freebsd-dev/contrib/groff/libdriver/printer.cc

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1996-09-07 16:18:32 +00:00
// -*- C++ -*-
/* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
Written by James Clark (jjc@jclark.com)
This file is part of groff.
groff is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
groff 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 General Public License
for more details.
You should have received a copy of the GNU General Public License along
with groff; see the file COPYING. If not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "driver.h"
printer *pr = 0;
font_pointer_list::font_pointer_list(font *f, font_pointer_list *fp)
: p(f), next(fp)
{
}
printer::printer()
: font_table(0), nfonts(0), font_list(0)
{
}
printer::~printer()
{
a_delete font_table;
while (font_list) {
font_pointer_list *tem = font_list;
font_list = font_list->next;
delete tem->p;
delete tem;
}
if (ferror(stdout) || fflush(stdout) < 0)
fatal("output error");
}
void printer::load_font(int n, const char *nm)
{
assert(n >= 0);
if (n >= nfonts) {
if (nfonts == 0) {
nfonts = 10;
if (nfonts <= n)
nfonts = n + 1;
font_table = new font *[nfonts];
for (int i = 0; i < nfonts; i++)
font_table[i] = 0;
}
else {
font **old_font_table = font_table;
int old_nfonts = nfonts;
nfonts *= 2;
if (n >= nfonts)
nfonts = n + 1;
font_table = new font *[nfonts];
int i;
for (i = 0; i < old_nfonts; i++)
font_table[i] = old_font_table[i];
for (i = old_nfonts; i < nfonts; i++)
font_table[i] = 0;
a_delete old_font_table;
}
}
font *f = find_font(nm);
font_table[n] = f;
}
font *printer::find_font(const char *nm)
{
for (font_pointer_list *p = font_list; p; p = p->next)
if (strcmp(p->p->get_name(), nm) == 0)
return p->p;
font *f = make_font(nm);
if (!f)
fatal("sorry, I can't continue");
font_list = new font_pointer_list(f, font_list);
return f;
}
font *printer::make_font(const char *nm)
{
return font::load_font(nm);
}
void printer::end_of_line()
{
}
void printer::special(char *, const environment *)
{
}
void printer::draw(int, int *, int, const environment *)
{
}
void printer::set_ascii_char(unsigned char c, const environment *env,
int *widthp)
{
char buf[2];
buf[0] = c;
buf[1] = '\0';
set_special_char(buf, env, widthp);
}
void printer::set_special_char(const char *nm, const environment *env,
int *widthp)
{
int i = font::name_to_index(nm);
int fn = env->fontno;
if (fn < 0 || fn >= nfonts) {
error("bad font position `%1'", fn);
return;
}
font *f = font_table[fn];
if (f == 0) {
error("no font mounted at `%1'", fn);
return;
}
if (!f->contains(i)) {
if (nm[0] != '\0' && nm[1] == '\0')
error("font `%1' does not contain ascii character `%2'",
f->get_name(),
nm[0]);
else
error("font `%1' does not contain special character `%2'",
f->get_name(),
nm);
return;
}
int w = f->get_width(i, env->size);
if (widthp)
*widthp = w;
set_char(i, f, env, w);
}
void printer::set_numbered_char(int num, const environment *env, int *widthp)
{
int i = font::number_to_index(num);
int fn = env->fontno;
if (fn < 0 || fn >= nfonts) {
error("bad font position `%1'", fn);
return;
}
font *f = font_table[fn];
if (f == 0) {
error("no font mounted at `%1'", fn);
return;
}
if (!f->contains(i)) {
error("font `%1' does not contain numbered character %2",
f->get_name(),
num);
return;
}
int w = f->get_width(i, env->size);
if (widthp)
*widthp = w;
set_char(i, f, env, w);
}
// This utility function adjusts the specified center of the
// arc so that it is equidistant between the specified start
// and end points. (p[0], p[1]) is a vector from the current
// point to the center; (p[2], p[3]) is a vector from the
// center to the end point. If the center can be adjusted,
// a vector from the current point to the adjusted center is
// stored in c[0], c[1] and 1 is returned. Otherwise 0 is
// returned.
#if 1
int printer::adjust_arc_center(const int *p, double *c)
{
// We move the center along a line parallel to the line between
// the specified start point and end point so that the center
// is equidistant between the start and end point.
// It can be proved (using Lagrange multipliers) that this will
// give the point nearest to the specified center that is equidistant
// between the start and end point.
double x = p[0] + p[2]; // (x, y) is the end point
double y = p[1] + p[3];
double n = x*x + y*y;
if (n != 0) {
c[0]= double(p[0]);
c[1] = double(p[1]);
double k = .5 - (c[0]*x + c[1]*y)/n;
c[0] += k*x;
c[1] += k*y;
return 1;
}
else
return 0;
}
#else
int printer::adjust_arc_center(const int *p, double *c)
{
int x = p[0] + p[2]; // (x, y) is the end point
int y = p[1] + p[3];
// Start at the current point; go in the direction of the specified
// center point until we reach a point that is equidistant between
// the specified starting point and the specified end point. Place
// the center of the arc there.
double n = p[0]*double(x) + p[1]*double(y);
if (n > 0) {
double k = (double(x)*x + double(y)*y)/(2.0*n);
// (cx, cy) is our chosen center
c[0] = k*p[0];
c[1] = k*p[1];
return 1;
}
else {
// We would never reach such a point. So instead start at the
// specified end point of the arc. Go towards the specified
// center point until we reach a point that is equidistant between
// the specified start point and specified end point. Place
// the center of the arc there.
n = p[2]*double(x) + p[3]*double(y);
if (n > 0) {
double k = 1 - (double(x)*x + double(y)*y)/(2.0*n);
// (c[0], c[1]) is our chosen center
c[0] = p[0] + k*p[2];
c[1] = p[1] + k*p[3];
return 1;
}
else
return 0;
}
}
#endif