/* Actually move the fish. */
void
move_fish(fish_t* fish, const int n_fish, const double dt)
{
int i;
for (i = 0; i < n_fish; ++i) {
fish[i].x += dt * fish[i].vx;
fish[i].y += dt * fish[i].vy;
fish[i].vx += dt * fish[i].ax;
fish[i].vy += dt * fish[i].ay;
bounce_fish(&fish[i]);
assert(scale_coord(fish[i].x) >= 0.0);
assert(scale_coord(fish[i].y) >= 0.0);
}
}
/*
Dump out all the fishies (and their center of gravity)
in a format that the viewer understands.
*/
void
output_fish(FILE* output_fp, const double t, const double dt,
const fish_t* fish, const int n_fish)
{
int i;
double cg_x = 0.0;
double cg_y = 0.0;
fprintf(output_fp, "%.5g (%.5g):\n", t, dt);
for (i = 0; i < n_fish; ++i) {
cg_x += fish[i].x;
cg_y += fish[i].y;
fprintf(output_fp, " %d: (%g, %g)\n", i,
scale_coord(fish[i].x), scale_coord(fish[i].y));
}
cg_x /= n_fish;
cg_y /= n_fish;
fprintf(output_fp, " cg: (%g, %g)\n", scale_coord(cg_x),
scale_coord(cg_y));
}
real overlap_scaling(int dim, int m, real *x, real *width, real scale_sta, real scale_sto, real epsilon, int maxiter){
/* do a bisection between scale_sta and scale_sto, up to maxiter iterations or till interval <= epsilon, to find the best scaling to avoid overlap
m: number of points
x: the coordinates
width: label size
scale_sta: starting bracket. If <= 0, assumed 0. If > 0, we will test this first and if no overlap, return.
scale_sto: stopping bracket. This must be overlap free if positive. If <= 0, we will find automatically by doubling from scale_sta, or epsilon if scale_sta <= 0.
typically usage:
- for shrinking down a layout to reduce white space, we will assume scale_sta and scale_sto are both given and positive, and scale_sta is the current guess.
- for scaling up, we assume scale_sta, scale_sto <= 0
*/
real scale = -1, scale_best = -1;
SparseMatrix C = NULL;
int check_overlap_only = 1;
int overlap = 0;
real two = 2;
int iter = 0;
assert(epsilon > 0);
if (scale_sta <= 0) {
scale_sta = 0;
} else {
scale_coord(dim, m, x, scale_sta);
C = get_overlap_graph(dim, m, x, width, check_overlap_only);
if (!C || C->nz == 0) {
if (Verbose) fprintf(stderr," shrinking with with %f works\n", scale_sta);
SparseMatrix_delete(C);
return scale_sta;
}
scale_coord(dim, m, x, 1./scale_sta);
SparseMatrix_delete(C);
}
if (scale_sto < 0){
if (scale_sta == 0) {
scale_sto = epsilon;
} else {
scale_sto = scale_sta;
}
scale_coord(dim, m, x, scale_sto);
do {
scale_sto *= two;
scale_coord(dim, m, x, two);
C = get_overlap_graph(dim, m, x, width, check_overlap_only);
overlap = (C && C->nz > 0);
SparseMatrix_delete(C);
} while (overlap);
scale_coord(dim, m, x, 1/scale_sto);/* unscale */
}
scale_best = scale_sto;
while (iter++ < maxiter && scale_sto - scale_sta > epsilon){
fprintf(stderr,"in overlap_scaling iter=%d, maxiter=%d, scaling bracket: {%f,%f}\n", iter, maxiter, scale_sta, scale_sto);
scale = 0.5*(scale_sta + scale_sto);
scale_coord(dim, m, x, scale);
C = get_overlap_graph(dim, m, x, width, check_overlap_only);
scale_coord(dim, m, x, 1./scale);/* unscale */
overlap = (C && C->nz > 0);
SparseMatrix_delete(C);
if (overlap){
scale_sta = scale;
} else {
scale_best = scale_sto = scale;
}
}
/* final scaling */
scale_coord(dim, m, x, scale_best);
return scale_best;
}
