type1: Use correct glyph advance when subsetting type 1 fonts

Previously the glyph advance in font units was used for the widths in
the PDF font dictionary. This only works for Type 1 fonts that use a
[0.001 0 0 0.001 0 0] font matrix.

https://bugs.freedesktop.org/show_bug.cgi?id=28061

src/cairo-pdf-surface.c

@@ -3849,6 +3849,8 @@ _cairo_pdf_surface_emit_to_unicode_stream (cairo_pdf_surface_t		*surface,
     return _cairo_pdf_surface_close_stream (surface);
 }
 
+#define PDF_UNITS_PER_EM 1000
+
 static cairo_status_t
 _cairo_pdf_surface_emit_cff_font (cairo_pdf_surface_t		*surface,
                                   cairo_scaled_font_subset_t	*font_subset,
@@ -4088,7 +4090,7 @@ _cairo_pdf_surface_emit_type1_font (cairo_pdf_surface_t		*surface,
 				 "   /ItalicAngle 0\n"
 				 "   /Ascent %ld\n"
 				 "   /Descent %ld\n"
-				 "   /CapHeight 500\n"
+				 "   /CapHeight %ld\n"
 				 "   /StemV 80\n"
 				 "   /StemH 80\n"
 				 "   /FontFile %u 0 R\n"
@@ -4097,12 +4099,13 @@ _cairo_pdf_surface_emit_type1_font (cairo_pdf_surface_t		*surface,
 				 descriptor.id,
 				 tag,
 				 subset->base_font,
-				 subset->x_min,
-				 subset->y_min,
-				 subset->x_max,
-				 subset->y_max,
-				 subset->ascent,
-				 subset->descent,
+				 (long)(subset->x_min*PDF_UNITS_PER_EM),
+				 (long)(subset->y_min*PDF_UNITS_PER_EM),
+				 (long)(subset->x_max*PDF_UNITS_PER_EM),
+				 (long)(subset->y_max*PDF_UNITS_PER_EM),
+				 (long)(subset->ascent*PDF_UNITS_PER_EM),
+				 (long)(subset->descent*PDF_UNITS_PER_EM),
+				 (long)(subset->y_max*PDF_UNITS_PER_EM),
 				 stream.id);
 
     _cairo_pdf_surface_update_object (surface, subset_resource);
@@ -4123,8 +4126,8 @@ _cairo_pdf_surface_emit_type1_font (cairo_pdf_surface_t		*surface,
 
     for (i = 0; i < font_subset->num_glyphs; i++)
 	_cairo_output_stream_printf (surface->output,
-				     " %d",
-				     subset->widths[i]);
+				     " %ld",
+                                     (long)(subset->widths[i]*PDF_UNITS_PER_EM));
 
     _cairo_output_stream_printf (surface->output,
 				 " ]\n");
@@ -4186,8 +4189,6 @@ _cairo_pdf_surface_emit_type1_fallback_font (cairo_pdf_surface_t	*surface,
     return status;
 }
 
-#define PDF_UNITS_PER_EM 1000
-
 static cairo_status_t
 _cairo_pdf_surface_emit_truetype_font_subset (cairo_pdf_surface_t		*surface,
 					      cairo_scaled_font_subset_t	*font_subset)

src/cairo-scaled-font-subsets-private.h

@@ -451,9 +451,9 @@ _cairo_truetype_subset_fini (cairo_truetype_subset_t *truetype_subset);
 
 typedef struct _cairo_type1_subset {
     char *base_font;
-    int *widths;
-    long x_min, y_min, x_max, y_max;
-    long ascent, descent;
+    double *widths;
+    double x_min, y_min, x_max, y_max;
+    double ascent, descent;
     char *data;
     unsigned long header_length;
     unsigned long data_length;

src/cairo-type1-fallback.c

@@ -727,20 +727,20 @@ _cairo_type1_fallback_init_internal (cairo_type1_subset_t	*type1_subset,
         goto fail1;
     }
 
-    type1_subset->widths = calloc (sizeof (int), font->scaled_font_subset->num_glyphs);
+    type1_subset->widths = calloc (sizeof (double), font->scaled_font_subset->num_glyphs);
     if (unlikely (type1_subset->widths == NULL)) {
         status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
         goto fail2;
     }
     for (i = 0; i < font->scaled_font_subset->num_glyphs; i++)
-	type1_subset->widths[i] = font->widths[i];
-
-    type1_subset->x_min   = (int) font->x_min;
-    type1_subset->y_min   = (int) font->y_min;
-    type1_subset->x_max   = (int) font->x_max;
-    type1_subset->y_max   = (int) font->y_max;
-    type1_subset->ascent  = (int) font->y_max;
-    type1_subset->descent = (int) font->y_min;
+	type1_subset->widths[i] = (double)font->widths[i]/1000;
+
+    type1_subset->x_min   = (double)font->x_min/1000;
+    type1_subset->y_min   = (double)font->y_min/1000;
+    type1_subset->x_max   = (double)font->x_max/1000;
+    type1_subset->y_max   = (double)font->y_max/1000;
+    type1_subset->ascent  = (double)font->y_max/1000;
+    type1_subset->descent = (double)font->y_min/1000;
 
     length = font->header_size + font->data_size +
 	font->trailer_size;

src/cairo-type1-subset.c

@@ -83,7 +83,7 @@ typedef struct _cairo_type1_font_subset {
 
     struct {
 	int subset_index;
-	int width;
+	double width;
 	char *name;
     } *glyphs;
 
@@ -566,7 +566,7 @@ cairo_type1_font_subset_get_glyph_names_and_widths (cairo_type1_font_subset_t *f
 	    return CAIRO_INT_STATUS_UNSUPPORTED;
 	}
 
-	font->glyphs[i].width = font->face->glyph->metrics.horiAdvance;
+	font->glyphs[i].width = font->face->glyph->linearHoriAdvance / 65536.0; /* 16.16 format */
 
 	error = FT_Get_Glyph_Name(font->face, i, buffer, sizeof buffer);
 	if (error != FT_Err_Ok) {
@@ -1346,7 +1346,7 @@ _cairo_type1_subset_init (cairo_type1_subset_t		*type1_subset,
     if (unlikely (type1_subset->base_font == NULL))
 	goto fail1;
 
-    type1_subset->widths = calloc (sizeof (int), font.num_glyphs);
+    type1_subset->widths = calloc (sizeof (double), font.num_glyphs);
     if (unlikely (type1_subset->widths == NULL))
 	goto fail2;
     for (i = 0; i < font.base.num_glyphs; i++) {