char* Create_segment_file (int nrows, int fract, RASTER_MAP_TYPE data_type) { int seg_fd; char* seg_name; int ncols; int submatrix_rows, submatrix_cols; int length_data_item = 0; int seg_error; ncols = G_window_cols (); if (data_type == CELL_TYPE) length_data_item = sizeof (CELL); if (data_type == FCELL_TYPE) length_data_item = sizeof (FCELL); if (data_type == DCELL_TYPE) length_data_item = sizeof (DCELL); submatrix_rows = nrows/fract + 1; submatrix_cols = ncols/fract + 1; seg_name = G_tempfile (); seg_fd = creat (seg_name, 0666); /* create a new segment file on disk */ /* size of data items (CELL, DCELL, FCELL ...) is stored in the file header */ seg_error = segment_format (seg_fd, nrows, ncols, submatrix_rows, submatrix_cols, length_data_item); if ( seg_error != 1 ) { G_fatal_error ("Cannot create segment file(s).\nCheck available diskspace and access rights."); } close (seg_fd); return seg_name; }
int seg_open(SSEG * sseg, int nrows, int ncols, int row_in_seg, int col_in_seg, int nsegs_in_memory, int size_struct) { char *filename; int errflag; int fd; sseg->filename = NULL; sseg->fd = -1; filename = G_tempfile(); if (-1 == (fd = creat(filename, 0666))) { G_warning("seg_open(): unable to create segment file"); return -2; } if (0 > (errflag = segment_format(fd, nrows, ncols, row_in_seg, col_in_seg, size_struct))) { close(fd); unlink(filename); if (errflag == -1) { G_warning("seg_open(): could not write segment file"); return -1; } else { G_warning("seg_open(): illegal configuration parameter(s)"); return -3; } } close(fd); if (-1 == (fd = open(filename, 2))) { unlink(filename); G_warning("seg_open(): unable to re-open segment file"); return -4; } if (0 > (errflag = segment_init(&(sseg->seg), fd, nsegs_in_memory))) { close(fd); unlink(filename); if (errflag == -1) { G_warning("seg_open(): could not read segment file"); return -5; } else { G_warning("seg_open(): out of memory"); return -6; } } sseg->filename = filename; sseg->fd = fd; return 0; }
int main(int argc, char **argv) { int n, verbose = 1, backrow, backcol, col, row, len, flag, srows, scols, backrow_fd, backcol_fd, path_fd, in_row_fd, in_col_fd, out_fd; const char *current_mapset, *search_mapset, *path_mapset, *backrow_mapset, *backcol_mapset, *in_row_file, *in_col_file, *out_file; CELL *cell; POINT *PRES_PT, *PRESENT_PT, *OLD_PT; struct Cell_head window; double east, north; struct Option *opt1, *opt2, *opt3, *opt4; struct Flag *flag1; struct GModule *module; G_gisinit(argv[0]); /* Set description */ module = G_define_module(); G_add_keyword(_("raster")); G_add_keyword(_("fire")); G_add_keyword(_("cumulative costs")); module->description = _("Recursively traces the least cost path backwards to " "cells from which the cumulative cost was determined."); opt1 = G_define_option(); opt1->key = "x_input"; opt1->type = TYPE_STRING; opt1->required = YES; opt1->gisprompt = "old,cell,raster"; opt1->description = _("Name of raster map containing back-path easting information"); opt2 = G_define_option(); opt2->key = "y_input"; opt2->type = TYPE_STRING; opt2->required = YES; opt2->gisprompt = "old,cell,raster"; opt2->description = _("Name of raster map containing back-path northing information"); opt3 = G_define_option(); opt3->key = "coordinate"; opt3->type = TYPE_STRING; opt3->multiple = YES; opt3->key_desc = "x,y"; opt3->description = _("The map E and N grid coordinates of starting points"); opt4 = G_define_option(); opt4->key = "output"; opt4->type = TYPE_STRING; opt4->required = YES; opt4->gisprompt = "new,cell,raster"; opt4->description = _("Name of spread path raster map"); flag1 = G_define_flag(); flag1->key = 'v'; flag1->description = _("Run verbosely"); /* Do command line parsing */ if (G_parser(argc, argv)) exit(EXIT_FAILURE); current_mapset = G_mapset(); in_row_file = G_tempfile(); in_col_file = G_tempfile(); out_file = G_tempfile(); /* Get database window parameters */ G_get_window(&window); verbose = flag1->answer; /* Check if backrow layer exists in data base */ search_mapset = ""; strcpy(backrow_layer, opt2->answer); strcpy(backcol_layer, opt1->answer); backrow_mapset = G_find_raster(backrow_layer, search_mapset); backcol_mapset = G_find_raster(backcol_layer, search_mapset); if (backrow_mapset == NULL) G_fatal_error("%s - not found", backrow_layer); if (backcol_mapset == NULL) G_fatal_error("%s - not found", backcol_layer); search_mapset = ""; strcpy(path_layer, opt4->answer); path_mapset = G_find_raster(path_layer, search_mapset); /* find number of rows and cols in window */ nrows = Rast_window_rows(); ncols = Rast_window_cols(); cell = Rast_allocate_c_buf(); /* Open back cell layers for reading */ backrow_fd = Rast_open_old(backrow_layer, backrow_mapset); backcol_fd = Rast_open_old(backcol_layer, backcol_mapset); /* Parameters for map submatrices */ len = sizeof(CELL); srows = nrows / 4 + 1; scols = ncols / 4 + 1; if (verbose) G_message ("\nReading the input map -%s- and -%s- and creating some temporary files...", backrow_layer, backcol_layer); /* Create segmented files for back cell and output layers */ in_row_fd = creat(in_row_file, 0666); segment_format(in_row_fd, nrows, ncols, srows, scols, len); close(in_row_fd); in_col_fd = creat(in_col_file, 0666); segment_format(in_col_fd, nrows, ncols, srows, scols, len); close(in_col_fd); out_fd = creat(out_file, 0666); segment_format(out_fd, nrows, ncols, srows, scols, len); close(out_fd); /* Open initialize and segment all files */ in_row_fd = open(in_row_file, 2); segment_init(&in_row_seg, in_row_fd, 4); in_col_fd = open(in_col_file, 2); segment_init(&in_col_seg, in_col_fd, 4); out_fd = open(out_file, 2); segment_init(&out_seg, out_fd, 4); /* Write the back cell layers in the segmented files, and * Change UTM coordinates to ROWs and COLUMNs */ for (row = 0; row < nrows; row++) { Rast_get_c_row(backrow_fd, cell, row); for (col = 0; col < ncols; col++) if (cell[col] > 0) cell[col] = (window.north - cell[col]) / window.ns_res /* - 0.5 */ ; else cell[col] = -1; segment_put_row(&in_row_seg, cell, row); Rast_get_c_row(backcol_fd, cell, row); for (col = 0; col < ncols; col++) if (cell[col] > 0) cell[col] = (cell[col] - window.west) / window.ew_res /* - 0.5 */ ; segment_put_row(&in_col_seg, cell, row); } /* Convert easting and northing from the command line to row and col */ if (opt3->answer) { for (n = 0; opt3->answers[n] != NULL; n += 2) { G_scan_easting(opt3->answers[n], &east, G_projection()); G_scan_northing(opt3->answers[n + 1], &north, G_projection()); row = (window.north - north) / window.ns_res; col = (east - window.west) / window.ew_res; /* ignore pt outside window */ if (east < window.west || east > window.east || north < window.south || north > window.north) { G_warning("Ignoring point outside window: "); G_warning(" %.4f,%.4f", east, north); continue; } value = (char *)&backrow; segment_get(&in_row_seg, value, row, col); /* ignore pt in no-data area */ if (backrow < 0) { G_warning("Ignoring point in NO-DATA area :"); G_warning(" %.4f,%.4f", east, north); continue; } value = (char *)&backcol; segment_get(&in_col_seg, value, row, col); insert(&PRESENT_PT, row, col, backrow, backcol); } } /* Set flag according to input */ if (path_mapset != NULL) { if (head_start_pt == NULL) /*output layer exists and start pts are not given on cmd line */ flag = 1; /* output layer exists and starting pts are given on cmd line */ else flag = 2; } else flag = 3; /* output layer does not previously exist */ /* If the output layer containing the starting positions */ /* create a linked list of of them */ if (flag == 1) { path_fd = Rast_open_old(path_layer, path_mapset); /* Search for the marked starting pts and make list */ for (row = 0; row < nrows; row++) { Rast_get_c_row(path_fd, cell, row); for (col = 0; col < ncols; col++) { if (cell[col] > 0) { value = (char *)&backrow; segment_get(&in_row_seg, value, row, col); /* ignore pt in no-data area */ if (backrow < 0) { G_warning("Ignoring point in NO-DATA area:"); G_warning(" %.4f,%.4f\n", window.west + window.ew_res * (col + 0.5), window.north - window.ns_res * (row + 0.5)); continue; } value = (char *)&backcol; segment_get(&in_col_seg, value, row, col); insert(&PRESENT_PT, row, col, backrow, backcol); } } /* loop over cols */ } /* loop over rows */ Rast_close(path_fd); } /* loop over the starting points to find the least cost paths */ if (verbose) G_message("\nFinding the least cost paths ..."); PRES_PT = head_start_pt; while (PRES_PT != NULL) { path_finder(PRES_PT->row, PRES_PT->col, PRES_PT->backrow, PRES_PT->backcol); OLD_PT = PRES_PT; PRES_PT = NEXT_PT; G_free(OLD_PT); } /* Write pending updates by segment_put() to outputmap */ segment_flush(&out_seg); if (verbose) G_message("\nWriting the output map -%s-...", path_layer); path_fd = Rast_open_c_new(path_layer); for (row = 0; row < nrows; row++) { segment_get_row(&out_seg, cell, row); Rast_put_row(path_fd, cell, CELL_TYPE); } if (verbose) G_message("finished."); segment_release(&in_row_seg); /* release memory */ segment_release(&in_col_seg); segment_release(&out_seg); close(in_row_fd); /* close all files */ close(in_col_fd); close(out_fd); Rast_close(path_fd); Rast_close(backrow_fd); Rast_close(backcol_fd); unlink(in_row_file); /* remove submatrix files */ unlink(in_col_file); unlink(out_file); exit(EXIT_SUCCESS); }