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dvips551.zip
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DPICHECK.C
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C/C++ Source or Header
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1993-01-18
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2KB
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79 lines
/*
* This software is Copyright 1988 by Radical Eye Software.
*/
/*
* dpicheck of dvips.c. Checks the dots per inch to make sure
* it exists. The fonts which exist are DPI at the appropriate
* magnifications.
*/
#include "dvips.h"
extern int actualdpi ;
static integer existsizes[30] = { 0 , 99999999 } ;
static int checkdpi ;
/*
* This routine adds some sizes to `existsizes'.
*/
void addsiz(rhsize)
int rhsize ;
{
register integer *p ;
long t, hsize ;
hsize = rhsize ;
for (p=existsizes; *p < hsize; p++) ;
if (*p == hsize)
return ;
do {
t = *p ;
*p++ = hsize ;
hsize = t ;
} while (hsize) ;
}
void adddpi(hsize)
int hsize ;
{
long a, b, c ;
int i ;
addsiz(hsize) ;
addsiz((int)((hsize * 116161L + 53020L) / 106040L)) ;
a = hsize ;
b = 0 ;
c = 1 ;
for (i=0; i<9; i++) {
b = 6 * b + (a % 5) * c ;
a = a + a / 5 ;
c = c * 5 ;
if (b > c) {
b -= c ;
a++ ;
}
if (b + b >= c)
addsiz((int)(a+1)) ;
else
addsiz((int)a) ;
}
}
/*
* Finally, the routine that checks a size for match.
*/
halfword
dpicheck(dpi)
halfword dpi ;
{
integer i ;
integer margin = 1 + dpi / 500 ;
if (! checkdpi) {
adddpi(DPI) ;
checkdpi = 1 ;
}
for (i=0; existsizes[i] < dpi; i++) ;
if (existsizes[i]-dpi <= margin)
return(existsizes[i]) ;
else if (dpi-existsizes[i-1] <= margin)
return(existsizes[i-1]) ;
else
return(dpi) ;
}