  933. *
  934. * \sa SDL_BlitSurface
  935. */
  936. extern DECLSPEC int SDLCALL SDL_BlitSurfaceScaled(SDL_Surface *src, const SDL_Rect *srcrect, SDL_Surface *dst, SDL_Rect *dstrect, SDL_ScaleMode scaleMode);
  937. /**
  938. * Perform low-level surface scaled blitting only.
  939. *
  940. * This is a semi-private function and it performs low-level surface blitting,
  941. * assuming the input rectangles have already been clipped.
  942. *
  943. * \param src the SDL_Surface structure to be copied from
  944. * \param srcrect the SDL_Rect structure representing the rectangle to be
  945. * copied
  946. * \param dst the SDL_Surface structure that is the blit target
  947. * \param dstrect the SDL_Rect structure representing the target rectangle in
  948. * the destination surface
  949. * \param scaleMode scale algorithm to be used
  950. * \returns 0 on success or a negative error code on failure; call
  951. * SDL_GetError() for more information.
  952. *
  953. * \since This function is available since SDL 3.0.0.
  954. *
  955. * \sa SDL_BlitSurfaceScaled
  956. */
  957. extern DECLSPEC int SDLCALL SDL_BlitSurfaceUncheckedScaled(SDL_Surface *src, const SDL_Rect *srcrect, SDL_Surface *dst, const SDL_Rect *dstrect, SDL_ScaleMode scaleMode);
  958. /**
  959. * Retrieves a single pixel from a surface.
  960. *
  961. * This function prioritizes correctness over speed: it is suitable for unit
  962. * tests, but is not intended for use in a game engine.
  963. *
  964. * Like SDL_GetRGBA, this uses the entire 0..255 range when converting color
  965. * components from pixel formats with less than 8 bits per RGB component.
  966. *
  967. * \param surface the surface to read
  968. * \param x the horizontal coordinate, 0 <= x < width
  969. * \param y the vertical coordinate, 0 <= y < height
  970. * \param r a pointer filled in with the red channel, 0-255, or NULL to ignore
  971. * this channel
  972. * \param g a pointer filled in with the green channel, 0-255, or NULL to
  973. * ignore this channel
  974. * \param b a pointer filled in with the blue channel, 0-255, or NULL to
  975. * ignore this channel
  976. * \param a a pointer filled in with the alpha channel, 0-255, or NULL to
  977. * ignore this channel
  978. * \returns 0 on success or a negative error code on failure; call
  979. * SDL_GetError() for more information.
  980. *
  981. * \since This function is available since SDL 3.0.0.
  982. */
  983. extern DECLSPEC int SDLCALL SDL_ReadSurfacePixel(SDL_Surface *surface, int x, int y, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a);
  984. /* Ends C function definitions when using C++ */
  985. #ifdef __cplusplus
  986. }
  987. #endif
  988. #include <SDL3/SDL_close_code.h>
  989. #endif /* SDL_surface_h_ */