int bseg_write_cellfile(BSEG * bseg, char *map_name)
{
int map_fd;
int row, nrows;
int col, ncols;
CELL *buffer;
CELL value;
map_fd = G_open_cell_new(map_name);
if (map_fd < 0) {
G_warning("%s(): unable to open new map layer [%s]", me, map_name);
return -1;
}
nrows = G_window_rows();
ncols = G_window_cols();
buffer = G_allocate_cell_buf();
for (row = 0; row < nrows; row++) {
for (col = 0; col < ncols; col++) {
bseg_get(bseg, &value, row, col);
buffer[col] = value;
}
if (G_put_raster_row(map_fd, buffer, CELL_TYPE) < 0) {
G_free(buffer);
G_unopen_cell(map_fd);
G_warning("%s(): unable to write new map layer [%s], row %d",
me, map_name, row);
return -2;
}
}
G_free(buffer);
G_close_cell(map_fd);
return 0;
}
int slope_length(int r, int c, int dr, int dc)
{
CELL top_alt, bot_alt, ridge;
char asp_value;
double res, top_ls, bot_ls;
WAT_ALT wa;
if (sides == 8) {
if (r == dr)
res = window.ns_res;
else if (c == dc)
res = window.ew_res;
else
res = diag;
}
else { /* sides == 4 */
bseg_get(&asp, &asp_value, dr, dc);
if (r == dr) {
if (asp_value == 2 || asp_value == 6)
res = window.ns_res;
else /* asp_value == 4, 8, -2, -4, -6, or -8 */
res = diag; /* how can res be diag with sides == 4??? */
}
else { /* c == dc */
if (asp_value == 4 || asp_value == 8)
res = window.ew_res;
else /* asp_value == 2, 6, -2, -4, -6, or -8 */
res = diag;
}
}
dseg_get(&s_l, &top_ls, r, c);
if (top_ls == half_res)
top_ls = res;
else
top_ls += res;
dseg_put(&s_l, &top_ls, r, c);
seg_get(&watalt, (char *) &wa, r, c);
top_alt = wa.ele;
seg_get(&watalt, (char *) &wa, dr, dc);
bot_alt = wa.ele;
if (top_alt > bot_alt) {
dseg_get(&s_l, &bot_ls, dr, dc);
if (top_ls > bot_ls) {
bot_ls = top_ls + res;
dseg_put(&s_l, &bot_ls, dr, dc);
cseg_get(&r_h, &ridge, r, c);
cseg_put(&r_h, &ridge, dr, dc);
}
}
return 0;
}
int find_con_slow(int r, int c, double *d1, double *d2, DCELL * con1,
DCELL * con2)
{
int ct, low_ct, node_ct;
int rr, cc, dor, doc;
double dd, shortest;
DCELL value;
char mask_value;
G_set_d_null_value(con1, 1);
G_set_d_null_value(con2, 1);
*d1 = *d2 = 1.0;
shortest = nrows * ncols;
for (rr = minr; rr <= maxr; rr++) {
for (cc = minc; cc <= maxc; cc++) {
/* FLAG_UNSET (seen, rr, cc); */
bseg_put(&bseen, &off, rr, cc);
}
}
minr = nrows;
minc = ncols;
maxr = maxc = -1;
/* set_seen_slow (r,c); */
bseg_put(&bseen, &on, r, c);
if (r < minr)
minr = r;
if (r > maxr)
maxr = r;
if (c < minc)
minc = c;
if (c > maxc)
maxc = c;
node_ct = 0;
zero = addpts_slow(zero, r, c, r, c, &node_ct);
low_ct = 0;
while (1) {
ct = low_ct++;
if (node_ct <= ct)
return 1;
rr = zero[ct].r;
cc = zero[ct].c;
dor = ABS(rr - r);
doc = ABS(cc - c);
bseg_get(&bmask, &mask_value, rr, cc);
if (!mask_value && rr >= 0 && cc >= 0 && rr < nrows && cc < ncols
&& zero[ct].d < shortest) {
dseg_get(&con, rr, cc, &value);
if (G_is_d_null_value(&value))
zero = addpts_slow(zero, r, c, rr, cc, &node_ct);
else if (G_is_d_null_value(con1)) {
*con1 = value;
*d1 = MIN(dor, doc) * 1.414 + ABS(dor - doc);
shortest = *d1 * 2.0 * i_val_l_f;
}
else if (*con1 == value) {
dd = MIN(dor, doc) * 1.414 + ABS(dor - doc);
if (dd < *d1) {
*d1 = dd;
shortest = dd * 2.0 * i_val_l_f;
}
}
else if (G_is_d_null_value(con2)) {
*con2 = value;
*d2 = MIN(dor, doc) * 1.414 + ABS(dor - doc);
shortest = *d2;
}
else {
dd = MIN(dor, doc) * 1.414 + ABS(dor - doc);
shortest = MIN(shortest, dd);
}
}
}
}
int do_cum(void)
{
int r, c, dr, dc;
char asp_val, asp_val_down;
char is_swale, this_flag_value, flag_value;
DCELL value, valued;
POINT point;
int killer, threshold;
int asp_r[9] = { 0, -1, -1, -1, 0, 1, 1, 1, 0 };
int asp_c[9] = { 0, 1, 0, -1, -1, -1, 0, 1, 1 };
WAT_ALT wa, wadown;
G_message(_("SECTION 3: Accumulating Surface Flow with SFD."));
if (bas_thres <= 0)
threshold = 60;
else
threshold = bas_thres;
for (killer = 0; killer < do_points; killer++) {
G_percent(killer, do_points, 1);
seg_get(&astar_pts, (char *)&point, 0, killer);
r = point.r;
c = point.c;
bseg_get(&asp, &asp_val, r, c);
if (asp_val) {
dr = r + asp_r[ABS(asp_val)];
dc = c + asp_c[ABS(asp_val)];
}
/* skip user-defined depressions */
else
dr = dc = -1;
bseg_get(&bitflags, &this_flag_value, r, c);
FLAG_UNSET(this_flag_value, WORKEDFLAG);
if (dr >= 0 && dr < nrows && dc >= 0 && dc < ncols) {
/* TODO: do not distribute flow along edges, this causes artifacts */
seg_get(&watalt, (char *)&wa, r, c);
value = wa.wat;
is_swale = FLAG_GET(this_flag_value, SWALEFLAG);
if (fabs(value) >= threshold && !is_swale) {
is_swale = 1;
FLAG_SET(this_flag_value, SWALEFLAG);
}
seg_get(&watalt, (char *)&wadown, dr, dc);
valued = wadown.wat;
if (value > 0) {
if (valued > 0)
valued += value;
else
valued -= value;
}
else {
if (valued < 0)
valued += value;
else
valued = value - valued;
}
wadown.wat = valued;
seg_put(&watalt, (char *)&wadown, dr, dc);
/* update asp for depression */
if (is_swale || fabs(valued) >= threshold) {
bseg_get(&bitflags, &flag_value, dr, dc);
FLAG_SET(flag_value, SWALEFLAG);
bseg_put(&bitflags, &flag_value, dr, dc);
is_swale = 1;
}
else {
if (er_flag && !is_swale && !FLAG_GET(this_flag_value, RUSLEBLOCKFLAG))
slope_length(r, c, dr, dc);
}
}
bseg_put(&bitflags, &this_flag_value, r, c);
}
G_percent(do_points, do_points, 1); /* finish it */
seg_close(&astar_pts);
return 0;
}
int do_cum_mfd(void)
{
int r, c, dr, dc;
DCELL value, valued, *wat_nbr;
POINT point;
WAT_ALT wa;
int killer, threshold;
/* MFD */
int mfd_cells, stream_cells, swale_cells, astar_not_set, is_null;
double *dist_to_nbr, *weight, sum_weight, max_weight;
int r_nbr, c_nbr, r_max, c_max, ct_dir, np_side, max_side;
double dx, dy;
CELL ele, *ele_nbr;
char asp_val, asp_val_down;
double prop, max_acc;
int workedon, edge, is_swale, flat;
char *flag_nbr, this_flag_value, flag_value;
int asp_r[9] = { 0, -1, -1, -1, 0, 1, 1, 1, 0 };
int asp_c[9] = { 0, 1, 0, -1, -1, -1, 0, 1, 1 };
G_message(_("SECTION 3: Accumulating Surface Flow with MFD."));
G_debug(1, "MFD convergence factor set to %d.", c_fac);
/* distances to neighbours */
dist_to_nbr = (double *)G_malloc(sides * sizeof(double));
weight = (double *)G_malloc(sides * sizeof(double));
for (ct_dir = 0; ct_dir < sides; ct_dir++) {
/* get r, c (r_nbr, c_nbr) for neighbours */
r_nbr = nextdr[ct_dir];
c_nbr = nextdc[ct_dir];
/* account for rare cases when ns_res != ew_res */
dy = ABS(r_nbr) * window.ns_res;
dx = ABS(c_nbr) * window.ew_res;
if (ct_dir < 4)
dist_to_nbr[ct_dir] = dx + dy;
else
dist_to_nbr[ct_dir] = sqrt(dx * dx + dy * dy);
}
flag_nbr = (char *)G_malloc(sides * sizeof(char));
wat_nbr = (DCELL *)G_malloc(sides * sizeof(DCELL));
ele_nbr = (CELL *)G_malloc(sides * sizeof(CELL));
workedon = 0;
if (bas_thres <= 0)
threshold = 60;
else
threshold = bas_thres;
for (killer = 0; killer < do_points; killer++) {
G_percent(killer, do_points, 1);
seg_get(&astar_pts, (char *)&point, 0, killer);
r = point.r;
c = point.c;
bseg_get(&asp, &asp_val, r, c);
if (asp_val) {
dr = r + asp_r[ABS(asp_val)];
dc = c + asp_c[ABS(asp_val)];
}
/* skip user-defined depressions */
else
dr = dc = -1;
/* WORKEDFLAG has been set during A* Search
* reversed meaning here: 0 = done, 1 = not yet done */
bseg_get(&bitflags, &this_flag_value, r, c);
FLAG_UNSET(this_flag_value, WORKEDFLAG);
if (dr >= 0 && dr < nrows && dc >= 0 && dc < ncols) {
r_max = dr;
c_max = dc;
seg_get(&watalt, (char *)&wa, r, c);
value = wa.wat;
/* get weights */
max_weight = 0;
sum_weight = 0;
np_side = -1;
mfd_cells = 0;
stream_cells = 0;
swale_cells = 0;
astar_not_set = 1;
ele = wa.ele;
is_null = 0;
edge = 0;
flat = 1;
/* this loop is needed to get the sum of weights */
for (ct_dir = 0; ct_dir < sides; ct_dir++) {
/* get r, c (r_nbr, c_nbr) for neighbours */
r_nbr = r + nextdr[ct_dir];
c_nbr = c + nextdc[ct_dir];
weight[ct_dir] = -1;
wat_nbr[ct_dir] = 0;
ele_nbr[ct_dir] = 0;
/* check if neighbour is within region */
if (r_nbr >= 0 && r_nbr < nrows && c_nbr >= 0 &&
c_nbr < ncols) {
if (dr == r_nbr && dc == c_nbr)
np_side = ct_dir;
bseg_get(&bitflags, &flag_nbr[ct_dir], r_nbr, c_nbr);
seg_get(&watalt, (char *)&wa, r_nbr, c_nbr);
wat_nbr[ct_dir] = wa.wat;
ele_nbr[ct_dir] = wa.ele;
/* check for swale or stream cells */
is_swale = FLAG_GET(flag_nbr[ct_dir], SWALEFLAG);
if (is_swale)
swale_cells++;
if ((ABS(wat_nbr[ct_dir]) + 0.5) >= threshold &&
ct_dir != np_side && ele_nbr[ct_dir] > ele)
stream_cells++;
if (FLAG_GET(flag_nbr[ct_dir], WORKEDFLAG)) {
if (ele_nbr[ct_dir] != ele)
flat = 0;
edge = is_null = FLAG_GET(flag_nbr[ct_dir], NULLFLAG);
if (!is_null && ele_nbr[ct_dir] <= ele) {
if (ele_nbr[ct_dir] < ele) {
weight[ct_dir] =
mfd_pow(((ele -
ele_nbr[ct_dir]) / dist_to_nbr[ct_dir]),
c_fac);
}
if (ele_nbr[ct_dir] == ele) {
weight[ct_dir] =
mfd_pow((0.5 / dist_to_nbr[ct_dir]),
c_fac);
}
sum_weight += weight[ct_dir];
mfd_cells++;
if (weight[ct_dir] > max_weight) {
max_weight = weight[ct_dir];
}
if (dr == r_nbr && dc == c_nbr) {
astar_not_set = 0;
}
}
}
}
else
edge = 1;
if (edge)
break;
}
/* do not continue streams along edges, this causes artifacts */
if (edge) {
is_swale = FLAG_GET(this_flag_value, SWALEFLAG);
if (is_swale && asp_val > 0) {
asp_val = -1 * drain[r - r_nbr + 1][c - c_nbr + 1];
bseg_put(&asp, &asp_val, r, c);
}
bseg_put(&bitflags, &this_flag_value, r, c);
continue;
}
/* honour A * path
* mfd_cells == 0: fine, SFD along A * path
* mfd_cells == 1 && astar_not_set == 0: fine, SFD along A * path
* mfd_cells > 0 && astar_not_set == 1: A * path not included, add to mfd_cells
*/
/* MFD, A * path not included, add to mfd_cells */
if (mfd_cells > 0 && astar_not_set == 1) {
mfd_cells++;
sum_weight += max_weight;
weight[np_side] = max_weight;
max_side = np_side;
}
/* set flow accumulation for neighbours */
max_acc = -1;
max_side = np_side;
if (mfd_cells > 1) {
prop = 0.0;
for (ct_dir = 0; ct_dir < sides; ct_dir++) {
r_nbr = r + nextdr[ct_dir];
c_nbr = c + nextdc[ct_dir];
/* check if neighbour is within region */
if (r_nbr >= 0 && r_nbr < nrows && c_nbr >= 0 &&
c_nbr < ncols && weight[ct_dir] > -0.5) {
if (FLAG_GET(flag_nbr[ct_dir], WORKEDFLAG)) {
weight[ct_dir] = weight[ct_dir] / sum_weight;
/* check everything adds up to 1.0 */
prop += weight[ct_dir];
if (value > 0) {
if (wat_nbr[ct_dir] > 0)
wat_nbr[ct_dir] += value * weight[ct_dir];
else
wat_nbr[ct_dir] -= value * weight[ct_dir];
}
else {
if (wat_nbr[ct_dir] < 0)
wat_nbr[ct_dir] += value * weight[ct_dir];
else
wat_nbr[ct_dir] = value * weight[ct_dir] - wat_nbr[ct_dir];
}
valued = wat_nbr[ct_dir];
wa.wat = valued;
wa.ele = ele_nbr[ct_dir];
seg_put(&watalt, (char *)&wa, r_nbr, c_nbr);
/* get main drainage direction */
if (ABS(wat_nbr[ct_dir]) >= max_acc) {
max_acc = ABS(wat_nbr[ct_dir]);
r_max = r_nbr;
c_max = c_nbr;
max_side = ct_dir;
}
}
else if (ct_dir == np_side) {
/* check for consistency with A * path */
workedon++;
}
}
}
/* adjust main drainage direction to A* path if possible */
/*if (fabs(wat_nbr[np_side]) >= max_acc) {
max_acc = fabs(wat_nbr[np_side]);
r_max = dr;
c_max = dc;
} */
if (ABS(prop - 1.0) > 5E-6f) {
G_warning(_("MFD: cumulative proportion of flow distribution not 1.0 but %f"),
prop);
}
}
/* SFD-like accumulation */
else {
valued = wat_nbr[np_side];
if (value > 0) {
if (valued > 0)
valued += value;
else
valued -= value;
}
else {
if (valued < 0)
valued += value;
else
valued = value - valued;
}
wa.wat = valued;
wa.ele = ele_nbr[np_side];
seg_put(&watalt, (char *)&wa, dr, dc);
}
/* update asp */
if (dr != r_max || dc != c_max) {
if (asp_val < 0) {
asp_val = -1 * drain[r - r_max + 1][c - c_max + 1];
}
else
asp_val = drain[r - r_max + 1][c - c_max + 1];
bseg_put(&asp, &asp_val, r, c);
}
is_swale = FLAG_GET(this_flag_value, SWALEFLAG);
/* start new stream */
value = ABS(value) + 0.5;
if (!is_swale && (int)value >= threshold && stream_cells < 1 &&
swale_cells < 1 && !flat) {
FLAG_SET(this_flag_value, SWALEFLAG);
is_swale = 1;
}
/* continue stream */
if (is_swale) {
flag_value = flag_nbr[max_side];
FLAG_SET(flag_value, SWALEFLAG);
bseg_put(&bitflags, &flag_value, r_max, c_max);
}
else {
if (er_flag && !is_swale && !FLAG_GET(this_flag_value, RUSLEBLOCKFLAG))
slope_length(r, c, r_max, c_max);
}
}
bseg_put(&bitflags, &this_flag_value, r, c);
}
G_percent(do_points, do_points, 1); /* finish it */
if (workedon)
G_warning(_("MFD: A * path already processed when distributing flow: %d of %d cells"),
workedon, do_points);
seg_close(&astar_pts);
G_free(dist_to_nbr);
G_free(weight);
G_free(wat_nbr);
G_free(ele_nbr);
G_free(flag_nbr);
return 0;
}
int do_astar(void)
{
int doer, count;
int upr, upc, r = -1, c = -1, ct_dir;
CELL alt_val, alt_nbr[8];
WAT_ALT wa;
char asp_val;
char flag_value, is_in_list, is_worked;
HEAP_PNT heap_p;
/* sides
* |7|1|4|
* |2| |3|
* |5|0|6|
*/
int nbr_ew[8] = { 0, 1, 2, 3, 1, 0, 0, 1 };
int nbr_ns[8] = { 0, 1, 2, 3, 3, 2, 3, 2 };
double dx, dy, dist_to_nbr[8], ew_res, ns_res;
double slope[8];
int skip_diag;
int count_edge = 0, count_diag = 0, count_edge_sink = 0, count_diag_sink = 0;
G_message(_("SECTION 2: A* Search."));
for (ct_dir = 0; ct_dir < sides; ct_dir++) {
/* get r, c (upr, upc) for neighbours */
upr = nextdr[ct_dir];
upc = nextdc[ct_dir];
/* account for rare cases when ns_res != ew_res */
dy = ABS(upr) * window.ns_res;
dx = ABS(upc) * window.ew_res;
if (ct_dir < 4)
dist_to_nbr[ct_dir] = dx + dy;
else
dist_to_nbr[ct_dir] = sqrt(dx * dx + dy * dy);
}
ew_res = window.ew_res;
ns_res = window.ns_res;
if (heap_size == 0)
G_fatal_error(_("No seeds for A* Search"));
G_debug(1, "heap size %d, points %d", heap_size, do_points);
count = 0;
doer = do_points - 1;
/* A* Search: search uphill, get downhill paths */
while (heap_size > 0) {
G_percent(count++, do_points, 1);
heap_p = drop_pt();
r = heap_p.pnt.r;
c = heap_p.pnt.c;
G_debug(3, "heap size %d, r %d, c %d", heap_size, r, c);
alt_val = heap_p.ele;
/* check all neighbours, breadth first search */
for (ct_dir = 0; ct_dir < sides; ct_dir++) {
/* get r, c (upr, upc) for this neighbour */
upr = r + nextdr[ct_dir];
upc = c + nextdc[ct_dir];
slope[ct_dir] = alt_nbr[ct_dir] = 0;
/* check if upr, upc are within region */
if (upr >= 0 && upr < nrows && upc >= 0 && upc < ncols) {
bseg_get(&bitflags, &flag_value, upr, upc);
is_in_list = FLAG_GET(flag_value, INLISTFLAG);
is_worked = FLAG_GET(flag_value, WORKEDFLAG);
skip_diag = 0;
/* avoid diagonal flow direction bias */
if (!is_worked) {
seg_get(&watalt, (char *)&wa, upr, upc);
alt_nbr[ct_dir] = wa.ele;
slope[ct_dir] =
get_slope2(alt_val, alt_nbr[ct_dir],
dist_to_nbr[ct_dir]);
}
if (!is_in_list) {
if (ct_dir > 3 && slope[ct_dir] > 0) {
if (slope[nbr_ew[ct_dir]] > 0) {
/* slope to ew nbr > slope to center */
if (slope[ct_dir] <
get_slope2(alt_nbr[nbr_ew[ct_dir]],
alt_nbr[ct_dir], ew_res))
skip_diag = 1;
}
if (!skip_diag && slope[nbr_ns[ct_dir]] > 0) {
/* slope to ns nbr > slope to center */
if (slope[ct_dir] <
get_slope2(alt_nbr[nbr_ns[ct_dir]],
alt_nbr[ct_dir], ns_res))
skip_diag = 1;
}
}
}
/* add neighbour as new point if not in the list */
if (is_in_list == 0 && skip_diag == 0) {
/* set flow direction */
asp_val = drain[upr - r + 1][upc - c + 1];
add_pt(upr, upc, alt_nbr[ct_dir]);
bseg_put(&asp, &asp_val, upr, upc);
FLAG_SET(flag_value, INLISTFLAG);
bseg_put(&bitflags, &flag_value, upr, upc);
if (alt_nbr[ct_dir] < alt_val) {
if (ct_dir < 4)
count_edge_sink++;
else
count_diag_sink++;
}
/* includes flat areas */
else {
if (ct_dir < 4)
count_edge++;
else
count_diag++;
}
}
else if (is_in_list && is_worked == 0 &&
FLAG_GET(flag_value, EDGEFLAG)) {
/* neighbour is edge in list, not yet worked */
bseg_get(&asp, &asp_val, upr, upc);
if (asp_val < 0) {
/* adjust flow direction for edge cell */
asp_val = drain[upr - r + 1][upc - c + 1];
bseg_put(&asp, &asp_val, upr, upc);
seg_get(&watalt, (char *)&wa, r, c);
if (wa.wat > 0) {
wa.wat = -wa.wat;
seg_put(&watalt, (char *)&wa, r, c);
}
}
/* neighbour is inside real depression, not yet worked */
else if (asp_val == 0) {
asp_val = drain[upr - r + 1][upc - c + 1];
bseg_put(&asp, &asp_val, upr, upc);
}
}
}
}
/* add astar points to sorted list for flow accumulation */
seg_put(&astar_pts, (char *)&heap_p.pnt, 0, doer);
doer--;
bseg_get(&bitflags, &flag_value, r, c);
FLAG_SET(flag_value, WORKEDFLAG);
bseg_put(&bitflags, &flag_value, r, c);
}
if (doer != -1)
G_fatal_error(_("bug in A* Search: doer %d heap size %d count %d"),
doer, heap_size, count);
seg_close(&search_heap);
G_percent(count, do_points, 1); /* finish it */
G_debug(1, "edge direction: %d (%.2f%%)", count_edge, (double) 100. * count_edge / (count_edge + count_diag));
G_debug(1, "diag direction: %d (%.2f%%)", count_diag, (double) 100. * count_diag / (count_edge + count_diag));
G_debug(1, "edge out of depression: %d (%.2f%%)", count_edge_sink, (double) 100. * count_edge_sink / (count_edge_sink + count_diag_sink));
G_debug(1, "diag out of depression: %d (%.2f%%)", count_diag_sink, (double) 100. * count_diag_sink / (count_edge_sink + count_diag_sink));
return 0;
}