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+/* magstep.h: declaration for magstep fixing.
+
+ Copyright 1994, 2008, 2009 Karl Berry.
+ Copyright 1999, 2005 Olaf Weber.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this library; if not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef KPATHSEA_MAGSTEP_H
+#define KPATHSEA_MAGSTEP_H
+
+#include <kpathsea/c-proto.h>
+#include <kpathsea/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* If DPI is close enough to some magstep of BDPI, return the true dpi
+ value, and the magstep found (or zero) in M_RET (if
+ non-null). ``Close enough'' means within one pixel.
+
+ M_RET is slightly encoded: the least significant bit is on for a
+ half-magstep, off otherwise. Thus, a returned M_RET of 1 means
+ \magstephalf, i.e., sqrt(1.2), i.e., 1.09544. Put another way,
+ return twice the number of magsteps.
+
+ In practice, this matters for magstephalf. Floating-point computation
+ with the fixed-point DVI representation leads to 328 (for BDPI ==
+ 300); specifying `at 11pt' yields 330; the true \magstephalf is 329
+ (that's what you get if you run Metafont with mag:=magstep(.5)).
+
+ The time to call this is after you read the font spec from the DVI
+ file, but before you look up any files -- do the usual floating-point
+ computations, and then fix up the result. */
+
+extern KPSEDLL unsigned kpathsea_magstep_fix (kpathsea kpse, unsigned dpi,
+ unsigned bdpi, int *m_ret);
+
+#if defined (KPSE_COMPAT_API)
+extern KPSEDLL unsigned kpse_magstep_fix (unsigned dpi, unsigned bdpi,
+ int *m_ret);
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* not KPATHSEA_MAGSTEP_H */