assets/include/SDL2/SDL_surface.h in ruby2d-0.11.1 vs assets/include/SDL2/SDL_surface.h in ruby2d-0.11.2

- old
+ new

@@ -1,8 +1,8 @@ /* Simple DirectMedia Layer - Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org> + Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org> This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. @@ -110,112 +110,269 @@ SDL_YUV_CONVERSION_BT709, /**< BT.709 */ SDL_YUV_CONVERSION_AUTOMATIC /**< BT.601 for SD content, BT.709 for HD content */ } SDL_YUV_CONVERSION_MODE; /** - * Allocate and free an RGB surface. + * Allocate a new RGB surface. * - * If the depth is 4 or 8 bits, an empty palette is allocated for the surface. - * If the depth is greater than 8 bits, the pixel format is set using the - * flags '[RGB]mask'. + * If `depth` is 4 or 8 bits, an empty palette is allocated for the surface. + * If `depth` is greater than 8 bits, the pixel format is set using the + * [RGBA]mask parameters. * - * If the function runs out of memory, it will return NULL. + * The [RGBA]mask parameters are the bitmasks used to extract that color from + * a pixel. For instance, `Rmask` being 0xFF000000 means the red data is + * stored in the most significant byte. Using zeros for the RGB masks sets a + * default value, based on the depth. For example: * - * \param flags The \c flags are obsolete and should be set to 0. - * \param width The width in pixels of the surface to create. - * \param height The height in pixels of the surface to create. - * \param depth The depth in bits of the surface to create. - * \param Rmask The red mask of the surface to create. - * \param Gmask The green mask of the surface to create. - * \param Bmask The blue mask of the surface to create. - * \param Amask The alpha mask of the surface to create. + * ```c++ + * SDL_CreateRGBSurface(0,w,h,32,0,0,0,0); + * ``` + * + * However, using zero for the Amask results in an Amask of 0. + * + * By default surfaces with an alpha mask are set up for blending as with: + * + * ```c++ + * SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND) + * ``` + * + * You can change this by calling SDL_SetSurfaceBlendMode() and selecting a + * different `blendMode`. + * + * \param flags the flags are unused and should be set to 0 + * \param width the width of the surface + * \param height the height of the surface + * \param depth the depth of the surface in bits + * \param Rmask the red mask for the pixels + * \param Gmask the green mask for the pixels + * \param Bmask the blue mask for the pixels + * \param Amask the alpha mask for the pixels + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_CreateRGBSurfaceFrom + * \sa SDL_CreateRGBSurfaceWithFormat + * \sa SDL_FreeSurface */ extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface (Uint32 flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask); + /* !!! FIXME for 2.1: why does this ask for depth? Format provides that. */ + +/** + * Allocate a new RGB surface with a specific pixel format. + * + * This function operates mostly like SDL_CreateRGBSurface(), except instead + * of providing pixel color masks, you provide it with a predefined format + * from SDL_PixelFormatEnum. + * + * \param flags the flags are unused and should be set to 0 + * \param width the width of the surface + * \param height the height of the surface + * \param depth the depth of the surface in bits + * \param format the SDL_PixelFormatEnum for the new surface's pixel format. + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.5. + * + * \sa SDL_CreateRGBSurface + * \sa SDL_CreateRGBSurfaceFrom + * \sa SDL_FreeSurface + */ extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormat (Uint32 flags, int width, int height, int depth, Uint32 format); +/** + * Allocate a new RGB surface with existing pixel data. + * + * This function operates mostly like SDL_CreateRGBSurface(), except it does + * not allocate memory for the pixel data, instead the caller provides an + * existing buffer of data for the surface to use. + * + * No copy is made of the pixel data. Pixel data is not managed automatically; + * you must free the surface before you free the pixel data. + * + * \param pixels a pointer to existing pixel data + * \param width the width of the surface + * \param height the height of the surface + * \param depth the depth of the surface in bits + * \param pitch the pitch of the surface in bytes + * \param Rmask the red mask for the pixels + * \param Gmask the green mask for the pixels + * \param Bmask the blue mask for the pixels + * \param Amask the alpha mask for the pixels + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_CreateRGBSurface + * \sa SDL_CreateRGBSurfaceWithFormat + * \sa SDL_FreeSurface + */ extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceFrom(void *pixels, int width, int height, int depth, int pitch, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask); + +/* !!! FIXME for 2.1: why does this ask for depth? Format provides that. */ + +/** + * Allocate a new RGB surface with with a specific pixel format and existing + * pixel data. + * + * This function operates mostly like SDL_CreateRGBSurfaceFrom(), except + * instead of providing pixel color masks, you provide it with a predefined + * format from SDL_PixelFormatEnum. + * + * No copy is made of the pixel data. Pixel data is not managed automatically; + * you must free the surface before you free the pixel data. + * + * \param pixels a pointer to existing pixel data + * \param width the width of the surface + * \param height the height of the surface + * \param depth the depth of the surface in bits + * \param pitch the pitch of the surface in bytes + * \param format the SDL_PixelFormatEnum for the new surface's pixel format. + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.5. + * + * \sa SDL_CreateRGBSurfaceFrom + * \sa SDL_CreateRGBSurfaceWithFormat + * \sa SDL_FreeSurface + */ extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurfaceWithFormatFrom (void *pixels, int width, int height, int depth, int pitch, Uint32 format); + +/** + * Free an RGB surface. + * + * It is safe to pass NULL to this function. + * + * \param surface the SDL_Surface to free. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_CreateRGBSurface + * \sa SDL_CreateRGBSurfaceFrom + * \sa SDL_LoadBMP + * \sa SDL_LoadBMP_RW + */ extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface); /** - * \brief Set the palette used by a surface. + * Set the palette used by a surface. * - * \return 0, or -1 if the surface format doesn't use a palette. + * A single palette can be shared with many surfaces. * - * \note A single palette can be shared with many surfaces. + * \param surface the SDL_Surface structure to update + * \param palette the SDL_Palette structure to use + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. */ extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface, SDL_Palette * palette); /** - * \brief Sets up a surface for directly accessing the pixels. + * Set up a surface for directly accessing the pixels. * - * Between calls to SDL_LockSurface() / SDL_UnlockSurface(), you can write - * to and read from \c surface->pixels, using the pixel format stored in - * \c surface->format. Once you are done accessing the surface, you should - * use SDL_UnlockSurface() to release it. + * Between calls to SDL_LockSurface() / SDL_UnlockSurface(), you can write to + * and read from `surface->pixels`, using the pixel format stored in + * `surface->format`. Once you are done accessing the surface, you should use + * SDL_UnlockSurface() to release it. * - * Not all surfaces require locking. If SDL_MUSTLOCK(surface) evaluates - * to 0, then you can read and write to the surface at any time, and the - * pixel format of the surface will not change. + * Not all surfaces require locking. If `SDL_MUSTLOCK(surface)` evaluates to + * 0, then you can read and write to the surface at any time, and the pixel + * format of the surface will not change. * - * No operating system or library calls should be made between lock/unlock - * pairs, as critical system locks may be held during this time. + * \param surface the SDL_Surface structure to be locked + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked. + * \since This function is available since SDL 2.0.0. * - * \sa SDL_UnlockSurface() + * \sa SDL_MUSTLOCK + * \sa SDL_UnlockSurface */ extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface); -/** \sa SDL_LockSurface() */ + +/** + * Release a surface after directly accessing the pixels. + * + * \param surface the SDL_Surface structure to be unlocked + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_LockSurface + */ extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface); /** - * Load a surface from a seekable SDL data stream (memory or file). + * Load a BMP image from a seekable SDL data stream. * - * If \c freesrc is non-zero, the stream will be closed after being read. + * The new surface should be freed with SDL_FreeSurface(). Not doing so will + * result in a memory leak. * - * The new surface should be freed with SDL_FreeSurface(). + * src is an open SDL_RWops buffer, typically loaded with SDL_RWFromFile. + * Alternitavely, you might also use the macro SDL_LoadBMP to load a bitmap + * from a file, convert it to an SDL_Surface and then close the file. * - * \return the new surface, or NULL if there was an error. + * \param src the data stream for the surface + * \param freesrc non-zero to close the stream after being read + * \returns a pointer to a new SDL_Surface structure or NULL if there was an + * error; call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_FreeSurface + * \sa SDL_RWFromFile + * \sa SDL_LoadBMP + * \sa SDL_SaveBMP_RW */ extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src, int freesrc); /** - * Load a surface from a file. + * Load a surface from a file. * - * Convenience macro. + * Convenience macro. */ #define SDL_LoadBMP(file) SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1) /** - * Save a surface to a seekable SDL data stream (memory or file). + * Save a surface to a seekable SDL data stream in BMP format. * - * Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the - * BMP directly. Other RGB formats with 8-bit or higher get converted to a - * 24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit - * surface before they are saved. YUV and paletted 1-bit and 4-bit formats are - * not supported. + * Surfaces with a 24-bit, 32-bit and paletted 8-bit format get saved in the + * BMP directly. Other RGB formats with 8-bit or higher get converted to a + * 24-bit surface or, if they have an alpha mask or a colorkey, to a 32-bit + * surface before they are saved. YUV and paletted 1-bit and 4-bit formats are + * not supported. * - * If \c freedst is non-zero, the stream will be closed after being written. + * \param surface the SDL_Surface structure containing the image to be saved + * \param dst a data stream to save to + * \param freedst non-zero to close the stream after being written + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * \return 0 if successful or -1 if there was an error. + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_LoadBMP_RW + * \sa SDL_SaveBMP */ extern DECLSPEC int SDLCALL SDL_SaveBMP_RW (SDL_Surface * surface, SDL_RWops * dst, int freedst); /** @@ -225,225 +382,434 @@ */ #define SDL_SaveBMP(surface, file) \ SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1) /** - * \brief Sets the RLE acceleration hint for a surface. + * Set the RLE acceleration hint for a surface. * - * \return 0 on success, or -1 if the surface is not valid + * If RLE is enabled, color key and alpha blending blits are much faster, but + * the surface must be locked before directly accessing the pixels. * - * \note If RLE is enabled, colorkey and alpha blending blits are much faster, - * but the surface must be locked before directly accessing the pixels. + * \param surface the SDL_Surface structure to optimize + * \param flag 0 to disable, non-zero to enable RLE acceleration + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface + * \sa SDL_LockSurface + * \sa SDL_UnlockSurface */ extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface, int flag); /** - * \brief Returns whether the surface is RLE enabled + * Returns whether the surface is RLE enabled * - * \return SDL_TRUE if the surface is RLE enabled, or SDL_FALSE if the surface is NULL or not RLE enabled + * It is safe to pass a NULL `surface` here; it will return SDL_FALSE. + * + * \param surface the SDL_Surface structure to query + * \returns SDL_TRUE if the surface is RLE enabled, SDL_FALSE otherwise. + * + * \since This function is available since SDL 2.0.14. + * + * \sa SDL_SetSurfaceRLE */ extern DECLSPEC SDL_bool SDLCALL SDL_HasSurfaceRLE(SDL_Surface * surface); /** - * \brief Sets the color key (transparent pixel) in a blittable surface. + * Set the color key (transparent pixel) in a surface. * - * \param surface The surface to update - * \param flag Non-zero to enable colorkey and 0 to disable colorkey - * \param key The transparent pixel in the native surface format + * The color key defines a pixel value that will be treated as transparent in + * a blit. For example, one can use this to specify that cyan pixels should be + * considered transparent, and therefore not rendered. * - * \return 0 on success, or -1 if the surface is not valid + * It is a pixel of the format used by the surface, as generated by + * SDL_MapRGB(). * - * You can pass SDL_RLEACCEL to enable RLE accelerated blits. + * RLE acceleration can substantially speed up blitting of images with large + * horizontal runs of transparent pixels. See SDL_SetSurfaceRLE() for details. + * + * \param surface the SDL_Surface structure to update + * \param flag SDL_TRUE to enable color key, SDL_FALSE to disable color key + * \param key the transparent pixel + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface + * \sa SDL_GetColorKey */ extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface, int flag, Uint32 key); /** - * \brief Returns whether the surface has a color key + * Returns whether the surface has a color key * - * \return SDL_TRUE if the surface has a color key, or SDL_FALSE if the surface is NULL or has no color key + * It is safe to pass a NULL `surface` here; it will return SDL_FALSE. + * + * \param surface the SDL_Surface structure to query + * \return SDL_TRUE if the surface has a color key, SDL_FALSE otherwise. + * + * \since This function is available since SDL 2.0.9. + * + * \sa SDL_SetColorKey + * \sa SDL_GetColorKey */ extern DECLSPEC SDL_bool SDLCALL SDL_HasColorKey(SDL_Surface * surface); /** - * \brief Gets the color key (transparent pixel) in a blittable surface. + * Get the color key (transparent pixel) for a surface. * - * \param surface The surface to update - * \param key A pointer filled in with the transparent pixel in the native - * surface format + * The color key is a pixel of the format used by the surface, as generated by + * SDL_MapRGB(). * - * \return 0 on success, or -1 if the surface is not valid or colorkey is not - * enabled. + * If the surface doesn't have color key enabled this function returns -1. + * + * \param surface the SDL_Surface structure to query + * \param key a pointer filled in with the transparent pixel + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface + * \sa SDL_SetColorKey */ extern DECLSPEC int SDLCALL SDL_GetColorKey(SDL_Surface * surface, Uint32 * key); /** - * \brief Set an additional color value used in blit operations. + * Set an additional color value multiplied into blit operations. * - * \param surface The surface to update. - * \param r The red color value multiplied into blit operations. - * \param g The green color value multiplied into blit operations. - * \param b The blue color value multiplied into blit operations. + * When this surface is blitted, during the blit operation each source color + * channel is modulated by the appropriate color value according to the + * following formula: * - * \return 0 on success, or -1 if the surface is not valid. + * `srcC = srcC * (color / 255)` * - * \sa SDL_GetSurfaceColorMod() + * \param surface the SDL_Surface structure to update + * \param r the red color value multiplied into blit operations + * \param g the green color value multiplied into blit operations + * \param b the blue color value multiplied into blit operations + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_GetSurfaceColorMod + * \sa SDL_SetSurfaceAlphaMod */ extern DECLSPEC int SDLCALL SDL_SetSurfaceColorMod(SDL_Surface * surface, Uint8 r, Uint8 g, Uint8 b); /** - * \brief Get the additional color value used in blit operations. + * Get the additional color value multiplied into blit operations. * - * \param surface The surface to query. - * \param r A pointer filled in with the current red color value. - * \param g A pointer filled in with the current green color value. - * \param b A pointer filled in with the current blue color value. + * \param surface the SDL_Surface structure to query + * \param r a pointer filled in with the current red color value + * \param g a pointer filled in with the current green color value + * \param b a pointer filled in with the current blue color value + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * \return 0 on success, or -1 if the surface is not valid. + * \since This function is available since SDL 2.0.0. * - * \sa SDL_SetSurfaceColorMod() + * \sa SDL_GetSurfaceAlphaMod + * \sa SDL_SetSurfaceColorMod */ extern DECLSPEC int SDLCALL SDL_GetSurfaceColorMod(SDL_Surface * surface, Uint8 * r, Uint8 * g, Uint8 * b); /** - * \brief Set an additional alpha value used in blit operations. + * Set an additional alpha value used in blit operations. * - * \param surface The surface to update. - * \param alpha The alpha value multiplied into blit operations. + * When this surface is blitted, during the blit operation the source alpha + * value is modulated by this alpha value according to the following formula: * - * \return 0 on success, or -1 if the surface is not valid. + * `srcA = srcA * (alpha / 255)` * - * \sa SDL_GetSurfaceAlphaMod() + * \param surface the SDL_Surface structure to update + * \param alpha the alpha value multiplied into blit operations + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_GetSurfaceAlphaMod + * \sa SDL_SetSurfaceColorMod */ extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface * surface, Uint8 alpha); /** - * \brief Get the additional alpha value used in blit operations. + * Get the additional alpha value used in blit operations. * - * \param surface The surface to query. - * \param alpha A pointer filled in with the current alpha value. + * \param surface the SDL_Surface structure to query + * \param alpha a pointer filled in with the current alpha value + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * \return 0 on success, or -1 if the surface is not valid. + * \since This function is available since SDL 2.0.0. * - * \sa SDL_SetSurfaceAlphaMod() + * \sa SDL_GetSurfaceColorMod + * \sa SDL_SetSurfaceAlphaMod */ extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface * surface, Uint8 * alpha); /** - * \brief Set the blend mode used for blit operations. + * Set the blend mode used for blit operations. * - * \param surface The surface to update. - * \param blendMode ::SDL_BlendMode to use for blit blending. + * To copy a surface to another surface (or texture) without blending with the + * existing data, the blendmode of the SOURCE surface should be set to + * `SDL_BLENDMODE_NONE`. * - * \return 0 on success, or -1 if the parameters are not valid. + * \param surface the SDL_Surface structure to update + * \param blendMode the SDL_BlendMode to use for blit blending + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * \sa SDL_GetSurfaceBlendMode() + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_GetSurfaceBlendMode */ extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface * surface, SDL_BlendMode blendMode); /** - * \brief Get the blend mode used for blit operations. + * Get the blend mode used for blit operations. * - * \param surface The surface to query. - * \param blendMode A pointer filled in with the current blend mode. + * \param surface the SDL_Surface structure to query + * \param blendMode a pointer filled in with the current SDL_BlendMode + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. * - * \return 0 on success, or -1 if the surface is not valid. + * \since This function is available since SDL 2.0.0. * - * \sa SDL_SetSurfaceBlendMode() + * \sa SDL_SetSurfaceBlendMode */ extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface * surface, SDL_BlendMode *blendMode); /** - * Sets the clipping rectangle for the destination surface in a blit. + * Set the clipping rectangle for a surface. * - * If the clip rectangle is NULL, clipping will be disabled. + * When `surface` is the destination of a blit, only the area within the clip + * rectangle is drawn into. * - * If the clip rectangle doesn't intersect the surface, the function will - * return SDL_FALSE and blits will be completely clipped. Otherwise the - * function returns SDL_TRUE and blits to the surface will be clipped to - * the intersection of the surface area and the clipping rectangle. + * Note that blits are automatically clipped to the edges of the source and + * destination surfaces. * - * Note that blits are automatically clipped to the edges of the source - * and destination surfaces. + * \param surface the SDL_Surface structure to be clipped + * \param rect the SDL_Rect structure representing the clipping rectangle, or + * NULL to disable clipping + * \returns SDL_TRUE if the rectangle intersects the surface, otherwise + * SDL_FALSE and blits will be completely clipped. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface + * \sa SDL_GetClipRect */ extern DECLSPEC SDL_bool SDLCALL SDL_SetClipRect(SDL_Surface * surface, const SDL_Rect * rect); /** - * Gets the clipping rectangle for the destination surface in a blit. + * Get the clipping rectangle for a surface. * - * \c rect must be a pointer to a valid rectangle which will be filled - * with the correct values. + * When `surface` is the destination of a blit, only the area within the clip + * rectangle is drawn into. + * + * \param surface the SDL_Surface structure representing the surface to be + * clipped + * \param rect an SDL_Rect structure filled in with the clipping rectangle for + * the surface + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface + * \sa SDL_SetClipRect */ extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface, SDL_Rect * rect); /* - * Creates a new surface identical to the existing surface + * Creates a new surface identical to the existing surface. + * + * The returned surface should be freed with SDL_FreeSurface(). + * + * \param surface the surface to duplicate. + * \returns a copy of the surface, or NULL on failure; call SDL_GetError() for + * more information. */ extern DECLSPEC SDL_Surface *SDLCALL SDL_DuplicateSurface(SDL_Surface * surface); /** - * Creates a new surface of the specified format, and then copies and maps - * the given surface to it so the blit of the converted surface will be as - * fast as possible. If this function fails, it returns NULL. + * Copy an existing surface to a new surface of the specified format. * - * The \c flags parameter is passed to SDL_CreateRGBSurface() and has those - * semantics. You can also pass ::SDL_RLEACCEL in the flags parameter and - * SDL will try to RLE accelerate colorkey and alpha blits in the resulting - * surface. + * This function is used to optimize images for faster *repeat* blitting. This + * is accomplished by converting the original and storing the result as a new + * surface. The new, optimized surface can then be used as the source for + * future blits, making them faster. + * + * \param src the existing SDL_Surface structure to convert + * \param fmt the SDL_PixelFormat structure that the new surface is optimized + * for + * \param flags the flags are unused and should be set to 0; this is a + * leftover from SDL 1.2's API + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_AllocFormat + * \sa SDL_ConvertSurfaceFormat + * \sa SDL_CreateRGBSurface */ extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface (SDL_Surface * src, const SDL_PixelFormat * fmt, Uint32 flags); + +/** + * Copy an existing surface to a new surface of the specified format enum. + * + * This function operates just like SDL_ConvertSurface(), but accepts an + * SDL_PixelFormatEnum value instead of an SDL_PixelFormat structure. As such, + * it might be easier to call but it doesn't have access to palette + * information for the destination surface, in case that would be important. + * + * \param src the existing SDL_Surface structure to convert + * \param pixel_format the SDL_PixelFormatEnum that the new surface is + * optimized for + * \param flags the flags are unused and should be set to 0; this is a + * leftover from SDL 1.2's API + * \returns the new SDL_Surface structure that is created or NULL if it fails; + * call SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_AllocFormat + * \sa SDL_ConvertSurface + * \sa SDL_CreateRGBSurface + */ extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurfaceFormat (SDL_Surface * src, Uint32 pixel_format, Uint32 flags); /** - * \brief Copy a block of pixels of one format to another format + * Copy a block of pixels of one format to another format. * - * \return 0 on success, or -1 if there was an error + * \param width the width of the block to copy, in pixels + * \param height the height of the block to copy, in pixels + * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format + * \param src a pointer to the source pixels + * \param src_pitch the pitch of the source pixels, in bytes + * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format + * \param dst a pointer to be filled in with new pixel data + * \param dst_pitch the pitch of the destination pixels, in bytes + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. */ 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); /** - * Performs a fast fill of the given rectangle with \c color. + * Premultiply the alpha on a block of pixels. * - * If \c rect is NULL, the whole surface will be filled with \c color. + * This is safe to use with src == dst, but not for other overlapping areas. * - * The color should be a pixel of the format used by the surface, and - * can be generated by the SDL_MapRGB() function. + * This function is currently only implemented for SDL_PIXELFORMAT_ARGB8888. * - * \return 0 on success, or -1 on error. + * \param width the width of the block to convert, in pixels + * \param height the height of the block to convert, in pixels + * \param src_format an SDL_PixelFormatEnum value of the `src` pixels format + * \param src a pointer to the source pixels + * \param src_pitch the pitch of the source pixels, in bytes + * \param dst_format an SDL_PixelFormatEnum value of the `dst` pixels format + * \param dst a pointer to be filled in with premultiplied pixel data + * \param dst_pitch the pitch of the destination pixels, in bytes + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.18. */ +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); + +/** + * Perform a fast fill of a rectangle with a specific color. + * + * `color` should be a pixel of the format used by the surface, and can be + * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an + * alpha component then the destination is simply filled with that alpha + * information, no blending takes place. + * + * If there is a clip rectangle set on the destination (set via + * SDL_SetClipRect()), then this function will fill based on the intersection + * of the clip rectangle and `rect`. + * + * \param dst the SDL_Surface structure that is the drawing target + * \param rect the SDL_Rect structure representing the rectangle to fill, or + * NULL to fill the entire surface + * \param color the color to fill with + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_FillRects + */ extern DECLSPEC int SDLCALL SDL_FillRect (SDL_Surface * dst, const SDL_Rect * rect, Uint32 color); + +/** + * Perform a fast fill of a set of rectangles with a specific color. + * + * `color` should be a pixel of the format used by the surface, and can be + * generated by SDL_MapRGB() or SDL_MapRGBA(). If the color value contains an + * alpha component then the destination is simply filled with that alpha + * information, no blending takes place. + * + * If there is a clip rectangle set on the destination (set via + * SDL_SetClipRect()), then this function will fill based on the intersection + * of the clip rectangle and `rect`. + * + * \param dst the SDL_Surface structure that is the drawing target + * \param rects an array of SDL_Rects representing the rectangles to fill. + * \param count the number of rectangles in the array + * \param color the color to fill with + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_FillRect + */ extern DECLSPEC int SDLCALL SDL_FillRects (SDL_Surface * dst, const SDL_Rect * rects, int count, Uint32 color); +/* !!! FIXME: merge this documentation with the wiki */ /** * Performs a fast blit from the source surface to the destination surface. * * This assumes that the source and destination rectangles are * the same size. If either \c srcrect or \c dstrect are NULL, the entire * surface (\c src or \c dst) is copied. The final blit rectangles are saved * in \c srcrect and \c dstrect after all clipping is performed. * - * \return If the blit is successful, it returns 0, otherwise it returns -1. + * \returns 0 if the blit is successful, otherwise it returns -1. * * The blit function should not be called on a locked surface. * * The blit semantics for surfaces with and without blending and colorkey * are defined as follows: @@ -491,65 +857,131 @@ * blitting works internally and how to use the other blit functions. */ #define SDL_BlitSurface SDL_UpperBlit /** - * This is the public blit function, SDL_BlitSurface(), and it performs - * rectangle validation and clipping before passing it to SDL_LowerBlit() + * Perform a fast blit from the source surface to the destination surface. + * + * SDL_UpperBlit() has been replaced by SDL_BlitSurface(), which is merely a + * macro for this function with a less confusing name. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface */ extern DECLSPEC int SDLCALL SDL_UpperBlit (SDL_Surface * src, const SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect); /** - * This is a semi-private blit function and it performs low-level surface - * blitting only. + * Perform low-level surface blitting only. + * + * This is a semi-private blit function and it performs low-level surface + * blitting, assuming the input rectangles have already been clipped. + * + * Unless you know what you're doing, you should be using SDL_BlitSurface() + * instead. + * + * \param src the SDL_Surface structure to be copied from + * \param srcrect the SDL_Rect structure representing the rectangle to be + * copied, or NULL to copy the entire surface + * \param dst the SDL_Surface structure that is the blit target + * \param dstrect the SDL_Rect structure representing the rectangle that is + * copied into + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitSurface */ extern DECLSPEC int SDLCALL SDL_LowerBlit (SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect); + /** - * \brief Perform a fast, low quality, stretch blit between two surfaces of the - * same pixel format. + * Perform a fast, low quality, stretch blit between two surfaces of the same + * format. * - * \note This function uses a static buffer, and is not thread-safe. + * Please use SDL_BlitScaled() instead. + * + * \since This function is available since SDL 2.0.0. */ extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src, const SDL_Rect * srcrect, SDL_Surface * dst, const SDL_Rect * dstrect); +/** + * Perform bilinear scaling between two surfaces of the same format, 32BPP. + * + * \since This function is available since SDL 2.0.16. + */ +extern DECLSPEC int SDLCALL SDL_SoftStretchLinear(SDL_Surface * src, + const SDL_Rect * srcrect, + SDL_Surface * dst, + const SDL_Rect * dstrect); + + #define SDL_BlitScaled SDL_UpperBlitScaled /** - * This is the public scaled blit function, SDL_BlitScaled(), and it performs - * rectangle validation and clipping before passing it to SDL_LowerBlitScaled() + * Perform a scaled surface copy to a destination surface. + * + * SDL_UpperBlitScaled() has been replaced by SDL_BlitScaled(), which is + * merely a macro for this function with a less confusing name. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitScaled */ extern DECLSPEC int SDLCALL SDL_UpperBlitScaled (SDL_Surface * src, const SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect); /** - * This is a semi-private blit function and it performs low-level surface - * scaled blitting only. + * Perform low-level surface scaled blitting only. + * + * This is a semi-private function and it performs low-level surface blitting, + * assuming the input rectangles have already been clipped. + * + * \param src the SDL_Surface structure to be copied from + * \param srcrect the SDL_Rect structure representing the rectangle to be + * copied + * \param dst the SDL_Surface structure that is the blit target + * \param dstrect the SDL_Rect structure representing the rectangle that is + * copied into + * \returns 0 on success or a negative error code on failure; call + * SDL_GetError() for more information. + * + * \since This function is available since SDL 2.0.0. + * + * \sa SDL_BlitScaled */ extern DECLSPEC int SDLCALL SDL_LowerBlitScaled (SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect); /** - * \brief Set the YUV conversion mode + * Set the YUV conversion mode + * + * \since This function is available since SDL 2.0.8. */ extern DECLSPEC void SDLCALL SDL_SetYUVConversionMode(SDL_YUV_CONVERSION_MODE mode); /** - * \brief Get the YUV conversion mode + * Get the YUV conversion mode + * + * \since This function is available since SDL 2.0.8. */ extern DECLSPEC SDL_YUV_CONVERSION_MODE SDLCALL SDL_GetYUVConversionMode(void); /** - * \brief Get the YUV conversion mode, returning the correct mode for the resolution when the current conversion mode is SDL_YUV_CONVERSION_AUTOMATIC + * Get the YUV conversion mode, returning the correct mode for the resolution + * when the current conversion mode is SDL_YUV_CONVERSION_AUTOMATIC + * + * \since This function is available since SDL 2.0.8. */ extern DECLSPEC SDL_YUV_CONVERSION_MODE SDLCALL SDL_GetYUVConversionModeForResolution(int width, int height); /* Ends C function definitions when using C++ */ #ifdef __cplusplus