ref: 733c5d6645b133b60d304c38fcb1398f94d0618c
dir: /sys/src/cmd/pic/pltroff.c/
#include <stdio.h>
#include <math.h>
#include <string.h>
#include "pic.h"
extern int dbg;
#define abs(n) (n >= 0 ? n : -(n))
#define max(x,y) ((x)>(y) ? (x) : (y))
char *textshift = "\\v'.2m'"; /* move text this far down */
/* scaling stuff defined by s command as X0,Y0 to X1,Y1 */
/* output dimensions set by -l,-w options to 0,0 to hmax, vmax */
/* default output is 6x6 inches */
double xscale;
double yscale;
double hpos = 0; /* current horizontal position in output coordinate system */
double vpos = 0; /* current vertical position; 0 is top of page */
double htrue = 0; /* where we really are */
double vtrue = 0;
double X0, Y0; /* left bottom of input */
double X1, Y1; /* right top of input */
double hmax; /* right end of output */
double vmax; /* top of output (down is positive) */
extern double deltx;
extern double delty;
extern double xmin, ymin, xmax, ymax;
double xconv(double), yconv(double), xsc(double), ysc(double);
void space(double, double, double, double);
void hgoto(double), vgoto(double), hmot(double), vmot(double);
void move(double, double), movehv(double, double);
void cont(double, double);
void openpl(char *s) /* initialize device; s is residue of .PS invocation line */
{
double maxw, maxh, ratio = 1;
double odeltx = deltx, odelty = delty;
hpos = vpos = 0;
maxw = getfval("maxpswid");
maxh = getfval("maxpsht");
if (deltx > maxw) { /* shrink horizontal */
ratio = maxw / deltx;
deltx *= ratio;
delty *= ratio;
}
if (delty > maxh) { /* shrink vertical */
ratio = maxh / delty;
deltx *= ratio;
delty *= ratio;
}
if (ratio != 1) {
fprintf(stderr, "pic: %g X %g picture shrunk to", odeltx, odelty);
fprintf(stderr, " %g X %g\n", deltx, delty);
}
space(xmin, ymin, xmax, ymax);
printf("... %g %g %g %g\n", xmin, ymin, xmax, ymax);
printf("... %.3fi %.3fi %.3fi %.3fi\n",
xconv(xmin), yconv(ymin), xconv(xmax), yconv(ymax));
printf(".nr 00 \\n(.u\n");
printf(".nf\n");
printf(".PS %.3fi %.3fi %s", yconv(ymin), xconv(xmax), s);
/* assumes \n comes as part of s */
}
void space(double x0, double y0, double x1, double y1) /* set limits of page */
{
X0 = x0;
Y0 = y0;
X1 = x1;
Y1 = y1;
xscale = deltx == 0.0 ? 1.0 : deltx / (X1-X0);
yscale = delty == 0.0 ? 1.0 : delty / (Y1-Y0);
}
double xconv(double x) /* convert x from external to internal form */
{
return (x-X0) * xscale;
}
double xsc(double x) /* convert x from external to internal form, scaling only */
{
return (x) * xscale;
}
double yconv(double y) /* convert y from external to internal form */
{
return (Y1-y) * yscale;
}
double ysc(double y) /* convert y from external to internal form, scaling only */
{
return (y) * yscale;
}
void closepl(char *PEline) /* clean up after finished */
{
movehv(0.0, 0.0); /* get back to where we started */
if (strchr(PEline, 'F') == NULL) {
printf(".sp 1+%.3fi\n", yconv(ymin));
}
printf("%s\n", PEline);
printf(".if \\n(00 .fi\n");
}
void move(double x, double y) /* go to position x, y in external coords */
{
hgoto(xconv(x));
vgoto(yconv(y));
}
void movehv(double h, double v) /* go to internal position h, v */
{
hgoto(h);
vgoto(v);
}
void hmot(double n) /* generate n units of horizontal motion */
{
hpos += n;
}
void vmot(double n) /* generate n units of vertical motion */
{
vpos += n;
}
void hgoto(double n)
{
hpos = n;
}
void vgoto(double n)
{
vpos = n;
}
double fabs(double x)
{
return x < 0 ? -x : x;
}
void hvflush(void) /* get to proper point for output */
{
if (fabs(hpos-htrue) >= 0.0005) {
printf("\\h'%.3fi'", hpos - htrue);
htrue = hpos;
}
if (fabs(vpos-vtrue) >= 0.0005) {
printf("\\v'%.3fi'", vpos - vtrue);
vtrue = vpos;
}
}
void flyback(void) /* return to upper left corner (entry point) */
{
printf(".sp -1\n");
htrue = vtrue = 0;
}
void printlf(int n, char *f)
{
if (f)
printf(".lf %d %s\n", n, f);
else
printf(".lf %d\n", n);
}
void troff(char *s) /* output troff right here */
{
printf("%s\n", s);
}
void label(char *s, int t, int nh) /* text s of type t nh half-lines up */
{
int q;
char *p;
if (!s)
return;
hvflush();
dprintf("label: %s %o %d\n", s, t, nh);
printf("%s", textshift); /* shift down and left */
if (t & ABOVE)
nh++;
else if (t & BELOW)
nh--;
if (nh)
printf("\\v'%du*\\n(.vu/2u'", -nh);
/* just in case the text contains a quote: */
q = 0;
for (p = s; *p; p++)
if (*p == '\'') {
q = 1;
break;
}
t &= ~(ABOVE|BELOW);
if (t & LJUST) {
printf("%s", s);
} else if (t & RJUST) {
if (q)
printf("\\h\\(ts-\\w\\(ts%s\\(tsu\\(ts%s", s, s);
else
printf("\\h'-\\w'%s'u'%s", s, s);
} else { /* CENTER */
if (q)
printf("\\h\\(ts-\\w\\(ts%s\\(tsu/2u\\(ts%s", s, s);
else
printf("\\h'-\\w'%s'u/2u'%s", s, s);
}
printf("\n");
flyback();
}
void line(double x0, double y0, double x1, double y1) /* draw line from x0,y0 to x1,y1 */
{
move(x0, y0);
cont(x1, y1);
}
void arrow(double x0, double y0, double x1, double y1, double w, double h,
double ang, int nhead) /* draw arrow (without shaft) */
{
double alpha, rot, drot, hyp;
double dx, dy;
int i;
rot = atan2(w / 2, h);
hyp = sqrt(w/2 * w/2 + h * h);
alpha = atan2(y1-y0, x1-x0) + ang;
if (nhead < 2)
nhead = 2;
dprintf("rot=%g, hyp=%g, alpha=%g\n", rot, hyp, alpha);
for (i = nhead-1; i >= 0; i--) {
drot = 2 * rot / (double) (nhead-1) * (double) i;
dx = hyp * cos(alpha + PI - rot + drot);
dy = hyp * sin(alpha + PI - rot + drot);
dprintf("dx,dy = %g,%g\n", dx, dy);
line(x1+dx, y1+dy, x1, y1);
}
}
double lastgray = 0;
void fillstart(double v) /* this works only for postscript, obviously. */
{ /* uses drechsler's dpost conventions... */
hvflush();
printf("\\X'BeginObject %g setgray'\n", v);
lastgray = v;
flyback();
}
void fillend(int vis, int fill)
{
hvflush();
printf("\\X'EndObject gsave eofill grestore %g setgray %s'\n",
!vis ? lastgray : 0.0,
vis ? "stroke" : "");
/* for dashed: [50] 0 setdash just before stroke. */
lastgray = 0;
flyback();
}
void box(double x0, double y0, double x1, double y1)
{
move(x0, y0);
cont(x0, y1);
cont(x1, y1);
cont(x1, y0);
cont(x0, y0);
}
void cont(double x, double y) /* continue line from here to x,y */
{
double h1, v1;
double dh, dv;
h1 = xconv(x);
v1 = yconv(y);
dh = h1 - hpos;
dv = v1 - vpos;
hvflush();
printf("\\D'l%.3fi %.3fi'\n", dh, dv);
flyback(); /* expensive */
hpos = h1;
vpos = v1;
}
void circle(double x, double y, double r)
{
move(x-r, y);
hvflush();
printf("\\D'c%.3fi'\n", xsc(2 * r));
flyback();
}
void spline(double x, double y, double n, ofloat *p, int dashed, double ddval)
{
int i;
double dx, dy;
double xerr, yerr;
move(x, y);
hvflush();
xerr = yerr = 0.0;
printf("\\D'~");
for (i = 0; i < 2 * n; i += 2) {
dx = xsc(xerr += p[i]);
xerr -= dx/xscale;
dy = ysc(yerr += p[i+1]);
yerr -= dy/yscale;
printf(" %.3fi %.3fi", dx, -dy); /* WATCH SIGN */
}
printf("'\n");
flyback();
}
void ellipse(double x, double y, double r1, double r2)
{
double ir1, ir2;
move(x-r1, y);
hvflush();
ir1 = xsc(r1);
ir2 = ysc(r2);
printf("\\D'e%.3fi %.3fi'\n", 2 * ir1, 2 * abs(ir2));
flyback();
}
void arc(double x, double y, double x0, double y0, double x1, double y1) /* draw arc with center x,y */
{
move(x0, y0);
hvflush();
printf("\\D'a%.3fi %.3fi %.3fi %.3fi'\n",
xsc(x-x0), -ysc(y-y0), xsc(x1-x), -ysc(y1-y)); /* WATCH SIGNS */
flyback();
}
void dot(void) {
hvflush();
/* what character to draw here depends on what's available. */
/* on the 202, l. is good but small. */
/* in general, use a smaller, shifted period and hope */
printf("\\&\\f1\\h'-.1m'\\v'.03m'\\s-3.\\s+3\\fP\n");
flyback();
}