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-rw-r--r--dviware/epson/eps-0.2/lib/conv.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/dviware/epson/eps-0.2/lib/conv.c b/dviware/epson/eps-0.2/lib/conv.c
new file mode 100644
index 0000000000..fbfc1f0430
--- /dev/null
+++ b/dviware/epson/eps-0.2/lib/conv.c
@@ -0,0 +1,53 @@
+#include "PROTO.h"
+/*
+ * Copyright (c) 1987, 1989 University of Maryland
+ * Department of Computer Science. All rights reserved.
+ * Permission to copy for any purpose is hereby granted
+ * so long as this copyright notice remains intact.
+ */
+
+#ifndef lint
+static char rcsid[] = "$Header: /usr/src/local/tex/local/mctex/lib/RCS/conv.c,v 3.1 89/08/22 21:48:01 chris Exp $";
+#endif
+
+/*
+ * Conversions.
+ */
+
+#include "types.h"
+#include "conv.h"
+
+double DMagFactor();
+
+Conv Conversion; /* the global conversion */
+
+/*
+ * Set a conversion (possibly the global conversion).
+ */
+extern void CSetConversion(register struct conversion *c, int hdpi, int vdpi, int usermag, i32 num, i32 denom, i32 dvimag)
+{
+ double dhdpi = hdpi;
+ double dvdpi = vdpi;
+
+ c->c_mag = DMagFactor((int) dvimag) * DMagFactor(usermag);
+ c->c_hdpi = dhdpi;
+ c->c_vdpi = dvdpi;
+
+ /*
+ * The conversion facture is figured as follows: there are exactly
+ * num/denom DVI units per decimicron, and 254000 decimicrons per
+ * inch, and dpi pixels per inch. Then we have to adjust this by
+ * the stated magnification.
+ */
+ c->c_fromsph = (num / 254000.0) * (dhdpi / denom) * c->c_mag;
+ c->c_fromspv = (num / 254000.0) * (dvdpi / denom) * c->c_mag;
+
+ /*
+ * c->c_tosp is 1/c->c_fromsp, but we will invert the expression
+ * above in the hopes of some extra accuracy.
+ *
+ * IS THIS ANY GOOD? I NEED A NUMERICAL ANALYST!
+ */
+ c->c_tosph = (254000.0 / num) * (denom / dhdpi) * (1.0 / c->c_mag);
+ c->c_tospv = (254000.0 / num) * (denom / dvdpi) * (1.0 / c->c_mag);
+}