gd.c

PHP v6.0 For Linux 运行环境：Win9X/ WinME/ WinNT/ Win2K/ WinXP

#include <stdio.h>
#include <math.h>
#include <string.h>
#include <stdlib.h>
#include "gd.h"
#include "gdhelpers.h"

#include "php.h"

#ifdef _MSC_VER
# if _MSC_VER >= 1300
/* in MSVC.NET these are available but only for __cplusplus and not _MSC_EXTENSIONS */
#  if !defined(_MSC_EXTENSIONS) && defined(__cplusplus)
#   define HAVE_FABSF 1
extern float fabsf(float x);
#   define HAVE_FLOORF 1
extern float floorf(float x);
#  endif /*MSVC.NET */
# endif /* MSC */
#endif
#ifndef HAVE_FABSF
# define HAVE_FABSF 0
#endif
#ifndef HAVE_FLOORF
# define HAVE_FLOORF 0
#endif
#if HAVE_FABSF == 0
/* float fabsf(float x); */
# define fabsf(x) ((float)(fabs(x)))
#endif
#if HAVE_FLOORF == 0
/* float floorf(float x);*/
#define floorf(x) ((float)(floor(x)))
#endif

#ifdef _OSD_POSIX		/* BS2000 uses the EBCDIC char set instead of ASCII */
#define CHARSET_EBCDIC
#define __attribute__(any)	/*nothing */
#endif
/*_OSD_POSIX*/

#ifndef CHARSET_EBCDIC
#define ASC(ch)  ch
#else /*CHARSET_EBCDIC */
#define ASC(ch) gd_toascii[(unsigned char)ch]
static const unsigned char gd_toascii[256] =
{
/*00 */ 0x00, 0x01, 0x02, 0x03, 0x85, 0x09, 0x86, 0x7f,
  0x87, 0x8d, 0x8e, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,	/*................ */
/*10 */ 0x10, 0x11, 0x12, 0x13, 0x8f, 0x0a, 0x08, 0x97,
  0x18, 0x19, 0x9c, 0x9d, 0x1c, 0x1d, 0x1e, 0x1f,	/*................ */
/*20 */ 0x80, 0x81, 0x82, 0x83, 0x84, 0x92, 0x17, 0x1b,
  0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x05, 0x06, 0x07,	/*................ */
/*30 */ 0x90, 0x91, 0x16, 0x93, 0x94, 0x95, 0x96, 0x04,
  0x98, 0x99, 0x9a, 0x9b, 0x14, 0x15, 0x9e, 0x1a,	/*................ */
/*40 */ 0x20, 0xa0, 0xe2, 0xe4, 0xe0, 0xe1, 0xe3, 0xe5,
  0xe7, 0xf1, 0x60, 0x2e, 0x3c, 0x28, 0x2b, 0x7c,	/* .........`.<(+| */
/*50 */ 0x26, 0xe9, 0xea, 0xeb, 0xe8, 0xed, 0xee, 0xef,
  0xec, 0xdf, 0x21, 0x24, 0x2a, 0x29, 0x3b, 0x9f,	/*&.........!$*);. */
/*60 */ 0x2d, 0x2f, 0xc2, 0xc4, 0xc0, 0xc1, 0xc3, 0xc5,
  0xc7, 0xd1, 0x5e, 0x2c, 0x25, 0x5f, 0x3e, 0x3f,
/*-/........^,%_>?*/
/*70 */ 0xf8, 0xc9, 0xca, 0xcb, 0xc8, 0xcd, 0xce, 0xcf,
  0xcc, 0xa8, 0x3a, 0x23, 0x40, 0x27, 0x3d, 0x22,	/*..........:#@'=" */
/*80 */ 0xd8, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
  0x68, 0x69, 0xab, 0xbb, 0xf0, 0xfd, 0xfe, 0xb1,	/*.abcdefghi...... */
/*90 */ 0xb0, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70,
  0x71, 0x72, 0xaa, 0xba, 0xe6, 0xb8, 0xc6, 0xa4,	/*.jklmnopqr...... */
/*a0 */ 0xb5, 0xaf, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
  0x79, 0x7a, 0xa1, 0xbf, 0xd0, 0xdd, 0xde, 0xae,	/*..stuvwxyz...... */
/*b0 */ 0xa2, 0xa3, 0xa5, 0xb7, 0xa9, 0xa7, 0xb6, 0xbc,
  0xbd, 0xbe, 0xac, 0x5b, 0x5c, 0x5d, 0xb4, 0xd7,	/*...........[\].. */
/*c0 */ 0xf9, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
  0x48, 0x49, 0xad, 0xf4, 0xf6, 0xf2, 0xf3, 0xf5,	/*.ABCDEFGHI...... */
/*d0 */ 0xa6, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50,
  0x51, 0x52, 0xb9, 0xfb, 0xfc, 0xdb, 0xfa, 0xff,	/*.JKLMNOPQR...... */
/*e0 */ 0xd9, 0xf7, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
  0x59, 0x5a, 0xb2, 0xd4, 0xd6, 0xd2, 0xd3, 0xd5,	/*..STUVWXYZ...... */
/*f0 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
  0x38, 0x39, 0xb3, 0x7b, 0xdc, 0x7d, 0xda, 0x7e	/*0123456789.{.}.~ */
};
#endif /*CHARSET_EBCDIC */

/* 2.0.10: cast instead of floor() yields 35% performance improvement. Thanks to John Buckman. */
#define floor_cast(exp) ((long) exp)

extern int gdCosT[];
extern int gdSinT[];

static void gdImageBrushApply(gdImagePtr im, int x, int y);
static void gdImageTileApply(gdImagePtr im, int x, int y);
static void gdImageAntiAliasedApply(gdImagePtr im, int x, int y);
static int gdLayerOverlay(int dst, int src);
static int gdAlphaOverlayColor(int src, int dst, int max);
int gdImageGetTrueColorPixel(gdImagePtr im, int x, int y);

void php_gd_error_ex(int type, const char *format, ...)
{
	va_list args;

	TSRMLS_FETCH();

	va_start(args, format);
	php_verror(NULL, "", type, format, args TSRMLS_CC);
	va_end(args);
}

void php_gd_error(const char *format, ...)
{
	va_list args;

	TSRMLS_FETCH();

	va_start(args, format);
	php_verror(NULL, "", E_WARNING, format, args TSRMLS_CC);
	va_end(args);
}

gdImagePtr gdImageCreate (int sx, int sy)
{
	int i;
	gdImagePtr im;
	im = (gdImage *) gdMalloc(sizeof(gdImage));
	memset(im, 0, sizeof(gdImage));
	/* Row-major ever since gd 1.3 */
	im->pixels = (unsigned char **) gdMalloc(sizeof(unsigned char *) * sy);
	im->AA_opacity = (unsigned char **) gdMalloc(sizeof(unsigned char *) * sy);
	im->polyInts = 0;
	im->polyAllocated = 0;
	im->brush = 0;
	im->tile = 0;
	im->style = 0;
	for (i = 0; i < sy; i++) {
		/* Row-major ever since gd 1.3 */
		im->pixels[i] = (unsigned char *) gdCalloc(sx, sizeof(unsigned char));
		im->AA_opacity[i] = (unsigned char *) gdCalloc(sx, sizeof(unsigned char));
	}
	im->sx = sx;
	im->sy = sy;
	im->colorsTotal = 0;
	im->transparent = (-1);
	im->interlace = 0;
	im->thick = 1;
	im->AA = 0;
	im->AA_polygon = 0;
	for (i = 0; i < gdMaxColors; i++) {
		im->open[i] = 1;
		im->red[i] = 0;
		im->green[i] = 0;
		im->blue[i] = 0;
	}
	im->trueColor = 0;
	im->tpixels = 0;
	im->cx1 = 0;
	im->cy1 = 0;
	im->cx2 = im->sx - 1;
	im->cy2 = im->sy - 1;
	return im;
}

gdImagePtr gdImageCreateTrueColor (int sx, int sy)
{
	int i;
	gdImagePtr im;
	im = (gdImage *) gdMalloc(sizeof(gdImage));
	memset(im, 0, sizeof(gdImage));
	im->tpixels = (int **) gdMalloc(sizeof(int *) * sy);
	im->AA_opacity = (unsigned char **) gdMalloc(sizeof(unsigned char *) * sy);
	im->polyInts = 0;
	im->polyAllocated = 0;
	im->brush = 0;
	im->tile = 0;
	im->style = 0;
	for (i = 0; i < sy; i++) {
		im->tpixels[i] = (int *) gdCalloc(sx, sizeof(int));
		im->AA_opacity[i] = (unsigned char *) gdCalloc(sx, sizeof(unsigned char));
	}
	im->sx = sx;
	im->sy = sy;
	im->transparent = (-1);
	im->interlace = 0;
	im->trueColor = 1;
	/* 2.0.2: alpha blending is now on by default, and saving of alpha is
	 * off by default. This allows font antialiasing to work as expected
	 * on the first try in JPEGs -- quite important -- and also allows
	 * for smaller PNGs when saving of alpha channel is not really
	 * desired, which it usually isn't!
	 */
	im->saveAlphaFlag = 0;
	im->alphaBlendingFlag = 1;
	im->thick = 1;
	im->AA = 0;
	im->AA_polygon = 0;
	im->cx1 = 0;
	im->cy1 = 0;
	im->cx2 = im->sx - 1;
	im->cy2 = im->sy - 1;
	return im;
}

void gdImageDestroy (gdImagePtr im)
{
	int i;
	if (im->pixels) {
		for (i = 0; i < im->sy; i++) {
			gdFree(im->pixels[i]);
		}
		gdFree(im->pixels);
	}
	if (im->tpixels) {
		for (i = 0; i < im->sy; i++) {
			gdFree(im->tpixels[i]);
		}
		gdFree(im->tpixels);
	}
	if (im->AA_opacity) {
		for (i = 0; i < im->sy; i++) {
			gdFree(im->AA_opacity[i]);
		}
		gdFree(im->AA_opacity);
	}
	if (im->polyInts) {
		gdFree(im->polyInts);
	}
	if (im->style) {
		gdFree(im->style);
	}
	gdFree(im);
}

int gdImageColorClosest (gdImagePtr im, int r, int g, int b)
{
	return gdImageColorClosestAlpha (im, r, g, b, gdAlphaOpaque);
}

int gdImageColorClosestAlpha (gdImagePtr im, int r, int g, int b, int a)
{
	int i;
	long rd, gd, bd, ad;
	int ct = (-1);
	int first = 1;
	long mindist = 0;

	if (im->trueColor) {
		return gdTrueColorAlpha(r, g, b, a);
	}
	for (i = 0; i < im->colorsTotal; i++) {
		long dist;
		if (im->open[i]) {
			continue;
		}
		rd = im->red[i] - r;
		gd = im->green[i] - g;
		bd = im->blue[i] - b;
		/* gd 2.02: whoops, was - b (thanks to David Marwood) */
		ad = im->alpha[i] - a;
		dist = rd * rd + gd * gd + bd * bd + ad * ad;
		if (first || (dist < mindist)) {
			mindist = dist;
			ct = i;
			first = 0;
		}
	}
	return ct;
}

/* This code is taken from http://www.acm.org/jgt/papers/SmithLyons96/hwb_rgb.html, an article
 * on colour conversion to/from RBG and HWB colour systems.
 * It has been modified to return the converted value as a * parameter.
 */

#define RETURN_HWB(h, w, b) {HWB->H = h; HWB->W = w; HWB->B = b; return HWB;}
#define RETURN_RGB(r, g, b) {RGB->R = r; RGB->G = g; RGB->B = b; return RGB;}
#define HWB_UNDEFINED -1
#define SETUP_RGB(s, r, g, b) {s.R = r/255.0f; s.G = g/255.0f; s.B = b/255.0f;}

#ifndef MIN
#define MIN(a,b) ((a)<(b)?(a):(b))
#endif
#define MIN3(a,b,c) ((a)<(b)?(MIN(a,c)):(MIN(b,c)))
#ifndef MAX
#define MAX(a,b) ((a)<(b)?(b):(a))
#endif
#define MAX3(a,b,c) ((a)<(b)?(MAX(b,c)):(MAX(a,c)))


/*
 * Theoretically, hue 0 (pure red) is identical to hue 6 in these transforms. Pure
 * red always maps to 6 in this implementation. Therefore UNDEFINED can be
 * defined as 0 in situations where only unsigned numbers are desired.
 */
typedef struct
{
	float R, G, B;
}
RGBType;
typedef struct
{
	float H, W, B;
}
HWBType;

static HWBType * RGB_to_HWB (RGBType RGB, HWBType * HWB)
{
	/*
	 * RGB are each on [0, 1]. W and B are returned on [0, 1] and H is
	 * returned on [0, 6]. Exception: H is returned UNDEFINED if W == 1 - B.
	 */

	float R = RGB.R, G = RGB.G, B = RGB.B, w, v, b, f;
	int i;

	w = MIN3 (R, G, B);
	v = MAX3 (R, G, B);
	b = 1 - v;
	if (v == w) {
		RETURN_HWB(HWB_UNDEFINED, w, b);
	}
	f = (R == w) ? G - B : ((G == w) ? B - R : R - G);
	i = (R == w) ? 3 : ((G == w) ? 5 : 1);

	RETURN_HWB(i - f / (v - w), w, b);
}

static float HWB_Diff (int r1, int g1, int b1, int r2, int g2, int b2)
{
	RGBType RGB1, RGB2;
	HWBType HWB1, HWB2;
	float diff;

	SETUP_RGB(RGB1, r1, g1, b1);
	SETUP_RGB(RGB2, r2, g2, b2);

	RGB_to_HWB(RGB1, &HWB1);
	RGB_to_HWB(RGB2, &HWB2);

	/*
	 * I made this bit up; it seems to produce OK results, and it is certainly
	 * more visually correct than the current RGB metric. (PJW)
	 */

	if ((HWB1.H == HWB_UNDEFINED) || (HWB2.H == HWB_UNDEFINED)) {
		diff = 0.0f;	/* Undefined hues always match... */
	} else {
		diff = fabsf(HWB1.H - HWB2.H);
		if (diff > 3.0f) {
			diff = 6.0f - diff;	/* Remember, it's a colour circle */
		}
	}

	diff = diff * diff + (HWB1.W - HWB2.W) * (HWB1.W - HWB2.W) + (HWB1.B - HWB2.B) * (HWB1.B - HWB2.B);

	return diff;
}


#if 0
/*
 * This is not actually used, but is here for completeness, in case someone wants to
 * use the HWB stuff for anything else...
 */
static RGBType * HWB_to_RGB (HWBType HWB, RGBType * RGB)
{
	/*
	 * H is given on [0, 6] or UNDEFINED. W and B are given on [0, 1].
	 * RGB are each returned on [0, 1].
	 */

	float h = HWB.H, w = HWB.W, b = HWB.B, v, n, f;
	int i;

	v = 1 - b;
	if (h == HWB_UNDEFINED) {
		RETURN_RGB(v, v, v);
	}
	i = floor(h);
	f = h - i;
	if (i & 1) {
		f = 1 - f; /* if i is odd */
	}
	n = w + f * (v - w);		/* linear interpolation between w and v */
	switch (i) {
		case 6:
		case 0:
			RETURN_RGB(v, n, w);
		case 1:
			RETURN_RGB(n, v, w);
		case 2:
			RETURN_RGB(w, v, n);
		case 3:
			RETURN_RGB(w, n, v);
		case 4:
			RETURN_RGB(n, w, v);
		case 5:
			RETURN_RGB(v, w, n);
	}

	return RGB;
}
#endif

int gdImageColorClosestHWB (gdImagePtr im, int r, int g, int b)
{
	int i;
	/* long rd, gd, bd; */
	int ct = (-1);
	int first = 1;
	float mindist = 0;
	if (im->trueColor) {
		return gdTrueColor(r, g, b);
	}
	for (i = 0; i < im->colorsTotal; i++) {
		float dist;
		if (im->open[i]) {
			continue;
		}
		dist = HWB_Diff(im->red[i], im->green[i], im->blue[i], r, g, b);
		if (first || (dist < mindist)) {
			mindist = dist;
			ct = i;
			first = 0;
		}
	}
	return ct;
}

int gdImageColorExact (gdImagePtr im, int r, int g, int b)
{
	return gdImageColorExactAlpha (im, r, g, b, gdAlphaOpaque);
}

int gdImageColorExactAlpha (gdImagePtr im, int r, int g, int b, int a)
{
	int i;
	if (im->trueColor) {
		return gdTrueColorAlpha(r, g, b, a);
	}
	for (i = 0; i < im->colorsTotal; i++) {
		if (im->open[i]) {
			continue;
		}
		if ((im->red[i] == r) && (im->green[i] == g) && (im->blue[i] == b) && (im->alpha[i] == a)) {
			return i;
		}
	}
	return -1;
}

int gdImageColorAllocate (gdImagePtr im, int r, int g, int b)
{
	return gdImageColorAllocateAlpha (im, r, g, b, gdAlphaOpaque);
}

int gdImageColorAllocateAlpha (gdImagePtr im, int r, int g, int b, int a)
{
	int i;
	int ct = (-1);
	if (im->trueColor) {
		return gdTrueColorAlpha(r, g, b, a);
	}
	for (i = 0; i < im->colorsTotal; i++) {
		if (im->open[i]) {
			ct = i;
			break;
		}
	}
	if (ct == (-1)) {
		ct = im->colorsTotal;
		if (ct == gdMaxColors) {
			return -1;
		}
		im->colorsTotal++;
	}
	im->red[ct] = r;
	im->green[ct] = g;
	im->blue[ct] = b;
	im->alpha[ct] = a;
	im->open[ct] = 0;

	return ct;
}

/*
 * gdImageColorResolve is an alternative for the code fragment:
 *
 *      if ((color=gdImageColorExact(im,R,G,B)) < 0)
 *        if ((color=gdImageColorAllocate(im,R,G,B)) < 0)
 *          color=gdImageColorClosest(im,R,G,B);
 *
 * in a single function.    Its advantage is that it is guaranteed to
 * return a color index in one search over the color table.
 */

int gdImageColorResolve (gdImagePtr im, int r, int g, int b)
{
	return gdImageColorResolveAlpha(im, r, g, b, gdAlphaOpaque);
}

int gdImageColorResolveAlpha (gdImagePtr im, int r, int g, int b, int a)
{
  int c;
  int ct = -1;
  int op = -1;
  long rd, gd, bd, ad, dist;
  long mindist = 4 * 255 * 255;	/* init to max poss dist */
  if (im->trueColor)
    {
      return gdTrueColorAlpha (r, g, b, a);
    }

  for (c = 0; c < im->colorsTotal; c++)
    {
      if (im->open[c])
	{
	  op = c;		/* Save open slot */
	  continue;		/* Color not in use */
	}
      if (c == im->transparent)
        {
          /* don't ever resolve to the color that has
           * been designated as the transparent color */
          continue;
	}
      rd = (long) (im->red[c] - r);
      gd = (long) (im->green[c] - g);
      bd = (long) (im->blue[c] - b);
      ad = (long) (im->alpha[c] - a);
      dist = rd * rd + gd * gd + bd * bd + ad * ad;
      if (dist < mindist)
	{
	  if (dist == 0)
	    {
	      return c;		/* Return exact match color */
	    }
	  mindist = dist;
	  ct = c;
	}
    }
  /* no exact match.  We now know closest, but first try to allocate exact */
  if (op == -1)
    {
      op = im->colorsTotal;
      if (op == gdMaxColors)