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Geo_BicubicBezierPatch.h
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1 #ifndef SimTK_SIMMATH_GEO_BICUBIC_BEZIER_PATCH_H_
2 #define SimTK_SIMMATH_GEO_BICUBIC_BEZIER_PATCH_H_
3 
4 /* -------------------------------------------------------------------------- *
5  * Simbody(tm): SimTKmath *
6  * -------------------------------------------------------------------------- *
7  * This is part of the SimTK biosimulation toolkit originating from *
8  * Simbios, the NIH National Center for Physics-Based Simulation of *
9  * Biological Structures at Stanford, funded under the NIH Roadmap for *
10  * Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody. *
11  * *
12  * Portions copyright (c) 2011-12 Stanford University and the Authors. *
13  * Authors: Michael Sherman *
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26 
31 #include "SimTKcommon.h"
33 #include "simmath/internal/Geo.h"
35 
36 #include <cassert>
37 #include <cmath>
38 #include <algorithm>
39 
40 namespace SimTK {
41 
42 
43 //==============================================================================
44 // GEO BICUBIC BEZIER PATCH
45 //==============================================================================
100 template <class P>
101 class Geo::BicubicBezierPatch_ {
102 typedef P RealP;
103 typedef Vec<3,RealP> Vec3P;
104 
105 public:
108 
113 explicit BicubicBezierPatch_(const Mat<4,4,Vec3P>& controlPoints)
114 : B(controlPoints) {}
115 
116 
120 Vec3P evalP(RealP u, RealP w) const {return evalPUsingB(B,u,w);}
121 
125 void evalP1(RealP u, RealP w, Vec3P& Pu, Vec3P& Pw) const
126 { return evalP1UsingB(B,u,w,Pu,Pw); }
127 
132 void evalP2(RealP u, RealP w, Vec3P& Puu, Vec3P& Puw, Vec3P& Pww) const
133 { evalP2UsingB(B,u,w,Puu,Puw,Pww); }
134 
139 void evalP3(RealP u, RealP w, Vec3P& Puuu, Vec3P& Puuw,
140  Vec3P& Puww, Vec3P& Pwww) const
141 { evalP3UsingB(B,u,w,Puuu,Puuw,Puww,Pwww); }
142 
146 const Mat<4,4,Vec3P>& getControlPoints() const {return B;}
159 
164 { return CubicBezierCurve_<P>(B[0]); } // b11 b12 b13 b14
169 { return CubicBezierCurve_<P>(B[3]); } // b41 b42 b43 b44
174 { return CubicBezierCurve_<P>(B(0)); } // b11 b21 b31 b41
179 { return CubicBezierCurve_<P>(B(3)); } // b14 b24 b34 b44
180 
185 { return calcIsoCurveU(B, u0); }
190 { return calcIsoCurveW(B, w0); }
191 
206 void splitU(RealP u, BicubicBezierPatch_<P>& patch0,
207  BicubicBezierPatch_<P>& patch1) const {
208  const RealP tol = getDefaultTol<RealP>();
209  SimTK_ERRCHK1(tol <= u && u <= 1-tol, "Geo::BicubicBezierPatch::splitU()",
210  "Can't split patch at parameter u=%g; it is either out of range or"
211  " too close to an edge.", (double)u);
213  if (u==RealP(0.5)) // bisecting
214  for (int i=0; i<4; ++i) {
215  CubicBezierCurve_<P>(B(i)).bisect(l,h);
216  patch0.B(i) = l.getControlPoints();
217  patch1.B(i) = h.getControlPoints();
218  }
219  else
220  for (int i=0; i<4; ++i) {
221  CubicBezierCurve_<P>(B(i)).split(u,l,h);
222  patch0.B(i) = l.getControlPoints();
223  patch1.B(i) = h.getControlPoints();
224  }
225 }
226 
241 void splitW(RealP w, BicubicBezierPatch_<P>& patch0,
242  BicubicBezierPatch_<P>& patch1) const {
243  const RealP tol = getDefaultTol<RealP>();
244  SimTK_ERRCHK1(tol <= w && w <= 1-tol, "Geo::BicubicBezierPatch::splitW()",
245  "Can't split patch at parameter w=%g; it is either out of range or"
246  " too close to an edge.", (double)w);
248  if (w==RealP(0.5)) // bisecting
249  for (int i=0; i<4; ++i) {
250  CubicBezierCurve_<P>(B[i]).bisect(l,h);
251  patch0.B[i] = l.getControlPoints().positionalTranspose();
252  patch1.B[i] = h.getControlPoints().positionalTranspose();
253  }
254  else
255  for (int i=0; i<4; ++i) {
256  CubicBezierCurve_<P>(B[i]).split(w,l,h);
257  patch0.B[i] = l.getControlPoints().positionalTranspose();
258  patch1.B[i] = h.getControlPoints().positionalTranspose();
259  }
260 }
261 
262 
278 void split(RealP u, RealP w, BicubicBezierPatch_<P>& patch00,
279  BicubicBezierPatch_<P>& patch01,
280  BicubicBezierPatch_<P>& patch10,
281  BicubicBezierPatch_<P>& patch11) const {
282  const RealP tol = getDefaultTol<RealP>();
283  SimTK_ERRCHK2((tol <= u && u <= 1-tol) && (tol <= w && w <= 1-tol),
284  "Geo::BicubicBezierPatch::split()",
285  "Can't split patch at parametric point u,w=%g,%g; it is either out of"
286  " range or too close to an edge.", (double)u, (double)w);
287 
288  BicubicBezierPatch_<P> patch0, patch1; // results of the first split
289 
290  // We split once along one direction, and then twice along the other, so
291  // make sure the second direction is the cheap bisecting one.
292  if (u == Real(0.5)) {
293  splitW(w,patch0,patch1); // 120 or 180 flops
294  patch0.splitU(u, patch00, patch10); // 120 flops
295  patch1.splitU(u, patch01, patch11); // 120 flops
296  } else {
297  splitU(u,patch0,patch1); // 180 flops
298  patch0.splitW(w, patch00, patch01); // 120 or 180 flops
299  patch1.splitW(w, patch10, patch11); // 120 or 180 flops
300  }
301 }
302 
311 { const ArrayViewConst_<Vec3P> points(&B(0,0), &B(0,0)+16); // no copy
312  return Geo::Point_<P>::calcBoundingSphere(points); }
313 
322 { const ArrayViewConst_<Vec3P> points(&B(0,0), &B(0,0)+16); // no copy
324 
333 { const ArrayViewConst_<Vec3P> points(&B(0,0), &B(0,0)+16); // no copy
335 
344 static Vec3P evalPUsingB(const Mat<4,4,Vec3P>& B, RealP u, RealP w) {
345  Row<4,P> Fbu = CubicBezierCurve_<P>::calcFb(u); // 9 flops
346  Row<4,P> Fbw = CubicBezierCurve_<P>::calcFb(w); // 9 flops
347  return Fbu * B * ~Fbw; // 3x35 flops
348 }
349 
354 static void evalP1UsingB(const Mat<4,4,Vec3P>& B, RealP u, RealP w,
355  Vec3P& Pu, Vec3P& Pw) {
356  Row<4,P> Fbu = CubicBezierCurve_<P>::calcFb(u); // 9 flops
357  Row<4,P> Fbw = CubicBezierCurve_<P>::calcFb(w); // 9 flops
358  Row<4,P> dFbu = CubicBezierCurve_<P>::calcDFb(u); // 10 flops
359  Row<4,P> dFbw = CubicBezierCurve_<P>::calcDFb(w); // 10 flops
360  Pu = dFbu * B * ~Fbw; // 3x35
361  Pw = Fbu * B * ~dFbw; // 3x35
362 }
363 
368 static void evalP2UsingB(const Mat<4,4,Vec3P>& B, RealP u, RealP w,
369  Vec3P& Puu, Vec3P& Puw, Vec3P& Pww) {
370  Row<4,P> Fbu = CubicBezierCurve_<P>::calcFb(u); // 9 flops
371  Row<4,P> Fbw = CubicBezierCurve_<P>::calcFb(w); // 9 flops
372  Row<4,P> dFbu = CubicBezierCurve_<P>::calcDFb(u); // 10 flops
373  Row<4,P> dFbw = CubicBezierCurve_<P>::calcDFb(w); // 10 flops
374  Row<4,P> d2Fbu = CubicBezierCurve_<P>::calcD2Fb(u); // 5 flops
375  Row<4,P> d2Fbw = CubicBezierCurve_<P>::calcD2Fb(w); // 5 flops
376  Puu = d2Fbu * B * ~Fbw; // 3x35
377  Puw = dFbu * B * ~dFbw; // 3x35
378  Pww = Fbu * B * ~d2Fbw; // 3x35
379 }
380 
385 static void evalP3UsingB(const Mat<4,4,Vec3P>& B, RealP u, RealP w,
386  Vec3P& Puuu, Vec3P& Puuw, Vec3P& Puww, Vec3P& Pwww) {
387  Row<4,P> Fbu = CubicBezierCurve_<P>::calcFb(u); // 9 flops
388  Row<4,P> Fbw = CubicBezierCurve_<P>::calcFb(w); // 9 flops
389  Row<4,P> dFbu = CubicBezierCurve_<P>::calcDFb(u); // 10 flops
390  Row<4,P> dFbw = CubicBezierCurve_<P>::calcDFb(w); // 10 flops
391  Row<4,P> d2Fbu = CubicBezierCurve_<P>::calcD2Fb(u); // 5 flops
392  Row<4,P> d2Fbw = CubicBezierCurve_<P>::calcD2Fb(w); // 5 flops
393  Row<4,P> d3Fbu = CubicBezierCurve_<P>::calcD3Fb(u); // 0
395  Puuu = d3Fbu * B * ~Fbw; // 3x35
396  Puuw = d2Fbu * B * ~dFbw; // 3x35
397  Puww = dFbu * B * ~d2Fbw; // 3x35
398  Pwww = Fbu * B * ~d3Fbw; // 3x35
399 }
400 
404 static CubicBezierCurve_<P>
405 calcIsoCurveU(const Mat<4,4,Vec3P>& B, RealP u0)
406 { const Row<4,Vec3P> Bu0 = CubicBezierCurve_<P>::calcFb(u0) * B;
407  return CubicBezierCurve_<P>(Bu0); }
408 
412 static CubicBezierCurve_<P>
413 calcIsoCurveW(const Mat<4,4,Vec3P>& B, RealP w0)
414 { const Vec<4,Vec3P> Bw0 = B * ~CubicBezierCurve_<P>::calcFb(w0);
415  return CubicBezierCurve_<P>(Bw0); }
416 
420  typedef const Vec3P& Coef;
421  Coef b11=B(0,0), b12=B(0,1), b13=B(0,2), b14=B(0,3),
422  b21=B(1,0), b22=B(1,1), b23=B(1,2), b24=B(1,3),
423  b31=B(2,0), b32=B(2,1), b33=B(2,2), b34=B(2,3),
424  b41=B(3,0), b42=B(3,1), b43=B(3,2), b44=B(3,3);
425  // First calculate Mb*B:
426  // a b c d
427  // e f g h
428  // p q r s
429  // b11 b12 b13 b14
430  Vec3P a= b41-b11+3*(b21-b31), b= b42-b12+3*(b22-b32), // 3x16 flops
431  c= b43-b13+3*(b23-b33), d= b44-b14+3*(b24-b34);
432  Vec3P e= 3*(b11+b31)-6*b21, f= 3*(b12+b32)-6*b22, // 3x16 flops
433  g= 3*(b13+b33)-6*b23, h= 3*(b14+b34)-6*b24;
434  Vec3P p= 3*(b21-b11), q= 3*(b22-b12), // 3x8 flops
435  r= 3*(b23-b13), s= 3*(b24-b14);
436 
437  // Then calculate (Mb*B)*~Mb. (3x40 more flops)
438  return Mat<4,4,Vec3P>
439  ( d-a+3*(b-c), 3*(a+c)-6*b, 3*(b-a), a,
440  h-e+3*(f-g), 3*(e+g)-6*f, 3*(f-e), e,
441  s-p+3*(q-r), 3*(p+r)-6*q, 3*(q-p), p,
442  b14-b11+3*(b12-b13), 3*(b11+b13)-6*b12, 3*(b12-b11), b11 );
443 }
444 
448  typedef const Vec3P& Coef;
449  Coef a33=A(0,0), a32=A(0,1), a31=A(0,2), a30=A(0,3),
450  a23=A(1,0), a22=A(1,1), a21=A(1,2), a20=A(1,3),
451  a13=A(2,0), a12=A(2,1), a11=A(2,2), a10=A(2,3),
452  a03=A(3,0), a02=A(3,1), a01=A(3,2), a00=A(3,3);
453  // First calculate Mb^-1*A:
454  // a03 a02 a01 a00
455  // a b c d
456  // e f g h
457  // p q r s
458  Vec3P a=a13/3+a03, b=a12/3+a02, c=a11/3+a01, d=a10/3+a00; // 3x8 flops
459  Vec3P e=(a23+2*a13)/3+a03, f=(a22+2*a12)/3+a02, // 3x16 flops
460  g=(a21+2*a11)/3+a01, h=(a20+2*a10)/3+a00;
461  Vec3P p=a33+a23+a13+a03, q=a32+a22+a12+a02, // 3x12 flops
462  r=a31+a21+a11+a01, s=a30+a20+a10+a00;
463 
464 
465  // Then calculate (Mb^-1*A)*Mb^-T (3x36 more flops)
466  return Mat<4,4,Vec3P>
467  ( a00, a01/3+a00, (a02+2*a01)/3+a00, a03+a02+a01+a00,
468  d, c/3+d, (b+2*c)/3+d, a+b+c+d,
469  h, g/3+h, (f+2*g)/3+h, e+f+g+h,
470  s, r/3+s, (q+2*r) /3+s, p+q+r+s );
471 }
472 
476  typedef const Vec3P& Coef;
477  Coef b11=B(0,0), b12=B(0,1), b13=B(0,2), b14=B(0,3),
478  b21=B(1,0), b22=B(1,1), b23=B(1,2), b24=B(1,3),
479  b31=B(2,0), b32=B(2,1), b33=B(2,2), b34=B(2,3),
480  b41=B(3,0), b42=B(3,1), b43=B(3,2), b44=B(3,3);
481 
482  // First calculate a few temps -- see class comments. (3x4 flops)
483  Vec3P b12mb11=b12-b11, b24mb14=b24-b14, b42mb41=b42-b41, b44mb34=b44-b34;
484 
485  // Then calculate (Mh^-1 Mb) B ~(Mh^-1 Mb). (3x24 more flops)
486  return Mat<4,4,Vec3P>
487  ( b11, b14, 3*b12mb11, 3*(b14-b13),
488  b41, b44, 3*b42mb41, 3*(b44-b43),
489  3*(b21-b11), 3*b24mb14, 9*(b22-b21-b12mb11), 9*(b24mb14+b13-b23),
490  3*(b41-b31), 3*b44mb34, 9*(b42mb41+b31-b32), 9*(b44mb34+b33-b43) );
491 }
492 
496  typedef const Vec3P& Coef;
497  Coef h00=H(0,0), h01=H(0,1), w00=H(0,2), w01=H(0,3),
498  h10=H(1,0), h11=H(1,1), w10=H(1,2), w11=H(1,3),
499  u00=H(2,0), u01=H(2,1), t00=H(2,2), t01=H(2,3),
500  u10=H(3,0), u11=H(3,1), t10=H(3,2), t11=H(3,3);
501 
502  // First calculate a few temps -- see class comments. (3x8 flops)
503  Vec3P tmp00=h00+u00/3, tmp01=h01+u01/3,
504  tmp10=h10-u10/3, tmp11=h11-u11/3;
505 
506  // Then calculate (Mb^-1 Mh) H ~(Mb^-1 Mh). (3x24 more flops)
507  return Mat<4,4,Vec3P>
508  ( h00, h00+w00/3, h01-w01/3, h01,
509  tmp00, tmp00+w00/3+t00/9, tmp01-w01/3-t01/9, tmp01,
510  tmp10, tmp10+w10/3-t10/9, tmp11-w11/3+t11/9, tmp11,
511  h10, h10+w10/3, h11-w11/3, h11 );
512 }
515 private:
516 Mat<4,4,Vec3P> B; // 16 Bezier control points; see above for definition
517 };
518 
519 
520 
521 } // namespace SimTK
522 
523 #endif // SimTK_SIMMATH_GEO_BICUBIC_BEZIER_PATCH_H_
This Array_ helper class is the base class for ArrayView_ which is the base class for Array_; here we...
Definition: Array.h:48
static CubicBezierCurve_< P > calcIsoCurveU(const Mat< 4, 4, Vec3P > &B, RealP u0)
Given a particular value u0 for patch coordinate u, create a cubic Bezier curve segment P(w)=P(u0...
Definition: Geo_BicubicBezierPatch.h:405
static Mat< 4, 4, Vec3P > calcBFromH(const Mat< 4, 4, Vec3P > &H)
Given the vector Hermite coefficients H, return the equivalent Bezier control points B...
Definition: Geo_BicubicBezierPatch.h:495
A 3d box aligned with an unspecified frame F and centered at a given point measured from that frame's...
Definition: Geo.h:62
static Sphere_< P > calcBoundingSphere(const Vec3P &p)
Create a tiny bounding sphere around a single point.
Definition: Geo_Point.h:333
const Vec< 4, Vec3P > & getControlPoints() const
Return a reference to the Bezier control points B=[b0 b1 b2 b3] that are stored in this object...
Definition: Geo_CubicBezierCurve.h:162
static Mat< 4, 4, Vec3P > calcBFromA(const Mat< 4, 4, Vec3P > &A)
Given the vector algebraic coefficients A, return the equivalent Bezier control points B...
Definition: Geo_BicubicBezierPatch.h:447
CubicBezierCurve_< P > calcIsoCurveU(RealP u0) const
Given a particular value u0 for patch coordinate u, create a cubic Bezier curve segment P(w)=P(u0...
Definition: Geo_BicubicBezierPatch.h:184
CubicBezierCurve_< P > getBoundaryCurveW1() const
Return the w=1 boundary curve as a Bezier curve segment.
Definition: Geo_BicubicBezierPatch.h:178
CubicBezierCurve_< P > calcIsoCurveW(RealP w0) const
Given a particular value w0 for patch coordinate w, create a cubic Bezier curve segment P(u)=P(u...
Definition: Geo_BicubicBezierPatch.h:189
This is the top-level SimTK namespace into which all SimTK names are placed to avoid collision with o...
Definition: Assembler.h:37
static void evalP2UsingB(const Mat< 4, 4, Vec3P > &B, RealP u, RealP w, Vec3P &Puu, Vec3P &Puw, Vec3P &Pww)
Given Bezier control points B and values for the curve parameters u and w in [0..1], return the second derivatives Puu(u,w)=d2Fb(u)*B*~Fb(w), Puw(u,w)=dFb(u)*B*~dFb(w) and Pww(u,w)=Fb(u)*B*~d2Fb(w) at that location.
Definition: Geo_BicubicBezierPatch.h:368
A primitive useful for computations involving a single bicubic Bezier patch.
Definition: Geo.h:68
CubicBezierCurve_< P > getBoundaryCurveU1() const
Return the u=1 boundary curve as a Bezier curve segment.
Definition: Geo_BicubicBezierPatch.h:168
void evalP1(RealP u, RealP w, Vec3P &Pu, Vec3P &Pw) const
Evaluate the tangents Pu=dP/du, Pw=dP/dw on this patch given values for the parameters u and w in [0...
Definition: Geo_BicubicBezierPatch.h:125
#define SimTK_ERRCHK1(cond, whereChecked, fmt, a1)
Definition: ExceptionMacros.h:326
void splitW(RealP w, BicubicBezierPatch_< P > &patch0, BicubicBezierPatch_< P > &patch1) const
Split this patch into two along the w direction, along an isoparametric curve of constant w=t such th...
Definition: Geo_BicubicBezierPatch.h:241
void evalP2(RealP u, RealP w, Vec3P &Puu, Vec3P &Puw, Vec3P &Pww) const
Evaluate the second derivatives Puu=d2P/du2, Pww=d2P/dw2, and cross derivative Puw=Pwu=d2P/dudw on th...
Definition: Geo_BicubicBezierPatch.h:132
SimTK_Real Real
This is the default compiled-in floating point type for SimTK, either float or double.
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:577
void evalP3(RealP u, RealP w, Vec3P &Puuu, Vec3P &Puuw, Vec3P &Puww, Vec3P &Pwww) const
Evaluate the third derivatives Puuu=d3P/du3, Pwww=d3P/dw3, and cross derivatives Puuw=Pwuu=Puwu=d3P/d...
Definition: Geo_BicubicBezierPatch.h:139
Mat< 4, 4, Vec3P > & updControlPoints()
Return a writable reference to the Bezier control points B that are stored in this object...
Definition: Geo_BicubicBezierPatch.h:150
static Mat< 4, 4, Vec3P > calcHFromB(const Mat< 4, 4, Vec3P > &B)
Given the Bezier control points B, return the equivalent vector Hermite coefficients H...
Definition: Geo_BicubicBezierPatch.h:475
Vec3P evalP(RealP u, RealP w) const
Evaluate a point P(u,w) on this patch given values for the parameters u and w in [0,1].
Definition: Geo_BicubicBezierPatch.h:120
Mat< 4, 4, Vec3P > calcAlgebraicCoefficients() const
Calculate the algebraic coefficients A from the stored Bezier control points.
Definition: Geo_BicubicBezierPatch.h:154
Mat< 4, 4, Vec3P > calcHermiteCoefficients() const
Calculate the Hermite coefficients H from the stored Bezier control points.
Definition: Geo_BicubicBezierPatch.h:158
CubicBezierCurve_< P > getBoundaryCurveU0() const
Return the u=0 boundary curve as a Bezier curve segment.
Definition: Geo_BicubicBezierPatch.h:163
Geo::AlignedBox_< P > calcAxisAlignedBoundingBox() const
Return an axis-aligned bounding box (AABB) that surrounds the entire patch segment in the 0<= u...
Definition: Geo_BicubicBezierPatch.h:321
BicubicBezierPatch_()
Construct an uninitialized patch; control points will be garbage.
Definition: Geo_BicubicBezierPatch.h:107
This is a primitive useful for computations involving a single cubic Bezier curve segment...
Definition: Geo.h:67
static Row< 4, P > calcD3Fb(RealP u)
Calculate third derivatives d3Fb=[B0uuu..B3uuu] of the Bernstein basis functions for a given value of...
Definition: Geo_CubicBezierCurve.h:351
Includes internal headers providing declarations for the basic SimTK Core classes, including Simmatrix.
static Geo::AlignedBox_< P > calcAxisAlignedBoundingBox(const Array_< Vec3P > &points, Array_< int > &support)
Calculate the smallest axis-aligned bounding box including all n given points.
static Geo::OrientedBox_< P > calcOrientedBoundingBox(const Array_< Vec3P > &points, Array_< int > &support, bool optimize=true)
Calculate a tight-fitting oriented bounding box (OBB) that includes all n given points.
static Row< 4, P > calcD2Fb(RealP u)
Calculate second derivatives d2Fb=[B0uu..B3uu] of the Bernstein basis functions for a given value of ...
Definition: Geo_CubicBezierCurve.h:343
Defines geometric primitive shapes and algorthms.
Provides primitive operations for a single bicubic Bezier curve using either single or double precisi...
static Row< 4, P > calcFb(RealP u)
Calculate the Bernstein basis functions Fb=[B0..B3] for a given value of the parameter u...
Definition: Geo_CubicBezierCurve.h:328
static Vec3P evalPUsingB(const Mat< 4, 4, Vec3P > &B, RealP u, RealP w)
Given Bezier control points B and values for the curve parameters u and w in [0..1], return the point P(u,w)=Fb(u)*B*~Fb(w) at that location, where Fb is a vector of Bezier basis functions.
Definition: Geo_BicubicBezierPatch.h:344
static Row< 4, P > calcDFb(RealP u)
Calculate first derivatives dFb=[B0u..B3u] of the Bernstein basis functions for a given value of the ...
Definition: Geo_CubicBezierCurve.h:336
static void evalP3UsingB(const Mat< 4, 4, Vec3P > &B, RealP u, RealP w, Vec3P &Puuu, Vec3P &Puuw, Vec3P &Puww, Vec3P &Pwww)
Given Bezier control points B and values for the curve parameters u and w in [0..1], return the third derivatives Puuu(u,w)=d3Fb(u)*B*~Fb(w), Puuw(u,w)=d2Fb(u)*B*~dFb(w), Puww(u,w)=dFb(u)*B*~d2Fb(w) and Pwww(u,w)=Fb(u)*B*~d3Fb(w) at that location.
Definition: Geo_BicubicBezierPatch.h:385
This is a fixed-length row vector designed for no-overhead inline computation.
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:590
static Mat< 4, 4, Vec3P > calcAFromB(const Mat< 4, 4, Vec3P > &B)
Given the Bezier control points B, return the equivalent vector algebraic coefficients A...
Definition: Geo_BicubicBezierPatch.h:419
void split(RealP u, RealP w, BicubicBezierPatch_< P > &patch00, BicubicBezierPatch_< P > &patch01, BicubicBezierPatch_< P > &patch10, BicubicBezierPatch_< P > &patch11) const
Split this patch into four subpatches at a particular parametric point (u,w) such that 0 < u...
Definition: Geo_BicubicBezierPatch.h:278
A geometric primitive representing a sphere by its radius and center point, and a collection of spher...
Definition: Geo.h:56
TODO: A 3d box oriented and positioned with respect to an unspecified frame F.
Definition: Geo.h:63
#define SimTK_ERRCHK2(cond, whereChecked, fmt, a1, a2)
Definition: ExceptionMacros.h:328
This is the header file that every Simmath compilation unit should include first. ...
static void evalP1UsingB(const Mat< 4, 4, Vec3P > &B, RealP u, RealP w, Vec3P &Pu, Vec3P &Pw)
Given Bezier control points B and values for the curve parameters u and w in [0..1], return the tangents Pu(u,w)=dFb(u)*B*~Fb(w) and Pw(u,w)=Fb(u)*B*~dFb(w) at that location.
Definition: Geo_BicubicBezierPatch.h:354
This class represents a small matrix whose size is known at compile time, containing elements of any ...
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:591
Geo::OrientedBox_< P > calcOrientedBoundingBox() const
Return an oriented bounding box (OBB) that surrounds the entire curve segment in the 0<= u...
Definition: Geo_BicubicBezierPatch.h:332
const Mat< 4, 4, Vec3P > & getControlPoints() const
Return a reference to the Bezier control points B that are stored in this object. ...
Definition: Geo_BicubicBezierPatch.h:146
This is a fixed-length column vector designed for no-overhead inline computation. ...
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:589
CubicBezierCurve_< P > getBoundaryCurveW0() const
Return the w=0 boundary curve as a Bezier curve segment.
Definition: Geo_BicubicBezierPatch.h:173
BicubicBezierPatch_(const Mat< 4, 4, Vec3P > &controlPoints)
Construct a bicubic Bezier patch using the given control points B.
Definition: Geo_BicubicBezierPatch.h:113
static CubicBezierCurve_< P > calcIsoCurveW(const Mat< 4, 4, Vec3P > &B, RealP w0)
Given a particular value w0 for patch coordinate w, create a cubic Bezier curve segment P(u)=P(u...
Definition: Geo_BicubicBezierPatch.h:413
void splitU(RealP u, BicubicBezierPatch_< P > &patch0, BicubicBezierPatch_< P > &patch1) const
Split this patch into two along the u direction, along an isoparametric curve of constant u=t such th...
Definition: Geo_BicubicBezierPatch.h:206
Geo::Sphere_< P > calcBoundingSphere() const
Return a sphere that surrounds the entire patch in the 0<= u,w <=1 range.
Definition: Geo_BicubicBezierPatch.h:310