gd.h

来自「Linux/Unix下的绘图函数库（Graphic Drawing Librar」· C头文件 代码 · 共 796 行 · 第 1/3 页

/* These read the first frame only */
BGD_DECLARE(gdImagePtr) gdImageCreateFromGif (FILE * fd);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGifCtx (gdIOCtxPtr in);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGifPtr (int size, void *data);
BGD_DECLARE(gdImagePtr) gdImageCreateFromWBMP (FILE * inFile);
BGD_DECLARE(gdImagePtr) gdImageCreateFromWBMPCtx (gdIOCtx * infile);
BGD_DECLARE(gdImagePtr) gdImageCreateFromWBMPPtr (int size, void *data);
BGD_DECLARE(gdImagePtr) gdImageCreateFromJpeg (FILE * infile);
BGD_DECLARE(gdImagePtr) gdImageCreateFromJpegCtx (gdIOCtx * infile);
BGD_DECLARE(gdImagePtr) gdImageCreateFromJpegPtr (int size, void *data);

/* A custom data source. */
/* The source function must return -1 on error, otherwise the number
        of bytes fetched. 0 is EOF, not an error! */
/* context will be passed to your source function. */

  typedef struct
  {
    int (*source) (void *context, char *buffer, int len);
    void *context;
  }
  gdSource, *gdSourcePtr;

   /* Deprecated in favor of gdImageCreateFromPngCtx */
BGD_DECLARE(gdImagePtr) gdImageCreateFromPngSource (gdSourcePtr in);

BGD_DECLARE(gdImagePtr) gdImageCreateFromGd (FILE * in);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGdCtx (gdIOCtxPtr in);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGdPtr (int size, void *data);

BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2 (FILE * in);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2Ctx (gdIOCtxPtr in);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2Ptr (int size, void *data);

BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2Part (FILE * in, int srcx, int srcy, int w,
				       int h);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2PartCtx (gdIOCtxPtr in, int srcx, int srcy,
					  int w, int h);
BGD_DECLARE(gdImagePtr) gdImageCreateFromGd2PartPtr (int size, void *data, int srcx, int srcy,
					  int w, int h);
  /* 2.0.10: prototype was missing */
BGD_DECLARE(gdImagePtr) gdImageCreateFromXbm (FILE * in);

  /* NOTE: filename, not FILE */
BGD_DECLARE(gdImagePtr) gdImageCreateFromXpm (char *filename);

BGD_DECLARE(void) gdImageDestroy (gdImagePtr im);

/* Replaces or blends with the background depending on the
	most recent call to gdImageAlphaBlending and the
	alpha channel value of 'color'; default is to overwrite. 
	Tiling and line styling are also implemented
	here. All other gd drawing functions pass through this call, 
	allowing for many useful effects. */

BGD_DECLARE(void) gdImageSetPixel (gdImagePtr im, int x, int y, int color);
/* FreeType 2 text output with hook to extra flags */

BGD_DECLARE(int) gdImageGetPixel (gdImagePtr im, int x, int y);
BGD_DECLARE(int) gdImageGetTrueColorPixel (gdImagePtr im, int x, int y);

BGD_DECLARE(void) gdImageAABlend (gdImagePtr im);

BGD_DECLARE(void) gdImageLine (gdImagePtr im, int x1, int y1, int x2, int y2, int color);

/* For backwards compatibility only. Use gdImageSetStyle()
	for much more flexible line drawing. */
BGD_DECLARE(void) gdImageDashedLine (gdImagePtr im, int x1, int y1, int x2, int y2,
			  int color);
/* Corners specified (not width and height). Upper left first, lower right
 	second. */
BGD_DECLARE(void) gdImageRectangle (gdImagePtr im, int x1, int y1, int x2, int y2,
			 int color);
/* Solid bar. Upper left corner first, lower right corner second. */
BGD_DECLARE(void) gdImageFilledRectangle (gdImagePtr im, int x1, int y1, int x2, int y2,
			       int color);
BGD_DECLARE(void) gdImageSetClip(gdImagePtr im, int x1, int y1, int x2, int y2);
BGD_DECLARE(void) gdImageGetClip(gdImagePtr im, int *x1P, int *y1P, int *x2P, int *y2P);
BGD_DECLARE(int) gdImageBoundsSafe (gdImagePtr im, int x, int y);
BGD_DECLARE(void) gdImageChar (gdImagePtr im, gdFontPtr f, int x, int y, int c,
		    int color);
BGD_DECLARE(void) gdImageCharUp (gdImagePtr im, gdFontPtr f, int x, int y, int c,
		      int color);
BGD_DECLARE(void) gdImageString (gdImagePtr im, gdFontPtr f, int x, int y,
		      unsigned char *s, int color);
BGD_DECLARE(void) gdImageStringUp (gdImagePtr im, gdFontPtr f, int x, int y,
			unsigned char *s, int color);
BGD_DECLARE(void) gdImageString16 (gdImagePtr im, gdFontPtr f, int x, int y,
			unsigned short *s, int color);
BGD_DECLARE(void) gdImageStringUp16 (gdImagePtr im, gdFontPtr f, int x, int y,
			  unsigned short *s, int color);

/* 2.0.16: for thread-safe use of gdImageStringFT and friends,
  call this before allowing any thread to call gdImageStringFT. 
  Otherwise it is invoked by the first thread to invoke
  gdImageStringFT, with a very small but real risk of a race condition. 
  Return 0 on success, nonzero on failure to initialize freetype. */
BGD_DECLARE(int) gdFontCacheSetup (void);

/* Optional: clean up after application is done using fonts in 
BGD_DECLARE( ) gdImageStringFT(). */
BGD_DECLARE(void) gdFontCacheShutdown (void);
/* 2.0.20: for backwards compatibility. A few applications did start calling
 this function when it first appeared although it was never documented. 
 Simply invokes gdFontCacheShutdown. */
BGD_DECLARE(void) gdFreeFontCache (void);

/* Calls gdImageStringFT. Provided for backwards compatibility only. */
BGD_DECLARE(char *) gdImageStringTTF (gdImage * im, int *brect, int fg, char *fontlist,
			  double ptsize, double angle, int x, int y,
			  char *string);

/* FreeType 2 text output */
BGD_DECLARE(char *) gdImageStringFT (gdImage * im, int *brect, int fg, char *fontlist,
			 double ptsize, double angle, int x, int y,
			 char *string);

/* 2.0.5: provides an extensible way to pass additional parameters.
	Thanks to Wez Furlong, sorry for the delay. */

  typedef struct
  {
    int flags;			/* Logical OR of gdFTEX_ values */
    double linespacing;		/* fine tune line spacing for '\n' */
    int charmap;		/* TBB: 2.0.12: may be gdFTEX_Unicode,
				   gdFTEX_Shift_JIS, or gdFTEX_Big5;
				   when not specified, maps are searched
				   for in the above order. */
    int hdpi;                   /* if (flags & gdFTEX_RESOLUTION) */
    int vdpi;			/* if (flags & gdFTEX_RESOLUTION) */
    char *xshow;	/* if (flags & gdFTEX_XSHOW)
			   then, on return, xshow is a malloc'ed
			   string contining xshow position data for
			   the last string.

			   NB. The caller is responsible for gdFree'ing
			   the xshow string. 
			 */
    char *fontpath;	/* if (flags & gdFTEX_RETURNFONTPATHNAME)
                           then, on return, fontpath is a malloc'ed
                           string containing the actual font file path name
                           used, which can be interesting when fontconfig
                           is in use. 

                           The caller is responsible for gdFree'ing the
                           fontpath string.
			*/

  }
  gdFTStringExtra, *gdFTStringExtraPtr;

#define gdFTEX_LINESPACE 1
#define gdFTEX_CHARMAP 2
#define gdFTEX_RESOLUTION 4
#define gdFTEX_DISABLE_KERNING 8
#define gdFTEX_XSHOW 16
/* The default unless gdFTUseFontConfig(1); has been called:
  fontlist is a full or partial font file pathname or list thereof 
  (i.e. just like before 2.0.29) */
#define gdFTEX_FONTPATHNAME 32
/* Necessary to use fontconfig patterns instead of font pathnames
  as the fontlist argument, unless gdFTUseFontConfig(1); has 
  been called. New in 2.0.29 */
#define gdFTEX_FONTCONFIG 64
/* Sometimes interesting when fontconfig is used: the fontpath
  element of the structure above will contain a gdMalloc'd string
  copy of the actual font file pathname used, if this flag is set 
   when the call is made */
#define gdFTEX_RETURNFONTPATHNAME 128

/* If flag is nonzero, the fontlist parameter to gdImageStringFT 
  and gdImageStringFTEx shall be assumed to be a fontconfig font pattern
  if fontconfig was compiled into gd. This function returns zero
  if fontconfig is not available, nonzero otherwise. */
BGD_DECLARE(int) gdFTUseFontConfig(int flag);

/* These are NOT flags; set one in 'charmap' if you set the
	gdFTEX_CHARMAP bit in 'flags'. */
#define gdFTEX_Unicode 0
#define gdFTEX_Shift_JIS 1
#define gdFTEX_Big5 2

BGD_DECLARE(char *) gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist,
			   double ptsize, double angle, int x, int y,
			   char *string, gdFTStringExtraPtr strex);

/* Point type for use in polygon drawing. */
  typedef struct
  {
    int x, y;
  }
  gdPoint, *gdPointPtr;

BGD_DECLARE(void) gdImagePolygon (gdImagePtr im, gdPointPtr p, int n, int c);
BGD_DECLARE(void) gdImageOpenPolygon (gdImagePtr im, gdPointPtr p, int n, int c);
BGD_DECLARE(void) gdImageFilledPolygon (gdImagePtr im, gdPointPtr p, int n, int c);

/* These functions still work with truecolor images, 
	for which they never return error. */
BGD_DECLARE(int) gdImageColorAllocate (gdImagePtr im, int r, int g, int b);
/* gd 2.0: palette entries with non-opaque transparency are permitted. */
BGD_DECLARE(int) gdImageColorAllocateAlpha (gdImagePtr im, int r, int g, int b, int a);
/* Assumes opaque is the preferred alpha channel value */
BGD_DECLARE(int) gdImageColorClosest (gdImagePtr im, int r, int g, int b);
/* Closest match taking all four parameters into account.
	A slightly different color with the same transparency
	beats the exact same color with radically different
	transparency */
BGD_DECLARE(int) gdImageColorClosestAlpha (gdImagePtr im, int r, int g, int b, int a);
/* An alternate method */
BGD_DECLARE(int) gdImageColorClosestHWB (gdImagePtr im, int r, int g, int b);
/* Returns exact, 100% opaque matches only */
BGD_DECLARE(int) gdImageColorExact (gdImagePtr im, int r, int g, int b);
/* Returns an exact match only, including alpha */
BGD_DECLARE(int) gdImageColorExactAlpha (gdImagePtr im, int r, int g, int b, int a);
/* Opaque only */
BGD_DECLARE(int) gdImageColorResolve (gdImagePtr im, int r, int g, int b);
/* Based on gdImageColorExactAlpha and gdImageColorClosestAlpha */
BGD_DECLARE(int) gdImageColorResolveAlpha (gdImagePtr im, int r, int g, int b, int a);

/* A simpler way to obtain an opaque truecolor value for drawing on a
	truecolor image. Not for use with palette images! */

#define gdTrueColor(r, g, b) (((r) << 16) + \
	((g) << 8) + \
	(b))

/* Returns a truecolor value with an alpha channel component.
	gdAlphaMax (127, **NOT 255**) is transparent, 0 is completely
	opaque. */

#define gdTrueColorAlpha(r, g, b, a) (((a) << 24) + \
	((r) << 16) + \
	((g) << 8) + \
	(b))

BGD_DECLARE(void) gdImageColorDeallocate (gdImagePtr im, int color);

/* Converts a truecolor image to a palette-based image,
	using a high-quality two-pass quantization routine
	which attempts to preserve alpha channel information
	as well as R/G/B color information when creating
	a palette. If ditherFlag is set, the image will be
	dithered to approximate colors better, at the expense
	of some obvious "speckling." colorsWanted can be
	anything up to 256. If the original source image
	includes photographic information or anything that
	came out of a JPEG, 256 is strongly recommended.

	Better yet, don't use these function -- write real
	truecolor PNGs and JPEGs. The disk space gain of
        conversion to palette is not great (for small images
        it can be negative) and the quality loss is ugly. 

	DIFFERENCES: gdImageCreatePaletteFromTrueColor creates and
	returns a new image. gdImageTrueColorToPalette modifies 
	an existing image, and the truecolor pixels are discarded. */

BGD_DECLARE(gdImagePtr) gdImageCreatePaletteFromTrueColor (gdImagePtr im, int ditherFlag,
				  int colorsWanted);

BGD_DECLARE(void) gdImageTrueColorToPalette (gdImagePtr im, int ditherFlag,
				  int colorsWanted);

/* Specifies a color index (if a palette image) or an