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diff --git a/Build/source/texk/dvisvgm/dvisvgm-1.0.9/potracelib/decompose.c b/Build/source/texk/dvisvgm/dvisvgm-1.0.9/potracelib/decompose.c
new file mode 100644
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--- /dev/null
+++ b/Build/source/texk/dvisvgm/dvisvgm-1.0.9/potracelib/decompose.c
@@ -0,0 +1,514 @@
+/* Copyright (C) 2001-2011 Peter Selinger.
+ This file is part of Potrace. It is free software and it is covered
+ by the GNU General Public License. See the file COPYING for details. */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "lists.h"
+#include "bitmap.h"
+#include "decompose.h"
+#include "progress.h"
+
+/* ---------------------------------------------------------------------- */
+/* deterministically and efficiently hash (x,y) into a pseudo-random bit */
+
+static inline int detrand(int x, int y) {
+ unsigned int z;
+ static const unsigned char t[256] = {
+ /* non-linear sequence: constant term of inverse in GF(8),
+ mod x^8+x^4+x^3+x+1 */
+ 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1,
+ 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0,
+ 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1,
+ 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1,
+ 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0,
+ 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0,
+ 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0,
+ 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1,
+ 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0,
+ 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1,
+ 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+ };
+
+ /* 0x04b3e375 and 0x05a8ef93 are chosen to contain every possible
+ 5-bit sequence */
+ z = ((0x04b3e375 * x) ^ y) * 0x05a8ef93;
+ z = t[z & 0xff] ^ t[(z>>8) & 0xff] ^ t[(z>>16) & 0xff] ^ t[(z>>24) & 0xff];
+ return z;
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary bitmap manipulations */
+
+/* set the excess padding to 0 */
+static void bm_clearexcess(potrace_bitmap_t *bm) {
+ potrace_word mask;
+ int y;
+
+ if (bm->w % BM_WORDBITS != 0) {
+ mask = BM_ALLBITS << (BM_WORDBITS - (bm->w % BM_WORDBITS));
+ for (y=0; y<bm->h; y++) {
+ *bm_index(bm, bm->w, y) &= mask;
+ }
+ }
+}
+
+struct bbox_s {
+ int x0, x1, y0, y1; /* bounding box */
+};
+typedef struct bbox_s bbox_t;
+
+/* clear the bm, assuming the bounding box is set correctly (faster
+ than clearing the whole bitmap) */
+static void clear_bm_with_bbox(potrace_bitmap_t *bm, bbox_t *bbox) {
+ int imin = (bbox->x0 / BM_WORDBITS);
+ int imax = ((bbox->x1 + BM_WORDBITS-1) / BM_WORDBITS);
+ int i, y;
+
+ for (y=bbox->y0; y<bbox->y1; y++) {
+ for (i=imin; i<imax; i++) {
+ bm_scanline(bm, y)[i] = 0;
+ }
+ }
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions */
+
+/* return the "majority" value of bitmap bm at intersection (x,y). We
+ assume that the bitmap is balanced at "radius" 1. */
+static int majority(potrace_bitmap_t *bm, int x, int y) {
+ int i, a, ct;
+
+ for (i=2; i<5; i++) { /* check at "radius" i */
+ ct = 0;
+ for (a=-i+1; a<=i-1; a++) {
+ ct += BM_GET(bm, x+a, y+i-1) ? 1 : -1;
+ ct += BM_GET(bm, x+i-1, y+a-1) ? 1 : -1;
+ ct += BM_GET(bm, x+a-1, y-i) ? 1 : -1;
+ ct += BM_GET(bm, x-i, y+a) ? 1 : -1;
+ }
+ if (ct>0) {
+ return 1;
+ } else if (ct<0) {
+ return 0;
+ }
+ }
+ return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* decompose image into paths */
+
+/* efficiently invert bits [x,infty) and [xa,infty) in line y. Here xa
+ must be a multiple of BM_WORDBITS. */
+static void xor_to_ref(potrace_bitmap_t *bm, int x, int y, int xa) {
+ int xhi = x & -BM_WORDBITS;
+ int xlo = x & (BM_WORDBITS-1); /* = x % BM_WORDBITS */
+ int i;
+
+ if (xhi<xa) {
+ for (i = xhi; i < xa; i+=BM_WORDBITS) {
+ *bm_index(bm, i, y) ^= BM_ALLBITS;
+ }
+ } else {
+ for (i = xa; i < xhi; i+=BM_WORDBITS) {
+ *bm_index(bm, i, y) ^= BM_ALLBITS;
+ }
+ }
+ /* note: the following "if" is needed because x86 treats a<<b as
+ a<<(b&31). I spent hours looking for this bug. */
+ if (xlo) {
+ *bm_index(bm, xhi, y) ^= (BM_ALLBITS << (BM_WORDBITS - xlo));
+ }
+}
+
+/* a path is represented as an array of points, which are thought to
+ lie on the corners of pixels (not on their centers). The path point
+ (x,y) is the lower left corner of the pixel (x,y). Paths are
+ represented by the len/pt components of a path_t object (which
+ also stores other information about the path) */
+
+/* xor the given pixmap with the interior of the given path. Note: the
+ path must be within the dimensions of the pixmap. */
+static void xor_path(potrace_bitmap_t *bm, path_t *p) {
+ int xa, x, y, k, y1;
+
+ if (p->priv->len <= 0) { /* a path of length 0 is silly, but legal */
+ return;
+ }
+
+ y1 = p->priv->pt[p->priv->len-1].y;
+
+ xa = p->priv->pt[0].x & -BM_WORDBITS;
+ for (k=0; k<p->priv->len; k++) {
+ x = p->priv->pt[k].x;
+ y = p->priv->pt[k].y;
+
+ if (y != y1) {
+ /* efficiently invert the rectangle [x,xa] x [y,y1] */
+ xor_to_ref(bm, x, min(y,y1), xa);
+ y1 = y;
+ }
+ }
+}
+
+/* Find the bounding box of a given path. Path is assumed to be of
+ non-zero length. */
+static void setbbox_path(bbox_t *bbox, path_t *p) {
+ int x, y;
+ int k;
+
+ bbox->y0 = INT_MAX;
+ bbox->y1 = 0;
+ bbox->x0 = INT_MAX;
+ bbox->x1 = 0;
+
+ for (k=0; k<p->priv->len; k++) {
+ x = p->priv->pt[k].x;
+ y = p->priv->pt[k].y;
+
+ if (x < bbox->x0) {
+ bbox->x0 = x;
+ }
+ if (x > bbox->x1) {
+ bbox->x1 = x;
+ }
+ if (y < bbox->y0) {
+ bbox->y0 = y;
+ }
+ if (y > bbox->y1) {
+ bbox->y1 = y;
+ }
+ }
+}
+
+/* compute a path in the given pixmap, separating black from white.
+ Start path at the point (x0,x1), which must be an upper left corner
+ of the path. Also compute the area enclosed by the path. Return a
+ new path_t object, or NULL on error (note that a legitimate path
+ cannot have length 0). Sign is required for correct interpretation
+ of turnpolicies. */
+static path_t *findpath(potrace_bitmap_t *bm, int x0, int y0, int sign, int turnpolicy) {
+ int x, y, dirx, diry, len, size, area;
+ int c, d, tmp;
+ point_t *pt, *pt1;
+ path_t *p = NULL;
+
+ x = x0;
+ y = y0;
+ dirx = 0;
+ diry = -1;
+
+ len = size = 0;
+ pt = NULL;
+ area = 0;
+
+ while (1) {
+ /* add point to path */
+ if (len>=size) {
+ size += 100;
+ size = (int)(1.3 * size);
+ pt1 = (point_t *)realloc(pt, size * sizeof(point_t));
+ if (!pt1) {
+ goto error;
+ }
+ pt = pt1;
+ }
+ pt[len].x = x;
+ pt[len].y = y;
+ len++;
+
+ /* move to next point */
+ x += dirx;
+ y += diry;
+ area += x*diry;
+
+ /* path complete? */
+ if (x==x0 && y==y0) {
+ break;
+ }
+
+ /* determine next direction */
+ c = BM_GET(bm, x + (dirx+diry-1)/2, y + (diry-dirx-1)/2);
+ d = BM_GET(bm, x + (dirx-diry-1)/2, y + (diry+dirx-1)/2);
+
+ if (c && !d) { /* ambiguous turn */
+ if (turnpolicy == POTRACE_TURNPOLICY_RIGHT
+ || (turnpolicy == POTRACE_TURNPOLICY_BLACK && sign == '+')
+ || (turnpolicy == POTRACE_TURNPOLICY_WHITE && sign == '-')
+ || (turnpolicy == POTRACE_TURNPOLICY_RANDOM && detrand(x,y))
+ || (turnpolicy == POTRACE_TURNPOLICY_MAJORITY && majority(bm, x, y))
+ || (turnpolicy == POTRACE_TURNPOLICY_MINORITY && !majority(bm, x, y))) {
+ tmp = dirx; /* right turn */
+ dirx = diry;
+ diry = -tmp;
+ } else {
+ tmp = dirx; /* left turn */
+ dirx = -diry;
+ diry = tmp;
+ }
+ } else if (c) { /* right turn */
+ tmp = dirx;
+ dirx = diry;
+ diry = -tmp;
+ } else if (!d) { /* left turn */
+ tmp = dirx;
+ dirx = -diry;
+ diry = tmp;
+ }
+ } /* while this path */
+
+ /* allocate new path object */
+ p = potrace_path_new();
+ if (!p) {
+ goto error;
+ }
+
+ p->priv->pt = pt;
+ p->priv->len = len;
+ p->area = area;
+ p->sign = sign;
+
+ return p;
+
+ error:
+ free(pt);
+ return NULL;
+}
+
+/* Give a tree structure to the given path list, based on "insideness"
+ testing. I.e., path A is considered "below" path B if it is inside
+ path B. The input pathlist is assumed to be ordered so that "outer"
+ paths occur before "inner" paths. The tree structure is stored in
+ the "childlist" and "sibling" components of the path_t
+ structure. The linked list structure is also changed so that
+ negative path components are listed immediately after their
+ positive parent. Note: some backends may ignore the tree
+ structure, others may use it e.g. to group path components. We
+ assume that in the input, point 0 of each path is an "upper left"
+ corner of the path, as returned by bm_to_pathlist. This makes it
+ easy to find an "interior" point. The bm argument should be a
+ bitmap of the correct size (large enough to hold all the paths),
+ and will be used as scratch space. Return 0 on success or -1 on
+ error with errno set. */
+
+static void pathlist_to_tree(path_t *plist, potrace_bitmap_t *bm) {
+ path_t *p, *p1;
+ path_t *heap, *heap1;
+ path_t *cur;
+ path_t *head;
+ path_t **plist_hook; /* for fast appending to linked list */
+ path_t **hook_in, **hook_out; /* for fast appending to linked list */
+ bbox_t bbox;
+
+ bm_clear(bm, 0);
+
+ /* save original "next" pointers */
+ list_forall(p, plist) {
+ p->sibling = p->next;
+ p->childlist = NULL;
+ }
+
+ heap = plist;
+
+ /* the heap holds a list of lists of paths. Use "childlist" field
+ for outer list, "next" field for inner list. Each of the sublists
+ is to be turned into a tree. This code is messy, but it is
+ actually fast. Each path is rendered exactly once. We use the
+ heap to get a tail recursive algorithm: the heap holds a list of
+ pathlists which still need to be transformed. */
+
+ while (heap) {
+ /* unlink first sublist */
+ cur = heap;
+ heap = heap->childlist;
+ cur->childlist = NULL;
+
+ /* unlink first path */
+ head = cur;
+ cur = cur->next;
+ head->next = NULL;
+
+ /* render path */
+ xor_path(bm, head);
+ setbbox_path(&bbox, head);
+
+ /* now do insideness test for each element of cur; append it to
+ head->childlist if it's inside head, else append it to
+ head->next. */
+ hook_in=&head->childlist;
+ hook_out=&head->next;
+ list_forall_unlink(p, cur) {
+ if (p->priv->pt[0].y <= bbox.y0) {
+ list_insert_beforehook(p, hook_out);
+ /* append the remainder of the list to hook_out */
+ *hook_out = cur;
+ break;
+ }
+ if (BM_GET(bm, p->priv->pt[0].x, p->priv->pt[0].y-1)) {
+ list_insert_beforehook(p, hook_in);
+ } else {
+ list_insert_beforehook(p, hook_out);
+ }
+ }
+
+ /* clear bm */
+ clear_bm_with_bbox(bm, &bbox);
+
+ /* now schedule head->childlist and head->next for further
+ processing */
+ if (head->next) {
+ head->next->childlist = heap;
+ heap = head->next;
+ }
+ if (head->childlist) {
+ head->childlist->childlist = heap;
+ heap = head->childlist;
+ }
+ }
+
+ /* copy sibling structure from "next" to "sibling" component */
+ p = plist;
+ while (p) {
+ p1 = p->sibling;
+ p->sibling = p->next;
+ p = p1;
+ }
+
+ /* reconstruct a new linked list ("next") structure from tree
+ ("childlist", "sibling") structure. This code is slightly messy,
+ because we use a heap to make it tail recursive: the heap
+ contains a list of childlists which still need to be
+ processed. */
+ heap = plist;
+ if (heap) {
+ heap->next = NULL; /* heap is a linked list of childlists */
+ }
+ plist = NULL;
+ plist_hook = &plist;
+ while (heap) {
+ heap1 = heap->next;
+ for (p=heap; p; p=p->sibling) {
+ /* p is a positive path */
+ /* append to linked list */
+ list_insert_beforehook(p, plist_hook);
+
+ /* go through its children */
+ for (p1=p->childlist; p1; p1=p1->sibling) {
+ /* append to linked list */
+ list_insert_beforehook(p1, plist_hook);
+ /* append its childlist to heap, if non-empty */
+ if (p1->childlist) {
+ list_append(path_t, heap1, p1->childlist);
+ }
+ }
+ }
+ heap = heap1;
+ }
+
+ return;
+}
+
+/* find the next set pixel in a row <= y. Pixels are searched first
+ left-to-right, then top-down. In other words, (x,y)<(x',y') if y>y'
+ or y=y' and x<x'. If found, return 0 and store pixel in
+ (*xp,*yp). Else return 1. Note that this function assumes that
+ excess bytes have been cleared with bm_clearexcess. */
+static int findnext(potrace_bitmap_t *bm, int *xp, int *yp) {
+ int x;
+ int y;
+ int x0;
+
+ x0 = (*xp) & ~(BM_WORDBITS-1);
+
+ for (y=*yp; y>=0; y--) {
+ for (x=x0; x<bm->w; x+=BM_WORDBITS) {
+ if (*bm_index(bm, x, y)) {
+ while (!BM_GET(bm, x, y)) {
+ x++;
+ }
+ /* found */
+ *xp = x;
+ *yp = y;
+ return 0;
+ }
+ }
+ x0 = 0;
+ }
+ /* not found */
+ return 1;
+}
+
+/* Decompose the given bitmap into paths. Returns a linked list of
+ path_t objects with the fields len, pt, area, sign filled
+ in. Returns 0 on success with plistp set, or -1 on error with errno
+ set. */
+
+int bm_to_pathlist(const potrace_bitmap_t *bm, path_t **plistp, const potrace_param_t *param, progress_t *progress) {
+ int x;
+ int y;
+ path_t *p;
+ path_t *plist = NULL; /* linked list of path objects */
+ path_t **plist_hook = &plist; /* used to speed up appending to linked list */
+ potrace_bitmap_t *bm1 = NULL;
+ int sign;
+
+ bm1 = bm_dup(bm);
+ if (!bm1) {
+ goto error;
+ }
+
+ /* be sure the byte padding on the right is set to 0, as the fast
+ pixel search below relies on it */
+ bm_clearexcess(bm1);
+
+ /* iterate through components */
+ x = 0;
+ y = bm1->h - 1;
+ while (findnext(bm1, &x, &y) == 0) {
+ /* calculate the sign by looking at the original */
+ sign = BM_GET(bm, x, y) ? '+' : '-';
+
+ /* calculate the path */
+ p = findpath(bm1, x, y+1, sign, param->turnpolicy);
+ if (p==NULL) {
+ goto error;
+ }
+
+ /* update buffered image */
+ xor_path(bm1, p);
+
+ /* if it's a turd, eliminate it, else append it to the list */
+ if (p->area <= param->turdsize) {
+ potrace_path_free(p);
+ } else {
+ list_insert_beforehook(p, plist_hook);
+ }
+
+ if (bm1->h > 0) { /* to be sure */
+ progress_update(1-y/(double)bm1->h, progress);
+ }
+ }
+
+ pathlist_to_tree(plist, bm1);
+ bm_free(bm1);
+ *plistp = plist;
+
+ progress_update(1.0, progress);
+
+ return 0;
+
+ error:
+ bm_free(bm1);
+ list_forall_unlink(p, plist) {
+ potrace_path_free(p);
+ }
+ return -1;
+}
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