1 | // |
---|
2 | // ******************************************************************** |
---|
3 | // * License and Disclaimer * |
---|
4 | // * * |
---|
5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
7 | // * conditions of the Geant4 Software License, included in the file * |
---|
8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
9 | // * include a list of copyright holders. * |
---|
10 | // * * |
---|
11 | // * Neither the authors of this software system, nor their employing * |
---|
12 | // * institutes,nor the agencies providing financial support for this * |
---|
13 | // * work make any representation or warranty, express or implied, * |
---|
14 | // * regarding this software system or assume any liability for its * |
---|
15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
16 | // * for the full disclaimer and the limitation of liability. * |
---|
17 | // * * |
---|
18 | // * This code implementation is the result of the scientific and * |
---|
19 | // * technical work of the GEANT4 collaboration. * |
---|
20 | // * By using, copying, modifying or distributing the software (or * |
---|
21 | // * any work based on the software) you agree to acknowledge its * |
---|
22 | // * use in resulting scientific publications, and indicate your * |
---|
23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
24 | // ******************************************************************** |
---|
25 | // |
---|
26 | // |
---|
27 | // $Id: G4FCylindricalSurface.cc,v 1.16 2006/06/29 18:42:14 gunter Exp $ |
---|
28 | // GEANT4 tag $Name: geant4-09-03 $ |
---|
29 | // |
---|
30 | // ---------------------------------------------------------------------- |
---|
31 | // GEANT 4 class source file |
---|
32 | // |
---|
33 | // G4FCylindricalSurface.cc |
---|
34 | // |
---|
35 | // ---------------------------------------------------------------------- |
---|
36 | |
---|
37 | #include "G4FCylindricalSurface.hh" |
---|
38 | #include "G4Sort.hh" |
---|
39 | |
---|
40 | |
---|
41 | G4FCylindricalSurface::G4FCylindricalSurface() |
---|
42 | : length(1.) |
---|
43 | { |
---|
44 | } |
---|
45 | |
---|
46 | |
---|
47 | G4FCylindricalSurface::~G4FCylindricalSurface() |
---|
48 | { |
---|
49 | } |
---|
50 | |
---|
51 | |
---|
52 | G4FCylindricalSurface::G4FCylindricalSurface( const G4Point3D& o, |
---|
53 | const G4Vector3D& a, |
---|
54 | G4double r, |
---|
55 | G4double l |
---|
56 | ) |
---|
57 | { |
---|
58 | // make a G4FCylindricalSurface with origin o, axis a, |
---|
59 | // radius r, and length l |
---|
60 | G4Vector3D dir(1,1,1); |
---|
61 | Position.Init(dir, a, o); |
---|
62 | |
---|
63 | origin = o; |
---|
64 | radius = r; |
---|
65 | |
---|
66 | // Require length to be positive or zero |
---|
67 | if ( l >= 0.0 ) |
---|
68 | length = l; |
---|
69 | else |
---|
70 | { |
---|
71 | G4cerr << "Error in G4FCylindricalSurface::G4FCylindricalSurface" |
---|
72 | << "--asked for negative length\n" |
---|
73 | << "\tDefault length of 0.0 is used.\n"; |
---|
74 | |
---|
75 | length = 0.0; |
---|
76 | } |
---|
77 | |
---|
78 | // Require radius to be non-negative (i.e., allow zero) |
---|
79 | if ( r >= 0.0 ) |
---|
80 | radius = r; |
---|
81 | else |
---|
82 | { |
---|
83 | G4cerr << "Error in G4FCylindricalSurface::G4FCylindricalSurface" |
---|
84 | << "--asked for negative radius\n" |
---|
85 | << "\tDefault value of 0.0 is used.\n"; |
---|
86 | |
---|
87 | radius = 0.0; |
---|
88 | } |
---|
89 | } |
---|
90 | |
---|
91 | |
---|
92 | const char* G4FCylindricalSurface::NameOf() const |
---|
93 | { |
---|
94 | return "G4FCylindricalSurface"; |
---|
95 | } |
---|
96 | |
---|
97 | |
---|
98 | void G4FCylindricalSurface::PrintOn( std::ostream& os ) const |
---|
99 | { |
---|
100 | os << "G4FCylindricalSurface with origin: " << origin << "\t" |
---|
101 | << "and axis: " << Position.GetAxis() << "\n" |
---|
102 | << "\t radius: " << radius << "\t and length: " |
---|
103 | << length << "\n"; |
---|
104 | } |
---|
105 | |
---|
106 | |
---|
107 | G4double G4FCylindricalSurface::Area() const |
---|
108 | { |
---|
109 | return ( 2.0 * pi * radius * length ); |
---|
110 | } |
---|
111 | |
---|
112 | |
---|
113 | // Added 18.7-95 |
---|
114 | // Modified by L. Broglia (01/12/98) |
---|
115 | void G4FCylindricalSurface::CalcBBox() |
---|
116 | { |
---|
117 | // Finds the bounds of the surface iow |
---|
118 | // calculates the bounds for a bounding box |
---|
119 | // to the surface. The bounding box is used |
---|
120 | // for a preliminary check of intersection. |
---|
121 | G4Point3D Max = G4Point3D(-PINFINITY); |
---|
122 | G4Point3D Min = G4Point3D( PINFINITY); |
---|
123 | |
---|
124 | G4Point3D Tmp; |
---|
125 | G4Point3D Origin = Position.GetLocation(); |
---|
126 | G4Point3D EndOrigin = G4Point3D( Origin + (length*Position.GetAxis()) ); |
---|
127 | G4Point3D Radius(radius, radius, 0); |
---|
128 | |
---|
129 | // Default BBox |
---|
130 | G4Point3D Tolerance(kCarTolerance, kCarTolerance, kCarTolerance); |
---|
131 | G4Point3D BoxMin(Origin-Tolerance); |
---|
132 | G4Point3D BoxMax(Origin+Tolerance); |
---|
133 | |
---|
134 | bbox = new G4BoundingBox3D(); |
---|
135 | bbox->Init(BoxMin, BoxMax); |
---|
136 | |
---|
137 | |
---|
138 | Tmp = (Origin - Radius); |
---|
139 | bbox->Extend(Tmp); |
---|
140 | |
---|
141 | Tmp = Origin + Radius; |
---|
142 | bbox->Extend(Tmp); |
---|
143 | |
---|
144 | Tmp = EndOrigin - Radius; |
---|
145 | bbox->Extend(Tmp); |
---|
146 | |
---|
147 | Tmp = EndOrigin + Radius; |
---|
148 | bbox->Extend(Tmp); |
---|
149 | } |
---|
150 | |
---|
151 | |
---|
152 | G4int G4FCylindricalSurface::Intersect( const G4Ray& ry ) |
---|
153 | { |
---|
154 | // This function count the number of intersections of a |
---|
155 | // bounded cylindrical surface by a ray. |
---|
156 | // At first, calculates the intersections with the infinite |
---|
157 | // cylindrical surfsace. After, count the intersections within the |
---|
158 | // finite cylindrical surface boundaries, and set "distance" to the |
---|
159 | // closest distance from the start point to the nearest intersection |
---|
160 | // If the point is on the surface it returns or the intersection with |
---|
161 | // the opposite surface or kInfinity |
---|
162 | |
---|
163 | // If no intersection is founded, set distance = kInfinity and |
---|
164 | // return 0 |
---|
165 | |
---|
166 | distance = kInfinity; |
---|
167 | closest_hit = PINFINITY; |
---|
168 | |
---|
169 | // origin and direction of the ray |
---|
170 | G4Point3D x = ry.GetStart(); |
---|
171 | G4Vector3D dhat = ry.GetDir(); |
---|
172 | |
---|
173 | // cylinder axis |
---|
174 | G4Vector3D ahat = Position.GetAxis(); |
---|
175 | |
---|
176 | // array of solutions in distance along the ray |
---|
177 | G4double s[2]; |
---|
178 | s[0]=-1.0; |
---|
179 | s[1]=-1.0; |
---|
180 | |
---|
181 | // calculate the two intersections (quadratic equation) |
---|
182 | G4Vector3D gamma = G4Vector3D( x - Position.GetLocation() ); |
---|
183 | |
---|
184 | G4double ga = gamma * ahat; |
---|
185 | G4double da = dhat * ahat; |
---|
186 | |
---|
187 | G4double A = da * da - dhat * dhat; |
---|
188 | G4double B = 2 * ( -gamma * dhat + ga * da ); |
---|
189 | G4double C = -gamma * gamma + ga * ga + radius * radius ; |
---|
190 | |
---|
191 | G4double radical = B * B - 4.0 * A * C; |
---|
192 | |
---|
193 | if ( radical < 0.0 ) |
---|
194 | // no intersection |
---|
195 | return 0; |
---|
196 | else |
---|
197 | { |
---|
198 | G4double root = std::sqrt( radical ); |
---|
199 | s[0] = ( - B + root ) / ( 2. * A ); |
---|
200 | s[1] = ( - B - root ) / ( 2. * A ); |
---|
201 | } |
---|
202 | |
---|
203 | // validity of the solutions |
---|
204 | // the hit point must be into the bounding box of the cylindrical surface |
---|
205 | G4Point3D p0 = G4Point3D( x + s[0]*dhat ); |
---|
206 | G4Point3D p1 = G4Point3D( x + s[1]*dhat ); |
---|
207 | |
---|
208 | if( !GetBBox()->Inside(p0) ) |
---|
209 | s[0] = kInfinity; |
---|
210 | |
---|
211 | if( !GetBBox()->Inside(p1) ) |
---|
212 | s[1] = kInfinity; |
---|
213 | |
---|
214 | // now loop over each positive solution, keeping the first one (smallest |
---|
215 | // distance along the Ray) which is within the boundary of the sub-shape |
---|
216 | G4int nbinter = 0; |
---|
217 | distance = kInfinity; |
---|
218 | |
---|
219 | for ( G4int i = 0; i < 2; i++ ) |
---|
220 | { |
---|
221 | if(s[i] < kInfinity) { |
---|
222 | if ( s[i] >= kCarTolerance*0.5 ) { |
---|
223 | nbinter ++; |
---|
224 | // real intersection |
---|
225 | // set the distance if it is the smallest |
---|
226 | if( distance > s[i]*s[i]) { |
---|
227 | distance = s[i]*s[i]; |
---|
228 | } |
---|
229 | } |
---|
230 | } |
---|
231 | } |
---|
232 | |
---|
233 | return nbinter; |
---|
234 | } |
---|
235 | |
---|
236 | |
---|
237 | G4double G4FCylindricalSurface::HowNear( const G4Vector3D& x ) const |
---|
238 | { |
---|
239 | // Shortest distance from the point x to the G4FCylindricalSurface. |
---|
240 | // The distance will be always positive |
---|
241 | |
---|
242 | G4double hownear; |
---|
243 | |
---|
244 | G4Vector3D upcorner = G4Vector3D ( radius, 0 , origin.z()+length); |
---|
245 | G4Vector3D downcorner = G4Vector3D ( radius, 0 , origin.z()); |
---|
246 | G4Vector3D xd; |
---|
247 | |
---|
248 | xd = G4Vector3D ( std::sqrt ( x.x()*x.x() + x.y()*x.y() ) , 0 , x.z() ); |
---|
249 | |
---|
250 | |
---|
251 | G4double Zinter = (xd.z()) ; |
---|
252 | |
---|
253 | if ( ((Zinter >= downcorner.z()) && (Zinter <=upcorner.z())) ) { |
---|
254 | hownear = std::fabs( radius - xd.x() ); |
---|
255 | } else { |
---|
256 | hownear = std::min ( (xd-upcorner).mag() , (xd-downcorner).mag() ); |
---|
257 | } |
---|
258 | |
---|
259 | return hownear; |
---|
260 | } |
---|
261 | |
---|
262 | G4int G4FCylindricalSurface::WithinBoundary( const G4Vector3D& x ) const |
---|
263 | { |
---|
264 | // return 1 if point x is within the boundaries of the G4FCylindricalSurface |
---|
265 | // return 0 otherwise (assume it is on the cylinder) |
---|
266 | if ( std::fabs( ( x - Position.GetLocation()) * Position.GetAxis() ) |
---|
267 | <= 0.5 * length ) |
---|
268 | return 1; |
---|
269 | else |
---|
270 | return 0; |
---|
271 | } |
---|
272 | |
---|
273 | |
---|
274 | G4double G4FCylindricalSurface::Scale() const |
---|
275 | { |
---|
276 | // Returns the radius of a G4FCylindricalSurface unless it is zero, |
---|
277 | // in which case returns the length. |
---|
278 | // Used for Scale-invariant tests of surface thickness. |
---|
279 | if ( radius == 0.0 ) |
---|
280 | return length; |
---|
281 | else |
---|
282 | return radius; |
---|
283 | } |
---|
284 | |
---|
285 | |
---|
286 | G4Vector3D G4FCylindricalSurface::SurfaceNormal( const G4Point3D& p ) const |
---|
287 | { |
---|
288 | // return the Normal unit vector to the G4CylindricalSurface at a point |
---|
289 | // p on (or nearly on) the G4CylindricalSurface |
---|
290 | |
---|
291 | G4Vector3D n = G4Vector3D( ( p - Position.GetLocation() ) - |
---|
292 | ( ( p - Position.GetLocation()) * |
---|
293 | Position.GetAxis() ) * Position.GetAxis() ); |
---|
294 | G4double nmag = n.mag(); |
---|
295 | |
---|
296 | if ( nmag != 0.0 ) |
---|
297 | n = n * (1/nmag); |
---|
298 | |
---|
299 | if( !sameSense ) |
---|
300 | n = -n; |
---|
301 | |
---|
302 | return n; |
---|
303 | } |
---|
304 | |
---|
305 | G4int G4FCylindricalSurface::Inside ( const G4Vector3D& x ) const |
---|
306 | { |
---|
307 | // Return 0 if point x is outside G4CylindricalSurface, 1 if Inside. |
---|
308 | // Outside means that the distance to the G4CylindricalSurface would |
---|
309 | // be negative. |
---|
310 | // Use the HowNear function to calculate this distance. |
---|
311 | if ( HowNear( x ) >= -0.5*kCarTolerance ) |
---|
312 | return 1; |
---|
313 | else |
---|
314 | return 0; |
---|
315 | } |
---|
316 | |
---|
317 | |
---|
318 | void G4FCylindricalSurface::resize( G4double r, G4double l ) |
---|
319 | { |
---|
320 | // Resize a G4FCylindricalSurface to a new radius r and new length l |
---|
321 | // Require radius to be non-negative |
---|
322 | if ( r >= 0.0 ) |
---|
323 | radius = r; |
---|
324 | else |
---|
325 | { |
---|
326 | G4cerr << "Error in G4FCylindricalSurface::resize" |
---|
327 | << "--asked for negative radius\n" |
---|
328 | << "\tOriginal value of " << radius << " is retained.\n"; |
---|
329 | } |
---|
330 | |
---|
331 | // Require length to be positive |
---|
332 | if ( l > 0.0 ) |
---|
333 | length = l; |
---|
334 | else |
---|
335 | { |
---|
336 | G4cerr << "Error in G4FCylindricalSurface::resize" |
---|
337 | << "--asked for negative or zero length\n" |
---|
338 | << "\tOriginal value of " << length << " is retained.\n"; |
---|
339 | } |
---|
340 | } |
---|