Fix bug in grdblend when setting -I that was in fact ignored and got …

…its value from first grid. (#8407)

* Fix bug when setting -I that was in fact ignored and got its value from first grid.

* Pass some warnings to info.

src/grdblend.c

@@ -204,7 +204,8 @@ GMT_LOCAL bool grdblend_outside_cartesian_x_range (struct GMT_GRID_HEADER *h, do
 
 EXTERN_MSC void gmtlib_close_grd (struct GMT_CTRL *GMT, struct GMT_GRID *G);
 
-GMT_LOCAL int grdblend_init_blend_job (struct GMT_CTRL *GMT, char **files, unsigned int n_files, struct GMT_GRID_HEADER **h_ptr, struct GRDBLEND_INFO **blend, bool delayed, struct GMT_GRID *Grid) {
+GMT_LOCAL int grdblend_init_blend_job(struct GMT_CTRL *GMT, char **files, unsigned int n_files, struct GMT_GRID_HEADER **h_ptr,
+ struct GRDBLEND_INFO **blend, bool delayed, struct GMT_GRID *Grid) {
  /* Returns how many blend files or a negative error value if something went wrong */
  int type, status, not_supported = 0, t_data, k_data = GMT_NOTSET;
  unsigned int one_or_zero, n = 0, n_scanned, do_sample, n_download = 0, down = 0, srtm_res = 0;
@@ -377,13 +378,13 @@ GMT_LOCAL int grdblend_init_blend_job (struct GMT_CTRL *GMT, char **files, unsig
  gmt_increment_adjust (GMT, wesn, GMT->common.R.inc, (GMT->common.R.active[GSET]) ? GMT->common.R.registration : B[0].G->header->registration); /* In case user specified incs using distance units we must call this here before adjusting wesn */
  inc = (GMT->common.R.active[ISET]) ? GMT->common.R.inc : B[0].G->header->inc; /* Either use -I if given else they all have the same increments */
  pp = (uint64_t)ceil ((wesn[XHI] - wesn[XLO])/inc[GMT_X] - GMT_CONV6_LIMIT);
- wesn[XHI] = wesn[XLO] + pp * B[0].G->header->inc[GMT_X];
+ wesn[XHI] = wesn[XLO] + pp * *inc;
  pp = (uint64_t)ceil ((wesn[YHI] - wesn[YLO])/inc[GMT_Y] - GMT_CONV6_LIMIT);
- wesn[YHI] = wesn[YLO] + pp * B[0].G->header->inc[GMT_Y];
+ wesn[YHI] = wesn[YLO] + pp * *inc;
  /* Create the h structure and initialize it */
  h = gmt_get_header (GMT);
  gmt_M_memcpy (h->wesn, wesn, 4, double);
- gmt_M_memcpy (h->inc, B[0].G->header->inc, 2, double);
+ gmt_M_memcpy (h->inc, inc, 2, double);
  h->registration = (GMT->common.R.active[GSET]) ? GMT->common.R.registration : B[0].G->header->registration; /* Either use -r if given else they all have the same registration */
  gmt_M_grd_setpad (GMT, h, GMT->current.io.pad); /* Assign default pad */
  gmt_set_grddim (GMT, h); /* Update dimensions */
@@ -421,14 +422,14 @@ GMT_LOCAL int grdblend_init_blend_job (struct GMT_CTRL *GMT, char **files, unsig
  Iargs[0] = Rargs[0] = '\0';
  do_sample = 0;
  if (not_supported) {
- GMT_Report (GMT->parent, GMT_MSG_WARNING,
+ GMT_Report (GMT->parent, GMT_MSG_INFORMATION,
  "File %s not supported via row-by-row read - must reformat first\n", B[n].file);
  do_sample |= 2;
  }
  if (fabs((t->inc[GMT_X] - h->inc[GMT_X]) / h->inc[GMT_X]) > 0.002 ||
  fabs((t->inc[GMT_Y] - h->inc[GMT_Y]) / h->inc[GMT_Y]) > 0.002) {
  sprintf (Iargs, "-I%.12g/%.12g", h->inc[GMT_X], h->inc[GMT_Y]);
- GMT_Report (GMT->parent, GMT_MSG_WARNING, "File %s has different increments (%.12g/%.12g) than the output grid (%.12g/%.12g) - must resample\n",
+ GMT_Report (GMT->parent, GMT_MSG_INFORMATION, "File %s has different increments (%.12g/%.12g) than the output grid (%.12g/%.12g) - must resample\n",
  B[n].file, t->inc[GMT_X], t->inc[GMT_Y], h->inc[GMT_X], h->inc[GMT_Y]);
  do_sample |= 1;
  }
@@ -451,7 +452,7 @@ GMT_LOCAL int grdblend_init_blend_job (struct GMT_CTRL *GMT, char **files, unsig
  wesn[YHI] = h->wesn[YLO] + k * h->inc[GMT_Y];
  while (wesn[YHI] > t->wesn[YHI]) wesn[YHI] -= t->inc[GMT_Y]; /* Make sure we are not outside this grid */
  sprintf (Rargs, "-R%.12g/%.12g/%.12g/%.12g", wesn[XLO], wesn[XHI], wesn[YLO], wesn[YHI]);
- GMT_Report (GMT->parent, GMT_MSG_WARNING, "File %s coordinates are phase-shifted w.r.t. the output grid - must resample\n", B[n].file);
+ GMT_Report (GMT->parent, GMT_MSG_INFORMATION, "File %s coordinates are phase-shifted w.r.t. the output grid - must resample\n", B[n].file);
  do_sample |= 1;
  }
  else if (do_sample) { /* Set explicit -R to handle possible subsetting */