Reduce the changes that mupdfclean makes to floats.

Most of the changes mupdfclean makes to a file are purely textual
(streams are decompressed etc), but some objects can undergo changes
due to being read in, and then written out. Notably in this class
are floats. For instance, the mediabox in Bug689189.pdf contains
2125.984, which when written out with the current code gives 2125.98.

This is enough of a difference to cause rendering changes.

By upping the precision (instead of %g use, %1.9g) we get better
results; we now output 2125.9839, which is much closer (and in fact
has the same float representation when read back in).

This drastically reduces the differences between a rendering of
Bug689189.pdf and the uncompressed version, but we still have
differences - in shadings, it seems.

1 files changed, 1 insertions, 1 deletions

diff --git a/pdf/base_object.c b/pdf/base_object.c
index 6f0c5d99..97cb97cc 100644
--- a/pdf/base_object.c
+++ b/pdf/base_object.c
@@ -1183,7 +1183,7 @@ static void fmt_obj(struct fmt *fmt, pdf_obj *obj)
 	}
 	else if (pdf_is_real(obj))
 	{
-		sprintf(buf, "%g", pdf_to_real(obj));
+		sprintf(buf, "%1.9g", pdf_to_real(obj));
 		if (strchr(buf, 'e')) /* bad news! */
 			sprintf(buf, fabsf(pdf_to_real(obj)) > 1 ? "%1.1f" : "%1.8f", pdf_to_real(obj));
 		fmt_puts(fmt, buf);