Attachment 'ap02.c'

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   1 // ap02.c
   2 // cc -o ap02 ap02.c -lgd -lpng -lm
   3 // 
   4 // Apogee skew   Keith Lofstrom  May 12, 2009
   5 //
   6 // FIXED ... apogee skew 
   7 // at the semiminor points TOWARDS apogee
   8 //
   9 // Uses the libgd library.  For documentation see the file:
  10 //     /usr/share/doc/gd-*/index.html  
  11 // or the website:
  12 //     http://www.libgd.org/Reference
  13 
  14 #define  RMMKDIR    "rm -rf ap02dir ; mkdir ap02dir"
  15 #define  PNGFMT     "ap02dir/a%04d.png"
  16 #define  PNG2SWF    "png2swf -o ap02.swf -r 20 ap02dir/*.png" 
  17 #define  XSIZE      1000
  18 #define  YSIZE       600
  19 #define  YCENTER     360
  20 #define  SPACE        60
  21 #define  SIZE         20
  22 #define  NUM          25
  23 #define  NUMX          5
  24 #define  NPICS       200
  25 #define  ESIZE        90
  26 #define  ORBSIZE      90
  27 #define  SSIZE        20
  28 #define  ZFACTR      0.1
  29 #define  LAYER       0.8
  30 #define  PSIZE         6
  31 #define  TOP         100
  32 #define  FNT        "DejaVuMonoSans"
  33 #define  FSZ          40
  34 #define  ASCALE      2.0
  35 
  36 #include <gd.h>
  37 #include <math.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 
  41 int  sun1, white, red, green, blue     ; //  color indexes 
  42 int  dred, gray, trans, lgray, cyan    ;
  43 int  dgray, yellow, magenta, black     ; 
  44 int  dcyan                             ;
  45 int     carr[2*NUM];
  46 double  xarr[NUM];
  47 double  yarr[NUM];
  48 double  zarr[NUM];
  49 double  xdis[NUM];  // scaled and translated x
  50 double  wdis[NUM];  // unscaled y
  51 double  ydis[NUM];  // scaled and translated y
  52 double  zdis[NUM];  // unscaled z
  53 double  xcenter = XSIZE / 2 ;
  54 double  ycenter = YCENTER ;
  55 int     ex      = (int) (1.5*ORBSIZE) ;
  56 int     ey      = (int) (1.5*ORBSIZE) ;
  57 int     re      = ESIZE / 2 ;
  58 
  59 double     pi2    = 6.283185307 ;
  60 gdImagePtr im;                          // Declare the image
  61 FILE       *pngout;                     // Declare output file
  62 
  63 // define colors -----------------------------------------------------------
  64 #define  CMAX      240
  65 #define  CSTEP     30
  66 #define  CCNT      5
  67 void  colorstart() {
  68    int    cp, cq,  ix, ired, igreen, iblue ;
  69    white   =gdImageColorAllocate (im, 255, 255, 255);
  70    black   =gdImageColorAllocate (im,   0,   0,   0);
  71    gray    =gdImageColorAllocate (im, 128, 128, 128);
  72    dgray   =gdImageColorAllocate (im,  96,  96,  96);
  73    lgray   =gdImageColorAllocate (im, 192, 192, 192);
  74    cyan    =gdImageColorAllocate (im,   0, 192, 192);
  75    dcyan   =gdImageColorAllocate (im,   0,  48,  48);
  76    red     =gdImageColorAllocate (im, 255,   0,   0);
  77    dred    =gdImageColorAllocate (im, 128,   0,   0);
  78    yellow  =gdImageColorAllocate (im, 255, 255,   0);
  79    green   =gdImageColorAllocate (im,   0, 255,   0);
  80    blue    =gdImageColorAllocate (im,   0,   0, 255);
  81    magenta =gdImageColorAllocate (im, 192,   0, 192);
  82    trans   =gdImageColorAllocate (im,   1,   1,   1);
  83 
  84    for( cp=0 ; cp < CCNT ; cp++ ) {
  85       for( cq=0 ; cq < CCNT ; cq++ ) {
  86          ix     = CCNT*cp+cq ;
  87          ired   = CMAX - CSTEP*( cp + cq ) ;
  88          igreen = 2*CSTEP * cp ;
  89          iblue  = 2*CSTEP * cq ;
  90          carr[    ix] = gdImageColorAllocate(im, ired  , igreen  , iblue  );
  91          carr[NUM+ix] = gdImageColorAllocate(im, ired/2, igreen/2, iblue/2);
  92       }
  93    }
  94 }
  95 
  96 // set up array positions ---------------------------------------------------
  97 void  astart() {
  98    int     ap, aq, ai ;
  99    double  n = (double) NUM ;
 100    double n2 = sqrt( n ) ;
 101    int    ni = (int) n2 ;
 102    double nm = 0.5*(n2-1.0) ;
 103 
 104    for( ap=0 ; ap < ni ; ap++ ) {
 105       for( aq=0 ; aq < ni ; aq++ ) {
 106          ai = ni * ap + aq ;
 107          zarr[ai] = ((double) ap ) - nm ;
 108          yarr[ai] = ((double) aq ) - nm ;
 109          xarr[ai] = 0.0                 ;
 110       }    
 111    }  
 112    carr[NUM-1]=white ;
 113 }  
 114 
 115 // draw arrowhead (either degrees or radians ) -----------------------------
 116 void arrowhead( double xp, double yp, double asize,
 117                 double deg, double rad, int color ) {
 118    double angl = rad+pi2*deg/360.0 ;
 119    gdPoint arrow[3] ;
 120 
 121    arrow[0].x = (int)(xp);
 122    arrow[0].y = (int)(yp);
 123    arrow[1].x = (int)(xp+asize*(    -cos(angl)-0.5*sin(angl)));
 124    arrow[1].y = (int)(yp+asize*( 0.5*cos(angl)-    sin(angl)));
 125    arrow[2].x = (int)(xp+asize*(    -cos(angl)+0.5*sin(angl)));
 126    arrow[2].y = (int)(yp+asize*(-0.5*cos(angl)-    sin(angl)));
 127    gdImageFilledPolygon( im, arrow, 3, color );
 128 }
 129 
 130 // draw arrow  -------------------------------------------------------------
 131 void arrow( double x0, double y0, double x1, double y1, int color ) {
 132    double  asize = 0.02*(x1-x0) ;
 133 
 134    gdImageLine( im, (int)x0, (int)y0, (int)x1, (int)y1, color ) ;
 135    arrowhead( x1, y1, 0.02*(x1-x0), 0.0, 0.0, color ) ;
 136 }
 137 
 138 
 139 // draw rotating earth and orbiting body and side arrow  -------------
 140 
 141 void earth( double ang ) {
 142    double  x,  y  ;
 143    double  xs, ys ;
 144    int  x0, y0 ;
 145    int  x1, y1 ;
 146    double  an0 ;
 147    int i    ;
 148    int xcnt ;
 149    int orbit = 2*ORBSIZE ;
 150 
 151    gdImageFilledArc(im, ex, ey, ESIZE, ESIZE,   0, 360, dcyan, gdArc);
 152    gdImageFilledArc(im, ex, ey, ESIZE, ESIZE,  90, 270,  cyan, gdArc);
 153    gdImageArc(      im, ex, ey, orbit, orbit,  30, 330, white );
 154    gdImageArc(      im, ex, ey, orbit, orbit, 330,  30, dgray );
 155 
 156    // draw longitude lines  ( 6 = 180/30 degrees )
 157    for( i=0 ; i < 6 ; i++ ) {
 158       an0 = (ang/6.0) + pi2*( (double) i ) / 12.0 ;
 159       x0  = ex - (int)( ((double)re) * cos(an0 ));
 160       x1  = ex + (int)( ((double)re) * cos(an0 ));
 161       y0  = ey + (int)( ((double)re) * sin(an0 ));
 162       y1  = ey - (int)( ((double)re) * sin(an0 ));
 163       gdImageLine( im, x0, y0, x1, y1, black );
 164    }
 165 
 166    // draw latitude lines
 167    for( i=1 ; i < 3 ; i++ ) {
 168       an0 = pi2*( (double) i ) / 12.0 ;
 169       x0  = (int)( 2.0 * ((double)re) * cos(an0) );
 170       gdImageArc( im, ex, ey, x0, x0, 0, 360, black );
 171    }
 172    
 173    // draw arrowhead to show side point of view
 174    x= -ORBSIZE - 2.0*PSIZE ;
 175    y=  0.0 ;
 176    xs = x*cos(ang)+y*sin(ang) + (double) ex ;
 177    ys = y*cos(ang)-x*sin(ang) + (double) ey ;
 178  
 179    arrowhead( xs, ys, 2*PSIZE,  0.0, -ang, white );
 180 }
 181 
 182 // ========================================================================
 183 
 184 int main() {
 185    double  angle ;
 186    int     i     ;
 187    int     xcnt  ;
 188    int     frame ;
 189    char    pngfilename[64];
 190 
 191    double  test   ;   // depth testing
 192    int     ox, oy ;
 193    int     s0     ;
 194 
 195    double  xu, yu ;
 196    int     xi, yi ;
 197    int     icol   ;
 198    double  deg    ; 
 199 
 200    system( RMMKDIR );
 201 
 202    for( frame = 0 ; frame < NPICS ; frame++ ) {
 203       im = gdImageCreateTrueColor(XSIZE, YSIZE );
 204       sprintf( pngfilename,  PNGFMT, frame );
 205       pngout = fopen( pngfilename, "wb");
 206 
 207       angle = frame * pi2 / NPICS ;
 208       colorstart() ;
 209       astart()     ;
 210       earth(angle) ;
 211 
 212       //  labels -----------------------------------------------------------
 213 
 214       gdImageStringFT( im, NULL,                       // imagespace, bounding 
 215                        white, FNT, FSZ,                // color, font, fontsize
 216                        0.0, 0.00*XSIZE, 0.98*YSIZE,    // angle, x, y
 217                        " Side View" );                 // the text
 218 
 219       gdImageStringFT( im, NULL,                       // imagespace, bounding
 220                        white, FNT, FSZ/2,              // color, font, fontsize
 221                        0.0, 0.25*XSIZE, 0.27*YSIZE,    // angle, x, y
 222 		       "    Top View" );               // the text
 223 
 224       gdImageStringFT( im, NULL,                       // imagespace, bounding
 225                        white, FNT, FSZ/2,              // color, font, fontsize
 226                        0.0, 0.50*XSIZE, 0.27*YSIZE,    // angle, x, y
 227 		       " Front View" );                // the text
 228 
 229       gdImageStringFT( im, NULL,                       // imagespace, bounding
 230                        white, FNT, FSZ/2,              // color, font, fontsize
 231                        0.0, 0.71*XSIZE, 0.27*YSIZE,    // angle, x, y
 232 		       "   Side View" );               // the text
 233 
 234       //  time code -------------------------------------------------------
 235  
 236       double time0 = ( 4.0 * (double) frame ) / ( (double) NPICS ) ;
 237       char   timestring[64] ;
 238 
 239       sprintf( timestring, "%3.1f/4.0 hours, 1440x speedup", time0 );
 240 
 241       gdImageStringFT( im, NULL,                       // imagespace, bounding 
 242                        white, FNT, 0.6*FSZ,            // color, font, fontsize
 243                        0.0, XSIZE-14.0*FSZ,            // angle, x
 244                        0.98*YSIZE, timestring );       // y, the text 
 245 
 246       //  direction arrows ------------------------------------------------
 247 
 248       arrow( 0.00*XSIZE,      ycenter, 0.96*XSIZE,      ycenter, lgray );
 249       arrow( 0.26*XSIZE, 0.25*ycenter, 0.50*XSIZE, 0.25*ycenter, lgray );
 250       arrow( 0.71*XSIZE, 0.25*ycenter, 0.95*XSIZE, 0.25*ycenter, lgray );
 251 
 252       //  draw main view from top ----------------------------------------
 253       for( i=0 ; i < NUM ; i++ ) {
 254          zdis[i] =-cos(angle)*zarr[i]-sin(angle)*yarr[i] ;
 255          wdis[i] = cos(angle)*yarr[i]-sin(angle)*zarr[i];
 256          ydis[i] = ycenter - SPACE*wdis[i];
 257          xdis[i] = xcenter + SPACE*(2.0*zdis[i]-0.5*NUMX) ;
 258       }
 259 
 260 
 261       for( test = -5.0*LAYER ; test < 5.0*LAYER ; test += LAYER ) {
 262          for( i=0 ; i < NUM ; i++ ) {
 263             for( xcnt = 0 ; xcnt < NUMX ; xcnt++ ) {
 264                if( ( zdis[i] >= test ) && ( zdis[i] < ( test+LAYER ) ) ) {
 265 
 266                   // small top view
 267                   s0 = (int) ( 0.35*SIZE * (1.00 + ZFACTR * zdis[i] ) ) ;
 268                   ox = (int) ( 0.26*XSIZE + 0.25*(SPACE*xcnt+xdis[i]) );
 269                   oy = (int) ( 0.25*ydis[i] );
 270                   gdImageFilledArc(im, ox, oy, s0, s0, 0, 360, carr[i], gdArc);
 271    
 272                   // draw points in top orbit representation
 273 
 274                   xu = -ORBSIZE - ASCALE * wdis[i] ;
 275                   yu =  ASCALE * ( ((double)xcnt) + 2.0*zdis[i]-0.5*NUMX );
 276 
 277                   xi = ex + (int)( xu*cos(angle)+yu*sin(angle)) ;
 278                   yi = ey + (int)( yu*cos(angle)-xu*sin(angle)) ;
 279 
 280 		  if(  ( xi <   ex      ) 
 281                      ||( yi < ( ey-re ) )
 282                      ||( yi > ( ey+re ) ) ) icol = carr[    i];
 283                   else                      icol = carr[NUM+i];
 284 
 285                   gdImageFilledArc( im, xi, yi, 3, 3, 0, 360, icol, gdArc );
 286                }
 287 
 288                if( ( wdis[i] >= test ) && ( wdis[i] < ( test+LAYER ) ) ) {
 289                   // main side view
 290                   s0 = (int) (      SIZE * (1.00 + ZFACTR * wdis[i] ) ) ;
 291                   ox = (int) ( SPACE*xcnt+xdis[i]);
 292                   oy = (int) ( ycenter-SPACE*zdis[i])  ;
 293                   gdImageFilledArc(im, ox, oy, s0, s0, 0, 360, carr[i], gdArc);
 294 
 295                   // small side view  
 296                   s0 = (int) ( 0.35*SIZE * (1.00 + ZFACTR * wdis[i] ) ) ;
 297                   ox = (int) ( 0.71*XSIZE + 0.25*(SPACE*xcnt+xdis[i]));
 298                   oy = (int) ( 0.25*(ycenter-SPACE*zdis[i]) ) ;
 299                   gdImageFilledArc(im, ox, oy, s0, s0, 0, 360, carr[i], gdArc);
 300                }
 301             }
 302 
 303             // small front view - apogee to left, closer
 304             s0 = (int) ( 0.35*SIZE * (1.30 + 2.0* ZFACTR * zdis[i] ) ) ;
 305 	    ox = (int) ( 0.60*XSIZE - 0.25*SPACE*wdis[i]   );
 306 	    oy = (int) ( 0.25*( ycenter   -SPACE*zdis[i] ) );
 307             gdImageFilledArc(im, ox, oy, s0, s0, 0, 360, carr[i], gdArc);
 308          }
 309       }
 310 
 311       /* Output the frame in PNG format. */
 312       gdImagePngEx( im, pngout, 1 );
 313       gdImageDestroy(im);
 314       fclose(pngout);
 315    }
 316 
 317    system( PNG2SWF );
 318 }

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  • [get | view] (2009-05-12 03:45:56, 11.6 KB) [[attachment:ap01.c]]
  • [get | view] (2009-05-12 20:57:15, 11.1 KB) [[attachment:ap02.c]]
  • [get | view] (2009-05-12 20:57:44, 4323.3 KB) [[attachment:ap02.swf]]
  • [get | view] (2009-05-11 08:39:41, 1.4 KB) [[attachment:t01.c]]
  • [get | view] (2009-05-11 02:49:58, 14.3 KB) [[attachment:t01.gif]]
  • [get | view] (2009-05-11 08:39:31, 4.0 KB) [[attachment:t04.c]]
  • [get | view] (2009-05-11 02:50:13, 24.3 KB) [[attachment:t04.gif]]
  • [get | view] (2009-05-11 08:39:10, 4.0 KB) [[attachment:t08.c]]
  • [get | view] (2009-05-11 02:50:25, 29.6 KB) [[attachment:t08.gif]]
  • [get | view] (2009-05-11 02:53:25, 34.8 KB) [[attachment:t12.gif]]
  • [get | view] (2009-05-11 08:38:55, 4.0 KB) [[attachment:t16.c]]
  • [get | view] (2009-05-11 02:53:12, 38.0 KB) [[attachment:t16.gif]]
  • [get | view] (2009-05-11 08:38:44, 4.0 KB) [[attachment:t20.c]]
  • [get | view] (2009-05-11 02:52:57, 39.6 KB) [[attachment:t20.gif]]
  • [get | view] (2009-05-11 08:38:32, 4.0 KB) [[attachment:t24.c]]
  • [get | view] (2009-05-11 02:52:39, 44.0 KB) [[attachment:t24.gif]]
  • [get | view] (2009-05-11 08:37:48, 4.0 KB) [[attachment:t25.c]]
  • [get | view] (2009-05-11 02:52:29, 41.5 KB) [[attachment:t25.gif]]
  • [get | view] (2009-05-11 08:38:21, 3.4 KB) [[attachment:t26.c]]
  • [get | view] (2009-05-11 02:52:12, 28.0 KB) [[attachment:t26.gif]]
  • [get | view] (2009-05-11 08:37:25, 2.5 KB) [[attachment:t27.c]]
  • [get | view] (2009-05-11 02:51:59, 25.8 KB) [[attachment:t27.gif]]
  • [get | view] (2009-05-11 08:37:13, 2.5 KB) [[attachment:t28.c]]
  • [get | view] (2009-05-11 02:51:34, 18.5 KB) [[attachment:t28.gif]]
  • [get | view] (2009-05-11 08:37:01, 1.4 KB) [[attachment:t41.c]]
  • [get | view] (2009-05-11 02:51:19, 11.4 KB) [[attachment:t41.gif]]
  • [get | view] (2009-05-11 08:36:46, 3.6 KB) [[attachment:t42.c]]
  • [get | view] (2009-05-11 02:50:49, 5.3 KB) [[attachment:t42.gif]]
  • [get | view] (2009-05-11 08:36:31, 13.4 KB) [[attachment:tor00.hc]]
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