chore: delta symbol

nanovna.h

@@ -144,6 +144,7 @@ extern int area_height;
 extern const uint8_t x5x7_bits [];
 extern const uint8_t numfont20x22[][22 * 3];
 
+#define S_DELTA "\004"
 #define S_PI "\034"
 #define S_MICRO "\035"
 #define S_OHM "\036"

plot.c

@@ -756,34 +756,34 @@ trace_get_value_string_delta(int t, char *buf, int len, float array[101][2], int
  case TRC_LOGMAG:
  v = logmag(coeff) - logmag(coeff_ref);
  if (v == -INFINITY)
- chsnprintf(buf, len, "\004-INF dB");
+ chsnprintf(buf, len, S_DELTA "-INF dB");
  else
- chsnprintf(buf, len, "\004%.2fdB", v);
+ chsnprintf(buf, len, S_DELTA "%.2fdB", v);
  break;
  case TRC_PHASE:
  v = phase(coeff) - phase(coeff_ref);
- chsnprintf(buf, len, "\004%.2f" S_DEGREE, v);
+ chsnprintf(buf, len, S_DELTA "%.2f" S_DEGREE, v);
  break;
  case TRC_DELAY:
  v = groupdelay_from_array(index, array) - groupdelay_from_array(index_ref, array);
  string_value_with_prefix(buf, len, v, 's');
  break;
  case TRC_LINEAR:
  v = linear(coeff) - linear(coeff_ref);
- chsnprintf(buf, len, "\004%.2f", v);
+ chsnprintf(buf, len, S_DELTA "%.2f", v);
  break;
  case TRC_SWR:
  v = swr(coeff) - swr(coeff_ref);
- chsnprintf(buf, len, "\004%.2f", v);
+ chsnprintf(buf, len, S_DELTA "%.2f", v);
  break;
  case TRC_SMITH:
  format_smith_value(buf, len, coeff, frequencies[index]);
  break;
  case TRC_REAL:
- chsnprintf(buf, len, "\004%.2f", coeff[0] - coeff_ref[0]);
+ chsnprintf(buf, len, S_DELTA "%.2f", coeff[0] - coeff_ref[0]);
  break;
  case TRC_IMAG:
- chsnprintf(buf, len, "\004%.2fj", coeff[1] - coeff_ref[1]);
+ chsnprintf(buf, len, S_DELTA "%.2fj", coeff[1] - coeff_ref[1]);
  break;
  case TRC_R:
  gamma2resistance(buf, len, coeff);
@@ -1594,7 +1594,7 @@ cell_draw_marker_info(int m, int n, int w, int h)
  int32_t freq = frequencies[markers[mk].index];
  if (uistat.marker_delta && mk != active_marker) {
  freq -= frequencies[markers[active_marker].index];
- frequency_string_short(buf, sizeof buf, freq, '\004');
+ frequency_string_short(buf, sizeof buf, freq, S_DELTA[0]);
  } else {
  frequency_string_short(buf, sizeof buf, freq, 0);
  }
@@ -1615,7 +1615,8 @@ cell_draw_marker_info(int m, int n, int w, int h)
  int ypos = 1 + (j/2)*7;
  xpos -= m * CELLWIDTH -CELLOFFSETX;
  ypos -= n * CELLHEIGHT;
- chsnprintf(buf, sizeof buf, "\004%d:", previous_marker+1);
+ strcpy(buf, S_DELTA "1:");
+ buf[1] += previous_marker;
  cell_drawstring_5x7(w, h, buf, xpos, ypos, 0xffff);
  xpos += 19;
  if ((domain_mode & DOMAIN_MODE) == DOMAIN_FREQ) {
@@ -1655,7 +1656,8 @@ cell_draw_marker_info(int m, int n, int w, int h)
  int ypos = 1 + (j/2)*7;
  xpos -= m * CELLWIDTH -CELLOFFSETX;
  ypos -= n * CELLHEIGHT;
- chsnprintf(buf, sizeof buf, "%d:", active_marker + 1);
+ strcpy(buf, "1:");
+ buf[0] += active_marker;
  xpos += 5;
  cell_drawstring_invert_5x7(w, h, buf, xpos, ypos, 0xffff, uistat.lever_mode == LM_MARKER);
  xpos += 14;