[Teem-commit] teem/src/ell/test inter.c,NONE,1.1

[Gordon K. <kin...@us...>]

Update of /cvsroot/teem/teem/src/ell/test
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv8743/test

Added Files:
	inter.c 
Log Message:
recreates a college physics demonstration of the interference inherent in a diffraction grating

--- NEW FILE: inter.c ---
/*
  teem: Gordon Kindlmann's research software
  Copyright (C) 2004, 2003, 2002, 2001, 2000, 1999, 1998 University of Utah

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "../ell.h"

char *interInfo = ("Recreates memories of college physics");

typedef struct {
  FILE *file;
  double psc;
  double bbox[4];
  
  double maxX, maxY, yscale;
} wheelPS;

#define WPS_X(x) AIR_AFFINE(wps->bbox[0], (x), wps->bbox[2], 0, wps->maxX)
#define WPS_Y(y) AIR_AFFINE(wps->bbox[1], (y), wps->bbox[3], 0, wps->maxY)
#define WPS_S(s)  AIR_DELTA(wps->bbox[1], (s), wps->bbox[3], 0, wps->maxY)

void
wheelPreamble(wheelPS *wps) {

  wps->maxX = wps->psc*(wps->bbox[2] - wps->bbox[0]);
  wps->maxY = wps->psc*(wps->bbox[3] - wps->bbox[1]);

  fprintf(wps->file, "%%!PS-Adobe-2.0 EPSF-2.0\n");
  fprintf(wps->file, "%%%%Creator: limn\n");
  fprintf(wps->file, "%%%%Pages: 1\n");
  fprintf(wps->file, "%%%%BoundingBox: 0 0 %d %d\n", 
	  (int)(wps->maxX),
	  (int)(wps->maxY));
  fprintf(wps->file, "%%%%EndComments\n");
  fprintf(wps->file, "%%%%EndProlog\n");
  fprintf(wps->file, "%%%%Page: 1 1\n");
  fprintf(wps->file, "gsave\n");
  fprintf(wps->file, "0 0 moveto\n");
  fprintf(wps->file, "%g 0 lineto\n", wps->maxX);
  fprintf(wps->file, "%g %g lineto\n", wps->maxX, wps->maxY);
  fprintf(wps->file, "0 %g lineto\n", wps->maxY);
  fprintf(wps->file, "closepath\n");
  fprintf(wps->file, "clip\n");
  fprintf(wps->file, "gsave newpath\n");
  fprintf(wps->file, "1 setlinejoin\n");
  fprintf(wps->file, "1 setlinecap\n");
  fprintf(wps->file, "/M {moveto} bind def\n");
  fprintf(wps->file, "/L {lineto} bind def\n");
  fprintf(wps->file, "/W {setlinewidth} bind def\n");
  fprintf(wps->file, "/F {fill} bind def\n");
  fprintf(wps->file, "/S {stroke} bind def\n");
  fprintf(wps->file, "/CP {closepath} bind def\n");
  fprintf(wps->file, "/RGB {setrgbcolor} bind def\n");
  fprintf(wps->file, "/Gr {setgray} bind def\n");
  fprintf(wps->file, "\n");
  return;
}

void
wheelWidth(wheelPS *wps, double width) {

  fprintf(wps->file, "%g W\n", width);
  return;
}

void
wheelGray(wheelPS *wps, double gray) {

  fprintf(wps->file, "%g Gr\n", gray);
  return;
}

void
wheelArrow(wheelPS *wps, double x0, double y0, double x1, double y1,
	   double alen, double awidth) {
  double len, dir[2], perp[2];
  
  dir[0] = x0 - x1;
  dir[1] = y0 - y1;
  ELL_2V_NORM(dir, dir, len);
  ELL_2V_SET(perp, -dir[1], dir[0]);
  fprintf(wps->file, "%g %g M\n", WPS_X(x0), WPS_Y(y0));
  fprintf(wps->file, "%g %g L S\n",
	  WPS_X(x1 + alen*dir[0]/2), 
	  WPS_Y(y1 + alen*dir[1]/2));
  if (alen && awidth) {
    if (len < alen) {
      awidth *= len/alen;
      alen = len;
    }
    fprintf(wps->file, "%g %g M\n", 
	    WPS_X(x1 + alen*dir[0] + awidth*perp[0]), 
	    WPS_Y(y1 + alen*dir[1] + awidth*perp[1]));
    fprintf(wps->file, "%g %g L\n", WPS_X(x1), WPS_Y(y1));
    fprintf(wps->file, "%g %g L CP F\n", 
	    WPS_X(x1 + alen*dir[0] - awidth*perp[0]), 
	    WPS_Y(y1 + alen*dir[1] - awidth*perp[1]));
  }
  return;
}

void
wheelEpilog(wheelPS *wps) {

  fprintf(wps->file, "grestore\n");
  fprintf(wps->file, "grestore\n");
  fprintf(wps->file, "%%%%Trailer\n");
  return;
}

int
main(int argc, char *argv[]) {
  char *me, *outS;
  hestOpt *hopt;
  hestParm *hparm;
  airArray *mop;
  
  int fidx, aidx, num, frames;
  double psc, width[2], arrowWidth, lineWidth, angle, seglen,
    x0, y0, x1, y1, cc, ss;
  wheelPS wps;
  char filename[AIR_STRLEN_MED];

  me = argv[0];
  mop = airMopNew();
  hparm = hestParmNew();
  hparm->elideMultipleNonExistFloatDefault = AIR_TRUE;
  hopt = NULL;
  airMopAdd(mop, hparm, (airMopper)hestParmFree, airMopAlways);
  hestOptAdd(&hopt, "w", "arrowWidth lineWidth", airTypeDouble, 2, 2, width, 
	     "1.0 0.2", "widths");
  hestOptAdd(&hopt, "n", "number", airTypeInt, 1, 1, &num, "10",
	     "number of arrows");
  hestOptAdd(&hopt, "f", "frames", airTypeInt, 1, 1, &frames, "10",
	     "number of frames");
  hestOptAdd(&hopt, "psc", "scale", airTypeDouble, 1, 1, &psc, "200",
	     "scaling from world space to PostScript points");
  hestOptAdd(&hopt, "o", "prefix", airTypeString, 1, 1, &outS, NULL,
	     "prefix of file names");
  hestParseOrDie(hopt, argc-1, argv+1, hparm,
		 me, interInfo, AIR_TRUE, AIR_TRUE, AIR_TRUE);
  airMopAdd(mop, hopt, (airMopper)hestOptFree, airMopAlways);
  airMopAdd(mop, hopt, (airMopper)hestParseFree, airMopAlways);

  for (fidx=0; fidx<frames; fidx++) {
    sprintf(filename, "%s%03d.eps", outS, fidx);
    if (!(wps.file = airFopen(filename, stdout, "wb"))) {
      fprintf(stderr, "%s: couldn't open output file\n", me);
      airMopError(mop); return 1;
    }
    
    lineWidth = width[0];
    arrowWidth = width[1];
    wps.psc = psc;
    ELL_4V_SET(wps.bbox, -0.45, -0.85, 1.1, 0.85);
    wheelPreamble(&wps);

    fprintf(wps.file, "0 setlinecap\n");
    
    wheelGray(&wps, 0.4);
    wheelWidth(&wps, lineWidth);
    
    x0 = 0;
    y0 = 0;
    seglen = 1.0/num;
    angle = AIR_AFFINE(0, fidx, frames, 0, 2*AIR_PI);
    for (aidx=1; aidx<=num; aidx++) {
      cc = cos(angle*aidx)*seglen;
      ss = sin(angle*aidx)*seglen;
      x1 = x0 + 0.90*cc;
      y1 = y0 + 0.90*ss;
      wheelArrow(&wps, x0, y0, x1, y1, arrowWidth, arrowWidth*0.4);
      x0 += cc;
      y0 += ss;
    }

    wheelGray(&wps, 0.0);
    wheelArrow(&wps, 0, 0, x0, y0, arrowWidth, arrowWidth*0.4);
    
    wheelEpilog(&wps);
    airFclose(wps.file);
  }

  airMopOkay(mop);
  exit(0);
}


/*
mkdir inter04
test/inter -w 4 0.08 -o inter04/ -n 4 -f 300

mkdir inter08
test/inter -w 2.5 0.04 -o inter08/ -n 8 -f 300

mkdir inter16
test/inter -w 2.2 0.02 -o inter16/ -n 16 -f 300

mkdir inter32
test/inter -w 2 0.01 -o inter32/ -n 32 -f 300

mkdir inter

foreach I ( 000 001 002 003 004 005 006 007 008 009 \
            010 011 012 013 014 015 016 017 018 019 \
            020 021 022 023 024 025 026 027 028 029 \
            030 031 032 033 034 035 036 037 038 039 \
            040 041 042 043 044 045 046 047 048 049 \
            050 051 052 053 054 055 056 057 058 059 \
            060 061 062 063 064 065 066 067 068 069 \
            070 071 072 073 074 075 076 077 078 079 \
            080 081 082 083 084 085 086 087 088 089 \
            090 091 092 093 094 095 096 097 098 099 \
            100 101 102 103 104 105 106 107 108 109 \
            110 111 112 113 114 115 116 117 118 119 \
            120 121 122 123 124 125 126 127 128 129 \
            130 131 132 133 134 135 136 137 138 139 \
            140 141 142 143 144 145 146 147 148 149 \
            150 151 152 153 154 155 156 157 158 159 \
            160 161 162 163 164 165 166 167 168 169 \
            170 171 172 173 174 175 176 177 178 179 \
            180 181 182 183 184 185 186 187 188 189 \
            190 191 192 193 194 195 196 197 198 199 \
            200 201 202 203 204 205 206 207 208 209 \
            210 211 212 213 214 215 216 217 218 219 \
            220 221 222 223 224 225 226 227 228 229 \
            230 231 232 233 234 235 236 237 238 239 \
            240 241 242 243 244 245 246 247 248 249 \
            250 251 252 253 254 255 256 257 258 259 \
            260 261 262 263 264 265 266 267 268 269 \
            270 271 272 273 274 275 276 277 278 279 \
            280 281 282 283 284 285 286 287 288 289 \
            290 291 292 293 294 295 296 297 298 299 )
  echo $I
  foreach J ( 04 08 16 32 )
    eps2ppm inter{$J}/${I}.eps 250 \
     | unu slice -a 0 -p 0 \
     | unu resample -s x0.2 x0.2 -o inter${J}/${I}.png
  end
  unu pad -i inter04/${I}.png -min 0 0 -max M+1 M -b pad -v 128 \
   | unu join -i - inter08/${I}.png -a 0 \
   | unu pad -min 0 0 -max M M+1 -b pad -v 128 -o a.png
  unu pad -i inter16/${I}.png -min 0 0 -max M+1 M -b pad -v 128 \
   | unu join -i - inter32/${I}.png -a 0 -o b.png
  unu join -i a.png b.png -a 1 \
   | unu 2op - 255 - -o inter/${I}.png
end

rm -f a.png b.png

*/