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gd.c
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gd.c
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#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); */
# ifndef fabsf
# define fabsf(x) ((float)(fabs(x)))
# endif
#endif
#if HAVE_FLOORF == 0
# ifndef floorf
/* float floorf(float x);*/
# define floorf(x) ((float)(floor(x)))
# endif
#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;
if (overflow2(sx, sy)) {
return NULL;
}
if (overflow2(sizeof(unsigned char *), sy)) {
return NULL;
}
im = (gdImage *) gdCalloc(1, 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;
if (overflow2(sx, sy)) {
return NULL;
}
if (overflow2(sizeof(unsigned char *), sy)) {
return NULL;
}
if (overflow2(sizeof(int), sx)) {
return NULL;
}
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)
{ /* No room for more colors */
return ct; /* Return closest available color */
}
im->colorsTotal++;
}
im->red[op] = r;
im->green[op] = g;
im->blue[op] = b;
im->alpha[op] = a;
im->open[op] = 0;
return op; /* Return newly allocated color */
}
void gdImageColorDeallocate (gdImagePtr im, int color)
{
if (im->trueColor) {
return;
}
/* Mark it open. */
im->open[color] = 1;
}
void gdImageColorTransparent (gdImagePtr im, int color)
{
if (!im->trueColor) {
if (im->transparent != -1) {
im->alpha[im->transparent] = gdAlphaOpaque;
}
if (color > -1 && color < im->colorsTotal && color < gdMaxColors) {
im->alpha[color] = gdAlphaTransparent;
} else {
return;
}
}
im->transparent = color;
}
void gdImagePaletteCopy (gdImagePtr to, gdImagePtr from)
{
int i;
int x, y, p;
int xlate[256];
if (to->trueColor || from->trueColor) {
return;
}
for (i = 0; i < 256; i++) {
xlate[i] = -1;
}
for (y = 0; y < to->sy; y++) {
for (x = 0; x < to->sx; x++) {
p = gdImageGetPixel(to, x, y);
if (xlate[p] == -1) {
/* This ought to use HWB, but we don't have an alpha-aware version of that yet. */
xlate[p] = gdImageColorClosestAlpha (from, to->red[p], to->green[p], to->blue[p], to->alpha[p]);
}
gdImageSetPixel(to, x, y, xlate[p]);
}
}
for (i = 0; i < from->colorsTotal; i++) {
to->red[i] = from->red[i];
to->blue[i] = from->blue[i];
to->green[i] = from->green[i];
to->alpha[i] = from->alpha[i];
to->open[i] = 0;
}
for (i = from->colorsTotal; i < to->colorsTotal; i++) {
to->open[i] = 1;
}
to->colorsTotal = from->colorsTotal;
}
/* 2.0.10: before the drawing routines, some code to clip points that are
* outside the drawing window. Nick Atty (nick@canalplan.org.uk)
*
* This is the Sutherland Hodgman Algorithm, as implemented by
* Duvanenko, Robbins and Gyurcsik - SH(DRG) for short. See Dr Dobb's
* Journal, January 1996, pp107-110 and 116-117
*
* Given the end points of a line, and a bounding rectangle (which we
* know to be from (0,0) to (SX,SY)), adjust the endpoints to be on
* the edges of the rectangle if the line should be drawn at all,
* otherwise return a failure code
*/
/* this does "one-dimensional" clipping: note that the second time it
* is called, all the x parameters refer to height and the y to width
* - the comments ignore this (if you can understand it when it's
* looking at the X parameters, it should become clear what happens on
* the second call!) The code is simplified from that in the article,
* as we know that gd images always start at (0,0)
*/
static int clip_1d(int *x0, int *y0, int *x1, int *y1, int maxdim) {
double m; /* gradient of line */
if (*x0 < 0) { /* start of line is left of window */
if(*x1 < 0) { /* as is the end, so the line never cuts the window */
return 0;
}
m = (*y1 - *y0)/(double)(*x1 - *x0); /* calculate the slope of the line */
/* adjust x0 to be on the left boundary (ie to be zero), and y0 to match */
*y0 -= (int)(m * *x0);
*x0 = 0;
/* now, perhaps, adjust the far end of the line as well */
if (*x1 > maxdim) {
*y1 += (int)(m * (maxdim - *x1));
*x1 = maxdim;
}
return 1;
}
if (*x0 > maxdim) { /* start of line is right of window - complement of above */
if (*x1 > maxdim) { /* as is the end, so the line misses the window */
return 0;
}
m = (*y1 - *y0)/(double)(*x1 - *x0); /* calculate the slope of the line */
*y0 += (int)(m * (maxdim - *x0)); /* adjust so point is on the right boundary */
*x0 = maxdim;
/* now, perhaps, adjust the end of the line */
if (*x1 < 0) {
*y1 -= (int)(m * *x1);
*x1 = 0;
}
return 1;
}
/* the final case - the start of the line is inside the window */
if (*x1 > maxdim) { /* other end is outside to the right */
m = (*y1 - *y0)/(double)(*x1 - *x0); /* calculate the slope of the line */
*y1 += (int)(m * (maxdim - *x1));
*x1 = maxdim;
return 1;
}
if (*x1 < 0) { /* other end is outside to the left */
m = (*y1 - *y0)/(double)(*x1 - *x0); /* calculate the slope of the line */
*y1 -= (int)(m * *x1);
*x1 = 0;
return 1;
}
/* only get here if both points are inside the window */
return 1;
}
void gdImageSetPixel (gdImagePtr im, int x, int y, int color)
{
int p;
switch (color) {
case gdStyled:
if (!im->style) {
/* Refuse to draw if no style is set. */
return;
} else {
p = im->style[im->stylePos++];
}
if (p != gdTransparent) {
gdImageSetPixel(im, x, y, p);
}
im->stylePos = im->stylePos % im->styleLength;
break;
case gdStyledBrushed:
if (!im->style) {
/* Refuse to draw if no style is set. */
return;
}
p = im->style[im->stylePos++];
if (p != gdTransparent && p != 0) {
gdImageSetPixel(im, x, y, gdBrushed);
}
im->stylePos = im->stylePos % im->styleLength;
break;
case gdBrushed:
gdImageBrushApply(im, x, y);
break;
case gdTiled:
gdImageTileApply(im, x, y);
break;
case gdAntiAliased:
gdImageAntiAliasedApply(im, x, y);
break;
default:
if (gdImageBoundsSafe(im, x, y)) {
if (im->trueColor) {
switch (im->alphaBlendingFlag) {
default:
case gdEffectReplace:
im->tpixels[y][x] = color;
break;
case gdEffectAlphaBlend:
im->tpixels[y][x] = gdAlphaBlend(im->tpixels[y][x], color);
break;
case gdEffectNormal:
im->tpixels[y][x] = gdAlphaBlend(im->tpixels[y][x], color);
break;
case gdEffectOverlay :
im->tpixels[y][x] = gdLayerOverlay(im->tpixels[y][x], color);
break;
}
} else {
im->pixels[y][x] = color;
}
}
break;
}
}
int gdImageGetTrueColorPixel (gdImagePtr im, int x, int y)
{
int p = gdImageGetPixel(im, x, y);
if (!im->trueColor) {
return gdTrueColorAlpha(im->red[p], im->green[p], im->blue[p], (im->transparent == p) ? gdAlphaTransparent : im->alpha[p]);
} else {
return p;
}
}
static void gdImageBrushApply (gdImagePtr im, int x, int y)
{
int lx, ly;
int hy, hx;
int x1, y1, x2, y2;
int srcx, srcy;
if (!im->brush) {
return;
}
hy = gdImageSY(im->brush) / 2;
y1 = y - hy;
y2 = y1 + gdImageSY(im->brush);
hx = gdImageSX(im->brush) / 2;
x1 = x - hx;
x2 = x1 + gdImageSX(im->brush);
srcy = 0;
if (im->trueColor) {
if (im->brush->trueColor) {
for (ly = y1; ly < y2; ly++) {
srcx = 0;
for (lx = x1; (lx < x2); lx++) {
int p;
p = gdImageGetTrueColorPixel(im->brush, srcx, srcy);
/* 2.0.9, Thomas Winzig: apply simple full transparency */
if (p != gdImageGetTransparent(im->brush)) {
gdImageSetPixel(im, lx, ly, p);
}
srcx++;
}
srcy++;
}
} else {
/* 2.0.12: Brush palette, image truecolor (thanks to Thorben Kundinger for pointing out the issue) */
for (ly = y1; ly < y2; ly++) {
srcx = 0;
for (lx = x1; lx < x2; lx++) {
int p, tc;
p = gdImageGetPixel(im->brush, srcx, srcy);
tc = gdImageGetTrueColorPixel(im->brush, srcx, srcy);
/* 2.0.9, Thomas Winzig: apply simple full transparency */
if (p != gdImageGetTransparent(im->brush)) {
gdImageSetPixel(im, lx, ly, tc);
}
srcx++;
}
srcy++;
}
}
} else {
for (ly = y1; ly < y2; ly++) {
srcx = 0;
for (lx = x1; lx < x2; lx++) {
int p;
p = gdImageGetPixel(im->brush, srcx, srcy);
/* Allow for non-square brushes! */
if (p != gdImageGetTransparent(im->brush)) {
/* Truecolor brush. Very slow on a palette destination. */
if (im->brush->trueColor) {
gdImageSetPixel(im, lx, ly, gdImageColorResolveAlpha(im, gdTrueColorGetRed(p),
gdTrueColorGetGreen(p),
gdTrueColorGetBlue(p),
gdTrueColorGetAlpha(p)));
} else {
gdImageSetPixel(im, lx, ly, im->brushColorMap[p]);
}
}
srcx++;
}
srcy++;
}
}
}
static void gdImageTileApply (gdImagePtr im, int x, int y)
{
gdImagePtr tile = im->tile;
int srcx, srcy;
int p;
if (!tile) {
return;
}
srcx = x % gdImageSX(tile);
srcy = y % gdImageSY(tile);
if (im->trueColor) {
p = gdImageGetPixel(tile, srcx, srcy);
if (p != gdImageGetTransparent (tile)) {
if (!tile->trueColor) {
p = gdTrueColorAlpha(tile->red[p], tile->green[p], tile->blue[p], tile->alpha[p]);
}
gdImageSetPixel(im, x, y, p);
}
} else {
p = gdImageGetPixel(tile, srcx, srcy);
/* Allow for transparency */
if (p != gdImageGetTransparent(tile)) {
if (tile->trueColor) {
/* Truecolor tile. Very slow on a palette destination. */
gdImageSetPixel(im, x, y, gdImageColorResolveAlpha(im,
gdTrueColorGetRed(p),
gdTrueColorGetGreen(p),
gdTrueColorGetBlue(p),
gdTrueColorGetAlpha(p)));
} else {
gdImageSetPixel(im, x, y, im->tileColorMap[p]);
}
}
}
}
static int gdImageTileGet (gdImagePtr im, int x, int y)
{
int srcx, srcy;
int tileColor,p;
if (!im->tile) {
return -1;
}
srcx = x % gdImageSX(im->tile);
srcy = y % gdImageSY(im->tile);
p = gdImageGetPixel(im->tile, srcx, srcy);
if (im->trueColor) {
if (im->tile->trueColor) {
tileColor = p;
} else {
tileColor = gdTrueColorAlpha( gdImageRed(im->tile,p), gdImageGreen(im->tile,p), gdImageBlue (im->tile,p), gdImageAlpha (im->tile,p));
}
} else {
if (im->tile->trueColor) {
tileColor = gdImageColorResolveAlpha(im, gdTrueColorGetRed (p), gdTrueColorGetGreen (p), gdTrueColorGetBlue (p), gdTrueColorGetAlpha (p));
} else {
tileColor = p;
tileColor = gdImageColorResolveAlpha(im, gdImageRed (im->tile,p), gdImageGreen (im->tile,p), gdImageBlue (im->tile,p), gdImageAlpha (im->tile,p));
}
}
return tileColor;
}
static void gdImageAntiAliasedApply (gdImagePtr im, int px, int py)
{
float p_dist, p_alpha;
unsigned char opacity;
/*
* Find the perpendicular distance from point C (px, py) to the line
* segment AB that is being drawn. (Adapted from an algorithm from the
* comp.graphics.algorithms FAQ.)
*/
int LAC_2, LBC_2;
int Ax_Cx = im->AAL_x1 - px;
int Ay_Cy = im->AAL_y1 - py;
int Bx_Cx = im->AAL_x2 - px;
int By_Cy = im->AAL_y2 - py;
/* 2.0.13: bounds check! AA_opacity is just as capable of
* overflowing as the main pixel array. Arne Jorgensen.
* 2.0.14: typo fixed. 2.0.15: moved down below declarations
* to satisfy non-C++ compilers.
*/
if (!gdImageBoundsSafe(im, px, py)) {
return;
}
/* Get the squares of the lengths of the segemnts AC and BC. */
LAC_2 = (Ax_Cx * Ax_Cx) + (Ay_Cy * Ay_Cy);
LBC_2 = (Bx_Cx * Bx_Cx) + (By_Cy * By_Cy);
if (((im->AAL_LAB_2 + LAC_2) >= LBC_2) && ((im->AAL_LAB_2 + LBC_2) >= LAC_2)) {
/* The two angles are acute. The point lies inside the portion of the
* plane spanned by the line segment.
*/
p_dist = fabs ((float) ((Ay_Cy * im->AAL_Bx_Ax) - (Ax_Cx * im->AAL_By_Ay)) / im->AAL_LAB);
} else {
/* The point is past an end of the line segment. It's length from the
* segment is the shorter of the lengths from the endpoints, but call
* the distance -1, so as not to compute the alpha nor draw the pixel.
*/
p_dist = -1;
}
if ((p_dist >= 0) && (p_dist <= (float) (im->thick))) {
p_alpha = pow (1.0 - (p_dist / 1.5), 2);
if (p_alpha > 0) {
if (p_alpha >= 1) {
opacity = 255;
} else {
opacity = (unsigned char) (p_alpha * 255.0);
}
if (!im->AA_polygon || (im->AA_opacity[py][px] < opacity)) {
im->AA_opacity[py][px] = opacity;
}
}
}
}
int gdImageGetPixel (gdImagePtr im, int x, int y)
{
if (gdImageBoundsSafe(im, x, y)) {
if (im->trueColor) {
return im->tpixels[y][x];
} else {
return im->pixels[y][x];
}