/* computes current energy */
int Match::BVZ_ComputeEnergy()
{
int k;
Coord p, d, q, dq;
E = 0;
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
E += BVZ_data_penalty(p, d);
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if (q>=Coord(0,0) && q<im_size)
{
dq = Coord(IMREF(x_left, q), IMREF(y_left, q));
E += BVZ_smoothness_penalty(p, q, d, dq);
}
}
}
return E;
}
int Match::data_penalty_GRAY(Coord l, Coord r)
{
int d;
d = IMREF(im_left, l) - IMREF(im_right, r);
if (params.data_cost==Parameters::L1) { if (d<0) d = -d; } else d = d*d;
if (d>CUTOFF) d = CUTOFF;
return d;
}
int Match::smoothness_penalty2_GRAY(Coord p, Coord np, Coord disp)
{
int dl, dr;
dl = IMREF(segm_left, p) - IMREF(segm_left, np);
dr = IMREF(segm_right, p+disp) - IMREF(segm_right, np+disp);
if (dl<0) dl = -dl; if (dr<0) dr = -dr;
if (dl<params.I_threshold2 && dr<params.I_threshold2) return params.lambda1;
else return params.lambda2;
}
int Match::smoothness_penalty_right_GRAY(Coord p, Coord np, Coord disp, Coord ndisp)
{
int d;
if (disp == ndisp) return 0;
d = IMREF(segm_right, p) - IMREF(segm_right, np);
if (d<0) d = -d;
if (d<params.I_threshold) return params.lambda1;
else return params.lambda2;
}
void PortraitCut::saveComp(char* name) {
RGBImage im = (RGBImage) imNew(IMAGE_RGB, _w, _h);
int i, j,index=0;
for (j=0; j<_h; j++)
for (i=0; i<_w; i++, ++index) {
Coord p(i,j);
unsigned char* cref = _imptr(_labels[index], p);
IMREF(im,p).r = cref[0];
IMREF(im,p).g = cref[1];
IMREF(im,p).b = cref[2];
}
int res = imSave(im,name);
assert(res==0);
imFree(im);
}
int Match::smoothness_penalty_right_GRAY(Coord p, Coord np, Coord disp, Coord ndisp)
{
int d, R;
if (disp == ndisp) return 0;
if (disp.x == OCCLUDED || ndisp.x == OCCLUDED) R = params.interaction_radius;
else
{
int Rx = disp.x - ndisp.x; if (Rx < 0) Rx = -Rx;
int Ry = disp.y - ndisp.y; if (Ry < 0) Ry = -Ry;
R = Rx + Ry;
if (R > params.interaction_radius) R = params.interaction_radius;
}
d = IMREF(segm_right, p) - IMREF(segm_right, np);
if (d<0) d = -d;
if (d<params.I_threshold) return R*params.lambda1;
else return R*params.lambda2;
}
int Match::smoothness_penalty_right_COLOR(Coord p, Coord np, Coord disp, Coord ndisp)
{
int d, d_max, R;
if (disp == ndisp) return 0;
if (disp.x == OCCLUDED || ndisp.x == OCCLUDED) R = params.interaction_radius;
else
{
int Rx = disp.x - ndisp.x; if (Rx < 0) Rx = -Rx;
int Ry = disp.y - ndisp.y; if (Ry < 0) Ry = -Ry;
R = Rx + Ry;
if (R > params.interaction_radius) R = params.interaction_radius;
}
d_max = 0;
/* red component */
d = IMREF(segm_color_right, p).r - IMREF(segm_color_right, np).r;
if (d<0) d = -d; if (d_max<d) d_max = d;
/* green component */
d = IMREF(segm_color_right, p).g - IMREF(segm_color_right, np).g;
if (d<0) d = -d; if (d_max<d) d_max = d;
/* blue component */
d = IMREF(segm_color_right, p).b - IMREF(segm_color_right, np).b;
if (d<0) d = -d; if (d_max<d) d_max = d;
if (d_max<params.I_threshold) return R*params.lambda1;
else return R*params.lambda2;
}
void PortraitCut::saveLabels(const char* name) {
fprintf(_fp, "Trying to save file %s\n",name); fflush(_fp);
GrayImage im = (GrayImage) imNew(IMAGE_GRAY, _w, _h);
int i, j,index=0;
for (j=0; j<_h; j++)
for (i=0; i<_w; i++, ++index) {
Coord p(i,j);
IMREF(im,p) = (unsigned char) _labels[index];
}
imSave(im,name);
imFree(im);
}
int Match::data_penalty_SUBPIXEL_GRAY(Coord l, Coord r)
{
int dl, dr, d;
int Il, Il_min, Il_max, Ir, Ir_min, Ir_max;
Il = IMREF(im_left, l); Ir = IMREF(im_right, r);
Il_min = IMREF(im_left_min, l); Ir_min = IMREF(im_right_min, r);
Il_max = IMREF(im_left_max, l); Ir_max = IMREF(im_right_max, r);
if (Il < Ir_min) dl = Ir_min - Il;
else if (Il > Ir_max) dl = Il - Ir_max;
else return 0;
if (Ir < Il_min) dr = Il_min - Ir;
else if (Ir > Il_max) dr = Ir - Il_max;
else return 0;
d = MIN(dl, dr); if (params.data_cost==Parameters::L2) d = d*d;
if (d>CUTOFF) d = CUTOFF;
return d;
}
int Match::smoothness_penalty_right_COLOR(Coord p, Coord np, Coord disp, Coord ndisp)
{
int d, d_max;
if (disp == ndisp) return 0;
d_max = 0;
/* red component */
d = IMREF(segm_color_right, p).r - IMREF(segm_color_right, np).r;
if (d<0) d = -d; if (d_max<d) d_max = d;
/* green component */
d = IMREF(segm_color_right, p).g - IMREF(segm_color_right, np).g;
if (d<0) d = -d; if (d_max<d) d_max = d;
/* blue component */
d = IMREF(segm_color_right, p).b - IMREF(segm_color_right, np).b;
if (d<0) d = -d; if (d_max<d) d_max = d;
if (d_max<params.I_threshold) return params.lambda1;
else return params.lambda2;
}
int Match::data_penalty_COLOR(Coord l, Coord r)
{
int d, d_sum = 0;
/* red component */
d = IMREF(im_color_left, l).r - IMREF(im_color_right, r).r;
if (params.data_cost==Parameters::L1) { if (d<0) d = -d; } else d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
/* green component */
d = IMREF(im_color_left, l).g - IMREF(im_color_right, r).g;
if (params.data_cost==Parameters::L1) { if (d<0) d = -d; } else d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
/* blue component */
d = IMREF(im_color_left, l).b - IMREF(im_color_right, r).b;
if (params.data_cost==Parameters::L1) { if (d<0) d = -d; } else d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
return d_sum/3;
}
int Match::data_penalty_SUBPIXEL_COLOR(Coord l, Coord r)
{
int dl, dr, d, d_sum = 0;
int Il, Il_min, Il_max, Ir, Ir_min, Ir_max;
/* red component */
Il = IMREF(im_color_left, l).r; Ir = IMREF(im_color_right, r).r;
Il_min = IMREF(im_color_left_min, l).r; Ir_min = IMREF(im_color_right_min, r).r;
Il_max = IMREF(im_color_left_max, l).r; Ir_max = IMREF(im_color_right_max, r).r;
if (Il < Ir_min) dl = Ir_min - Il;
else if (Il > Ir_max) dl = Il - Ir_max;
else dl = 0;
if (Ir < Il_min) dr = Il_min - Ir;
else if (Ir > Il_max) dr = Ir - Il_max;
else dr = 0;
d = MIN(dl, dr); if (params.data_cost==Parameters::L2) d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
/* green component */
Il = IMREF(im_color_left, l).g; Ir = IMREF(im_color_right, r).g;
Il_min = IMREF(im_color_left_min, l).g; Ir_min = IMREF(im_color_right_min, r).g;
Il_max = IMREF(im_color_left_max, l).g; Ir_max = IMREF(im_color_right_max, r).g;
if (Il < Ir_min) dl = Ir_min - Il;
else if (Il > Ir_max) dl = Il - Ir_max;
else dl = 0;
if (Ir < Il_min) dr = Il_min - Ir;
else if (Ir > Il_max) dr = Ir - Il_max;
else dr = 0;
d = MIN(dl, dr); if (params.data_cost==Parameters::L2) d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
/* blue component */
Il = IMREF(im_color_left, l).b; Ir = IMREF(im_color_right, r).b;
Il_min = IMREF(im_color_left_min, l).b; Ir_min = IMREF(im_color_right_min, r).b;
Il_max = IMREF(im_color_left_max, l).b; Ir_max = IMREF(im_color_right_max, r).b;
if (Il < Ir_min) dl = Ir_min - Il;
else if (Il > Ir_max) dl = Il - Ir_max;
else dl = 0;
if (Ir < Il_min) dr = Il_min - Ir;
else if (Ir > Il_max) dr = Ir - Il_max;
else dr = 0;
d = MIN(dl, dr); if (params.data_cost==Parameters::L2) d = d*d;
if (d>CUTOFF) d = CUTOFF;
d_sum += d;
return d_sum/3;
}
void Match::BVZ_Expand(Coord a)
{
Coord p, d, q, dq;
Energy::Var var, qvar;
int E_old, E00, E0a, Ea0;
int k;
/* node_vars stores variables corresponding to nodes */
Energy *e = new Energy(BVZ_error_function);
/* initializing */
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
if (a == d)
{
IMREF(node_vars, p) = VAR_ACTIVE;
e -> add_constant(BVZ_data_penalty(p, d));
}
else
{
IMREF(node_vars, p) = var = e -> add_variable();
e -> ADD_TERM1(var, BVZ_data_penalty(p, d), BVZ_data_penalty(p, a));
}
}
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
var = (Energy::Var) IMREF(node_vars, p);
/* smoothness term */
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if ( ! ( q>=Coord(0,0) && q<im_size ) ) continue;
qvar = (Energy::Var) IMREF(node_vars, q);
dq = Coord(IMREF(x_left, q), IMREF(y_left, q));
if (var != VAR_ACTIVE && qvar != VAR_ACTIVE)
E00 = BVZ_smoothness_penalty(p, q, d, dq);
if (var != VAR_ACTIVE)
E0a = BVZ_smoothness_penalty(p, q, d, a);
if (qvar != VAR_ACTIVE)
Ea0 = BVZ_smoothness_penalty(p, q, a, dq);
if (var != VAR_ACTIVE)
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM2(var, qvar, E00, E0a, Ea0, 0);
else e -> ADD_TERM1(var, E0a, 0);
}
else
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM1(qvar, Ea0, 0);
else {}
}
}
}
E_old = E;
E = e -> minimize();
if (E < E_old)
{
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
var = (Energy::Var) IMREF(node_vars, p);
if (var!=VAR_ACTIVE && e->get_var(var)==VALUE1)
{
IMREF(x_left, p) = a.x; IMREF(y_left, p) = a.y;
}
}
}
delete e;
}
double PortraitCut::BVZ_Expand(ushort a, double E_old) {
Coord p, np;
ushort l, nl;
Graph *g;
float delta, P_00, P_0a, P_a0;
Graph::node_id index, nindex;
int k, ind=0;
double E;
/* indeces_a stores node indeces */
/* D_a sto res penalties for assigning label a */
g = new Graph(BVZ_error_function);
/* initializing */
E = 0.;
for (p.y=0; p.y<_h; p.y++)
for (p.x=0; p.x<_w; p.x++, ++ind)
{
l = _labels[ind];
if (a == l) // 和原始的label一样
{
IMREF(indeces_a, p) = INDEX_ACTIVE; //返回点p在graph中的节点索引，默认为0
E += BVZ_data_penalty(p, l);
continue;
}
// 而void *则不同，任何类型的指针都可以直接赋值给它，无需进行强制类型转换：//void *p1; //int *p2; // p1 = p2
//label 不一样的话
IMREF(indeces_a, p) = g -> add_node();
delta = BVZ_data_penalty(p, l);
IMREF(D_a, p) = BVZ_data_penalty(p, a) - delta;
E += delta;
}
ind=0;
for (p.y=0; p.y<_h; p.y++)
for (p.x=0; p.x<_w; p.x++, ++ind)
{
l = _labels[ind];
index = (Graph::node_id) IMREF(indeces_a, p);
/* adding interactions */
for (k=0; k<(int)NEIGHBOR_NUM; k++)
{
np = p + NEIGHBORS[k];
if ( ! ( np>=Coord(0,0) && np<_size ) ) continue; //HUM
nl = _labels[CINDEX(np)];
nindex = (Graph::node_id) IMREF(indeces_a, np);//获取在graph 中node的id
if (IS_NODE_ID(index))
{
if (IS_NODE_ID(nindex))
{
P_00 = BVZ_interaction_penalty(p, np, l, nl);
P_0a = BVZ_interaction_penalty(p, np, l, a);
P_a0 = BVZ_interaction_penalty(p, np, a, nl);
delta = (P_00 < P_0a) ? P_00 : P_0a;
if (delta > 0)
{
IMREF(D_a, p) -= delta; E += delta;
P_00 -= delta;
P_0a -= delta;
}
delta = (P_00 < P_a0) ? P_00 : P_a0;
if (delta > 0)
{
IMREF(D_a, np) -= delta; E += delta;
P_00 -= delta;
P_a0 -= delta;
}
if (P_00 > 0.0001) { fprintf(_fp, "ERROR: BVZ_interaction_penalty() is non-metric %f!\n",P_00); fflush(_fp); /*assert(0);*/ }
#ifdef BVZ_ALPHA_SINK
g -> add_edge(index, nindex, P_0a, P_a0);
#else
g -> add_edge(index, nindex, P_a0, P_0a);
#endif
}
else
{
delta = BVZ_interaction_penalty(p, np, l, a);
IMREF(D_a, p) -= delta; E += delta;
}
}
else
{
if (IS_NODE_ID(nindex))
{
delta = BVZ_interaction_penalty(p, np, a, nl);
IMREF(D_a, np) -= delta; E += delta;
}
}
}// end for neighbor
}// end for image-pixel
/* adding source and sink edges */
for (p.y=0; p.y<_h; p.y++)
for (p.x=0; p.x<_w; p.x++)
{
index = (Graph::node_id) IMREF(indeces_a, p);
if (IS_NODE_ID(index))
{
delta = (float) IMREF(D_a, p);
#ifdef BVZ_ALPHA_SINK
if (delta > 0) { g -> set_tweights(index, delta, 0); }
else { g -> set_tweights(index, 0, -delta); E += delta; }
#else
if (delta > 0) { g -> set_tweights(index, 0, delta); }
else { g -> set_tweights(index, -delta, 0); E += delta; }
#endif
}
}
E += g -> maxflow();
//fprintf(_fp, "internal E: %f\n",E); fflush(_fp);
if (E < E_old)
{
//fprintf(_fp,"Writing into _labels\n"); fflush(_fp);
ind=0;
for (p.y=0; p.y<_h; p.y++)
for (p.x=0; p.x<_w; p.x++, ++ind)
{
index = (Graph::node_id) IMREF(indeces_a, p);
if (IS_NODE_ID(index) && g->what_segment(index)==BVZ_TERM_B)
{
_labels[ind] = a; //进行交换操作
}
}
delete g;
return E;
}
delete g;
return E_old;
}
/* computes current energy */
int Match::KZ1_ComputeEnergy()
{
int k;
Coord p, d, q, dq;
E = 0;
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
/* left image and data penalty */
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
if (d.x == OCCLUDED) E += KZ1_OCCLUSION_PENALTY;
else
{
q = p + d;
if (q>=Coord(0,0) && q<im_size)
{
dq = Coord(IMREF(x_right, q), IMREF(y_right, q));
if (d == -dq)
{
E += KZ1_data_penalty(p, q);
}
#ifndef NDEBUG
/* check visibility constaint */
if (dq.x != OCCLUDED && is_blocked(-dq, d))
{
fprintf(stderr, "KZ1: Visibility constraint is violated!\n");
exit(1);
}
#endif
}
}
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if (q>=Coord(0,0) && q<im_size)
{
dq = Coord(IMREF(x_left, q), IMREF(y_left, q));
E += KZ1_smoothness_penalty_left(p, q, d, dq);
}
}
/* right image */
d = Coord(IMREF(x_right, p), IMREF(y_right, p));
if (d.x == OCCLUDED) E += KZ1_OCCLUSION_PENALTY;
#ifndef NDEBUG
else
{
/* check visibility constaint */
q = p + d;
if (q>=Coord(0,0) && q<im_size)
{
dq = Coord(IMREF(x_left, q), IMREF(y_left, q));
if (dq.x != OCCLUDED && is_blocked(dq, -d))
{
fprintf(stderr, "KZ1: Visibility constraint is violated!\n");
exit(1);
}
}
}
#endif
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if (q>=Coord(0,0) && q<im_size)
{
dq = Coord(IMREF(x_right, q), IMREF(y_right, q));
E += KZ1_smoothness_penalty_right(p, q, d, dq);
}
}
}
return E;
}
/* computes the minimum a-expansion configuration */
void Match::KZ1_Expand(Coord a)
{
Coord p, q, d, dq;
Energy::Var var, qvar;
int E_old, delta, E00, E0a, Ea0, Eaa;
int k;
Energy *e = new Energy(KZ1_error_function);
/* initializing */
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
if (a == d) IMREF(node_vars_left, p) = VAR_ACTIVE;
else
{
IMREF(node_vars_left, p) = var = e -> add_variable();
if (d.x == OCCLUDED) e -> ADD_TERM1(var, KZ1_OCCLUSION_PENALTY, 0);
}
d = Coord(IMREF(x_right, p), IMREF(y_right, p));
if (a == -d) IMREF(node_vars_right, p) = VAR_ACTIVE;
else
{
IMREF(node_vars_right, p) = var = e -> add_variable();
if (d.x == OCCLUDED) e -> ADD_TERM1(var, KZ1_OCCLUSION_PENALTY, 0);
}
}
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
/* data and visibility terms */
d = Coord(IMREF(x_left, p), IMREF(y_left, p));
var = (Energy::Var) IMREF(node_vars_left, p);
if (d != a && d.x != OCCLUDED)
{
q = p + d;
if (q>=Coord(0,0) && q<im_size)
{
qvar = (Energy::Var) IMREF(node_vars_right, q);
dq = Coord(IMREF(x_right, q), IMREF(y_right, q));
if (d == -dq)
{
delta = (is_blocked(a, d)) ? INFINITY : 0;
e -> ADD_TERM2(var, qvar, KZ1_data_penalty(p, q), delta, delta, 0);
}
else if (is_blocked(a, d))
{
e -> ADD_TERM2(var, qvar, 0, INFINITY, 0, 0);
}
}
}
q = p + a;
if (q>=Coord(0,0) && q<im_size)
{
qvar = (Energy::Var) IMREF(node_vars_right, q);
dq = Coord(IMREF(x_right, q), IMREF(y_right, q));
E0a = (is_blocked(d, a)) ? INFINITY : 0;
Ea0 = (is_blocked(-dq, a)) ? INFINITY : 0;
Eaa = KZ1_data_penalty(p, q);
if (var != VAR_ACTIVE)
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM2(var, qvar, 0, E0a, Ea0, Eaa);
else e -> ADD_TERM1(var, E0a, Eaa);
}
else
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM1(qvar, Ea0, Eaa);
else e -> add_constant(Eaa);
}
}
/* left smoothness term */
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if ( ! ( q>=Coord(0,0) && q<im_size ) ) continue;
qvar = (Energy::Var) IMREF(node_vars_left, q);
dq = Coord(IMREF(x_left, q), IMREF(y_left, q));
if (var != VAR_ACTIVE && qvar != VAR_ACTIVE)
E00 = KZ1_smoothness_penalty_left(p, q, d, dq);
if (var != VAR_ACTIVE)
E0a = KZ1_smoothness_penalty_left(p, q, d, a);
if (qvar != VAR_ACTIVE)
Ea0 = KZ1_smoothness_penalty_left(p, q, a, dq);
if (var != VAR_ACTIVE)
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM2(var, qvar, E00, E0a, Ea0, 0);
else e -> ADD_TERM1(var, E0a, 0);
}
else
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM1(qvar, Ea0, 0);
else {}
}
}
/* right smoothness term */
d = Coord(IMREF(x_right, p), IMREF(y_right, p));
var = (Energy::Var) IMREF(node_vars_right, p);
for (k=0; k<NEIGHBOR_NUM; k++)
{
q = p + NEIGHBORS[k];
if ( ! ( q>=Coord(0,0) && q<im_size ) ) continue;
qvar = (Energy::Var) IMREF(node_vars_right, q);
dq = Coord(IMREF(x_right, q), IMREF(y_right, q));
if (var != VAR_ACTIVE && qvar != VAR_ACTIVE)
E00 = KZ1_smoothness_penalty_right(p, q, d, dq);
if (var != VAR_ACTIVE)
E0a = KZ1_smoothness_penalty_right(p, q, d, -a);
if (qvar != VAR_ACTIVE)
Ea0 = KZ1_smoothness_penalty_right(p, q, -a, dq);
if (var != VAR_ACTIVE)
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM2(var, qvar, E00, E0a, Ea0, 0);
else e -> ADD_TERM1(var, E0a, 0);
}
else
{
if (qvar != VAR_ACTIVE) e -> ADD_TERM1(qvar, Ea0, 0);
else {}
}
}
/* visibility term */
if (d.x != OCCLUDED && is_blocked(a, -d))
{
q = p + d;
if (q>=Coord(0,0) && q<im_size)
{
if (d.x != -IMREF(x_left, q) || d.y != -IMREF(y_left, q))
e -> ADD_TERM2(var, (Energy::Var) IMREF(node_vars_left, q),
0, INFINITY, 0, 0);
}
}
}
E_old = E;
E = e -> minimize();
if (E < E_old)
{
for (p.y=0; p.y<im_size.y; p.y++)
for (p.x=0; p.x<im_size.x; p.x++)
{
var = (Energy::Var) IMREF(node_vars_left, p);
if (var != VAR_ACTIVE && e->get_var(var)==VALUE1)
{
IMREF(x_left, p) = a.x; IMREF(y_left, p) = a.y;
}
var = (Energy::Var) IMREF(node_vars_right, p);
if (var != VAR_ACTIVE && e->get_var(var)==VALUE1)
{
IMREF(x_right, p) = -a.x; IMREF(y_right, p) = -a.y;
}
}
}
delete e;
}
