| fe4da5cc |
1 | * |
| 2 | * $Id$ |
| 3 | * |
| 4 | * $Log$ |
| 5 | * Revision 1.1.1.1 1995/10/24 10:20:53 cernlib |
| 6 | * Geant |
| 7 | * |
| 8 | * |
| 9 | #include "geant321/pilot.h" |
| 10 | *CMZ : 3.21/02 29/03/94 15.41.30 by S.Giani |
| 11 | *-- Author : |
| 12 | SUBROUTINE GNOTRA (X, PAR, IACT, IFLAG, SNEXT, SNXT, SAFE) |
| 13 | C. |
| 14 | C. ****************************************************************** |
| 15 | C. * * |
| 16 | C. * COMPUTE DISTANCE UP TO INTERSECTION WITH 'TRD1' OR 'TRD2' * |
| 17 | C. * VOLUME, FROM OUTSIDE POINT X(1-3) ALONG DIRECTION X(4-6) * |
| 18 | C. * * |
| 19 | C. * PAR (input) : volume parameters * |
| 20 | C. * IACT (input) : action flag * |
| 21 | C. * = 0 Compute SAFE only * |
| 22 | C. * = 1 Compute SAFE, and SNXT only if SNEXT .GT.new SAFE * |
| 23 | C. * = 2 Compute both SAFE and SNXT * |
| 24 | C. * = 3 Compute SNXT only * |
| 25 | C. * IFLAG (input) : = 1 for TRD1, 2 for TRD2 * |
| 26 | C. * SNEXT (input) : see IACT = 1 * |
| 27 | C. * SNXT (output) : distance to volume boundary * |
| 28 | C. * SAFE (output) : shortest distance to any boundary * |
| 29 | C. * * |
| 30 | C. * ==>Called by : GNEXT, GTNEXT * |
| 31 | C. * Author A.McPherson, P.Weidhaas ********* * |
| 32 | C. * * |
| 33 | C. ****************************************************************** |
| 34 | C. |
| 35 | #include "geant321/gconsp.inc" |
| 36 | DIMENSION X(6),PAR(5) |
| 37 | C. |
| 38 | C. ---------------------------------------------------------------- |
| 39 | C. |
| 40 | |
| 41 | SNXT = BIG |
| 42 | IF (IFLAG .EQ. 1) THEN |
| 43 | FACTX = (PAR(2) - PAR(1)) / (2.0*PAR(4)) |
| 44 | ELSEIF (IFLAG .EQ. 2) THEN |
| 45 | FACTX = (PAR(2) - PAR(1)) / (2.0*PAR(5)) |
| 46 | FACTY = (PAR(4) - PAR(3)) / (2.0*PAR(5)) |
| 47 | ENDIF |
| 48 | |
| 49 | IF (IACT .LT. 3) THEN |
| 50 | |
| 51 | C ------------------------------------------------- |
| 52 | C | Compute safety-distance 'SAFE' (P.Weidhaas) | |
| 53 | C ------------------------------------------------- |
| 54 | |
| 55 | IF (IFLAG .EQ. 1) THEN |
| 56 | C******************************************************* |
| 57 | C |
| 58 | C...... Shape "TRD1": only x varies with z. |
| 59 | C |
| 60 | C******************************************************* |
| 61 | |
| 62 | SAF2 = MAX (ABS(X(2)) - PAR(3), 0.0) |
| 63 | SAF3 = MAX (ABS(X(3)) - PAR(4), 0.0) |
| 64 | C |
| 65 | C...... Distance along x-direction to slanted wall. |
| 66 | C |
| 67 | DISTX = PAR(1) + FACTX * (PAR(4) + X(3)) |
| 68 | IF (ABS(X(1)) .GT. DISTX) THEN |
| 69 | SAF1 = (ABS(X(1)) - DISTX) / SQRT(1.0 + FACTX*FACTX) |
| 70 | ELSE |
| 71 | SAF1 = 0.0 |
| 72 | ENDIF |
| 73 | |
| 74 | |
| 75 | ELSE |
| 76 | C******************************************************* |
| 77 | C |
| 78 | C...... Shape "TRD2": both x and y vary with z. |
| 79 | C |
| 80 | C******************************************************* |
| 81 | |
| 82 | SAF3 = MAX (ABS(X(3)) - PAR(5), 0.0) |
| 83 | |
| 84 | C |
| 85 | C...... Distance along x-direction to slanted wall. |
| 86 | C |
| 87 | DISTX = PAR(1) + FACTX * (PAR(5) + X(3)) |
| 88 | IF (ABS(X(1)) .GT. DISTX) THEN |
| 89 | SAF1 = (ABS(X(1)) - DISTX) / SQRT(1.0 + FACTX*FACTX) |
| 90 | ELSE |
| 91 | SAF1 = 0.0 |
| 92 | ENDIF |
| 93 | C |
| 94 | C...... Distance along y-direction to slanted wall. |
| 95 | C |
| 96 | DISTY = PAR(3) + FACTY * (PAR(5) + X(3)) |
| 97 | IF (ABS(X(2)) .GT. DISTY) THEN |
| 98 | SAF2 = (ABS(X(2)) - DISTY) / SQRT(1.0 + FACTY*FACTY) |
| 99 | ELSE |
| 100 | SAF2 = 0.0 |
| 101 | ENDIF |
| 102 | |
| 103 | ENDIF |
| 104 | |
| 105 | SAFE = MAX (SAF1, SAF2, SAF3) |
| 106 | |
| 107 | IF (IACT .EQ. 0) GO TO 999 |
| 108 | IF (IACT .EQ. 1) THEN |
| 109 | IF (SNEXT .LT. SAFE) GO TO 999 |
| 110 | ENDIF |
| 111 | ENDIF |
| 112 | |
| 113 | |
| 114 | C ------------------------------------------------ |
| 115 | C | Compute vector-distance 'SNXT' (McPherson) | |
| 116 | C ------------------------------------------------ |
| 117 | |
| 118 | |
| 119 | C |
| 120 | C Only x varies with z. |
| 121 | C |
| 122 | IF(IFLAG.NE.1) GO TO 50 |
| 123 | S3=PAR(4) |
| 124 | FACTX = (PAR(2) - PAR(1)) / (2.0*S3) |
| 125 | S1 = 0.5 * (PAR(1) + PAR(2)) + FACTX * X(3) |
| 126 | DS11=X(4) - FACTX * X(6) |
| 127 | DS12=X(4) + FACTX * X(6) |
| 128 | S2=PAR(3) |
| 129 | DS21=X(5) |
| 130 | DS22=X(5) |
| 131 | GO TO 60 |
| 132 | C |
| 133 | C Both x and y widths vary with z. |
| 134 | C |
| 135 | 50 CONTINUE |
| 136 | S3=PAR(5) |
| 137 | FACTX = (PAR(2) - PAR(1)) / (2.0*S3) |
| 138 | FACTY = (PAR(4) - PAR(3)) / (2.0*S3) |
| 139 | S1 = 0.5 * (PAR(1) + PAR(2)) + FACTX * X(3) |
| 140 | DS11=X(4) - FACTX * X(6) |
| 141 | DS12=X(4) + FACTX * X(6) |
| 142 | S2 = 0.5 * (PAR(3) + PAR(4)) + FACTY * X(3) |
| 143 | DS21=X(5) - FACTY * X(6) |
| 144 | DS22=X(5) + FACTY * X(6) |
| 145 | |
| 146 | C |
| 147 | C FIRST DO THE Z COORDINATE. |
| 148 | C |
| 149 | 60 SMAX=9.0E+10 |
| 150 | SMIN=0.0 |
| 151 | IF(X(6).EQ.0.0.AND.S3.LT.ABS(X(3))) GO TO 999 |
| 152 | IF(X(6).EQ.0.0) GO TO 70 |
| 153 | SMIN=(S3-X(3))/X(6) |
| 154 | SMAX=(-S3-X(3))/X(6) |
| 155 | IF(SMAX.GT.SMIN) GO TO 70 |
| 156 | SN=SMAX |
| 157 | SMAX=SMIN |
| 158 | SMIN=SN |
| 159 | C |
| 160 | 70 IF(SMIN.LT.0.0) SMIN=0.0 |
| 161 | IF(SMAX.LT.SMIN) GO TO 999 |
| 162 | C |
| 163 | C NOW DO X COORDINATE. |
| 164 | C |
| 165 | SS1=S1-X(1) |
| 166 | SS2=-S1-X(1) |
| 167 | SN1=-1.0 |
| 168 | SN2=SMAX |
| 169 | * |
| 170 | IF(SS1.LT.0.0) SN1=SMAX |
| 171 | IF(SS2.GT.0.0) SN2=-1.0 |
| 172 | * |
| 173 | IF(DS11.NE.0.0) SN1=SS1/DS11 |
| 174 | IF(DS12.NE.0.0) SN2=SS2/DS12 |
| 175 | IF(DS12*DS11.EQ.0.0) GO TO 90 |
| 176 | IF(DS12.LT.0.0.AND.DS11.LT.0.0) GO TO 110 |
| 177 | ST=SN2 |
| 178 | SN2=SN1 |
| 179 | SN1=ST |
| 180 | IF(DS12.GT.0.0.AND.DS11.GT.0.0) GO TO 110 |
| 181 | IF(DS12.LT.0.0) GO TO 80 |
| 182 | IF(SN2.GT.SN1) SN1=SN2 |
| 183 | SN2=SMAX |
| 184 | GO TO 110 |
| 185 | C |
| 186 | 80 CONTINUE |
| 187 | C |
| 188 | IF(SN2.GT.SN1) SN2=SN1 |
| 189 | SN1=0.0 |
| 190 | GO TO 110 |
| 191 | C |
| 192 | 90 CONTINUE |
| 193 | C |
| 194 | IF(DS12.EQ.0.0.AND.SS2.GT.0.0) GO TO 999 |
| 195 | IF(DS12.EQ.0.0.AND.DS11.LT.0.0) GO TO 110 |
| 196 | IF(DS11.EQ.0.0.AND.SS1.LT.0.0) GO TO 999 |
| 197 | IF(DS11.EQ.0.0.AND.DS12.LE.0.0) GO TO 110 |
| 198 | IF(DS11.EQ.0.0) GO TO 100 |
| 199 | SN2=SN1 |
| 200 | SN1=0.0 |
| 201 | GO TO 110 |
| 202 | C |
| 203 | 100 CONTINUE |
| 204 | SN1=SN2 |
| 205 | SN2=SMAX |
| 206 | C |
| 207 | 110 CONTINUE |
| 208 | C |
| 209 | IF(SN1.GT.SMIN) SMIN=SN1 |
| 210 | IF(SN2.LT.SMAX) SMAX=SN2 |
| 211 | IF(SMAX.LE.SMIN) GO TO 999 |
| 212 | C |
| 213 | C NOW DO Y COORDINATE. |
| 214 | C |
| 215 | SS1=S2-X(2) |
| 216 | SS2=-S2-X(2) |
| 217 | SN1=-1.0 |
| 218 | SN2=SMAX |
| 219 | * |
| 220 | IF(SS1.LT.0.0) SN1=SMAX |
| 221 | IF(SS2.GT.0.0) SN2=-1.0 |
| 222 | * |
| 223 | IF(DS21.NE.0.0) SN1=SS1/DS21 |
| 224 | IF(DS22.NE.0.0) SN2=SS2/DS22 |
| 225 | IF(DS22*DS21.EQ.0.0) GO TO 130 |
| 226 | IF(DS22.LT.0.0.AND.DS21.LT.0.0) GO TO 150 |
| 227 | ST=SN2 |
| 228 | SN2=SN1 |
| 229 | SN1=ST |
| 230 | IF(DS22.GT.0.0.AND.DS21.GT.0.0) GO TO 150 |
| 231 | IF(DS22.LT.0.0) GO TO 120 |
| 232 | IF(SN2.GT.SN1) SN1=SN2 |
| 233 | SN2=SMAX |
| 234 | GO TO 150 |
| 235 | C |
| 236 | 120 CONTINUE |
| 237 | C |
| 238 | IF(SN2.GT.SN1) SN2=SN1 |
| 239 | SN1=0.0 |
| 240 | GO TO 150 |
| 241 | C |
| 242 | 130 CONTINUE |
| 243 | C |
| 244 | IF(DS22.EQ.0.0.AND.SS2.GT.0.0) GO TO 999 |
| 245 | IF(DS22.EQ.0.0.AND.DS21.LT.0.0) GO TO 150 |
| 246 | IF(DS21.EQ.0.0.AND.SS1.LT.0.0) GO TO 999 |
| 247 | IF(DS21.EQ.0.0.AND.DS22.LE.0.0) GO TO 150 |
| 248 | IF(DS21.EQ.0.0) GO TO 140 |
| 249 | SN2=SN1 |
| 250 | SN1=0.0 |
| 251 | GO TO 150 |
| 252 | C |
| 253 | 140 CONTINUE |
| 254 | SN1=SN2 |
| 255 | SN2=SMAX |
| 256 | C |
| 257 | 150 CONTINUE |
| 258 | C |
| 259 | IF(SN1.GT.SMIN) SMIN=SN1 |
| 260 | IF(SN2.LT.SMAX) SMAX=SN2 |
| 261 | C |
| 262 | IF(SMAX.LE.SMIN) GO TO 999 |
| 263 | IF(SMIN.LE.0.)GO TO 999 |
| 264 | SNXT = SMIN |
| 265 | |
| 266 | 999 CONTINUE |
| 267 | END |
git://git.uio.no / u / mrichter / AliRoot.git / blame