Lout 3.17.

git-svn-id: http://svn.savannah.nongnu.org/svn/lout/trunk@2 9365b830-b601-4143-9ba8-b4a8e2c3339c

1 files changed, 112 insertions, 0 deletions

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+/*@z34.c:Rotation Service:Declarations@***************************************/
+/*                                                                           */
+/*  THE LOUT DOCUMENT FORMATTING SYSTEM (VERSION 3.17)                       */
+/*  COPYRIGHT (C) 1991, 1999 Jeffrey H. Kingston                             */
+/*                                                                           */
+/*  Jeffrey H. Kingston (jeff@cs.usyd.edu.au)                                */
+/*  Basser Department of Computer Science                                    */
+/*  The University of Sydney 2006                                            */
+/*  AUSTRALIA                                                                */
+/*                                                                           */
+/*  This program 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.                                                       */
+/*                                                                           */
+/*  This program 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 this program; if not, write to the Free Software              */
+/*  Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307 USA   */
+/*                                                                           */
+/*  FILE:         z34.c                                                      */
+/*  MODULE:       Rotation Service                                           */
+/*  EXTERNS:      RotateSize()                                               */
+/*                                                                           */
+/*****************************************************************************/
+#include <math.h>
+#ifndef M_PI
+#define M_PI       3.1415926535897931160E0
+#endif
+#include "externs.h"
+
+typedef struct { double x, y;          } rect_coord;
+typedef struct { double angle, radius; } polar_coord;
+
+#define rect_to_polar(rect, polar)				\
+polar.angle = atan2(rect.y, rect.x),				\
+polar.radius = sqrt(rect.x*rect.x + rect.y*rect.y)
+
+#define polar_to_rect(polar, rect)				\
+rect.x = polar.radius * cos(polar.angle),			\
+rect.y = polar.radius * sin(polar.angle)
+
+
+/*@::RotateSize()@************************************************************/
+/*                                                                           */
+/*  RotateSize(xcb, xcf, xrb, xrf, y, theta)                                 */
+/*                                                                           */
+/*  Calculate the size of x, assuming that it is y rotated by theta degrees. */
+/*                                                                           */
+/*****************************************************************************/
+
+void RotateSize(FULL_LENGTH *xcb, FULL_LENGTH *xcf, FULL_LENGTH *xrb,
+  FULL_LENGTH *xrf, OBJECT y, FULL_LENGTH theta)
+{ rect_coord ycorners[4], xcorner;  polar_coord pol;
+  double maxx, maxy, minx, miny, ang;  int i;
+#if DEBUG_ON
+  char buff1[20], buff2[20];
+#endif
+
+  /* calculate theta in radians */
+  ang = (double) theta * 2 * M_PI / (double) (DG * 360);
+  ifdebug(DRS, D, sprintf(buff2, "%.1f", ang));
+  debug2(DRS, D, "RotateSize( %s, %s )", EchoObject(y), buff2);
+  debug4(DRS, DD, "  ycb %s, ycf %s, yrb %s, yrf %s",
+	EchoLength(back(y, COLM)), EchoLength(fwd(y, COLM)),
+	EchoLength(back(y, ROWM)), EchoLength(fwd(y, ROWM)));
+
+  /* set up coordinates of the four corners of y */
+  ycorners[0].x =   (float) fwd(y, COLM);
+  ycorners[0].y =   (float) back(y, ROWM);
+  ycorners[1].x = - (float) back(y, COLM);
+  ycorners[1].y =   (float) back(y, ROWM);
+  ycorners[2].x = - (float) back(y, COLM);
+  ycorners[2].y = - (float) fwd(y, ROWM);
+  ycorners[3].x =   (float) fwd(y, COLM);
+  ycorners[3].y = - (float) fwd(y, ROWM);
+
+  /* rotate these four corners by theta and store their extremes */
+  maxx = maxy = (float) - MAX_FULL_LENGTH;
+  minx = miny = (float) MAX_FULL_LENGTH;
+  for( i = 0;  i < 4;  i++ )
+  {	
+    if( ycorners[i].x == 0 && ycorners[i].y == 0 )
+    {	pol.radius = 0; pol.angle  = 0; }
+    else rect_to_polar(ycorners[i], pol);
+    ifdebug(DRS, DD, sprintf(buff1, "%.1f", pol.angle));
+    ifdebug(DRS, DD, sprintf(buff2, "%.1f", ang));
+    debug5(DRS, DD, "  transforming (%s, %s) -> (%s, %s) + %s",
+      EchoLength( (int) ycorners[i].x), EchoLength( (int) ycorners[i].y),
+      EchoLength( (int) pol.radius), buff1, buff2);
+    pol.angle += ang;
+    polar_to_rect(pol, xcorner);
+    ifdebug(DRS, DD, sprintf(buff1, "%.1f", pol.angle));
+    debug4(DRS, DD, "    transforming (%s, %s) -> (%s, %s)",
+      EchoLength( (int) pol.radius), buff1,
+      EchoLength( (int) xcorner.x), EchoLength( (int) xcorner.y) );
+    maxx = find_max(maxx, xcorner.x);    minx = find_min(minx, xcorner.x);
+    maxy = find_max(maxy, xcorner.y);    miny = find_min(miny, xcorner.y);
+  }
+
+  /* store sizes back into x and return */
+  *xcb = - (int) minx;    *xcf  =   (int) maxx;
+  *xrb =   (int) maxy;    *xrf  = - (int) miny;
+  debug0(DRS, D, "RotateSize returning.");
+  debug4(DRS, DD, "  xcb %s, xcf %s, xrb %s, xrf %s",
+    EchoLength(*xcb), EchoLength(*xcf),
+    EchoLength(*xrb), EchoLength(*xrf));
+} /* end RotateSize */