/*!
* \brief Read floating-point range
*
* Read the floating point range file <i>drange</i>. This file is
* written in binary using XDR format.
*
* An empty range file indicates that the min, max are undefined. This
* is a valid case, and the result should be an initialized range
* struct with no defined min/max. If the range file is missing and
* the map is a floating-point map, this function will create a
* default range by calling G_construct_default_range().
*
* \param name map name
* \param mapset mapset name
* \param drange pointer to FPRange structure which holds fp range
*
* \return 1 on success
* \return 2 range is empty
* \return -1 on error
*/
int Rast_read_fp_range(const char *name, const char *mapset,
struct FPRange *drange)
{
struct Range range;
int fd;
char xdr_buf[2][XDR_DOUBLE_NBYTES];
DCELL dcell1, dcell2;
Rast_init();
Rast_init_fp_range(drange);
if (Rast_map_type(name, mapset) == CELL_TYPE) {
/* if map is integer
read integer range and convert it to double */
if (Rast_read_range(name, mapset, &range) >= 0) {
/* if the integer range is empty */
if (range.first_time)
return 2;
Rast_update_fp_range((DCELL) range.min, drange);
Rast_update_fp_range((DCELL) range.max, drange);
return 1;
}
return -1;
}
fd = -1;
if (G_find_file2_misc("cell_misc", "f_range", name, mapset)) {
fd = G_open_old_misc("cell_misc", "f_range", name, mapset);
if (fd < 0) {
G_warning(_("Unable to read fp range file for <%s>"),
G_fully_qualified_name(name, mapset));
return -1;
}
if (read(fd, xdr_buf, sizeof(xdr_buf)) != sizeof(xdr_buf)) {
/* if the f_range file exists, but empty file, meaning Nulls */
close(fd);
G_debug(1, "Empty fp range file meaning Nulls for <%s>",
G_fully_qualified_name(name, mapset));
return 2;
}
G_xdr_get_double(&dcell1, xdr_buf[0]);
G_xdr_get_double(&dcell2, xdr_buf[1]);
Rast_update_fp_range(dcell1, drange);
Rast_update_fp_range(dcell2, drange);
close(fd);
}
return 1;
}
static void cell_values_double(int fd, const unsigned char *data,
const COLUMN_MAPPING * cmap, int nbytes,
void *cell, int n)
{
struct fileinfo *fcb = &R__.fileinfo[fd];
const double *work_buf = (const double *) fcb->data;
DCELL *c = cell;
int i;
for (i = 0; i < n; i++) {
if (!cmap[i]) {
c[i] = 0;
continue;
}
G_xdr_get_double(&c[i], &work_buf[cmap[i]-1]);
}
}
