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+// -*- 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 "pic.h"
+#include "common.h"
+
+// output a dashed circle as a series of arcs
+
+void common_output::dashed_circle(const position &cent, double rad,
+ const line_type &lt)
+{
+ assert(lt.type == line_type::dashed);
+ line_type slt = lt;
+ slt.type = line_type::solid;
+ double dash_angle = lt.dash_width/rad;
+ int ndashes;
+ double gap_angle;
+ if (dash_angle >= M_PI/4.0) {
+ if (dash_angle < M_PI/2.0) {
+ gap_angle = M_PI/2.0 - dash_angle;
+ ndashes = 4;
+ }
+ else if (dash_angle < M_PI) {
+ gap_angle = M_PI - dash_angle;
+ ndashes = 2;
+ }
+ else {
+ circle(cent, rad, slt, -1.0);
+ return;
+ }
+ }
+ else {
+ ndashes = 4*int(ceil(M_PI/(4.0*dash_angle)));
+ gap_angle = (M_PI*2.0)/ndashes - dash_angle;
+ }
+ for (int i = 0; i < ndashes; i++) {
+ double start_angle = i*(dash_angle+gap_angle) - dash_angle/2.0;
+ solid_arc(cent, rad, start_angle, start_angle + dash_angle, lt);
+ }
+}
+
+// output a dotted circle as a series of dots
+
+void common_output::dotted_circle(const position &cent, double rad,
+ const line_type &lt)
+{
+ assert(lt.type == line_type::dotted);
+ double gap_angle = lt.dash_width/rad;
+ int ndots;
+ if (gap_angle >= M_PI/2.0) {
+ // always have at least 2 dots
+ gap_angle = M_PI;
+ ndots = 2;
+ }
+ else {
+ ndots = 4*int(M_PI/(2.0*gap_angle));
+ gap_angle = (M_PI*2.0)/ndots;
+ }
+ double ang = 0.0;
+ for (int i = 0; i < ndots; i++, ang += gap_angle)
+ dot(cent + position(cos(ang), sin(ang))*rad, lt);
+}
+
+// return non-zero iff we can compute a center
+
+int compute_arc_center(const position &start, const position &cent,
+ const position &end, position *result)
+{
+ // This finds the point along the vector from start to cent that
+ // is equidistant between start and end.
+ distance c = cent - start;
+ distance e = end - start;
+ double n = c*e;
+ if (n == 0.0)
+ return 0;
+ *result = start + c*((e*e)/(2.0*n));
+ return 1;
+}
+
+// output a dashed arc as a series of arcs
+
+void common_output::dashed_arc(const position &start, const position &cent,
+ const position &end, const line_type &lt)
+{
+ assert(lt.type == line_type::dashed);
+ position c;
+ if (!compute_arc_center(start, cent, end, &c)) {
+ line(start, &end, 1, lt);
+ return;
+ }
+ distance start_offset = start - c;
+ distance end_offset = end - c;
+ double start_angle = atan2(start_offset.y, start_offset.x);
+ double end_angle = atan2(end_offset.y, end_offset.x);
+ double rad = hypot(c - start);
+ double dash_angle = lt.dash_width/rad;
+ double total_angle = end_angle - start_angle;
+ while (total_angle < 0)
+ total_angle += M_PI + M_PI;
+ if (total_angle <= dash_angle*2.0) {
+ solid_arc(cent, rad, start_angle, end_angle, lt);
+ return;
+ }
+ int ndashes = int((total_angle - dash_angle)/(dash_angle*2.0) + .5);
+ double dash_and_gap_angle = (total_angle - dash_angle)/ndashes;
+ for (int i = 0; i <= ndashes; i++)
+ solid_arc(cent, rad, start_angle + i*dash_and_gap_angle,
+ start_angle + i*dash_and_gap_angle + dash_angle, lt);
+}
+
+// output a dotted arc as a series of dots
+
+void common_output::dotted_arc(const position &start, const position &cent,
+ const position &end, const line_type &lt)
+{
+ assert(lt.type == line_type::dotted);
+ position c;
+ if (!compute_arc_center(start, cent, end, &c)) {
+ line(start, &end, 1, lt);
+ return;
+ }
+ distance start_offset = start - c;
+ distance end_offset = end - c;
+ double start_angle = atan2(start_offset.y, start_offset.x);
+ double total_angle = atan2(end_offset.y, end_offset.x) - start_angle;
+ while (total_angle < 0)
+ total_angle += M_PI + M_PI;
+ double rad = hypot(c - start);
+ int ndots = int(total_angle/(lt.dash_width/rad) + .5);
+ if (ndots == 0)
+ dot(start, lt);
+ else {
+ for (int i = 0; i <= ndots; i++) {
+ double a = start_angle + (total_angle*i)/ndots;
+ dot(cent + position(cos(a), sin(a))*rad, lt);
+ }
+ }
+}
+
+void common_output::solid_arc(const position &cent, double rad,
+ double start_angle, double end_angle,
+ const line_type &lt)
+{
+ line_type slt = lt;
+ slt.type = line_type::solid;
+ arc(cent + position(cos(start_angle), sin(start_angle))*rad,
+ cent,
+ cent + position(cos(end_angle), sin(end_angle))*rad,
+ slt);
+}
+
+
+void common_output::rounded_box(const position &cent, const distance &dim,
+ double rad, const line_type &lt, double fill)
+{
+ if (fill >= 0.0)
+ filled_rounded_box(cent, dim, rad, fill);
+ switch (lt.type) {
+ case line_type::invisible:
+ break;
+ case line_type::dashed:
+ dashed_rounded_box(cent, dim, rad, lt);
+ break;
+ case line_type::dotted:
+ dotted_rounded_box(cent, dim, rad, lt);
+ break;
+ case line_type::solid:
+ solid_rounded_box(cent, dim, rad, lt);
+ break;
+ default:
+ assert(0);
+ }
+}
+
+
+void common_output::dashed_rounded_box(const position &cent,
+ const distance &dim, double rad,
+ const line_type &lt)
+{
+ line_type slt = lt;
+ slt.type = line_type::solid;
+
+ double hor_length = dim.x + (M_PI/2.0 - 2.0)*rad;
+ int n_hor_dashes = int(hor_length/(lt.dash_width*2.0) + .5);
+ double hor_gap_width = (n_hor_dashes != 0
+ ? hor_length/n_hor_dashes - lt.dash_width
+ : 0.0);
+
+ double vert_length = dim.y + (M_PI/2.0 - 2.0)*rad;
+ int n_vert_dashes = int(vert_length/(lt.dash_width*2.0) + .5);
+ double vert_gap_width = (n_vert_dashes != 0
+ ? vert_length/n_vert_dashes - lt.dash_width
+ : 0.0);
+ // Note that each corner arc has to be split into two for dashing,
+ // because one part is dashed using vert_gap_width, and the other
+ // using hor_gap_width.
+ double offset = lt.dash_width/2.0;
+ dash_arc(cent + position(dim.x/2.0 - rad, -dim.y/2.0 + rad), rad,
+ -M_PI/4.0, 0, slt, lt.dash_width, vert_gap_width, &offset);
+ dash_line(cent + position(dim.x/2.0, -dim.y/2.0 + rad),
+ cent + position(dim.x/2.0, dim.y/2.0 - rad),
+ slt, lt.dash_width, vert_gap_width, &offset);
+ dash_arc(cent + position(dim.x/2.0 - rad, dim.y/2.0 - rad), rad,
+ 0, M_PI/4.0, slt, lt.dash_width, vert_gap_width, &offset);
+
+ offset = lt.dash_width/2.0;
+ dash_arc(cent + position(dim.x/2.0 - rad, dim.y/2.0 - rad), rad,
+ M_PI/4.0, M_PI/2, slt, lt.dash_width, hor_gap_width, &offset);
+ dash_line(cent + position(dim.x/2.0 - rad, dim.y/2.0),
+ cent + position(-dim.x/2.0 + rad, dim.y/2.0),
+ slt, lt.dash_width, hor_gap_width, &offset);
+ dash_arc(cent + position(-dim.x/2.0 + rad, dim.y/2.0 - rad), rad,
+ M_PI/2, 3*M_PI/4.0, slt, lt.dash_width, hor_gap_width, &offset);
+
+ offset = lt.dash_width/2.0;
+ dash_arc(cent + position(-dim.x/2.0 + rad, dim.y/2.0 - rad), rad,
+ 3.0*M_PI/4.0, M_PI, slt, lt.dash_width, vert_gap_width, &offset);
+ dash_line(cent + position(-dim.x/2.0, dim.y/2.0 - rad),
+ cent + position(-dim.x/2.0, -dim.y/2.0 + rad),
+ slt, lt.dash_width, vert_gap_width, &offset);
+ dash_arc(cent + position(-dim.x/2.0 + rad, -dim.y/2.0 + rad), rad,
+ M_PI, 5.0*M_PI/4.0, slt, lt.dash_width, vert_gap_width, &offset);
+
+ offset = lt.dash_width/2.0;
+ dash_arc(cent + position(-dim.x/2.0 + rad, -dim.y/2.0 + rad), rad,
+ 5*M_PI/4.0, 3*M_PI/2.0, slt, lt.dash_width, hor_gap_width, &offset);
+ dash_line(cent + position(-dim.x/2.0 + rad, -dim.y/2.0),
+ cent + position(dim.x/2.0 - rad, -dim.y/2.0),
+ slt, lt.dash_width, hor_gap_width, &offset);
+ dash_arc(cent + position(dim.x/2.0 - rad, -dim.y/2.0 + rad), rad,
+ 3*M_PI/2, 7*M_PI/4, slt, lt.dash_width, hor_gap_width, &offset);
+}
+
+// Used by dashed_rounded_box.
+
+void common_output::dash_arc(const position &cent, double rad,
+ double start_angle, double end_angle,
+ const line_type &lt,
+ double dash_width, double gap_width,
+ double *offsetp)
+{
+ double length = (end_angle - start_angle)*rad;
+ double pos = 0.0;
+ for (;;) {
+ if (*offsetp >= dash_width) {
+ double rem = dash_width + gap_width - *offsetp;
+ if (pos + rem > length) {
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ pos += rem;
+ *offsetp = 0.0;
+ }
+ }
+ else {
+ double rem = dash_width - *offsetp;
+ if (pos + rem > length) {
+ solid_arc(cent, rad, start_angle + pos/rad, end_angle, lt);
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ solid_arc(cent, rad, start_angle + pos/rad,
+ start_angle + (pos + rem)/rad, lt);
+ pos += rem;
+ *offsetp = dash_width;
+ }
+ }
+ }
+}
+
+// Used by dashed_rounded_box.
+
+void common_output::dash_line(const position &start, const position &end,
+ const line_type &lt,
+ double dash_width, double gap_width,
+ double *offsetp)
+{
+ distance dist = end - start;
+ double length = hypot(dist);
+ if (length == 0.0)
+ return;
+ double pos = 0.0;
+ for (;;) {
+ if (*offsetp >= dash_width) {
+ double rem = dash_width + gap_width - *offsetp;
+ if (pos + rem > length) {
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ pos += rem;
+ *offsetp = 0.0;
+ }
+ }
+ else {
+ double rem = dash_width - *offsetp;
+ if (pos + rem > length) {
+ line(start + dist*(pos/length), &end, 1, lt);
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ position p(start + dist*((pos + rem)/length));
+ line(start + dist*(pos/length), &p, 1, lt);
+ pos += rem;
+ *offsetp = dash_width;
+ }
+ }
+ }
+}
+
+void common_output::dotted_rounded_box(const position &cent,
+ const distance &dim, double rad,
+ const line_type &lt)
+{
+ line_type slt = lt;
+ slt.type = line_type::solid;
+
+ double hor_length = dim.x + (M_PI/2.0 - 2.0)*rad;
+ int n_hor_dots = int(hor_length/lt.dash_width + .5);
+ double hor_gap_width = (n_hor_dots != 0
+ ? hor_length/n_hor_dots
+ : lt.dash_width);
+
+ double vert_length = dim.y + (M_PI/2.0 - 2.0)*rad;
+ int n_vert_dots = int(vert_length/lt.dash_width + .5);
+ double vert_gap_width = (n_vert_dots != 0
+ ? vert_length/n_vert_dots
+ : lt.dash_width);
+ double epsilon = lt.dash_width/(rad*100.0);
+
+ double offset = 0.0;
+ dot_arc(cent + position(dim.x/2.0 - rad, -dim.y/2.0 + rad), rad,
+ -M_PI/4.0, 0, slt, vert_gap_width, &offset);
+ dot_line(cent + position(dim.x/2.0, -dim.y/2.0 + rad),
+ cent + position(dim.x/2.0, dim.y/2.0 - rad),
+ slt, vert_gap_width, &offset);
+ dot_arc(cent + position(dim.x/2.0 - rad, dim.y/2.0 - rad), rad,
+ 0, M_PI/4.0 - epsilon, slt, vert_gap_width, &offset);
+
+ offset = 0.0;
+ dot_arc(cent + position(dim.x/2.0 - rad, dim.y/2.0 - rad), rad,
+ M_PI/4.0, M_PI/2, slt, hor_gap_width, &offset);
+ dot_line(cent + position(dim.x/2.0 - rad, dim.y/2.0),
+ cent + position(-dim.x/2.0 + rad, dim.y/2.0),
+ slt, hor_gap_width, &offset);
+ dot_arc(cent + position(-dim.x/2.0 + rad, dim.y/2.0 - rad), rad,
+ M_PI/2, 3*M_PI/4.0 - epsilon, slt, hor_gap_width, &offset);
+
+ offset = 0.0;
+ dot_arc(cent + position(-dim.x/2.0 + rad, dim.y/2.0 - rad), rad,
+ 3.0*M_PI/4.0, M_PI, slt, vert_gap_width, &offset);
+ dot_line(cent + position(-dim.x/2.0, dim.y/2.0 - rad),
+ cent + position(-dim.x/2.0, -dim.y/2.0 + rad),
+ slt, vert_gap_width, &offset);
+ dot_arc(cent + position(-dim.x/2.0 + rad, -dim.y/2.0 + rad), rad,
+ M_PI, 5.0*M_PI/4.0 - epsilon, slt, vert_gap_width, &offset);
+
+ offset = 0.0;
+ dot_arc(cent + position(-dim.x/2.0 + rad, -dim.y/2.0 + rad), rad,
+ 5*M_PI/4.0, 3*M_PI/2.0, slt, hor_gap_width, &offset);
+ dot_line(cent + position(-dim.x/2.0 + rad, -dim.y/2.0),
+ cent + position(dim.x/2.0 - rad, -dim.y/2.0),
+ slt, hor_gap_width, &offset);
+ dot_arc(cent + position(dim.x/2.0 - rad, -dim.y/2.0 + rad), rad,
+ 3*M_PI/2, 7*M_PI/4 - epsilon, slt, hor_gap_width, &offset);
+}
+
+// Used by dotted_rounded_box.
+
+void common_output::dot_arc(const position &cent, double rad,
+ double start_angle, double end_angle,
+ const line_type &lt, double gap_width,
+ double *offsetp)
+{
+ double length = (end_angle - start_angle)*rad;
+ double pos = 0.0;
+ for (;;) {
+ if (*offsetp == 0.0) {
+ double ang = start_angle + pos/rad;
+ dot(cent + position(cos(ang), sin(ang))*rad, lt);
+ }
+ double rem = gap_width - *offsetp;
+ if (pos + rem > length) {
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ pos += rem;
+ *offsetp = 0.0;
+ }
+ }
+}
+
+// Used by dotted_rounded_box.
+
+void common_output::dot_line(const position &start, const position &end,
+ const line_type &lt, double gap_width,
+ double *offsetp)
+{
+ distance dist = end - start;
+ double length = hypot(dist);
+ if (length == 0.0)
+ return;
+ double pos = 0.0;
+ for (;;) {
+ if (*offsetp == 0.0)
+ dot(start + dist*(pos/length), lt);
+ double rem = gap_width - *offsetp;
+ if (pos + rem > length) {
+ *offsetp += length - pos;
+ break;
+ }
+ else {
+ pos += rem;
+ *offsetp = 0.0;
+ }
+ }
+}
+
+
+void common_output::solid_rounded_box(const position &cent,
+ const distance &dim, double rad,
+ const line_type &lt)
+{
+ position tem = cent - dim/2.0;
+ arc(tem + position(0.0, rad),
+ tem + position(rad, rad),
+ tem + position(rad, 0.0),
+ lt);
+ tem = cent + position(-dim.x/2.0, dim.y/2.0);
+ arc(tem + position(rad, 0.0),
+ tem + position(rad, -rad),
+ tem + position(0.0, -rad),
+ lt);
+ tem = cent + dim/2.0;
+ arc(tem + position(0.0, -rad),
+ tem + position(-rad, -rad),
+ tem + position(-rad, 0.0),
+ lt);
+ tem = cent + position(dim.x/2.0, -dim.y/2.0);
+ arc(tem + position(-rad, 0.0),
+ tem + position(-rad, rad),
+ tem + position(0.0, rad),
+ lt);
+ position end;
+ end = cent + position(-dim.x/2.0, dim.y/2.0 - rad);
+ line(cent - dim/2.0 + position(0.0, rad), &end, 1, lt);
+ end = cent + position(dim.x/2.0 - rad, dim.y/2.0);
+ line(cent + position(-dim.x/2.0 + rad, dim.y/2.0), &end, 1, lt);
+ end = cent + position(dim.x/2.0, -dim.y/2.0 + rad);
+ line(cent + position(dim.x/2.0, dim.y/2.0 - rad), &end, 1, lt);
+ end = cent + position(-dim.x/2.0 + rad, -dim.y/2.0);
+ line(cent + position(dim.x/2.0 - rad, -dim.y/2.0), &end, 1, lt);
+}
+
+void common_output::filled_rounded_box(const position &cent,
+ const distance &dim, double rad,
+ double fill)
+{
+ line_type ilt;
+ ilt.type = line_type::invisible;
+ circle(cent + position(dim.x/2.0 - rad, dim.y/2.0 - rad), rad, ilt, fill);
+ circle(cent + position(-dim.x/2.0 + rad, dim.y/2.0 - rad), rad, ilt, fill);
+ circle(cent + position(-dim.x/2.0 + rad, -dim.y/2.0 + rad), rad, ilt, fill);
+ circle(cent + position(dim.x/2.0 - rad, -dim.y/2.0 + rad), rad, ilt, fill);
+ position vec[4];
+ vec[0] = cent + position(dim.x/2.0, dim.y/2.0 - rad);
+ vec[1] = cent + position(-dim.x/2.0, dim.y/2.0 - rad);
+ vec[2] = cent + position(-dim.x/2.0, -dim.y/2.0 + rad);
+ vec[3] = cent + position(dim.x/2.0, -dim.y/2.0 + rad);
+ polygon(vec, 4, ilt, fill);
+ vec[0] = cent + position(dim.x/2.0 - rad, dim.y/2.0);
+ vec[1] = cent + position(-dim.x/2.0 + rad, dim.y/2.0);
+ vec[2] = cent + position(-dim.x/2.0 + rad, -dim.y/2.0);
+ vec[3] = cent + position(dim.x/2.0 - rad, -dim.y/2.0);
+ polygon(vec, 4, ilt, fill);
+}