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/*
* Copyright (c) 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.
*/
/* DVI file information (as used by dvi-to-device programs) */
/*
* Units of distance are stored in scaled points, but we can convert to
* units of 10^-7 meters by multiplying by the numbers in the preamble.
* The values hh and vv are kept in device coordinates.
*/
/* the structure of the stack used to hold the values (h,v,hh,vv,w,x,y,z) */
typedef struct dvi_stack {
i32 h; /* the saved h */
i32 v; /* the saved v */
i32 hh; /* the saved hh */
i32 vv; /* the saved vv */
i32 w; /* etc */
i32 x;
i32 y;
i32 z;
} DviStack;
/*
* DVI state machine interpreter encapsulation (global state).
*/
struct dvi_state {
/*
* Variables that must be set by user before calling SetDVIState().
*/
int ds_usermag; /* user-supplied (additional) magnification */
int ds_maxdrift; /* maximum drift, typically 3 */
/* the rest are set by DVISetState() */
/*
* Values based on the (postamble of the) DVI file,
* or used by the interpreter.
*/
i32 ds_num; /* numerator from DVI file */
i32 ds_denom; /* denominator from DVI file */
i32 ds_dvimag; /* magnification from DVI file */
i32 ds_maxheight; /* height of tallest page */
i32 ds_maxwidth; /* width of widest page */
i32 ds_prevpage; /* previous page of DVI file */
int ds_npages; /* number of DVI pages */
DviStack *ds_stack; /* base of stack of DVI values */
DviStack *ds_sp; /* current place in stack */
DviStack ds_cur; /* current values */
DviStack ds_fresh; /* fresh values for new pages: not all
zero unless there are no margins.
This works because all DVI motion
is relative. */
/*
* Although this is not strictly within the realm of DVI
* state, we need a place to store the fonts we allocate
* while reading through the postamble. Each entry in
* the ds_fonts search table is a pointer to a font,
* so that *(struct font **)SSearch(...) is the pointer.
*/
struct search *ds_fonts;/* font table */
/*
* A few routines want a private copy of the DVI file pointer.
*/
FILE *ds_fp; /* input DVI file */
};
extern struct dvi_state ds;
/* shorthand */
#define dvi_h ds.ds_cur.h
#define dvi_v ds.ds_cur.v
#define dvi_hh ds.ds_cur.hh
#define dvi_vv ds.ds_cur.vv
#define dvi_w ds.ds_cur.w
#define dvi_x ds.ds_cur.x
#define dvi_y ds.ds_cur.y
#define dvi_z ds.ds_cur.z
/*
* Set up the state for the interpreter loop.
*/
void DVISetState();
/*
* Service routines (called from main loop).
*/
struct font *DVIFindFont();
void DVIRule(), DVIBeginPage();
/*
* Drift fixing. Note that the first argument must be an lvalue.
* It is the desired position in pixels, and is maintained within
* ds.ds_maxdrift pixels of the second argument, which is the
* `absolute' DVI position rounded to the nearest pixel.
*/
#define FIXDRIFT(xx, x) \
if ((x) >= (xx)) \
if ((x) - (xx) <= ds.ds_maxdrift) \
/* position is in bounds */; \
else \
(xx) = (x) - ds.ds_maxdrift; \
else \
if ((xx) - (x) <= ds.ds_maxdrift) \
/* position is in bounds */; \
else \
(xx) = (x) + ds.ds_maxdrift
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