#include "mgraph.h"
#include "parallel.h"
-double vertex_areas[N], vertex_mean_edge_lengths[N], edge_lengths[N][V6];
+double vertex_mean_edge_lengths[N];
+
+static double vertex_areas[N];
+static double edge_lengths[N][V6];
+static double rim_vertex_angles[N];
static double best_energy= DBL_MAX;
static PreComputation *const precomps[]= {
compute_edge_lengths,
- compute_vertex_areas
+ compute_vertex_areas,
+ compute_rim_twist_angles
};
static const CostContribution costs[]= {
#if XBITS==3
#define STOP_EPSILON 1e-6
- COST( 3e3, line_bending_cost)
- COST( 3e3, edge_length_variation_cost)
+ COST( 3e3, vertex_displacement_cost)
COST( 0.4e3, rim_proximity_cost)
- COST( 1e6, edge_angle_cost)
- #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.5/1.7)
-// COST( 1e1, small_triangles_cost)
+ COST( 1e7, edge_angle_cost)
+ #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.2/1.7)
+ COST( 1e2, small_triangles_cost)
COST( 1e12, noncircular_rim_cost)
#endif
#if XBITS==4
-#define STOP_EPSILON 1.2e-4
- COST( 3e5, line_bending_cost)
- COST( 10e3, edge_length_variation_cost)
- COST( 9.0e3, rim_proximity_cost) // 5e1 is too much
- // 2.5e1 is too little
- // 0.2e1 grows compared to previous ?
- // 0.6e0 shrinks compared to previous ?
+#define STOP_EPSILON 5e-3
+ COST( 3e4, vertex_displacement_cost) // NB this is probably wrong now
+ COST( 3e4, vertex_edgewise_displ_cost) // we have changed the power
+ COST( 2e2, rim_proximity_cost)
+ COST( 1e4, rim_twist_cost)
+ COST( 1e12, noncircular_rim_cost)
+ COST( 10e1, nonequilateral_triangles_cost)
+// COST( 1e1, small_triangles_cost)
+// COST( 1e6, edge_angle_cost)
+ #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.5/1.7)
+#endif
-// COST( 1e12, edge_angle_cost)
- #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.5/1.3)
- COST( 1e18, noncircular_rim_cost)
+#if XBITS==5
+#define STOP_EPSILON 7e-4
+ COST( 3e4, vertex_displacement_cost)
+ COST( 3e4, vertex_edgewise_displ_cost)
+ COST( 2e-1, rim_proximity_cost)
+ COST( 3e3, rim_twist_cost)
+ COST( 1e12, noncircular_rim_cost)
+ COST( 3e2, nonequilateral_triangles_cost)
+// COST( 1e1, small_triangles_cost)
+// COST( 1e6, edge_angle_cost)
+ #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.5/1.7)
#endif
-#if XBITS>=5 /* nonsense follows but never mind */
+#if XBITS==6
+#define STOP_EPSILON 1.2e-4
+ COST( 3e4, vertex_displacement_cost)
+ COST( 3e4, vertex_edgewise_displ_cost)
+ COST( 2e-1, rim_proximity_cost)
+ COST( 1e3, rim_twist_cost)
+ COST( 1e12, noncircular_rim_cost)
+ COST( 10e1, nonequilateral_triangles_cost)
+// COST( 1e1, small_triangles_cost)
+// COST( 1e6, edge_angle_cost)
+ #define EDGE_ANGLE_COST_CIRCCIRCRAT (0.5/1.7)
+#endif
+
+#if XBITS>=7 /* nonsense follows but never mind */
#define STOP_EPSILON 1e-6
COST( 3e5, line_bending_cost)
COST( 10e2, edge_length_variation_cost)
static void addcost(double *energy, double tweight, double tcost, int pr) {
double tenergy= tweight * tcost;
- if (pr) printf(" %# e x %g > %# e* |", tcost, tweight, tenergy);
+ if (pr) printf(/*" %# e >"*/ " %# e* |", /*tcost,*/ tenergy);
*energy += tenergy;
}
}
}
-/*---------- Edgewise vertex displacement ----------*/
+/*---------- displacement of vertices across a midpoint ----------*/
+
+ /*
+ * Subroutine used where we have
+ *
+ * R - - - - - - - M . - - - - R'
+ * ` .
+ * ` .
+ * S
+ *
+ * and wish to say that the vector RM should be similar to MS
+ * or to put it another way S = M + RM
+ *
+ * NB this is not symmetric wrt R and S since it divides by
+ * |SM| but not |RM| so you probably want to call it twice.
+ *
+ * Details:
+ *
+ * Let R' = M + SM
+ * D = R' - R
+ *
+ * Then the (1/delta)th power of the cost is
+ * proportional to |D|, and
+ * inversely proportional to |SM|
+ * except that |D| is measured in a wierd way which counts
+ * distance in the same direction as SM 1/lambda times as much
+ * ie the equipotential surfaces are ellipsoids around R',
+ * lengthened by lambda in the direction of RM.
+ *
+ * So
+ * delta
+ * [ -1 ]
+ * cost = [ lambda . ( D . SM/|SM| ) + | D x SM/|SM| | ]
+ * R,S,M [ ------------------------------------------- ]
+ * [ |SM| ]
+ *
+ */
+
+static double vertex_one_displ_cost(const double r[D3], const double s[D3],
+ const double midpoint[D3],
+ double delta, double inv_lambda) {
+ const double smlen2_epsilon= 1e-12;
+ double sm[D3], d[D3], ddot, dcross[D3];
+ int k;
+
+ K sm[k]= -s[k] + midpoint[k];
+ K d[k]= midpoint[k] + sm[k] - r[k];
+ ddot= dotprod(d,sm);
+ xprod(dcross, d,sm);
+ double smlen2= magnD2(sm);
+ double cost_basis= inv_lambda * ddot + magnD(dcross);
+ double cost= pow(cost_basis / (smlen2 + smlen2_epsilon), delta);
+
+ return cost;
+}
+
+/*---------- displacement of vertices opposite at a vertex ----------*/
+
+ /*
+ * At vertex Q considering edge direction e to R
+ * and corresponding opposite edge to S.
+ *
+ * This is vertex displacement as above with M=Q
+ */
+
+double vertex_displacement_cost(const Vertices vertices, int section) {
+ const double inv_lambda= 1.0/1; //2;
+ const double delta= 6;
+
+ int si,e,qi,ri;
+ double total_cost= 0;
+
+ FOR_EDGE(qi,e,ri, OUTER) {
+ si= EDGE_END2(qi,(e+3)%V6); if (si<0) continue;
+
+ total_cost += vertex_one_displ_cost(vertices[ri], vertices[si], vertices[qi],
+ delta, inv_lambda);
+ }
+ return total_cost;
+}
+
+/*---------- displacement of vertices opposite at an edge ----------*/
+
+ /*
+ * At edge PQ considering vertices R and S (see diagram
+ * below for overly sharp edge cost).
+ *
+ * Let M = midpoint of PQ
+ */
+
+double vertex_edgewise_displ_cost(const Vertices vertices, int section) {
+ const double inv_lambda= 1.0/1; //2;
+ const double delta= 6;
+
+ int pi,e,qi,ri,si, k;
+ double m[D3];
+ double total_cost= 0;
+
+ FOR_EDGE(pi,e,qi, OUTER) {
+ si= EDGE_END2(pi,(e+V6-1)%V6); if (si<0) continue;
+ ri= EDGE_END2(pi,(e +1)%V6); if (ri<0) continue;
+
+ K m[k]= 0.5 * (vertices[pi][k] + vertices[qi][k]);
+
+ total_cost += vertex_one_displ_cost(vertices[ri], vertices[si], m,
+ delta, inv_lambda);
+ }
+ return total_cost;
+}
+
+
+/*---------- at-vertex edge angles ----------*/
/*
* Definition:
return cost;
}
+/*---------- proportional edge length variation ----------*/
+
+ /*
+ * Definition:
+ *
+ * See the diagram above.
+ * r
+ * cost = ( |PQ| - |QR| )
+ * Q,e
+ */
+
+double prop_edge_length_variation_cost(const Vertices vertices, int section) {
+ const double num_epsilon= 1e-6;
+
+ double cost= 0, exponent_r= 2;
+ int q, e,r, eback;
+
+ FOR_EDGE(q,e,r, OUTER) {
+ eback= edge_reverse(q,e);
+ double le= edge_lengths[q][e];
+ double leback= edge_lengths[q][eback];
+ double diff= le - leback;
+ double num= MIN(le, leback);
+ cost += pow(diff / (num + num_epsilon), exponent_r);
+ }
+ return cost;
+}
+
/*---------- rim proximity cost ----------*/
static void find_nearest_oncircle(double oncircle[D3], const double p[D3]) {
}
double rim_proximity_cost(const Vertices vertices, int section) {
- double oncircle[3], cost=0;
+ double oncircle[D3], cost=0;
int v;
FOR_VERTEX(v, OUTER) {
return cost;
}
+/*---------- rim contact angle rotation ----------*/
+
+void compute_rim_twist_angles(const Vertices vertices, int section) {
+ double oncircle[D3], distance[D3];
+ int vpy,vpx,v,k;
+
+ FOR_NEAR_RIM_VERTEX(vpy,vpx,v, 1,OUTER) {
+ find_nearest_oncircle(oncircle, vertices[v]);
+ /* we are interested in the angle subtended at the rim, from the
+ * rim's point of view. */
+ K distance[k]= vertices[v][k] - oncircle[k];
+ double distance_positive_z= distance[2];
+ double distance_radial_outwards= dotprod(distance, oncircle);
+ rim_vertex_angles[v]= atan2(distance_positive_z, distance_radial_outwards);
+ }
+}
+
+double rim_twist_cost(const Vertices vertices, int section) {
+ double total_cost= 0;
+ int vpy,vpx,v0,v1;
+
+ FOR_NEAR_RIM_VERTEX(vpy,vpx,v0, 1,OUTER) {
+ v1= EDGE_END2(v0,0); assert(v1!=0);
+ double delta= rim_vertex_angles[v0] - rim_vertex_angles[v1];
+ if (delta < M_PI) delta += 2*M_PI;
+ if (delta > M_PI) delta -= 2*M_PI;
+
+ double cost= pow(delta, 4);
+ total_cost += cost;
+ }
+
+ return total_cost;
+}
+
/*---------- overly sharp edge cost ----------*/
/*
/*---------- small triangles cost ----------*/
/*
+ * Consider a triangle PQS
*
- * Q `-_
- * / | `-_
- * / | `-.
- * / | S
- * / | _,-'
- * / | _,-'
- * / , P '
- * / ,-'
- * /,-'
- * /'
- * R
- *
- * Let delta = angle between two triangles' normals
- *
- * Giving energy contribution:
- *
- * 2
- * E = F . delta
- * vd, edge PQ vd
+ * Cost is 1/( area^2 )
*/
double small_triangles_cost(const Vertices vertices, int section) {
return total_cost;
}
+
+/*---------- nonequilateral triangles cost ----------*/
+
+ /*
+ * Consider a triangle PQR
+ *
+ * let edge lengths a=|PQ| b=|QR| c=|RP|
+ *
+ * predicted edge length p = 1/3 * (a+b+c)
+ *
+ * compute cost for each x in {a,b,c}
+ *
+ *
+ * cost = (x-p)^2 / p^2
+ * PQR,x
+ */
+
+double nonequilateral_triangles_cost(const Vertices vertices, int section) {
+ double pr[D3], abc[3];
+ int pi,e0,e1,qi,ri, k,i;
+ double our_epsilon=1e-6;
+ double total_cost= 0;
+
+ FOR_EDGE(pi,e0,qi, OUTER) {
+ e1= (e0+V6-1)%V6;
+ ri= EDGE_END2(pi,e1); if (ri<0) continue;
+
+ K pr[k]= -vertices[pi][k] + vertices[ri][k];
+
+ abc[0]= edge_lengths[pi][e0]; /* PQ */
+ abc[1]= edge_lengths[qi][e1]; /* QR */
+ abc[2]= magnD(pr);
+
+ double p= (1/3.0) * (abc[0]+abc[1]+abc[2]);
+ double p_inv2= 1/(p*p + our_epsilon);
+
+ for (i=0; i<3; i++) {
+ double diff= (abc[i] - p);
+ double cost= diff*diff * p_inv2;
+ total_cost += cost;
+ }
+ }
+
+ return total_cost;
+}
~ian / moebius2.git / blobdiff