[Bf-blender-cvs] [4b9771a] hair_immediate_fixes: Switched to the modified CG method that supports constraints, and added back structural stretch springs.
Lukas Tönne
noreply at git.blender.org
Mon Sep 8 19:02:53 CEST 2014
Commit: 4b9771a7cb88d059aee57865cede6d7a5f94e729
Author: Lukas Tönne
Date: Mon Sep 8 19:03:39 2014 +0200
Branches: hair_immediate_fixes
https://developer.blender.org/rB4b9771a7cb88d059aee57865cede6d7a5f94e729
Switched to the modified CG method that supports constraints, and
added back structural stretch springs.
===================================================================
M source/blender/blenkernel/intern/implicit_eigen.cpp
===================================================================
diff --git a/source/blender/blenkernel/intern/implicit_eigen.cpp b/source/blender/blenkernel/intern/implicit_eigen.cpp
index 5be6623..26bfa49 100644
--- a/source/blender/blenkernel/intern/implicit_eigen.cpp
+++ b/source/blender/blenkernel/intern/implicit_eigen.cpp
@@ -31,9 +31,17 @@
#define IMPLICIT_SOLVER_EIGEN
+//#define USE_EIGEN_CORE
+#define USE_EIGEN_CONSTRAINED_CG
+
#ifdef IMPLICIT_SOLVER_EIGEN
#include <Eigen/Sparse>
+#include <Eigen/src/Core/util/DisableStupidWarnings.h>
+
+#ifdef USE_EIGEN_CONSTRAINED_CG
+#include <intern/ConstrainedConjugateGradient.h>
+#endif
#include "MEM_guardedalloc.h"
@@ -54,7 +62,6 @@ extern "C" {
#include "BKE_global.h"
}
-
/* ==== hash functions for debugging ==== */
static unsigned int hash_int_2d(unsigned int kx, unsigned int ky)
{
@@ -100,10 +107,16 @@ typedef Eigen::VectorXf lVector;
typedef Eigen::Triplet<Scalar> Triplet;
typedef std::vector<Triplet> TripletList;
+#ifdef USE_EIGEN_CORE
typedef Eigen::ConjugateGradient<lMatrix, Eigen::Lower, Eigen::DiagonalPreconditioner<Scalar> > ConjugateGradient;
+#endif
+#ifdef USE_EIGEN_CONSTRAINED_CG
+typedef Eigen::ConstrainedConjugateGradient<lMatrix, Eigen::Lower, lMatrix,
+ Eigen::DiagonalPreconditioner<Scalar> >
+ ConstraintConjGrad;
+#endif
using Eigen::ComputationInfo;
-
static void print_lvector(const lVector &v)
{
for (int i = 0; i < v.rows(); ++i) {
@@ -115,14 +128,16 @@ static void print_lmatrix(const lMatrix &m)
{
for (int j = 0; j < m.rows(); ++j) {
for (int i = 0; i < m.cols(); ++i) {
- printf("%-16f,", m.coeff(j, i));
+ printf("%-8.3f,", m.coeff(j, i));
}
printf("\n");
}
}
+static float I[3][3] = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}};
+static float ZERO[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};
-BLI_INLINE void reserve_diagonal(lMatrix &m, int num)
+BLI_INLINE void lMatrix_reserve_elems(lMatrix &m, int num)
{
m.reserve(Eigen::VectorXi::Constant(m.cols(), num));
}
@@ -137,6 +152,59 @@ BLI_INLINE const float *lVector_v3(const lVector &v, int vertex)
return v.data() + 3 * vertex;
}
+BLI_INLINE void lMatrix_copy_m3(lMatrix &r, float m[3][3], int i, int j)
+{
+ i *= 3;
+ j *= 3;
+ for (int l = 0; l < 3; ++l) {
+ for (int k = 0; k < 3; ++k) {
+ r.coeffRef(i + k, j + l) = m[k][l];
+ }
+ }
+}
+
+BLI_INLINE void lMatrix_add_m3(lMatrix &r, float m[3][3], int i, int j)
+{
+ lMatrix tmp(r.cols(), r.cols());
+ if (i == j) {
+ lMatrix_copy_m3(tmp, m, i, i);
+ }
+ else {
+ lMatrix_copy_m3(tmp, m, i, j);
+ lMatrix_copy_m3(tmp, m, j, i);
+ }
+
+ r += tmp;
+}
+
+BLI_INLINE void lMatrix_sub_m3(lMatrix &r, float m[3][3], int i, int j)
+{
+ lMatrix tmp(r.cols(), r.cols());
+ if (i == j) {
+ lMatrix_copy_m3(tmp, m, i, i);
+ }
+ else {
+ lMatrix_copy_m3(tmp, m, i, j);
+ lMatrix_copy_m3(tmp, m, j, i);
+ }
+
+ r -= tmp;
+}
+
+BLI_INLINE void lMatrix_madd_m3(lMatrix &r, float m[3][3], float s, int i, int j)
+{
+ lMatrix tmp(r.cols(), r.cols());
+ if (i == j) {
+ lMatrix_copy_m3(tmp, m, i, i);
+ }
+ else {
+ lMatrix_copy_m3(tmp, m, i, j);
+ lMatrix_copy_m3(tmp, m, j, i);
+ }
+
+ r += s * tmp;
+}
+
BLI_INLINE void triplets_m3(TripletList &t, float m[3][3], int i, int j)
{
i *= 3;
@@ -148,6 +216,13 @@ BLI_INLINE void triplets_m3(TripletList &t, float m[3][3], int i, int j)
}
}
+BLI_INLINE void outerproduct(float r[3][3], const float a[3], const float b[3])
+{
+ mul_v3_v3fl(r[0], a, b[0]);
+ mul_v3_v3fl(r[1], a, b[1]);
+ mul_v3_v3fl(r[2], a, b[2]);
+}
+
struct Implicit_Data {
Implicit_Data(int numverts)
{
@@ -199,6 +274,7 @@ struct Implicit_Data {
static bool simulate_implicit_euler(Implicit_Data *id, float dt)
{
+#ifdef USE_EIGEN_CORE
ConjugateGradient cg;
cg.setMaxIterations(100);
cg.setTolerance(0.01f);
@@ -212,12 +288,62 @@ static bool simulate_implicit_euler(Implicit_Data *id, float dt)
id->Vnew = id->V + id->dV;
return cg.info() != Eigen::Success;
+#endif
+
+#ifdef USE_EIGEN_CONSTRAINED_CG
+ ConstraintConjGrad cg;
+ cg.setMaxIterations(100);
+ cg.setTolerance(0.01f);
+
+ id->A = id->M - dt * id->dFdV - dt*dt * id->dFdX;
+ cg.compute(id->A);
+ cg.filter() = id->S;
+
+ id->B = dt * id->F + dt*dt * id->dFdX * id->V;
+ id->dV = cg.solveWithGuess(id->B, id->z);
+
+ id->Vnew = id->V + id->dV;
+
+ return cg.info() != Eigen::Success;
+#endif
+}
+
+BLI_INLINE void dfdx_spring(float to[3][3], const float dir[3], float length, float L, float k)
+{
+ // dir is unit length direction, rest is spring's restlength, k is spring constant.
+ //return ( (I-outerprod(dir, dir))*Min(1.0f, rest/length) - I) * -k;
+ outerproduct(to, dir, dir);
+ sub_m3_m3m3(to, I, to);
+
+ mul_m3_fl(to, (L/length));
+ sub_m3_m3m3(to, to, I);
+ mul_m3_fl(to, -k);
+}
+
+/* unused */
+#if 0
+BLI_INLINE void dfdx_damp(float to[3][3], const float dir[3], float length, const float vel[3], float rest, float damping)
+{
+ // inner spring damping vel is the relative velocity of the endpoints.
+ // return (I-outerprod(dir, dir)) * (-damping * -(dot(dir, vel)/Max(length, rest)));
+ mul_fvectorT_fvector(to, dir, dir);
+ sub_fmatrix_fmatrix(to, I, to);
+ mul_fmatrix_S(to, (-damping * -(dot_v3v3(dir, vel)/MAX2(length, rest))));
+}
+#endif
+
+DO_INLINE void dfdv_damp(float to[3][3], const float dir[3], float damping)
+{
+ // derivative of force wrt velocity
+ outerproduct(to, dir, dir);
+ mul_m3_fl(to, damping);
}
static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, const lVector &X, const lVector &V, float time)
{
Cloth *cloth = clmd->clothObject;
ClothVertex *verts = cloth->verts;
+ ClothVertex *v1 = &verts[s->ij], *v2 = &verts[s->kl];
float extent[3];
float length = 0, dot = 0;
float dir[3] = {0, 0, 0};
@@ -228,7 +354,6 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
float stretch_force[3] = {0, 0, 0};
float bending_force[3] = {0, 0, 0};
- float damping_force[3] = {0, 0, 0};
float nulldfdx[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};
float scaling = 0.0;
@@ -239,14 +364,17 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
zero_m3(s->dfdx);
zero_m3(s->dfdv);
+ s->flags &= ~CLOTH_SPRING_FLAG_NEEDED;
+ /* ignore springs between pinned vertices */
+ if (v1->flags & CLOTH_VERT_FLAG_PINNED && v2->flags & CLOTH_VERT_FLAG_PINNED)
+ return;
+
// calculate elonglation
sub_v3_v3v3(extent, lVector_v3(X, s->kl), lVector_v3(X, s->ij));
sub_v3_v3v3(vel, lVector_v3(V, s->kl), lVector_v3(V, s->ij));
dot = dot_v3v3(extent, extent);
length = sqrt(dot);
- s->flags &= ~CLOTH_SPRING_FLAG_NEEDED;
-
if (length > ALMOST_ZERO) {
/*
if (length>L) {
@@ -264,18 +392,15 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
zero_v3(dir);
}
-#if 0
// calculate force of structural + shear springs
- if ((s->type & CLOTH_SPRING_TYPE_STRUCTURAL) || (s->type & CLOTH_SPRING_TYPE_SHEAR) || (s->type & CLOTH_SPRING_TYPE_SEWING) ) {
+ if (ELEM(s->type, CLOTH_SPRING_TYPE_STRUCTURAL, CLOTH_SPRING_TYPE_SHEAR, CLOTH_SPRING_TYPE_SEWING)) {
if (length > L || no_compress) {
s->flags |= CLOTH_SPRING_FLAG_NEEDED;
k = clmd->sim_parms->structural;
-
scaling = k + s->stiffness * fabsf(clmd->sim_parms->max_struct - k);
k = scaling / (clmd->sim_parms->avg_spring_len + FLT_EPSILON);
-
// TODO: verify, half verified (couldn't see error)
if (s->type & CLOTH_SPRING_TYPE_SEWING) {
// sewing springs usually have a large distance at first so clamp the force so we don't get tunnelling through colission objects
@@ -283,18 +408,17 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
if (force > clmd->sim_parms->max_sewing) {
force = clmd->sim_parms->max_sewing;
}
- mul_fvector_S(stretch_force, dir, force);
+ mul_v3_v3fl(stretch_force, dir, force);
}
else {
- mul_fvector_S(stretch_force, dir, k * (length - L));
+ mul_v3_v3fl(stretch_force, dir, k * (length - L));
}
-
- VECADD(s->f, s->f, stretch_force);
-
+
+ add_v3_v3(s->f, stretch_force);
+
// Ascher & Boxman, p.21: Damping only during elonglation
// something wrong with it...
- mul_fvector_S(damping_force, dir, clmd->sim_parms->Cdis * dot_v3v3(vel, dir));
- VECADD(s->f, s->f, damping_force);
+ madd_v3_v3fl(s->f, dir, clmd->sim_parms->Cdis * dot_v3v3(vel, dir));
/* VERIFIED */
dfdx_spring(s->dfdx, dir, length, L, k);
@@ -304,17 +428,15 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
}
}
- else
-#endif
- if (s->type & CLOTH_SPRING_TYPE_GOAL) {
+ else if (s->type & CLOTH_SPRING_TYPE_GOAL) {
float target[3];
s->flags |= CLOTH_SPRING_FLAG_NEEDED;
// current_position = xold + t * (xnew - xold)
- interp_v3_v3v3(target, verts[s->ij].xold, verts[s->ij].xconst, time);
+ interp_v3_v3v3(target, v1->xold, v1->xconst, time);
sub_v3_v3v3(extent, lVector_v3(X, s->ij), target);
- BKE_sim_debug_data_add_line(clmd->debug_data, verts[s->ij].xconst, verts[s->ij].xold, 1,0,0, "springs", hash_vertex(7825, s->ij));
+ BKE_sim_debug_data_add_line(clmd->debug_data, v1->xconst, v1->xold, 1,0,0, "springs", hash_vertex(7825, s->ij));
// SEE MSG BELOW (these are UNUSED)
// dot = dot_v3v3(extent, extent);
@@ -323,7 +445,7 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
k = clmd->sim_parms->goalspring;
scaling = k + s->stiffness * fabsf(clmd->sim_parms->max_struct - k);
- k = verts[s->ij].goal * scaling / (clmd->sim_parms->avg_spring_len + FLT_EPSILON);
+ k = v1->goal * scaling / (clmd->sim_parms->avg_spring_len + FLT_EPSILON);
madd_v3_v3fl(s->f, extent, -k);
/* XXX this has no effect: dir is always null at this point! - lukas_t
@@ -355,27 +477,23 @@ static void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s, con
static void cloth_apply_spring_force(ClothModifierData *clmd, ClothSpring *s, lVector &F, lMatrix &dFdX, lMatrix &dFdV)
{
- TripletList trips;
-// lMatrix tmp(F.rows(), F.rows());
-
- if (s->flags & CLOTH_SPRING_FLAG_NEEDED) {
-// if (!(s->type & CLOTH_SPRING_TYPE_BENDING)) {
-// triplets_m3(trips, s
@@ Diff output truncated at 10240 characters. @@
More information about the Bf-blender-cvs
mailing list