*
* - linearised PDF, perhaps?
*
- * - compression of output files. For the actual text display,
- * both output formats currently average about 50-60 characters
- * per 5-6 character word of text, and almost all of it's the
- * same.
- * * In PS, we can define custom text operators to make things
- * more efficient.
- * * In PDF, there already are!
- *
* - I'm uncertain of whether I need to include a ToUnicode CMap
* in each of my font definitions in PDF. Currently things (by
* which I mean cut and paste out of acroread) seem to be
}
static void add_string_to_page(page_data *page, int x, int y,
- font_encoding *fe, int size, char *text)
+ font_encoding *fe, int size, char *text,
+ int width)
{
text_fragment *frag;
frag->fe = fe;
frag->fontsize = size;
frag->text = dupstr(text);
+ frag->width = width;
}
/*
if (!subfont || sf != subfont) {
if (subfont) {
text[textpos] = '\0';
- add_string_to_page(page, x, y, subfont, fontsize, text);
+ add_string_to_page(page, x, y, subfont, fontsize, text,
+ textwid);
x += textwid;
} else {
assert(textpos == 0);
if (textpos > 0) {
text[textpos] = '\0';
- add_string_to_page(page, x, y, subfont, fontsize, text);
+ add_string_to_page(page, x, y, subfont, fontsize, text, textwid);
x += textwid;
}
static object *new_object(objlist *list);
static void objtext(object *o, char const *text);
static void objstream(object *o, char const *text);
+static void pdf_string(void (*add)(object *, char const *),
+ object *, char const *);
static void objref(object *o, object *dest);
static void make_pages_node(object *node, object *parent, page_data *first,
for (page = doc->pages; page; page = page->next) {
object *opage, *cstr;
rect *r;
- text_fragment *frag;
+ text_fragment *frag, *frag_end;
char buf[256];
+ int x, y, lx, ly;
opage = (object *)page->spare;
/*
}
objstream(cstr, "BT\n");
- for (frag = page->first_text; frag; frag = frag->next) {
- char *c;
+ /*
+ * PDF tracks two separate current positions: the position
+ * given in the `line matrix' and the position given in the
+ * `text matrix'. We must therefore track both as well.
+ * They start off at -1 (unset).
+ */
+ lx = ly = -1;
+ x = y = -1;
+
+ frag = page->first_text;
+ while (frag) {
+ /*
+ * For compactness, I'm going to group text fragments
+ * into subsequences that use the same font+size. So
+ * first find the end of this subsequence.
+ */
+ for (frag_end = frag;
+ (frag_end &&
+ frag_end->fe == frag->fe &&
+ frag_end->fontsize == frag->fontsize);
+ frag_end = frag_end->next);
+
+ /*
+ * Now select the text fragment, and prepare to display
+ * the text.
+ */
objstream(cstr, "/");
objstream(cstr, frag->fe->name);
- sprintf(buf, " %d Tf 1 0 0 1 %g %g Tm (", frag->fontsize,
- frag->x/4096.0, frag->y/4096.0);
+ sprintf(buf, " %d Tf ", frag->fontsize);
objstream(cstr, buf);
- for (c = frag->text; *c; c++) {
- if (*c == '(' || *c == ')' || *c == '\\')
- objstream(cstr, "\\");
- buf[0] = *c;
- buf[1] = '\0';
+ while (frag && frag != frag_end) {
+ /*
+ * Place the text position for the first piece of
+ * text.
+ */
+ if (lx < 0) {
+ sprintf(buf, "1 0 0 1 %g %g Tm ",
+ frag->x/4096.0, frag->y/4096.0);
+ } else {
+ sprintf(buf, "%g %g Td ",
+ (frag->x - lx)/4096.0, (frag->y - ly)/4096.0);
+ }
objstream(cstr, buf);
+ lx = x = frag->x;
+ ly = y = frag->y;
+
+ /*
+ * See if we're going to use Tj (show a single
+ * string) or TJ (show an array of strings with
+ * x-spacings between them). We determine this by
+ * seeing if there's more than one text fragment in
+ * sequence with the same y-coordinate.
+ */
+ if (frag->next && frag->next != frag_end &&
+ frag->next->y == y) {
+ /*
+ * The TJ strategy.
+ */
+ objstream(cstr, "[");
+ while (frag && frag != frag_end && frag->y == y) {
+ if (frag->x != x) {
+ sprintf(buf, "%g",
+ (x - frag->x) * 1000.0 /
+ (4096.0 * frag->fontsize));
+ objstream(cstr, buf);
+ }
+ pdf_string(objstream, cstr, frag->text);
+ x = frag->x + frag->width;
+ frag = frag->next;
+ }
+ objstream(cstr, "]TJ\n");
+ } else
+ {
+ /*
+ * The Tj strategy.
+ */
+ pdf_string(objstream, cstr, frag->text);
+ objstream(cstr, "Tj\n");
+ frag = frag->next;
+ }
}
-
- objstream(cstr, ") Tj\n");
}
objstream(cstr, "ET");
objref(annot, (object *)xr->dest.page->spare);
objtext(annot, " /XYZ null null null]\n");
} else {
- char *p;
-
- objtext(annot, "/A <<\n/Type /Action\n/S /URI\n/URI (");
- for (p = xr->dest.url; *p; p++) {
- char c[2];
- c[0] = *p;
- c[1] = '\0';
- if (*p == '(' || *p == ')' || *p == '\\')
- objtext(annot, "\\");
- objtext(annot, c);
- }
- objtext(annot, ")\n>>\n");
+ objtext(annot, "/A <<\n/Type /Action\n/S /URI\n/URI ");
+ pdf_string(objtext, annot, xr->dest.url);
+ objtext(annot, "\n>>\n");
}
objtext(annot, ">>\n");
level = items->level;
while (n > 0) {
- char *title, *p;
+ char *title;
/*
* Here we expect to be sitting on an item at the given
curr = new_object(parent->list);
if (!first) first = curr;
last = curr;
- objtext(curr, "<<\n/Title (");
- for (p = title; *p; p++) {
- char c[2];
- if (*p == '\\' || *p == '(' || *p == ')')
- objtext(curr, "\\");
- c[0] = *p;
- c[1] = '\0';
- objtext(curr, c);
- }
- objtext(curr, ")\n/Parent ");
+ objtext(curr, "<<\n/Title ");
+ pdf_string(objtext, curr, title);
+ objtext(curr, "\n/Parent ");
objref(curr, parent);
objtext(curr, "\n/Dest [");
objref(curr, (object *)items->pdata->first->page->spare);
return ret;
}
+
+static void pdf_string(void (*add)(object *, char const *),
+ object *o, char const *str)
+{
+ char const *p;
+
+ add(o, "(");
+ for (p = str; *p; p++) {
+ char c[2];
+ if (*p == '\\' || *p == '(' || *p == ')')
+ add(o, "\\");
+ c[0] = *p;
+ c[1] = '\0';
+ add(o, c);
+ }
+ add(o, ")");
+}
fprintf(fp, "%%%%EndComments\n");
fprintf(fp, "%%%%BeginProlog\n");
+ /*
+ * Supply a prologue function which allows a reasonably
+ * compressed representation of the text on the pages.
+ *
+ * Expects two arguments: a y-coordinate, and then an array.
+ * Elements of the array are processed sequentially as follows:
+ *
+ * - a number is treated as an x-coordinate
+ * - an array is treated as a (font, size) pair
+ * - a string is shown
+ */
+ fprintf(fp,
+ "/t {\n"
+ " exch /y exch def {\n"
+ " /x exch def\n"
+ " x type [] type eq {x aload pop scalefont setfont} if\n"
+ " x type dup 1 type eq exch 1.0 type eq or {x y moveto} if\n"
+ " x type () type eq {x show} if\n"
+ " } forall\n"
+ "} def\n");
+
fprintf(fp, "%%%%EndProlog\n");
fprintf(fp, "%%%%BeginSetup\n");
*/
pageno = 0;
for (page = doc->pages; page; page = page->next) {
- text_fragment *frag;
+ text_fragment *frag, *frag_end;
rect *r;
pageno++;
r->h / 4096.0, r->w / 4096.0);
}
- for (frag = page->first_text; frag; frag = frag->next) {
+ frag = page->first_text;
+ while (frag) {
+ font_encoding *fe;
+ int fs;
char *c;
- fprintf(fp, "%s %d scalefont setfont %g %g moveto (",
- frag->fe->name, frag->fontsize,
- frag->x/4096.0, frag->y/4096.0);
+ /*
+ * Collect all the adjacent text fragments with the
+ * same y-coordinate.
+ */
+ for (frag_end = frag;
+ frag_end && frag_end->y == frag->y;
+ frag_end = frag_end->next);
+
+ fprintf(fp, "%g[", frag->y / 4096.0);
+
+ fe = NULL;
+ fs = -1;
+
+ while (frag && frag != frag_end) {
+
+ if (frag->fe != fe || frag->fontsize != fs)
+ fprintf(fp, "[%s %d]", frag->fe->name, frag->fontsize);
+ fe = frag->fe;
+ fs = frag->fontsize;
+
+ fprintf(fp, "%g(", frag->x/4096.0);
+ for (c = frag->text; *c; c++) {
+ if (*c == '(' || *c == ')' || *c == '\\')
+ fputc('\\', fp);
+ fputc(*c, fp);
+ }
+ fprintf(fp, ")");
- for (c = frag->text; *c; c++) {
- if (*c == '(' || *c == ')' || *c == '\\')
- fputc('\\', fp);
- fputc(*c, fp);
+ frag = frag->next;
}
- fprintf(fp, ") show\n");
+ fprintf(fp, "]t\n");
}
fprintf(fp, "showpage\n");