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TGLCylinder.cxx
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1 // @(#)root/gl:$Id$
2 // Author: Timur Pocheptsov 03/08/2004
3 // NOTE: This code moved from obsoleted TGLSceneObject.h / .cxx - see these
4 // attic files for previous CVS history
5 
6 /*************************************************************************
7  * Copyright (C) 1995-2006, Rene Brun and Fons Rademakers. *
8  * All rights reserved. *
9  * *
10  * For the licensing terms see $ROOTSYS/LICENSE. *
11  * For the list of contributors see $ROOTSYS/README/CREDITS. *
12  *************************************************************************/
13 
14 #include "TGLCylinder.h"
15 #include "TGLRnrCtx.h"
16 #include "TGLIncludes.h"
17 
18 #include "TBuffer3D.h"
19 #include "TBuffer3DTypes.h"
20 #include "TMath.h"
21 
22 // For debug tracing
23 #include "TClass.h"
24 #include "TError.h"
25 
26 TGLVector3 gLowNormalDefault(0., 0., -1.);
27 TGLVector3 gHighNormalDefault(0., 0., 1.);
28 
29 class TGLMesh
30 {
31 protected:
32  // active LOD (level of detail) - quality
33  UInt_t fLOD;
34 
35  Double_t fRmin1, fRmax1, fRmin2, fRmax2;
36  Double_t fDz;
37 
38  //normals for top and bottom (for cuts)
39  TGLVector3 fNlow;
40  TGLVector3 fNhigh;
41 
42  void GetNormal(const TGLVertex3 &vertex, TGLVector3 &normal)const;
43  Double_t GetZcoord(Double_t x, Double_t y, Double_t z)const;
44  const TGLVertex3 &MakeVertex(Double_t x, Double_t y, Double_t z)const;
45 
46 public:
47  TGLMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t dz,
48  const TGLVector3 &l = gLowNormalDefault, const TGLVector3 &h = gHighNormalDefault);
49  virtual ~TGLMesh() { }
50  virtual void Draw() const = 0;
51 };
52 
53 //segment contains 3 quad strips:
54 //one for inner and outer sides, two for top and bottom
55 class TubeSegMesh : public TGLMesh {
56 private:
57  // Allocate space for highest quality (LOD) meshes
58  TGLVertex3 fMesh[(TGLRnrCtx::kLODHigh + 1) * 8 + 8];
59  TGLVector3 fNorm[(TGLRnrCtx::kLODHigh + 1) * 8 + 8];
60 
61 public:
62  TubeSegMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t dz,
63  Double_t phi1, Double_t phi2, const TGLVector3 &l = gLowNormalDefault,
64  const TGLVector3 &h = gHighNormalDefault);
65 
66  void Draw() const;
67 };
68 
69 //four quad strips:
70 //outer, inner, top, bottom
71 class TubeMesh : public TGLMesh
72 {
73 private:
74  // Allocate space for highest quality (LOD) meshes
75  TGLVertex3 fMesh[(TGLRnrCtx::kLODHigh + 1) * 8];
76  TGLVector3 fNorm[(TGLRnrCtx::kLODHigh + 1) * 8];
77 
78 public:
79  TubeMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t dz,
80  const TGLVector3 &l = gLowNormalDefault, const TGLVector3 &h = gHighNormalDefault);
81 
82  void Draw() const;
83 };
84 
85 //One quad mesh and 2 triangle funs
86 class TCylinderMesh : public TGLMesh {
87 private:
88  // Allocate space for highest quality (LOD) meshes
89  TGLVertex3 fMesh[(TGLRnrCtx::kLODHigh + 1) * 4 + 2];
90  TGLVector3 fNorm[(TGLRnrCtx::kLODHigh + 1) * 4 + 2];
91 
92 public:
93  TCylinderMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t dz,
94  const TGLVector3 &l = gLowNormalDefault, const TGLVector3 &h = gHighNormalDefault);
95 
96  void Draw() const;
97 };
98 
99 //One quad mesh and 2 triangle fans
100 class TCylinderSegMesh : public TGLMesh
101 {
102 private:
103  // Allocate space for highest quality (LOD) meshes
104  TGLVertex3 fMesh[(TGLRnrCtx::kLODHigh + 1) * 4 + 10];
105  TGLVector3 fNorm[(TGLRnrCtx::kLODHigh + 1) * 4 + 10];
106 
107 public:
108  TCylinderSegMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t dz, Double_t phi1, Double_t phi2,
109  const TGLVector3 &l = gLowNormalDefault, const TGLVector3 &h = gHighNormalDefault);
110  void Draw() const;
111 };
112 
113 TGLMesh::TGLMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t dz,
114  const TGLVector3 &l, const TGLVector3 &h) :
115  fLOD(LOD),
116  fRmin1(r1), fRmax1(r2), fRmin2(r3), fRmax2(r4),
117  fDz(dz), fNlow(l), fNhigh(h)
118 {
119  // constructor
120 }
121 
122 ////////////////////////////////////////////////////////////////////////////////
123 /// get normal
124 
125 void TGLMesh::GetNormal(const TGLVertex3 &v, TGLVector3 &n)const
126 {
127  if( fDz < 1.e-10 ) {
128  n[0] = 0.;
129  n[1] = 0.;
130  n[2] = 1.;
131  }
132  Double_t z = (fRmax1 - fRmax2) / (2 * fDz);
133  Double_t mag = TMath::Sqrt(v[0] * v[0] + v[1] * v[1] + z * z);
134  if( mag > 1.e-10 ) {
135  n[0] = v[0] / mag;
136  n[1] = v[1] / mag;
137  n[2] = z / mag;
138  } else {
139  n[0] = v[0];
140  n[1] = v[1];
141  n[2] = z;
142  }
143 }
144 
145 ////////////////////////////////////////////////////////////////////////////////
146 /// get Z coordinate
147 
148 Double_t TGLMesh::GetZcoord(Double_t x, Double_t y, Double_t z)const
149 {
150  Double_t newz = 0;
151  if (z < 0) newz = -fDz - (x * fNlow[0] + y * fNlow[1]) / fNlow[2];
152  else newz = fDz - (x * fNhigh[0] + y * fNhigh[1]) / fNhigh[2];
153 
154  return newz;
155 }
156 
157 ////////////////////////////////////////////////////////////////////////////////
158 /// make vertex
159 
160 const TGLVertex3 &TGLMesh::MakeVertex(Double_t x, Double_t y, Double_t z)const
161 {
162  static TGLVertex3 vert(0., 0., 0.);
163  vert[0] = x;
164  vert[1] = y;
165  vert[2] = GetZcoord(x, y, z);
166 
167  return vert;
168 }
169 
170 ////////////////////////////////////////////////////////////////////////////////
171 
172 TubeSegMesh::TubeSegMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t dz,
173  Double_t phi1, Double_t phi2,
174  const TGLVector3 &l, const TGLVector3 &h)
175  :TGLMesh(LOD, r1, r2, r3, r4, dz, l, h), fMesh(), fNorm()
176 
177 {
178  // constructor
179  const Double_t delta = (phi2 - phi1) / LOD;
180  Double_t currAngle = phi1;
181 
182  Bool_t even = kTRUE;
183  Double_t c = TMath::Cos(currAngle);
184  Double_t s = TMath::Sin(currAngle);
185  const Int_t topShift = (fLOD + 1) * 4 + 8;
186  const Int_t botShift = (fLOD + 1) * 6 + 8;
187  Int_t j = 4 * (fLOD + 1) + 2;
188 
189  //defining all three strips here, first strip is non-closed here
190  for (Int_t i = 0, e = (fLOD + 1) * 2; i < e; ++i) {
191  if (even) {
192  fMesh[i] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
193  fMesh[j] = MakeVertex(fRmin2 * c, fRmin2 * s, fDz);
194  fMesh[i + topShift] = MakeVertex(fRmin2 * c, fRmin2 * s, fDz);
195  fMesh[i + botShift] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
196  GetNormal(fMesh[j], fNorm[j]);
197  fNorm[j].Negate();
198  even = kFALSE;
199  } else {
200  fMesh[i] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
201  fMesh[j + 1] = MakeVertex(fRmin1 * c, fRmin1 * s, -fDz);
202  fMesh[i + topShift] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
203  fMesh[i + botShift] = MakeVertex(fRmin1 * c, fRmin1 * s, - fDz);
204  GetNormal(fMesh[j + 1], fNorm[j + 1]);
205  fNorm[j + 1].Negate();
206  even = kTRUE;
207  currAngle += delta;
208  c = TMath::Cos(currAngle);
209  s = TMath::Sin(currAngle);
210  j -= 2;
211  }
212 
213  GetNormal(fMesh[i], fNorm[i]);
214  fNorm[i + topShift] = fNhigh;
215  fNorm[i + botShift] = fNlow;
216  }
217 
218  //closing first strip
219  Int_t ind = 2 * (fLOD + 1);
220  TGLVector3 norm(0., 0., 0.);
221 
222  fMesh[ind] = fMesh[ind - 2];
223  fMesh[ind + 1] = fMesh[ind - 1];
224  fMesh[ind + 2] = fMesh[ind + 4];
225  fMesh[ind + 3] = fMesh[ind + 5];
226  TMath::Normal2Plane(fMesh[ind].CArr(), fMesh[ind + 1].CArr(), fMesh[ind + 2].CArr(),
227  norm.Arr());
228  fNorm[ind] = norm;
229  fNorm[ind + 1] = norm;
230  fNorm[ind + 2] = norm;
231  fNorm[ind + 3] = norm;
232 
233  ind = topShift - 4;
234  fMesh[ind] = fMesh[ind - 2];
235  fMesh[ind + 1] = fMesh[ind - 1];
236  fMesh[ind + 2] = fMesh[0];
237  fMesh[ind + 3] = fMesh[1];
238  TMath::Normal2Plane(fMesh[ind].CArr(), fMesh[ind + 1].CArr(), fMesh[ind + 2].CArr(),
239  norm.Arr());
240  fNorm[ind] = norm;
241  fNorm[ind + 1] = norm;
242  fNorm[ind + 2] = norm;
243  fNorm[ind + 3] = norm;
244 }
245 
246 ////////////////////////////////////////////////////////////////////////////////
247 ///Tube segment is drawn as three quad strips
248 ///1. enabling vertex arrays
249 
250 void TubeSegMesh::Draw() const
251 {
252  glEnableClientState(GL_VERTEX_ARRAY);
253  glEnableClientState(GL_NORMAL_ARRAY);
254  //2. setting arrays
255  glVertexPointer(3, GL_DOUBLE, sizeof(TGLVertex3), fMesh[0].CArr());
256  glNormalPointer(GL_DOUBLE, sizeof(TGLVector3), fNorm[0].CArr());
257  //3. draw first strip
258  glDrawArrays(GL_QUAD_STRIP, 0, 4 * (fLOD + 1) + 8);
259  //4. draw top and bottom strips
260  glDrawArrays(GL_QUAD_STRIP, 4 * (fLOD + 1) + 8, 2 * (fLOD + 1));
261  glDrawArrays(GL_QUAD_STRIP, 6 * (fLOD + 1) + 8, 2 * (fLOD + 1));
262 
263  glDisableClientState(GL_VERTEX_ARRAY);
264  glDisableClientState(GL_NORMAL_ARRAY);
265 }
266 
267 ////////////////////////////////////////////////////////////////////////////////
268 /// constructor
269 
270 TubeMesh::TubeMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t r3, Double_t r4, Double_t z,
271  const TGLVector3 &l, const TGLVector3 &h)
272  :TGLMesh(LOD, r1, r2, r3, r4, z, l, h), fMesh(), fNorm()
273 {
274  const Double_t delta = TMath::TwoPi() / fLOD;
275  Double_t currAngle = 0.;
276 
277  Bool_t even = kTRUE;
278  Double_t c = TMath::Cos(currAngle);
279  Double_t s = TMath::Sin(currAngle);
280 
281  const Int_t topShift = (fLOD + 1) * 4;
282  const Int_t botShift = (fLOD + 1) * 6;
283  Int_t j = 4 * (fLOD + 1) - 2;
284 
285  //defining all four strips here
286  for (Int_t i = 0, e = (fLOD + 1) * 2; i < e; ++i) {
287  if (even) {
288  fMesh[i] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
289  fMesh[j] = MakeVertex(fRmin2 * c, fRmin2 * s, fDz);
290  fMesh[i + topShift] = MakeVertex(fRmin2 * c, fRmin2 * s, fDz);
291  fMesh[i + botShift] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
292  GetNormal(fMesh[j], fNorm[j]);
293  fNorm[j].Negate();
294  even = kFALSE;
295  } else {
296  fMesh[i] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
297  fMesh[j + 1] = MakeVertex(fRmin1 * c, fRmin1 * s, -fDz);
298  fMesh[i + topShift] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
299  fMesh[i + botShift] = MakeVertex(fRmin1 * c, fRmin1 * s, - fDz);
300  GetNormal(fMesh[j + 1], fNorm[j + 1]);
301  fNorm[j + 1].Negate();
302  even = kTRUE;
303  currAngle += delta;
304  c = TMath::Cos(currAngle);
305  s = TMath::Sin(currAngle);
306  j -= 2;
307  }
308 
309  GetNormal(fMesh[i], fNorm[i]);
310  fNorm[i + topShift] = fNhigh;
311  fNorm[i + botShift] = fNlow;
312  }
313 }
314 
315 ////////////////////////////////////////////////////////////////////////////////
316 ///Tube is drawn as four quad strips
317 
318 void TubeMesh::Draw() const
319 {
320  glEnableClientState(GL_VERTEX_ARRAY);
321  glEnableClientState(GL_NORMAL_ARRAY);
322 
323  glVertexPointer(3, GL_DOUBLE, sizeof(TGLVertex3), fMesh[0].CArr());
324  glNormalPointer(GL_DOUBLE, sizeof(TGLVector3), fNorm[0].CArr());
325  //draw outer and inner strips
326  glDrawArrays(GL_QUAD_STRIP, 0, 2 * (fLOD + 1));
327  glDrawArrays(GL_QUAD_STRIP, 2 * (fLOD + 1), 2 * (fLOD + 1));
328  //draw top and bottom strips
329  glDrawArrays(GL_QUAD_STRIP, 4 * (fLOD + 1), 2 * (fLOD + 1));
330  glDrawArrays(GL_QUAD_STRIP, 6 * (fLOD + 1), 2 * (fLOD + 1));
331  //5. disabling vertex arrays
332  glDisableClientState(GL_VERTEX_ARRAY);
333  glDisableClientState(GL_NORMAL_ARRAY);
334 }
335 
336 ////////////////////////////////////////////////////////////////////////////////
337 /// constructor
338 
339 TCylinderMesh::TCylinderMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t dz,
340  const TGLVector3 &l, const TGLVector3 &h)
341  :TGLMesh(LOD, 0., r1, 0., r2, dz, l, h), fMesh(), fNorm()
342 {
343  const Double_t delta = TMath::TwoPi() / fLOD;
344  Double_t currAngle = 0.;
345 
346  Bool_t even = kTRUE;
347  Double_t c = TMath::Cos(currAngle);
348  Double_t s = TMath::Sin(currAngle);
349 
350  //central point of top fan
351  Int_t topShift = (fLOD + 1) * 2;
352  fMesh[topShift][0] = fMesh[topShift][1] = 0., fMesh[topShift][2] = fDz;
353  fNorm[topShift] = fNhigh;
354  ++topShift;
355 
356  //central point of bottom fun
357  Int_t botShift = topShift + 2 * (fLOD + 1);
358  fMesh[botShift][0] = fMesh[botShift][1] = 0., fMesh[botShift][2] = -fDz;
359  fNorm[botShift] = fNlow;
360  ++botShift;
361 
362  //defining 1 strip and 2 fans
363  for (Int_t i = 0, e = (fLOD + 1) * 2, j = 0; i < e; ++i) {
364  if (even) {
365  fMesh[i] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
366  fMesh[j + topShift] = MakeVertex(fRmin2 * c, fRmin2 * s, fDz);
367  fMesh[j + botShift] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
368  even = kFALSE;
369  } else {
370  fMesh[i] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
371  even = kTRUE;
372  currAngle += delta;
373  c = TMath::Cos(currAngle);
374  s = TMath::Sin(currAngle);
375  ++j;
376  }
377 
378  GetNormal(fMesh[i], fNorm[i]);
379  fNorm[i + topShift] = fNhigh;
380  fNorm[i + botShift] = fNlow;
381  }
382 }
383 
384 ////////////////////////////////////////////////////////////////////////////////
385 /// draw cylinder mesh
386 
387 void TCylinderMesh::Draw() const
388 {
389  glEnableClientState(GL_VERTEX_ARRAY);
390  glEnableClientState(GL_NORMAL_ARRAY);
391 
392  glVertexPointer(3, GL_DOUBLE, sizeof(TGLVertex3), fMesh[0].CArr());
393  glNormalPointer(GL_DOUBLE, sizeof(TGLVector3), fNorm[0].CArr());
394 
395  //draw quad strip
396  glDrawArrays(GL_QUAD_STRIP, 0, 2 * (fLOD + 1));
397  //draw top and bottom funs
398  glDrawArrays(GL_TRIANGLE_FAN, 2 * (fLOD + 1), fLOD + 2);
399  glDrawArrays(GL_TRIANGLE_FAN, 3 * (fLOD + 1) + 1, fLOD + 2);
400 
401  glDisableClientState(GL_VERTEX_ARRAY);
402  glDisableClientState(GL_NORMAL_ARRAY);
403 }
404 
405 ////////////////////////////////////////////////////////////////////////////////
406 ///One quad mesh and two fans
407 
408 TCylinderSegMesh::TCylinderSegMesh(UInt_t LOD, Double_t r1, Double_t r2, Double_t dz, Double_t phi1,
409  Double_t phi2, const TGLVector3 &l,
410  const TGLVector3 &h)
411  :TGLMesh(LOD, 0., r1, 0., r2, dz, l, h), fMesh(), fNorm()
412 {
413  Double_t delta = (phi2 - phi1) / fLOD;
414  Double_t currAngle = phi1;
415 
416  Bool_t even = kTRUE;
417  Double_t c = TMath::Cos(currAngle);
418  Double_t s = TMath::Sin(currAngle);
419 
420  const TGLVertex3 vTop(0., 0., fDz);
421  const TGLVertex3 vBot(0., 0., - fDz);
422 
423  //center of top fan
424  Int_t topShift = (fLOD + 1) * 2 + 8;
425  fMesh[topShift] = vTop;
426  fNorm[topShift] = fNhigh;
427  ++topShift;
428 
429  //center of bottom fan
430  Int_t botShift = topShift + fLOD + 1;
431  fMesh[botShift] = vBot;
432  fNorm[botShift] = fNlow;
433  ++botShift;
434 
435  //defining strip and two fans
436  //strip is not closed here
437  Int_t i = 0;
438  for (Int_t e = (fLOD + 1) * 2, j = 0; i < e; ++i) {
439  if (even) {
440  fMesh[i] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
441  fMesh[j + topShift] = MakeVertex(fRmax2 * c, fRmax2 * s, fDz);
442  fMesh[j + botShift] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
443  even = kFALSE;
444  fNorm[j + topShift] = fNhigh;
445  fNorm[j + botShift] = fNlow;
446  } else {
447  fMesh[i] = MakeVertex(fRmax1 * c, fRmax1 * s, - fDz);
448  even = kTRUE;
449  currAngle += delta;
450  c = TMath::Cos(currAngle);
451  s = TMath::Sin(currAngle);
452  ++j;
453  }
454 
455  GetNormal(fMesh[i], fNorm[i]);
456  }
457 
458  //closing first strip
459  Int_t ind = 2 * (fLOD + 1);
460  TGLVector3 norm(0., 0., 0.);
461 
462  fMesh[ind] = fMesh[ind - 2];
463  fMesh[ind + 1] = fMesh[ind - 1];
464  fMesh[ind + 2] = vTop;
465  fMesh[ind + 3] = vBot;
466  TMath::Normal2Plane(fMesh[ind].CArr(), fMesh[ind + 1].CArr(), fMesh[ind + 2].CArr(),
467  norm.Arr());
468  fNorm[ind] = norm;
469  fNorm[ind + 1] = norm;
470  fNorm[ind + 2] = norm;
471  fNorm[ind + 3] = norm;
472 
473  ind += 4;
474  fMesh[ind] = vTop;
475  fMesh[ind + 1] = vBot;
476  fMesh[ind + 2] = fMesh[0];
477  fMesh[ind + 3] = fMesh[1];
478  TMath::Normal2Plane(fMesh[ind].CArr(), fMesh[ind + 1].CArr(), fMesh[ind + 2].CArr(),
479  norm.Arr());
480  fNorm[ind] = norm;
481  fNorm[ind + 1] = norm;
482  fNorm[ind + 2] = norm;
483  fNorm[ind + 3] = norm;
484 }
485 
486 ////////////////////////////////////////////////////////////////////////////////
487 ///Cylinder segment is drawn as one quad strip and
488 ///two triangle fans
489 ///1. enabling vertex arrays
490 
491 void TCylinderSegMesh::Draw() const
492 {
493  glEnableClientState(GL_VERTEX_ARRAY);
494  glEnableClientState(GL_NORMAL_ARRAY);
495  //2. setting arrays
496  glVertexPointer(3, GL_DOUBLE, sizeof(TGLVertex3), fMesh[0].CArr());
497  glNormalPointer(GL_DOUBLE, sizeof(TGLVector3), fNorm[0].CArr());
498  //3. draw quad strip
499  glDrawArrays(GL_QUAD_STRIP, 0, 2 * (fLOD + 1) + 8);
500  //4. draw top and bottom funs
501  glDrawArrays(GL_TRIANGLE_FAN, 2 * (fLOD + 1) + 8, fLOD + 2);
502  // glDrawArrays(GL_TRIANGLE_FAN, 3 * (fLOD + 1) + 9, fLOD + 2);
503  //5. disabling vertex arrays
504  glDisableClientState(GL_VERTEX_ARRAY);
505  glDisableClientState(GL_NORMAL_ARRAY);
506 }
507 
508 
509 /** \class TGLCylinder
510 \ingroup opengl
511 Implements a native ROOT-GL cylinder that can be rendered at
512 different levels of detail.
513 */
514 
515 ClassImp(TGLCylinder);
516 
517 ////////////////////////////////////////////////////////////////////////////////
518 /// Copy out relevant parts of buffer - we create and delete mesh
519 /// parts on demand in DirectDraw() and they are DL cached
520 
521 TGLCylinder::TGLCylinder(const TBuffer3DTube &buffer) :
522  TGLLogicalShape(buffer)
523 {
524  fDLSize = 14;
525 
526  fR1 = buffer.fRadiusInner;
527  fR2 = buffer.fRadiusOuter;
528  fR3 = buffer.fRadiusInner;
529  fR4 = buffer.fRadiusOuter;
530  fDz = buffer.fHalfLength;
531 
532  fLowPlaneNorm = gLowNormalDefault;
533  fHighPlaneNorm = gHighNormalDefault;
534 
535  switch (buffer.Type())
536  {
537  default:
538  case TBuffer3DTypes::kTube:
539  {
540  fSegMesh = kFALSE;
541  fPhi1 = 0;
542  fPhi2 = 360;
543  break;
544  }
545 
546  case TBuffer3DTypes::kTubeSeg:
547  case TBuffer3DTypes::kCutTube:
548  {
549  fSegMesh = kTRUE;
550 
551  const TBuffer3DTubeSeg * segBuffer = dynamic_cast<const TBuffer3DTubeSeg *>(&buffer);
552  if (!segBuffer) {
553  Error("TGLCylinder::TGLCylinder", "cannot cast TBuffer3D");
554  return;
555  }
556 
557  fPhi1 = segBuffer->fPhiMin;
558  fPhi2 = segBuffer->fPhiMax;
559  if (fPhi2 < fPhi1) fPhi2 += 360.;
560  fPhi1 *= TMath::DegToRad();
561  fPhi2 *= TMath::DegToRad();
562 
563  if (buffer.Type() == TBuffer3DTypes::kCutTube) {
564  const TBuffer3DCutTube * cutBuffer = dynamic_cast<const TBuffer3DCutTube *>(&buffer);
565  if (!cutBuffer) {
566  Error("TGLCylinder::TGLCylinder", "cannot cast TBuffer3D");
567  return;
568  }
569 
570  for (UInt_t i =0; i < 3; i++) {
571  fLowPlaneNorm[i] = cutBuffer->fLowPlaneNorm[i];
572  fHighPlaneNorm[i] = cutBuffer->fHighPlaneNorm[i];
573  }
574  }
575  break;
576  }
577  }
578 }
579 
580 ////////////////////////////////////////////////////////////////////////////////
581 ///destructor
582 
583 TGLCylinder::~TGLCylinder()
584 {
585 }
586 
587 ////////////////////////////////////////////////////////////////////////////////
588 /// Return display-list offset for given LOD.
589 /// Calculation based on what is done in virtual QuantizeShapeLOD below.
590 
591 UInt_t TGLCylinder::DLOffset(Short_t lod) const
592 {
593  UInt_t off = 0;
594  if (lod >= 100) off = 0;
595  else if (lod < 10) off = lod / 2;
596  else off = lod / 10 + 4;
597  return off;
598 }
599 
600 ////////////////////////////////////////////////////////////////////////////////
601 /// Factor in scene/viewer LOD and quantize.
602 
603 Short_t TGLCylinder::QuantizeShapeLOD(Short_t shapeLOD, Short_t combiLOD) const
604 {
605  Int_t lod = ((Int_t)shapeLOD * (Int_t)combiLOD) / 100;
606 
607  if (lod >= 100)
608  {
609  lod = 100;
610  }
611  else if (lod > 10)
612  { // Round LOD above 10 to nearest 10
613  Double_t quant = 0.1 * ((static_cast<Double_t>(lod)) + 0.5);
614  lod = 10 * static_cast<Int_t>(quant);
615  }
616  else
617  { // Round LOD below 10 to nearest 2
618  Double_t quant = 0.5 * ((static_cast<Double_t>(lod)) + 0.5);
619  lod = 2 * static_cast<Int_t>(quant);
620  }
621  return static_cast<Short_t>(lod);
622 }
623 
624 ////////////////////////////////////////////////////////////////////////////////
625 /// Debug tracing
626 
627 void TGLCylinder::DirectDraw(TGLRnrCtx & rnrCtx) const
628 {
629  if (gDebug > 4) {
630  Info("TGLCylinder::DirectDraw", "this %ld (class %s) LOD %d",
631  (Long_t)this, IsA()->GetName(), rnrCtx.ShapeLOD());
632  }
633 
634  // As we are now support display list caching we can create, draw and
635  // delete mesh parts of suitable LOD (quality) here - it will be cached
636  // into a display list by base-class TGLLogicalShape::Draw(),
637  // against our id and the LOD value. So this will only occur once
638  // for a certain cylinder/LOD combination
639  std::vector<TGLMesh *> meshParts;
640 
641  // Create mesh parts
642  if (!fSegMesh) {
643  meshParts.push_back(new TubeMesh (rnrCtx.ShapeLOD(), fR1, fR2, fR3, fR4,
644  fDz, fLowPlaneNorm, fHighPlaneNorm));
645  } else {
646  meshParts.push_back(new TubeSegMesh(rnrCtx.ShapeLOD(), fR1, fR2, fR3, fR4,
647  fDz, fPhi1, fPhi2,
648  fLowPlaneNorm, fHighPlaneNorm));
649  }
650 
651  // Draw mesh parts
652  for (UInt_t i = 0; i < meshParts.size(); ++i) meshParts[i]->Draw();
653 
654  // Delete mesh parts
655  for (UInt_t i = 0; i < meshParts.size(); ++i) {
656  delete meshParts[i];
657  meshParts[i] = 0;//not to have invalid pointer for pseudo-destructor call :)
658  }
659 }