Mercurial > sdl-ios-xcode
diff include/SDL_surface.h @ 3407:d3baf5ac4e37
Partial fix for bug #859
Header file update from Ken for improved doxygen output
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 19 Oct 2009 13:31:58 +0000 |
parents | 710139a1692d |
children | 147d6ef5be03 |
line wrap: on
line diff
--- a/include/SDL_surface.h Sun Oct 18 23:21:15 2009 +0000 +++ b/include/SDL_surface.h Mon Oct 19 13:31:58 2009 +0000 @@ -21,9 +21,9 @@ */ /** - * \file SDL_surface.h - * - * Header file for SDL_surface definition and management functions + * \file SDL_surface.h + * + * Header file for ::SDL_surface definition and management functions. */ #ifndef _SDL_surface_h @@ -42,21 +42,28 @@ /* *INDENT-ON* */ #endif -/** These are the currently supported flags for the SDL_surface - * \internal Used internally (read-only) +/** + * \name Surface flags + * + * These are the currently supported flags for the ::SDL_surface. + * + * \internal + * Used internally (read-only). */ /*@{*/ #define SDL_PREALLOC 0x00000001 /**< Surface uses preallocated memory */ #define SDL_RLEACCEL 0x00000002 /**< Surface is RLE encoded */ -/*@}*/ +/*@}*//*Surface flags*/ -/** Evaluates to true if the surface needs to be locked before access */ +/** + * Evaluates to true if the surface needs to be locked before access. + */ #define SDL_MUSTLOCK(S) (((S)->flags & SDL_RLEACCEL) != 0) /** - * \brief A collection of pixels used in software blitting + * \brief A collection of pixels used in software blitting. * - * \note This structure should be treated as read-only, except for 'pixels', + * \note This structure should be treated as read-only, except for \c pixels, * which, if not NULL, contains the raw pixel data for the surface. */ typedef struct SDL_Surface @@ -67,40 +74,42 @@ int pitch; /**< Read-only */ void *pixels; /**< Read-write */ - /* Application data associated with the surfade */ + /** Application data associated with the surfade */ void *userdata; /**< Read-write */ - /* information needed for surfaces requiring locks */ + /** information needed for surfaces requiring locks */ int locked; /**< Read-only */ void *lock_data; /**< Read-only */ - /* clipping information */ + /** clipping information */ SDL_Rect clip_rect; /**< Read-only */ - /* info for fast blit mapping to other surfaces */ + /** info for fast blit mapping to other surfaces */ struct SDL_BlitMap *map; /**< Private */ - /* format version, bumped at every change to invalidate blit maps */ + /** format version, bumped at every change to invalidate blit maps */ unsigned int format_version; /**< Private */ - /* Reference count -- used when freeing surface */ + /** Reference count -- used when freeing surface */ int refcount; /**< Read-mostly */ } SDL_Surface; /** - * \brief The type of function used for surface blitting functions + * \brief The type of function used for surface blitting functions. */ typedef int (*SDL_blit) (struct SDL_Surface * src, SDL_Rect * srcrect, struct SDL_Surface * dst, SDL_Rect * dstrect); /** - * Allocate and free an RGB surface (must be called after SDL_SetVideoMode) - * 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 the function runs out of memory, it will return NULL. - * - * \param flags The 'flags' are obsolete and should be set to 0. + * Allocate and free an RGB surface (must be called after SDL_SetVideoMode). + * + * 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 the function runs out of memory, it will return NULL. + * + * \param flags The \c flags are obsolete and should be set to 0. */ extern DECLSPEC SDL_Surface *SDLCALL SDL_CreateRGBSurface (Uint32 flags, int width, int height, int depth, @@ -117,387 +126,426 @@ extern DECLSPEC void SDLCALL SDL_FreeSurface(SDL_Surface * surface); /** - * \brief Set the palette used by a surface. - * - * \return 0, or -1 if the surface format doesn't use a palette. - * - * \note A single palette can be shared with many surfaces. + * \brief Set the palette used by a surface. + * + * \return 0, or -1 if the surface format doesn't use a palette. + * + * \note A single palette can be shared with many surfaces. */ extern DECLSPEC int SDLCALL SDL_SetSurfacePalette(SDL_Surface * surface, SDL_Palette * palette); /** - * \brief Sets up a surface for directly accessing the pixels. - * - * 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. - * - * No operating system or library calls should be made between lock/unlock - * pairs, as critical system locks may be held during this time. - * - * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked. - * - * \sa SDL_UnlockSurface() + * \brief Sets 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. + * + * 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. + * + * SDL_LockSurface() returns 0, or -1 if the surface couldn't be locked. + * + * \sa SDL_UnlockSurface() */ extern DECLSPEC int SDLCALL SDL_LockSurface(SDL_Surface * surface); /** \sa SDL_LockSurface() */ extern DECLSPEC void SDLCALL SDL_UnlockSurface(SDL_Surface * surface); /** - * Load a surface from a seekable SDL data source (memory or file.) - * If 'freesrc' is non-zero, the source will be closed after being read. - * Returns the new surface, or NULL if there was an error. - * The new surface should be freed with SDL_FreeSurface(). + * Load a surface from a seekable SDL data source (memory or file). + * + * If \c freesrc is non-zero, the source will be closed after being read. + * + * The new surface should be freed with SDL_FreeSurface(). + * + * \return the new surface, or NULL if there was an error. */ extern DECLSPEC SDL_Surface *SDLCALL SDL_LoadBMP_RW(SDL_RWops * src, int freesrc); -/** Convenience macro -- load a surface from a file */ +/** + * Load a surface from a file. + * + * Convenience macro. + */ #define SDL_LoadBMP(file) SDL_LoadBMP_RW(SDL_RWFromFile(file, "rb"), 1) /** - * Save a surface to a seekable SDL data source (memory or file.) - * If 'freedst' is non-zero, the source will be closed after being written. - * Returns 0 if successful or -1 if there was an error. + * Save a surface to a seekable SDL data source (memory or file). + * + * If \c freedst is non-zero, the source will be closed after being written. + * + * \return 0 if successful or -1 if there was an error. */ extern DECLSPEC int SDLCALL SDL_SaveBMP_RW (SDL_Surface * surface, SDL_RWops * dst, int freedst); -/** Convenience macro -- save a surface to a file */ +/** + * Save a surface to a file. + * + * Convenience macro. + */ #define SDL_SaveBMP(surface, file) \ SDL_SaveBMP_RW(surface, SDL_RWFromFile(file, "wb"), 1) /** - * \brief Sets the RLE acceleration hint for a surface. - * - * \return 0 on success, or -1 if the surface is not valid - * - * \note If RLE is enabled, colorkey and alpha blending blits are much faster, - * but the surface must be locked before directly accessing the pixels. + * \brief Sets the RLE acceleration hint for a surface. + * + * \return 0 on success, or -1 if the surface is not valid + * + * \note If RLE is enabled, colorkey and alpha blending blits are much faster, + * but the surface must be locked before directly accessing the pixels. */ extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface, int flag); /** - * \brief Sets the color key (transparent pixel) in a blittable 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 - * - * \return 0 on success, or -1 if the surface is not valid + * \brief Sets the color key (transparent pixel) in a blittable 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 + * + * \return 0 on success, or -1 if the surface is not valid */ extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface, Uint32 flag, Uint32 key); /** - * \brief Sets the color key (transparent pixel) in a blittable surface. - * - * \param surface The surface to update - * \param key A pointer filled in with the transparent pixel in the native surface format - * - * \return 0 on success, or -1 if the surface is not valid or colorkey is not enabled. + * \brief Sets the color key (transparent pixel) in a blittable surface. + * + * \param surface The surface to update + * \param key A pointer filled in with the transparent pixel in the native + * surface format + * + * \return 0 on success, or -1 if the surface is not valid or colorkey is not + * enabled. */ extern DECLSPEC int SDLCALL SDL_GetColorKey(SDL_Surface * surface, Uint32 * key); /** - * \brief Set an additional color value used in blit operations - * - * \param surface The surface to update - * \param r The red source color value multiplied into blit operations - * \param g The green source color value multiplied into blit operations - * \param b The blue source color value multiplied into blit operations - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_GetSurfaceColorMod() + * \brief Set an additional color value used in blit operations. + * + * \param surface The surface to update. + * \param r The red source color value multiplied into blit operations. + * \param g The green source color value multiplied into blit operations. + * \param b The blue source color value multiplied into blit operations. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \sa SDL_GetSurfaceColorMod() */ 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 - * - * \param surface The surface to query - * \param r A pointer filled in with the source red color value - * \param g A pointer filled in with the source green color value - * \param b A pointer filled in with the source blue color value - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_SetSurfaceColorMod() + * \brief Get the additional color value used in blit operations. + * + * \param surface The surface to query. + * \param r A pointer filled in with the source red color value. + * \param g A pointer filled in with the source green color value. + * \param b A pointer filled in with the source blue color value. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \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 - * - * \param surface The surface to update - * \param alpha The source alpha value multiplied into blit operations. - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_GetSurfaceAlphaMod() + * \brief Set an additional alpha value used in blit operations. + * + * \param surface The surface to update. + * \param alpha The source alpha value multiplied into blit operations. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \sa SDL_GetSurfaceAlphaMod() */ extern DECLSPEC int SDLCALL SDL_SetSurfaceAlphaMod(SDL_Surface * surface, Uint8 alpha); /** - * \brief Get the additional alpha value used in blit operations - * - * \param surface The surface to query - * \param alpha A pointer filled in with the source alpha value - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_SetSurfaceAlphaMod() + * \brief Get the additional alpha value used in blit operations. + * + * \param surface The surface to query. + * \param alpha A pointer filled in with the source alpha value. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \sa SDL_SetSurfaceAlphaMod() */ extern DECLSPEC int SDLCALL SDL_GetSurfaceAlphaMod(SDL_Surface * surface, Uint8 * alpha); /** - * \brief Set the blend mode used for blit operations - * - * \param surface The surface to update - * \param blendMode SDL_TextureBlendMode to use for blit blending - * - * \return 0 on success, or -1 if the parameters are not valid - * - * \sa SDL_GetSurfaceBlendMode() + * \brief Set the blend mode used for blit operations. + * + * \param surface The surface to update. + * \param blendMode ::SDL_BlendMode to use for blit blending. + * + * \return 0 on success, or -1 if the parameters are not valid. + * + * \sa SDL_GetSurfaceBlendMode() */ extern DECLSPEC int SDLCALL SDL_SetSurfaceBlendMode(SDL_Surface * surface, int blendMode); /** - * \brief 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 - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_SetSurfaceBlendMode() + * \brief 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. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \sa SDL_SetSurfaceBlendMode() */ extern DECLSPEC int SDLCALL SDL_GetSurfaceBlendMode(SDL_Surface * surface, int *blendMode); /** - * \brief Set the scale mode used for blit operations - * - * \param surface The surface to update - * \param scaleMode SDL_TextureScaleMode to use for blit scaling - * - * \return 0 on success, or -1 if the surface is not valid or the scale mode is not supported - * - * \note If the scale mode is not supported, the closest supported mode is chosen. Currently only SDL_TEXTURESCALEMODE_FAST is supported on surfaces. - * - * \sa SDL_GetSurfaceScaleMode() + * \brief Set the scale mode used for blit operations. + * + * \param surface The surface to update. + * \param scaleMode ::SDL_TextureScaleMode to use for blit scaling. + * + * \return 0 on success, or -1 if the surface is not valid or the scale mode is + * not supported. + * + * \note If the scale mode is not supported, the closest supported mode is + * chosen. Currently only ::SDL_TEXTURESCALEMODE_FAST is supported on + * surfaces. + * + * \sa SDL_GetSurfaceScaleMode() */ extern DECLSPEC int SDLCALL SDL_SetSurfaceScaleMode(SDL_Surface * surface, int scaleMode); /** - * \brief Get the scale mode used for blit operations - * - * \param surface The surface to query - * \param scaleMode A pointer filled in with the current scale mode - * - * \return 0 on success, or -1 if the surface is not valid - * - * \sa SDL_SetSurfaceScaleMode() + * \brief Get the scale mode used for blit operations. + * + * \param surface The surface to query. + * \param scaleMode A pointer filled in with the current scale mode. + * + * \return 0 on success, or -1 if the surface is not valid. + * + * \sa SDL_SetSurfaceScaleMode() */ extern DECLSPEC int SDLCALL SDL_GetSurfaceScaleMode(SDL_Surface * surface, int *scaleMode); /** - * Sets the clipping rectangle for the destination surface in a blit. - * - * If the clip rectangle is NULL, clipping will be disabled. - * 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. + * Sets the clipping rectangle for the destination surface in a blit. + * + * If the clip rectangle is NULL, clipping will be disabled. + * + * 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. */ 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. - * 'rect' must be a pointer to a valid rectangle which will be filled - * with the correct values. + * Gets the clipping rectangle for the destination surface in a blit. + * + * \c rect must be a pointer to a valid rectangle which will be filled + * with the correct values. */ extern DECLSPEC void SDLCALL SDL_GetClipRect(SDL_Surface * surface, SDL_Rect * rect); /** - * 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. - * - * The '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 internally by SDL_DisplayFormat(). + * 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. + * + * 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 internally by SDL_DisplayFormat(). */ extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface (SDL_Surface * src, SDL_PixelFormat * fmt, Uint32 flags); /** - * This function draws a point with 'color' - * The color should be a pixel of the format used by the surface, and - * can be generated by the SDL_MapRGB() function. - * \return This function returns 0 on success, or -1 on error. + * Draws a point with \c color. + * + * The color should be a pixel of the format used by the surface, and + * can be generated by the SDL_MapRGB() function. + * + * \return 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_DrawPoint (SDL_Surface * dst, int x, int y, Uint32 color); /** - * This function blends a point with an RGBA value - * The color should be a pixel of the format used by the surface, and - * can be generated by the SDL_MapRGB() function. - * \return This function returns 0 on success, or -1 on error. + * Blends a point with an RGBA value. + * + * The color should be a pixel of the format used by the surface, and + * can be generated by the SDL_MapRGB() function. + * + * \return 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_BlendPoint (SDL_Surface * dst, int x, int y, int blendMode, Uint8 r, Uint8 g, Uint8 b, Uint8 a); /** - * This function draws a line with 'color' - * The color should be a pixel of the format used by the surface, and - * can be generated by the SDL_MapRGB() function. - * \return This function returns 0 on success, or -1 on error. + * Draws a line with \c color. + * + * The color should be a pixel of the format used by the surface, and + * can be generated by the SDL_MapRGB() function. + * + * \return 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_DrawLine (SDL_Surface * dst, int x1, int y1, int x2, int y2, Uint32 color); /** - * This function blends an RGBA value along a line - * \return This function returns 0 on success, or -1 on error. + * Blends an RGBA value along a line. + * + * \return 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_BlendLine (SDL_Surface * dst, int x1, int y1, int x2, int y2, int blendMode, Uint8 r, Uint8 g, Uint8 b, Uint8 a); /** - * This function performs a fast fill of the given rectangle with 'color' - * The given rectangle is clipped to the destination surface clip area - * and the final fill rectangle is saved in the passed in pointer. - * If 'dstrect' is NULL, the whole surface will be filled with 'color' - * The color should be a pixel of the format used by the surface, and - * can be generated by the SDL_MapRGB() function. - * \return This function returns 0 on success, or -1 on error. + * Performs a fast fill of the given rectangle with \c color. + * + * The given rectangle is clipped to the destination surface clip area + * and the final fill rectangle is saved in the passed in pointer. + * + * If \c dstrect is NULL, the whole surface will be filled with \c color. + * + * The color should be a pixel of the format used by the surface, and + * can be generated by the SDL_MapRGB() function. + * + * \return 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_FillRect (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color); /** - * This function blends an RGBA value into the given rectangle. - * The given rectangle is clipped to the destination surface clip area - * and the final fill rectangle is saved in the passed in pointer. - * If 'dstrect' is NULL, the whole surface will be filled with 'color' - * \return This function returns 0 on success, or -1 on error. + * Blends an RGBA value into the given rectangle. + * + * The given rectangle is clipped to the destination surface clip area + * and the final fill rectangle is saved in the passed in pointer. + * + * If \c dstrect is NULL, the whole surface will be filled with \c color. + * + * \return This function returns 0 on success, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_BlendRect (SDL_Surface * dst, SDL_Rect * dstrect, int blendMode, Uint8 r, Uint8 g, Uint8 b, Uint8 a); /** - * This performs a fast blit from the source surface to the destination - * surface. It assumes that the source and destination rectangles are - * the same size. If either 'srcrect' or 'dstrect' are NULL, the entire - * surface (src or dst) is copied. The final blit rectangles are saved - * in 'srcrect' and 'dstrect' after all clipping is performed. - * If the blit is successful, it returns 0, otherwise it returns -1. + * 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. * - * The blit function should not be called on a locked surface. - * - * The blit semantics for surfaces with and without alpha and colorkey - * are defined as follows: + * The blit function should not be called on a locked surface. * - * RGBA->RGB: - * SDL_SRCALPHA set: - * alpha-blend (using alpha-channel). - * SDL_SRCCOLORKEY ignored. - * SDL_SRCALPHA not set: - * copy RGB. - * if SDL_SRCCOLORKEY set, only copy the pixels matching the - * RGB values of the source colour key, ignoring alpha in the - * comparison. - * - * RGB->RGBA: - * SDL_SRCALPHA set: - * alpha-blend (using the source per-surface alpha value); - * set destination alpha to opaque. - * SDL_SRCALPHA not set: - * copy RGB, set destination alpha to source per-surface alpha value. - * both: - * if SDL_SRCCOLORKEY set, only copy the pixels matching the - * source colour key. - * - * RGBA->RGBA: - * SDL_SRCALPHA set: - * alpha-blend (using the source alpha channel) the RGB values; - * leave destination alpha untouched. [Note: is this correct?] - * SDL_SRCCOLORKEY ignored. - * SDL_SRCALPHA not set: - * copy all of RGBA to the destination. - * if SDL_SRCCOLORKEY set, only copy the pixels matching the - * RGB values of the source colour key, ignoring alpha in the - * comparison. - * - * RGB->RGB: - * SDL_SRCALPHA set: - * alpha-blend (using the source per-surface alpha value). - * SDL_SRCALPHA not set: - * copy RGB. - * both: - * if SDL_SRCCOLORKEY set, only copy the pixels matching the - * source colour key. - * - * If either of the surfaces were in video memory, and the blit returns -2, - * the video memory was lost, so it should be reloaded with artwork and - * re-blitted: - * @code - * while ( SDL_BlitSurface(image, imgrect, screen, dstrect) == -2 ) { - * while ( SDL_LockSurface(image) < 0 ) - * Sleep(10); - * -- Write image pixels to image->pixels -- - * SDL_UnlockSurface(image); - * } - * @endcode - * - * This happens under DirectX 5.0 when the system switches away from your - * fullscreen application. The lock will also fail until you have access - * to the video memory again. - * - * You should call SDL_BlitSurface() unless you know exactly how SDL - * blitting works internally and how to use the other blit functions. + * The blit semantics for surfaces with and without alpha and colorkey + * are defined as follows: + * \verbatim + RGBA->RGB: + SDL_SRCALPHA set: + alpha-blend (using alpha-channel). + SDL_SRCCOLORKEY ignored. + SDL_SRCALPHA not set: + copy RGB. + if SDL_SRCCOLORKEY set, only copy the pixels matching the + RGB values of the source colour key, ignoring alpha in the + comparison. + + RGB->RGBA: + SDL_SRCALPHA set: + alpha-blend (using the source per-surface alpha value); + set destination alpha to opaque. + SDL_SRCALPHA not set: + copy RGB, set destination alpha to source per-surface alpha value. + both: + if SDL_SRCCOLORKEY set, only copy the pixels matching the + source colour key. + + RGBA->RGBA: + SDL_SRCALPHA set: + alpha-blend (using the source alpha channel) the RGB values; + leave destination alpha untouched. [Note: is this correct?] + SDL_SRCCOLORKEY ignored. + SDL_SRCALPHA not set: + copy all of RGBA to the destination. + if SDL_SRCCOLORKEY set, only copy the pixels matching the + RGB values of the source colour key, ignoring alpha in the + comparison. + + RGB->RGB: + SDL_SRCALPHA set: + alpha-blend (using the source per-surface alpha value). + SDL_SRCALPHA not set: + copy RGB. + both: + if SDL_SRCCOLORKEY set, only copy the pixels matching the + source colour key. + \endverbatim + * + * If either of the surfaces were in video memory, and the blit returns -2, + * the video memory was lost, so it should be reloaded with artwork and + * re-blitted: + * @code + * while ( SDL_BlitSurface(image, imgrect, screen, dstrect) == -2 ) { + * while ( SDL_LockSurface(image) < 0 ) + * Sleep(10); + * -- Write image pixels to image->pixels -- + * SDL_UnlockSurface(image); + * } + * @endcode + * + * This happens under DirectX 5.0 when the system switches away from your + * fullscreen application. The lock will also fail until you have access + * to the video memory again. + * + * You should call SDL_BlitSurface() unless you know exactly how SDL + * 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 +/** + * This is the public blit function, SDL_BlitSurface(), and it performs * rectangle validation and clipping before passing it to SDL_LowerBlit() */ extern DECLSPEC int SDLCALL SDL_UpperBlit (SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect); -/** This is a semi-private blit function and it performs low-level surface +/** + * This is a semi-private blit function and it performs low-level surface * blitting only. */ extern DECLSPEC int SDLCALL SDL_LowerBlit @@ -505,9 +553,10 @@ SDL_Surface * dst, SDL_Rect * dstrect); /** - * \brief Perform a fast, low quality, stretch blit between two surfaces of the same pixel format. - * - * \note This function uses a static buffer, and is not thread-safe. + * \brief Perform a fast, low quality, stretch blit between two surfaces of the + * same pixel format. + * + * \note This function uses a static buffer, and is not thread-safe. */ extern DECLSPEC int SDLCALL SDL_SoftStretch(SDL_Surface * src, const SDL_Rect * srcrect,