Geant4 Cross Reference

Cross-Referencing   Geant4
Geant4/visualization/OpenInventor/src/SoTubs.cc

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  1 //
  2 // ********************************************************************
  3 // * License and Disclaimer                                           *
  4 // *                                                                  *
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  6 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
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  9 // * include a list of copyright holders.                             *
 10 // *                                                                  *
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 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 *
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 18 // * This  code  implementation is the result of  the  scientific and *
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 23 // * acceptance of all terms of the Geant4 Software license.          *
 24 // ********************************************************************
 25 //
 26 //
 27 //
 28 //
 29 /*-----------------------------HEPVis---------------------------------------*/
 30 /*                                                                          */
 31 /* Node:             SoTubs                                                 */
 32 /* Description:      Represents the G4Tubs Geant Geometry entity            */
 33 /* Author:           Joe Boudreau Nov 11 1996                               */
 34 /*                                                                          */
 35 /*--------------------------------------------------------------------------*/
 36 
 37 // this :
 38 #include "HEPVis/nodes/SoTubs.h"
 39 
 40 #include <assert.h>
 41 #include <cmath>
 42 
 43 #include <Inventor/SbBox.h>
 44 #include <Inventor/actions/SoGLRenderAction.h>
 45 #include <Inventor/fields/SoSFFloat.h>
 46 #include <Inventor/misc/SoChildList.h>
 47 #include <Inventor/nodes/SoSeparator.h>
 48 #include <Inventor/nodes/SoIndexedFaceSet.h>
 49 #include <Inventor/nodes/SoNormal.h>
 50 #include <Inventor/nodes/SoCoordinate3.h>
 51 #include <Inventor/nodes/SoNormalBinding.h>
 52 #include <Inventor/SoPrimitiveVertex.h>
 53 #include <Inventor/elements/SoTextureCoordinateElement.h>
 54 
 55 #include "HEPVis/SbMath.h"
 56 
 57 // This statement is required
 58 SO_NODE_SOURCE(SoTubs)
 59 
 60 // Constructor
 61 SoTubs::SoTubs() {
 62 
 63 
 64   // This statement is required
 65   SO_NODE_CONSTRUCTOR(SoTubs);
 66 
 67   // Data fields are initialized like this:
 68   SO_NODE_ADD_FIELD(pRMin,               (0));
 69   SO_NODE_ADD_FIELD(pRMax,               (1));
 70   SO_NODE_ADD_FIELD(pDz,                 (10));
 71   SO_NODE_ADD_FIELD(pSPhi,               (0));
 72   SO_NODE_ADD_FIELD(pDPhi,               ((float)(2*M_PI)));
 73   SO_NODE_ADD_FIELD(alternateRep,        (NULL));
 74   children = new SoChildList(this);
 75 }
 76 
 77 // Destructor
 78 SoTubs::~SoTubs() {
 79   delete children;
 80 }
 81 
 82 
 83 // initClass
 84 void SoTubs::initClass(){
 85   // This statement is required.
 86   static bool first = true;
 87   if (first) {
 88     first = false;
 89     SO_NODE_INIT_CLASS(SoTubs,SoShape,"Shape");
 90   }
 91 }
 92 
 93 // generatePrimitives
 94 void SoTubs::generatePrimitives(SoAction *action) {
 95   // This variable is used to store each vertex
 96   SoPrimitiveVertex pv;
 97 
 98   // Access the stat from the action
 99   SoState *state = action->getState();
100 
101   // See if we have to use a texture coordinate function,
102   // rather than generating explicit texture coordinates.
103   SbBool useTexFunction=
104     (SoTextureCoordinateElement::getType(state) == 
105      SoTextureCoordinateElement::FUNCTION);
106 
107   // If we need to generate texture coordinates with a function,
108   // we'll need an SoGLTextureCoordinateElement.  Otherwise, we'll
109   // set up the coordinates directly.
110   const SoTextureCoordinateElement* tce = NULL;
111   SbVec4f texCoord;
112   if (useTexFunction) {
113     tce = SoTextureCoordinateElement::getInstance(state);
114   }
115   else {
116     texCoord[2] = 0.0;
117     texCoord[3] = 1.0;
118   }
119   SbVec3f point, normal;
120 
121 
122   ///////////////////////////////////////////////////////
123   //-----------------------------------------------------
124 #define GEN_VERTEX(pv,x,y,z,s,t,nx,ny,nz)               \
125   point.setValue((float)(x),(float)(y),(float)(z));     \
126   normal.setValue((float)(nx),(float)(ny),(float)(nz)); \
127   if (useTexFunction) {                                 \
128     texCoord=tce->get(point,normal);                    \
129   } else {                                              \
130     texCoord[0]=(float)(s);                             \
131     texCoord[1]=(float)(t);                             \
132   }                                                     \
133   pv.setPoint(point);                                   \
134   pv.setNormal(normal);                                 \
135   pv.setTextureCoords(texCoord);                        \
136   shapeVertex(&pv);
137   //-----------------------------------------------------
138   ///////////////////////////////////////////////////////
139 
140   int NPHI = (int)(2+22*std::fabs(pDPhi.getValue()/(2.0*M_PI)));
141   double deltaPhi = pDPhi.getValue()/NPHI, phi0 = pSPhi.getValue(),phi1=phi0+pDPhi.getValue();
142   double rMax=pRMax.getValue(),rMin=pRMin.getValue();
143   double zMax=pDz.getValue(),zMin=-zMax;
144   double cosPhi0=std::cos(phi0), sinPhi0=std::sin(phi0);
145   double cosPhi1=std::cos(phi1), sinPhi1=std::sin(phi1);
146   double cosDeltaPhi=std::cos(deltaPhi),sinDeltaPhi=std::sin(deltaPhi);
147   //
148   // The outer surface!
149   //
150   int i;
151   double sinPhi,cosPhi;
152   beginShape(action,TRIANGLE_STRIP);
153   sinPhi=sinPhi0;
154   cosPhi=cosPhi0;
155   for (i = 0; i<=NPHI; i++) {
156     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMax,0.0,0.0,cosPhi,sinPhi,0);   
157     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMin,1.0,1.0,cosPhi,sinPhi,0);   
158     inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
159   }
160   endShape();
161   //
162   // The inner surface!
163   //
164   if(rMin!=0.F) {
165     beginShape(action,TRIANGLE_STRIP);
166     sinPhi=sinPhi0;
167     cosPhi=cosPhi0;
168     for (i = 0; i<=NPHI; i++) {
169       GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMax,0.0,0.0,-cosPhi,-sinPhi,0);   
170       GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMin,1.0,1.0,-cosPhi,-sinPhi,0);   
171       inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
172     } 
173     endShape();
174   }
175   if (std::fabs(deltaPhi)<2.0*M_PI) { 
176     //
177     // The end 
178     //
179     beginShape(action,TRIANGLE_STRIP);
180     sinPhi=sinPhi0;
181     cosPhi=cosPhi0;
182     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMax,0.0,0.0,sinPhi,-cosPhi,0);   
183     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMin,1.0,1.0,sinPhi,-cosPhi,0);   
184     GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMax,1.0,0.0,sinPhi,-cosPhi,0);   
185     GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMin,0.0,1.0,sinPhi,-cosPhi,0);   
186     endShape();
187     //
188     // The other end 
189     //
190     beginShape(action,TRIANGLE_STRIP);
191     sinPhi=sinPhi1;
192     cosPhi=cosPhi1;
193     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi, zMax,0.0,0.0,-sinPhi,+cosPhi,0);   
194     GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi, zMin,1.0,1.0,-sinPhi,+cosPhi,0);   
195     GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi, zMax,1.0,0.0,-sinPhi,+cosPhi,0);   
196     GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi, zMin,0.0,1.0,-sinPhi,+cosPhi,0);   
197     endShape();
198   }
199   //
200   // The outer surface at z=+PDZ
201   //
202   if(rMin==0.F) {
203     beginShape(action,TRIANGLE_FAN);
204     sinPhi=sinPhi0;
205     cosPhi=cosPhi0;
206     GEN_VERTEX(pv,0,0,zMax,0.0,0.0,0,0,1);   
207     for (i = 0; i<=NPHI; i++) {
208       GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMax,1.0,1.0,0,0,1);   
209       inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
210     }
211     endShape();
212     //
213     // The outer surface at z=-PDZ
214     //
215     beginShape(action,TRIANGLE_FAN);
216     sinPhi=sinPhi0;
217     cosPhi=cosPhi0;
218     GEN_VERTEX(pv,0,0,zMin,0.0,0.0,0,0,-1);   
219     for (i = 0; i<=NPHI; i++) {
220       GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMin,1.0,1.0,0,0,-1);   
221       inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
222     }
223     endShape();
224   } else {
225     beginShape(action,TRIANGLE_STRIP);
226     sinPhi=sinPhi0;
227     cosPhi=cosPhi0;
228     for (i = 0; i<=NPHI; i++) {
229       GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMax,0.0,0.0,0,0,1);   
230       GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMax,1.0,1.0,0,0,1);   
231       inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
232     }
233     endShape();
234     //
235     // The outer surface at z=-PDZ
236     //
237     beginShape(action,TRIANGLE_STRIP);
238     sinPhi=sinPhi0;
239     cosPhi=cosPhi0;
240     for (i = 0; i<=NPHI; i++) {
241       GEN_VERTEX(pv,rMin*cosPhi,rMin*sinPhi,zMin,0.0,0.0,0,0,-1);   
242       GEN_VERTEX(pv,rMax*cosPhi,rMax*sinPhi,zMin,1.0,1.0,0,0,-1);   
243       inc(sinPhi, cosPhi, sinDeltaPhi, cosDeltaPhi);    
244     }
245     endShape();
246   }
247 }
248 
249 // getChildren
250 SoChildList *SoTubs::getChildren() const {
251   return children;
252 }
253 
254 
255 // computeBBox
256 void SoTubs::computeBBox(SoAction *, SbBox3f &box, SbVec3f &center ){
257   SbVec3f vmin(-pRMax.getValue(),-pRMax.getValue(),-pDz.getValue()), 
258           vmax( pRMax.getValue(), pRMax.getValue(), pDz.getValue());
259   center.setValue(0,0,0);
260   box.setBounds(vmin,vmax);
261 }
262 
263 
264 // updateChildren
265 void SoTubs::updateChildren() {
266 
267   // Redraw the G4Tubs....
268 
269   assert(children->getLength()==1);
270   SoSeparator       *sep                = (SoSeparator *)  ( *children)[0];
271   SoCoordinate3     *theCoordinates     = (SoCoordinate3 *)      ( sep->getChild(0));
272   SoNormal          *theNormals         = (SoNormal *)           ( sep->getChild(1)); 
273   SoNormalBinding   *theNormalBinding   = (SoNormalBinding *)    ( sep->getChild(2));
274   SoIndexedFaceSet  *theFaceSet         = (SoIndexedFaceSet *)   ( sep->getChild(3));
275   
276   
277   const int NPHI=24, NPOINTS=2*(2*NPHI+2), NFACES=4*NPHI+2, NINDICES = NFACES*5;
278   float points[NPOINTS][3],normals[NFACES][3];
279 #ifdef INVENTOR2_0
280   static long     indices[NINDICES];
281 #else
282   static int32_t  indices[NINDICES];
283 #endif
284     
285   static int init=0;
286   double phi, pp, DeltaPhi;
287     
288   // Indices need to be generated once! This is here to keep it close to the point
289   // generation, since otherwise it will be confusing.
290     
291   int i;
292   if (!init) {
293     init = 1;
294     // Outer face
295     for (i = 0; i< NPHI; i++) {
296       // 0 1 3 2;
297       indices[5*i+0] =  2*i+0;
298       indices[5*i+1] =  2*i+1;
299       indices[5*i+2] =  2*i+3;
300       indices[5*i+3] =  2*i+2;
301       indices[5*i+4] = SO_END_FACE_INDEX;
302     }
303     // the inner face
304     for (i=0;i<NPHI;i++) {
305       indices[5*1*NPHI + 5*i+0] = 2*NPHI+2 + 2*i+0;  
306       indices[5*1*NPHI + 5*i+1] = 2*NPHI+2 + 2*i+1;
307       indices[5*1*NPHI + 5*i+2] = 2*NPHI+2 + 2*i+3;
308       indices[5*1*NPHI + 5*i+3] = 2*NPHI+2 + 2*i+2;
309       indices[5*1*NPHI + 5*i+4] = SO_END_FACE_INDEX;
310     }
311     // the top side
312     for (i=0;i<NPHI;i++) {
313       indices[5*2*NPHI + 5*i+0] = 2*i+0;
314       indices[5*2*NPHI + 5*i+1] = 2*i+2;
315       indices[5*2*NPHI + 5*i+2] = NPOINTS - (2*i+4);
316       indices[5*2*NPHI + 5*i+3] = NPOINTS - (2*i+2);
317       indices[5*2*NPHI + 5*i+4] = SO_END_FACE_INDEX;
318     }
319     // the bottom side
320     for (i=0;i<NPHI;i++) {
321       indices[5*3*NPHI + 5*i+0] = 2*i+1;
322       indices[5*3*NPHI + 5*i+1] = NPOINTS - (2*i+1);
323       indices[5*3*NPHI + 5*i+2] = NPOINTS - (2*i+3);
324       indices[5*3*NPHI + 5*i+3] = 2*i+3;
325       indices[5*3*NPHI + 5*i+4] = SO_END_FACE_INDEX;
326     }
327     // the odd side
328     indices[5*4*NPHI +0] = 2*NPHI;
329     indices[5*4*NPHI +1] = 2*NPHI+1;
330     indices[5*4*NPHI +2] = 2*NPHI+3;
331     indices[5*4*NPHI +3] = 2*NPHI+2;
332     indices[5*4*NPHI +4] = SO_END_FACE_INDEX;
333     // aother odd side
334     indices[5*4*NPHI +5 +0] = 0;
335     indices[5*4*NPHI +5 +1] = NPOINTS-2;
336     indices[5*4*NPHI +5 +2] = NPOINTS-1;
337     indices[5*4*NPHI +5 +3] = 1;
338     indices[5*4*NPHI +5 +4] = SO_END_FACE_INDEX;
339   }
340   // Points need to be generated each time:
341   if (pDPhi.getValue()<2*M_PI) {
342     // the odd side
343     indices[5*4*NPHI +0] = 2*NPHI;
344     indices[5*4*NPHI +1] = 2*NPHI+1;
345     indices[5*4*NPHI +2] = 2*NPHI+3;
346     indices[5*4*NPHI +3] = 2*NPHI+2;
347     indices[5*4*NPHI +4] = SO_END_FACE_INDEX;
348     // aother odd side
349     indices[5*4*NPHI +5 +0] = 0;
350     indices[5*4*NPHI +5 +1] = NPOINTS-2;
351     indices[5*4*NPHI +5 +2] = NPOINTS-1;
352     indices[5*4*NPHI +5 +3] = 1;
353     indices[5*4*NPHI +5 +4] = SO_END_FACE_INDEX;
354   } 
355   else {
356     // the odd side
357     indices[5*4*NPHI +0] = SO_END_FACE_INDEX;
358     indices[5*4*NPHI +1] = SO_END_FACE_INDEX;
359     indices[5*4*NPHI +2] = SO_END_FACE_INDEX;
360     indices[5*4*NPHI +3] = SO_END_FACE_INDEX;
361     indices[5*4*NPHI +4] = SO_END_FACE_INDEX;
362     // aother odd side
363     indices[5*4*NPHI +5 +0] = SO_END_FACE_INDEX;
364     indices[5*4*NPHI +5 +1] = SO_END_FACE_INDEX;
365     indices[5*4*NPHI +5 +2] = SO_END_FACE_INDEX;
366     indices[5*4*NPHI +5 +3] = SO_END_FACE_INDEX;
367     indices[5*4*NPHI +5 +4] = SO_END_FACE_INDEX;
368   }
369   // The outer surface
370   DeltaPhi = pDPhi.getValue()/NPHI, phi = pSPhi.getValue();
371   for (i = 0; i<=NPHI; i++) {
372     points[2*i+0][0] = pRMax.getValue()*FCOS(phi); 
373     points[2*i+0][1]= pRMax.getValue()*FSIN(phi); 
374     points[2*i+0][2] = +pDz.getValue();
375 
376     points[2*i+1][0] = pRMax.getValue()*FCOS(phi); 
377     points[2*i+1][1]= pRMax.getValue()*FSIN(phi); 
378     points[2*i+1][2] = -pDz.getValue();
379 
380     pp = phi+DeltaPhi/2.0;
381     if (i!=NPHI) {
382       normals[i][0] = FCOS(pp); 
383       normals[i][1] = FSIN(pp); 
384       normals[i][2] = 0;
385     }
386     phi+=DeltaPhi;
387   }
388   // The inner surface
389   phi = pSPhi.getValue() + pDPhi.getValue();
390   for (i = 0; i<=NPHI; i++) {
391     points[2*NPHI+2+2*i+0][0] = pRMin.getValue()*FCOS(phi); 
392     points[2*NPHI+2+2*i+0][1] = pRMin.getValue()*FSIN(phi); 
393     points[2*NPHI+2+2*i+0][2] = +pDz.getValue();
394     points[2*NPHI+2+2*i+1][0] = pRMin.getValue()*FCOS(phi); 
395     points[2*NPHI+2+2*i+1][1] = pRMin.getValue()*FSIN(phi); 
396     points[2*NPHI+2+2*i+1][2] = -pDz.getValue();
397     pp = phi-DeltaPhi/2.0;
398     if (i!=NPHI) {
399       normals[NPHI+i][0] = -FCOS(pp); 
400       normals[NPHI+i][1] = -FSIN(pp); 
401       normals[NPHI+i][2] = 0;
402     }
403     phi-=DeltaPhi;
404   }
405   // The top side
406   for (i=0;i<NPHI;i++) {
407     normals[2*NPHI+i][0]=normals[2*NPHI+i][1]=0; 
408     normals[2*NPHI+i][2]=  1.0;
409   } 
410   // The bottom side
411   for (i=0;i<NPHI;i++) {
412     normals[3*NPHI+i][0]=normals[3*NPHI+i][1]=0; 
413     normals[3*NPHI+i][2]= -1.0;
414   } 
415   // The odd side
416   phi = pSPhi.getValue(); 
417   normals[4*NPHI+0][0]=  FSIN(phi); 
418   normals[4*NPHI+0][1]= -FCOS(phi); 
419   normals[4*NPHI+0][2]=0;
420     
421     // Another odd side
422   phi = pSPhi.getValue()+pDPhi.getValue(); 
423   normals[4*NPHI+1][0]= -FSIN(phi); 
424   normals[4*NPHI+1][1]= +FCOS(phi); 
425   normals[4*NPHI+1][2]=0;
426     
427   for (int np=0;np<NPOINTS; np++) theCoordinates->point.set1Value(np,points[np][0],points[np][1],points[np][2]);
428   for (int ni=0;ni<NINDICES;ni++) theFaceSet->coordIndex.set1Value(ni,indices[ni]);
429   for (int nf=0;nf<NFACES;nf++) theNormals->vector.set1Value(nf,normals[nf][0],normals[nf][1],normals[nf][2]);
430   theNormalBinding->value=SoNormalBinding::PER_FACE;
431 }
432 
433 // generateChildren
434 void SoTubs::generateChildren() {
435 
436   // This routines creates one SoSeparator, one SoCoordinate3, and
437   // one SoLineSet, and puts it in the child list.  This is done only
438   // once, whereas redrawing the position of the coordinates occurs each
439   // time an update is necessary, in the updateChildren routine. 
440 
441   assert(children->getLength() ==0);
442   SoSeparator      *sep              = new SoSeparator(); 
443   SoCoordinate3    *theCoordinates   = new SoCoordinate3();
444   SoNormal         *theNormals       = new SoNormal(); 
445   SoNormalBinding  *theNormalBinding = new SoNormalBinding();
446   SoIndexedFaceSet *theFaceSet       = new SoIndexedFaceSet();
447   // 
448   // This line costs some in render quality! but gives speed.
449   // 
450   sep->addChild(theCoordinates);
451   sep->addChild(theNormals);
452   sep->addChild(theNormalBinding);
453   sep->addChild(theFaceSet);
454   children->append(sep);
455 }
456 
457 // generateAlternateRep
458 void SoTubs::generateAlternateRep() {
459 
460   // This routine sets the alternate representation to the child
461   // list of this mode.  
462 
463   if (children->getLength() == 0) generateChildren();
464   updateChildren();
465   alternateRep.setValue((SoSeparator *)  ( *children)[0]);
466 }
467 
468 // clearAlternateRep
469 void SoTubs::clearAlternateRep() {
470   alternateRep.setValue(NULL);
471 }
472