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 sg_factor(void)
{
int r, c;
CELL low_elev, hih_elev;
double height, length, S, sin_theta;
WAT_ALT wa;
ASP_FLAG af;
G_message(_("SECTION 5: RUSLE LS and/or S factor determination."));
for (r = nrows - 1; r >= 0; r--) {
G_percent(nrows - r, nrows, 3);
for (c = ncols - 1; c >= 0; c--) {
seg_get(&aspflag, (char *)&af, r, c);
if (FLAG_GET(af.flag, NULLFLAG))
continue;
seg_get(&watalt, (char *) &wa, r, c);
low_elev = wa.ele;
cseg_get(&r_h, &hih_elev, r, c);
dseg_get(&s_l, &length, r, c);
height = 1.0 * (hih_elev - low_elev) / ele_scale;
if (length > max_length) {
height *= max_length / length;
length = max_length;
}
sin_theta = height / sqrt(height * height + length * length);
if (height / length < .09)
S = 10.8 * sin_theta + .03;
else
S = 16.8 * sin_theta - .50;
if (ls_flag) {
length *= METER_TO_FOOT;
len_slp_equ(length, sin_theta, S, r, c);
}
if (sg_flag) {
dseg_put(&s_g, &S, r, c);
}
}
}
G_percent(nrows, nrows, 1); /* finish it */
return 0;
}
int len_slp_equ(double slope_length, double sin_theta, double S, int r, int c)
{
double rill, s_l_exp, /* m */
rill_ratio, /* Beta */
LS;
rill_ratio = (sin_theta / 0.0896) / (3.0 * pow(sin_theta, 0.8) + 0.56);
if (ril_flag) {
dseg_get(&ril, &rill, r, c);
}
else if (ril_value >= 0.0) {
rill = ril_value;
}
else
rill = 0.0;
/* rill_ratio equation from Steve Warren */
rill_ratio *= .5 + .005 * rill + .0001 * rill * rill;
s_l_exp = rill_ratio / (1 + rill_ratio);
LS = S * pow((slope_length / 72.6), s_l_exp);
dseg_put(&l_s, &LS, r, c);
return 0;
}
int init_vars(int argc, char *argv[])
{
int r, c;
int ele_fd, wat_fd, fd = -1;
int seg_rows, seg_cols, num_cseg_total, num_open_segs, num_open_array_segs;
double memory_divisor, heap_mem, seg_factor, disk_space;
/* int page_block, num_cseg; */
int max_bytes;
CELL *buf, alt_value, *alt_value_buf, block_value;
char asp_value;
DCELL wat_value;
DCELL dvalue;
WAT_ALT wa, *wabuf;
ASP_FLAG af, af_nbr, *afbuf;
char MASK_flag;
void *elebuf, *ptr, *watbuf, *watptr;
int ele_map_type, wat_map_type;
size_t ele_size, wat_size;
int ct_dir, r_nbr, c_nbr;
G_gisinit(argv[0]);
/* input */
ele_flag = pit_flag = run_flag = ril_flag = 0;
/* output */
wat_flag = asp_flag = bas_flag = seg_flag = haf_flag = tci_flag = 0;
bas_thres = 0;
/* shed, unused */
arm_flag = dis_flag = 0;
/* RUSLE */
ob_flag = st_flag = sl_flag = sg_flag = ls_flag = er_flag = 0;
nxt_avail_pt = 0;
/* dep_flag = 0; */
max_length = d_zero = 0.0;
d_one = 1.0;
ril_value = -1.0;
/* dep_slope = 0.0; */
max_bytes = 0;
sides = 8;
mfd = 1;
c_fac = 5;
abs_acc = 0;
ele_scale = 1;
segs_mb = 300;
/* scan options */
for (r = 1; r < argc; r++) {
if (sscanf(argv[r], "elevation=%s", ele_name) == 1)
ele_flag++;
else if (sscanf(argv[r], "accumulation=%s", wat_name) == 1)
wat_flag++;
else if (sscanf(argv[r], "tci=%s", tci_name) == 1)
tci_flag++;
else if (sscanf(argv[r], "drainage=%s", asp_name) == 1)
asp_flag++;
else if (sscanf(argv[r], "depression=%s", pit_name) == 1)
pit_flag++;
else if (sscanf(argv[r], "threshold=%d", &bas_thres) == 1) ;
else if (sscanf(argv[r], "max_slope_length=%lf", &max_length) == 1) ;
else if (sscanf(argv[r], "basin=%s", bas_name) == 1)
bas_flag++;
else if (sscanf(argv[r], "stream=%s", seg_name) == 1)
seg_flag++;
else if (sscanf(argv[r], "half_basin=%s", haf_name) == 1)
haf_flag++;
else if (sscanf(argv[r], "flow=%s", run_name) == 1)
run_flag++;
else if (sscanf(argv[r], "ar=%s", arm_name) == 1)
arm_flag++;
/* slope length
else if (sscanf(argv[r], "slope_length=%s", sl_name) == 1)
sl_flag++; */
else if (sscanf(argv[r], "slope_steepness=%s", sg_name) == 1)
sg_flag++;
else if (sscanf(argv[r], "length_slope=%s", ls_name) == 1)
ls_flag++;
else if (sscanf(argv[r], "blocking=%s", ob_name) == 1)
ob_flag++;
else if (sscanf(argv[r], "memory=%lf", &segs_mb) == 1) ;
else if (sscanf(argv[r], "disturbed_land=%s", ril_name) == 1) {
if (sscanf(ril_name, "%lf", &ril_value) == 0) {
ril_value = -1.0;
ril_flag++;
}
}
/* slope deposition
else if (sscanf (argv[r], "sd=%[^\n]", dep_name) == 1) dep_flag++; */
else if (sscanf(argv[r], "-%d", &sides) == 1) {
if (sides != 4)
usage(argv[0]);
}
else if (sscanf(argv[r], "convergence=%d", &c_fac) == 1) ;
else if (strcmp(argv[r], "-s") == 0)
mfd = 0;
else if (strcmp(argv[r], "-a") == 0)
abs_acc = 1;
else
usage(argv[0]);
}
/* check options */
if (mfd == 1 && (c_fac < 1 || c_fac > 10)) {
G_fatal_error("Convergence factor must be between 1 and 10.");
}
if ((ele_flag != 1)
||
((arm_flag == 1) &&
((bas_thres <= 0) || ((haf_flag != 1) && (bas_flag != 1))))
||
((bas_thres <= 0) &&
((bas_flag == 1) || (seg_flag == 1) || (haf_flag == 1) ||
(sl_flag == 1) || (sg_flag == 1) || (ls_flag == 1)))
)
usage(argv[0]);
tot_parts = 4;
if (sl_flag || sg_flag || ls_flag)
er_flag = 1;
/* do RUSLE */
if (er_flag)
tot_parts++;
/* define basins */
if (seg_flag || bas_flag || haf_flag)
tot_parts++;
G_message(_n("SECTION 1 beginning: Initiating Variables. %d section total.",
"SECTION 1 beginning: Initiating Variables. %d sections total.",
tot_parts),
tot_parts);
this_mapset = G_mapset();
/* for sd factor
if (dep_flag) {
if (sscanf (dep_name, "%lf", &dep_slope) != 1) {
dep_flag = -1;
}
}
*/
G_get_set_window(&window);
nrows = Rast_window_rows();
ncols = Rast_window_cols();
if (max_length <= d_zero)
max_length = 10 * nrows * window.ns_res + 10 * ncols * window.ew_res;
if (window.ew_res < window.ns_res)
half_res = .5 * window.ew_res;
else
half_res = .5 * window.ns_res;
diag = sqrt(window.ew_res * window.ew_res +
window.ns_res * window.ns_res);
if (sides == 4)
diag *= 0.5;
/* Segment rows and cols: 64 */
seg_rows = SROW;
seg_cols = SCOL;
/* seg_factor * <size in bytes> = segment size in KB */
seg_factor = seg_rows * seg_rows / 1024.;
if (segs_mb < 3.0) {
segs_mb = 3;
G_warning(_("Maximum memory to be used was smaller than 3 MB,"
" set to 3 MB."));
}
/* balance segment files */
/* elevation + accumulation: * 2 */
memory_divisor = sizeof(WAT_ALT) * 2;
disk_space = sizeof(WAT_ALT);
/* aspect and flags: * 4 */
memory_divisor += sizeof(ASP_FLAG) * 4;
disk_space += sizeof(ASP_FLAG);
/* astar_points: / 16 */
/* ideally only a few but large segments */
memory_divisor += sizeof(POINT) / 16.;
disk_space += sizeof(POINT);
/* heap points: / 4 */
memory_divisor += sizeof(HEAP_PNT) / 4.;
disk_space += sizeof(HEAP_PNT);
/* TCI: as is */
if (tci_flag) {
memory_divisor += sizeof(double);
disk_space += sizeof(double);
}
/* RUSLE */
if (er_flag) {
/* r_h */
memory_divisor += 4;
disk_space += 4;
/* s_l */
memory_divisor += 8;
disk_space += 8;
/* s_g */
if (sg_flag) {
memory_divisor += 8;
disk_space += 8;
}
/* l_s */
if (ls_flag) {
memory_divisor += 8;
disk_space += 8;
}
/* ril */
if (ril_flag) {
memory_divisor += 8;
disk_space += 8;
}
}
/* KB -> MB */
memory_divisor = memory_divisor * seg_factor / 1024.;
disk_space = disk_space * seg_factor / 1024.;
num_open_segs = segs_mb / memory_divisor;
heap_mem = num_open_segs * seg_factor * sizeof(HEAP_PNT) / (4. * 1024.);
G_debug(1, "segs MB: %.0f", segs_mb);
G_debug(1, "region rows: %d", nrows);
G_debug(1, "seg rows: %d", seg_rows);
G_debug(1, "region cols: %d", ncols);
G_debug(1, "seg cols: %d", seg_cols);
num_cseg_total = nrows / SROW + 1;
G_debug(1, " row segments:\t%d", num_cseg_total);
num_cseg_total = ncols / SCOL + 1;
G_debug(1, "column segments:\t%d", num_cseg_total);
num_cseg_total = (ncols / seg_cols + 1) * (nrows / seg_rows + 1);
G_debug(1, " total segments:\t%d", num_cseg_total);
G_debug(1, " open segments:\t%d", num_open_segs);
/* nonsense to have more segments open than exist */
if (num_open_segs > num_cseg_total)
num_open_segs = num_cseg_total;
G_debug(1, " open segments after adjusting:\t%d", num_open_segs);
disk_space *= num_cseg_total;
if (disk_space < 1024.0)
G_verbose_message(_("Will need up to %.2f MB of disk space"), disk_space);
else
G_verbose_message(_("Will need up to %.2f GB (%.0f MB) of disk space"),
disk_space / 1024.0, disk_space);
if (er_flag) {
cseg_open(&r_h, seg_rows, seg_cols, num_open_segs);
cseg_read_cell(&r_h, ele_name, "");
}
/* read elevation input and mark NULL/masked cells */
/* scattered access: alt, watalt, bitflags, asp */
seg_open(&watalt, nrows, ncols, seg_rows, seg_cols, num_open_segs * 2, sizeof(WAT_ALT));
seg_open(&aspflag, nrows, ncols, seg_rows, seg_cols, num_open_segs * 4, sizeof(ASP_FLAG));
if (tci_flag)
dseg_open(&tci, seg_rows, seg_cols, num_open_segs);
/* open elevation input */
ele_fd = Rast_open_old(ele_name, "");
ele_map_type = Rast_get_map_type(ele_fd);
ele_size = Rast_cell_size(ele_map_type);
elebuf = Rast_allocate_buf(ele_map_type);
afbuf = G_malloc(ncols * sizeof(ASP_FLAG));
if (ele_map_type == FCELL_TYPE || ele_map_type == DCELL_TYPE)
ele_scale = 1000; /* should be enough to do the trick */
/* initial flow accumulation */
if (run_flag) {
wat_fd = Rast_open_old(run_name, "");
wat_map_type = Rast_get_map_type(ele_fd);
wat_size = Rast_cell_size(ele_map_type);
watbuf = Rast_allocate_buf(ele_map_type);
}
else {
watbuf = watptr = NULL;
wat_fd = wat_size = wat_map_type = -1;
}
wabuf = G_malloc(ncols * sizeof(WAT_ALT));
alt_value_buf = Rast_allocate_buf(CELL_TYPE);
/* read elevation input and mark NULL/masked cells */
G_message("SECTION 1a: Mark masked and NULL cells");
MASK_flag = 0;
do_points = (GW_LARGE_INT) nrows * ncols;
for (r = 0; r < nrows; r++) {
G_percent(r, nrows, 1);
Rast_get_row(ele_fd, elebuf, r, ele_map_type);
ptr = elebuf;
if (run_flag) {
Rast_get_row(wat_fd, watbuf, r, wat_map_type);
watptr = watbuf;
}
for (c = 0; c < ncols; c++) {
afbuf[c].flag = 0;
afbuf[c].asp = 0;
/* check for masked and NULL cells */
if (Rast_is_null_value(ptr, ele_map_type)) {
FLAG_SET(afbuf[c].flag, NULLFLAG);
FLAG_SET(afbuf[c].flag, INLISTFLAG);
FLAG_SET(afbuf[c].flag, WORKEDFLAG);
Rast_set_c_null_value(&alt_value, 1);
/* flow accumulation */
Rast_set_d_null_value(&wat_value, 1);
do_points--;
}
else {
if (ele_map_type == CELL_TYPE) {
alt_value = *((CELL *)ptr);
}
else if (ele_map_type == FCELL_TYPE) {
dvalue = *((FCELL *)ptr);
dvalue *= ele_scale;
alt_value = ele_round(dvalue);
}
else if (ele_map_type == DCELL_TYPE) {
dvalue = *((DCELL *)ptr);
dvalue *= ele_scale;
alt_value = ele_round(dvalue);
}
/* flow accumulation */
if (run_flag) {
if (Rast_is_null_value(watptr, wat_map_type)) {
wat_value = 0; /* ok ? */
}
else {
if (wat_map_type == CELL_TYPE) {
wat_value = *((CELL *)watptr);
}
else if (wat_map_type == FCELL_TYPE) {
wat_value = *((FCELL *)watptr);
}
else if (wat_map_type == DCELL_TYPE) {
wat_value = *((DCELL *)watptr);
}
}
}
else {
wat_value = 1;
}
}
wabuf[c].wat = wat_value;
wabuf[c].ele = alt_value;
alt_value_buf[c] = alt_value;
ptr = G_incr_void_ptr(ptr, ele_size);
if (run_flag) {
watptr = G_incr_void_ptr(watptr, wat_size);
}
}
seg_put_row(&watalt, (char *) wabuf, r);
seg_put_row(&aspflag, (char *)afbuf, r);
if (er_flag) {
cseg_put_row(&r_h, alt_value_buf, r);
}
}
G_percent(nrows, nrows, 1); /* finish it */
Rast_close(ele_fd);
G_free(wabuf);
G_free(afbuf);
if (run_flag) {
Rast_close(wat_fd);
G_free(watbuf);
}
MASK_flag = (do_points < nrows * ncols);
/* do RUSLE */
if (er_flag) {
if (ob_flag) {
fd = Rast_open_old(ob_name, "");
buf = Rast_allocate_c_buf();
for (r = 0; r < nrows; r++) {
G_percent(r, nrows, 1);
Rast_get_c_row(fd, buf, r);
for (c = 0; c < ncols; c++) {
block_value = buf[c];
if (!Rast_is_c_null_value(&block_value) && block_value) {
seg_get(&aspflag, (char *)&af, r, c);
FLAG_SET(af.flag, RUSLEBLOCKFLAG);
seg_put(&aspflag, (char *)&af, r, c);
}
}
}
G_percent(nrows, nrows, 1); /* finish it */
Rast_close(fd);
G_free(buf);
}
if (ril_flag) {
dseg_open(&ril, seg_rows, seg_cols, num_open_segs);
dseg_read_cell(&ril, ril_name, "");
}
/* dseg_open(&slp, SROW, SCOL, num_open_segs); */
dseg_open(&s_l, seg_rows, seg_cols, num_open_segs);
if (sg_flag)
dseg_open(&s_g, seg_rows, seg_cols, num_open_segs);
if (ls_flag)
dseg_open(&l_s, seg_rows, seg_cols, num_open_segs);
}
G_debug(1, "open segments for A* points");
/* columns per segment */
seg_cols = seg_rows * seg_rows;
num_cseg_total = do_points / seg_cols;
if (do_points % seg_cols > 0)
num_cseg_total++;
/* no need to have more segments open than exist */
num_open_array_segs = num_open_segs / 16.;
if (num_open_array_segs > num_cseg_total)
num_open_array_segs = num_cseg_total;
if (num_open_array_segs < 1)
num_open_array_segs = 1;
seg_open(&astar_pts, 1, do_points, 1, seg_cols, num_open_array_segs,
sizeof(POINT));
/* one-based d-ary search_heap with astar_pts */
G_debug(1, "open segments for A* search heap");
G_debug(1, "heap memory %.2f MB", heap_mem);
/* columns per segment */
/* larger is faster */
seg_cols = seg_rows * seg_rows;
num_cseg_total = do_points / seg_cols;
if (do_points % seg_cols > 0)
num_cseg_total++;
/* no need to have more segments open than exist */
num_open_array_segs = (1 << 20) * heap_mem / (seg_cols * sizeof(HEAP_PNT));
if (num_open_array_segs > num_cseg_total)
num_open_array_segs = num_cseg_total;
if (num_open_array_segs < 2)
num_open_array_segs = 2;
G_debug(1, "A* search heap open segments %d, total %d",
num_open_array_segs, num_cseg_total);
/* the search heap will not hold more than 5% of all points at any given time ? */
/* chances are good that the heap will fit into one large segment */
seg_open(&search_heap, 1, do_points + 1, 1, seg_cols,
num_open_array_segs, sizeof(HEAP_PNT));
G_message(_("SECTION 1b: Determining Offmap Flow."));
/* heap is empty */
heap_size = 0;
if (pit_flag) {
buf = Rast_allocate_c_buf();
fd = Rast_open_old(pit_name, "");
}
else
buf = NULL;
first_astar = first_cum = -1;
for (r = 0; r < nrows; r++) {
G_percent(r, nrows, 1);
if (pit_flag)
Rast_get_c_row(fd, buf, r);
for (c = 0; c < ncols; c++) {
seg_get(&aspflag, (char *)&af, r, c);
if (!FLAG_GET(af.flag, NULLFLAG)) {
if (er_flag)
dseg_put(&s_l, &half_res, r, c);
asp_value = af.asp;
if (r == 0 || c == 0 || r == nrows - 1 ||
c == ncols - 1) {
/* dseg_get(&wat, &wat_value, r, c); */
seg_get(&watalt, (char *)&wa, r, c);
wat_value = wa.wat;
if (wat_value > 0) {
wat_value = -wat_value;
/* dseg_put(&wat, &wat_value, r, c); */
wa.wat = wat_value;
seg_put(&watalt, (char *)&wa, r, c);
}
if (r == 0)
asp_value = -2;
else if (c == 0)
asp_value = -4;
else if (r == nrows - 1)
asp_value = -6;
else if (c == ncols - 1)
asp_value = -8;
/* cseg_get(&alt, &alt_value, r, c); */
alt_value = wa.ele;
add_pt(r, c, alt_value);
FLAG_SET(af.flag, INLISTFLAG);
FLAG_SET(af.flag, EDGEFLAG);
af.asp = asp_value;
seg_put(&aspflag, (char *)&af, r, c);
}
else {
seg_get(&watalt, (char *)&wa, r, c);
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];
seg_get(&aspflag, (char *)&af_nbr, r_nbr, c_nbr);
if (FLAG_GET(af_nbr.flag, NULLFLAG)) {
af.asp = -1 * drain[r - r_nbr + 1][c - c_nbr + 1];
add_pt(r, c, wa.ele);
FLAG_SET(af.flag, INLISTFLAG);
FLAG_SET(af.flag, EDGEFLAG);
seg_put(&aspflag, (char *)&af, r, c);
wat_value = wa.wat;
if (wat_value > 0) {
wa.wat = -wat_value;
seg_put(&watalt, (char *)&wa, r, c);
}
break;
}
}
}
/* real depression ? */
if (pit_flag && asp_value == 0) {
if (!Rast_is_c_null_value(&buf[c]) && buf[c] != 0) {
seg_get(&watalt, (char *)&wa, r, c);
add_pt(r, c, wa.ele);
FLAG_SET(af.flag, INLISTFLAG);
FLAG_SET(af.flag, EDGEFLAG);
seg_put(&aspflag, (char *)&af, r, c);
wat_value = wa.wat;
if (wat_value > 0) {
wa.wat = -wat_value;
seg_put(&watalt, (char *)&wa, r, c);
}
}
}
} /* end non-NULL cell */
} /* end column */
}
G_percent(r, nrows, 1); /* finish it */
return 0;
}
