feat(ui-new): Tools > Satellites -- sky plot and signal bars on the 128x64 OLED

Two views, swapped with left / right: a polar sky plot (filled = used in the fix, hollow = tracked, a pixel = no signal) beside fix, used / in view, HDOP, PDOP and time to first fix; and a signal bar per satellite (used first, a dotted 30 dB-Hz line) under per-constellation counts. The GPS stays awake while it's open. Data from GpsSky (-D GPS_SKYVIEW, now on the L1 solo build). The simulator's made-up sky moves from the L2's GpsScreen into helpers/sensors/GpsSkySim.h, so both sims show it. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-09 03:06:39 +00:00 · 2026-09-28 16:33:41 +02:00
parent e82cedaf23
commit 95c4c093f0
8 changed files with 302 additions and 61 deletions
@@ -44,62 +44,7 @@ static uint32_t snrColor(int snr) {
 }

 #if defined(SIM_PLATFORM) && defined(GPS_SKYVIEW)
-// The sim has no receiver: a made-up sky, sent through the real parser as
-// NMEA once a second. The fix comes 20 s after the screen first asks.
-static GpsSky s_sim_sky;
-static void simSentence(const char* body) {
-  uint8_t cs = 0;
-  for (const char* p = body; *p; p++) cs ^= (uint8_t)*p;
-  char line[120];
-  snprintf(line, sizeof(line), "$%s*%02X\r\n", body, cs);
-  for (const char* p = line; *p; p++) s_sim_sky.feed(*p);
-}
-static void simFeed() {
-  static uint32_t s_next = 0, s_t0 = 0;
-  uint32_t now = millis();
-  if (!s_t0) s_t0 = now;
-  if ((int32_t)(now - s_next) < 0) return;
-  s_next = now + 1000;
-  struct SimSat { const char* talker; int prn, elev, az, snr; };
-  static const SimSat SATS[] = {
-    { "GP", 2, 72, 40, 44 }, { "GP", 5, 48, 120, 41 }, { "GP", 12, 31, 205, 36 }, { "GP", 15, 18, 290, 27 },
-    { "GP", 20, 63, 310, 43 }, { "GP", 25, 9, 75, 18 }, { "GP", 29, 22, 160, 31 }, { "GP", 44, 30, 190, 33 },
-    { "BD", 7, 55, 250, 38 }, { "BD", 10, 40, 20, 35 }, { "BD", 23, 12, 140, -1 }, { "BD", 37, 67, 95, 42 },
-    { "GL", 71, 35, 330, 29 }, { "GL", 72, 50, 260, 34 }, { "GL", 80, 6, 30, -1 },
-  };
-  const int N = sizeof(SATS) / sizeof(SATS[0]);
-  float t = (now - s_t0) / 1000.0f;
-  bool fix = t > 20;
-  char b[110];
-  for (const char* talker : { "GP", "BD", "GL" }) {
-    const SimSat* mine[8];
-    int k = 0;
-    for (int i = 0; i < N; i++) if (!strcmp(SATS[i].talker, talker)) mine[k++] = &SATS[i];
-    int msgs = (k + 3) / 4;
-    for (int m = 0; m < msgs; m++) {
-      int o = snprintf(b, sizeof(b), "%sGSV,%d,%d,%02d", talker, msgs, m + 1, k);
-      for (int j = m * 4; j < k && j < m * 4 + 4; j++) {
-        const SimSat& s = *mine[j];
-        int az = ((int)(s.az + t / 6) % 360);
-        int snr = s.snr < 0 ? -1 : s.snr - (fix ? 0 : 8) + (int)(3 * sinf(t / 3 + s.prn));
-        if (snr >= 0) o += snprintf(b + o, sizeof(b) - o, ",%02d,%02d,%03d,%02d", s.prn, s.elev, az, snr);
-        else o += snprintf(b + o, sizeof(b) - o, ",%02d,%02d,%03d,", s.prn, s.elev, az);
-      }
-      simSentence(b);
-    }
-  }
-  if (fix) {
-    simSentence("GNGSA,A,3,02,05,12,15,20,29,,,,,,,1.6,0.9,1.3,1");
-    simSentence("GNGSA,A,3,07,10,37,,,,,,,,,,1.6,0.9,1.3,4");
-    simSentence("GNGSA,A,3,72,,,,,,,,,,,,1.6,0.9,1.3,2");
-    simSentence("GNGGA,120000.00,5213.0000,N,02100.0000,E,1,10,0.9,112.4,M,34.5,M,,");
-    simSentence("GNRMC,120000.00,A,5213.0000,N,02100.0000,E,0.4,87.0,260926,,,A");
-  } else {
-    simSentence("GNGSA,A,1,,,,,,,,,,,,,99.9,99.9,99.9,1");
-    simSentence("GNGGA,120000.00,,,,,0,00,99.9,,,,,,");
-    simSentence("GNRMC,120000.00,V,,,,,,,260926,,,N");
-  }
-}
+  #include <helpers/sensors/GpsSkySim.h>
 #endif

 // The receiver's data, or nullptr on a board without the parser.
@@ -107,8 +52,7 @@ static GpsSky* sky() {
 #if defined(SEEED_WIO_TRACKER_L2) && defined(GPS_SKYVIEW)
  return &gps.sky();
 #elif defined(SIM_PLATFORM) && defined(GPS_SKYVIEW)
-  simFeed();
-  return &s_sim_sky;
+  return gpsSkySim();
 #else
  return nullptr;
 #endif
@@ -0,0 +1,212 @@
+#pragma once
+// Tools › Satellites (-D GPS_SKYVIEW): what the GPS receiver sees, in two
+// views swapped with left / right (or Enter):
+//   Sky    -- a polar plot (the rim is the horizon, the centre straight up,
+//             north at the top): a filled dot is a satellite the fix uses, a
+//             hollow one is tracked but unused, a single pixel is in view with
+//             no signal. Beside it: fix, used / in view, HDOP, PDOP and the
+//             time to first fix (or how long it's been looking).
+//   Signal -- a bar per satellite, its height the signal (C/N0, 50 dB-Hz =
+//             full), filled when used; a dotted line marks 30 dB-Hz (good).
+//             The top line counts used / in view per constellation.
+//
+// The data is helpers/sensors/GpsSky.h, fed the board's NMEA by
+// MicroNMEALocationProvider (a made-up sky in the simulator: GpsSkySim.h).
+// The GPS is kept awake while the screen is open (UITask's keep-awake list).
+
+#include <math.h>
+#include <helpers/sensors/GpsSky.h>
+#ifdef SIM_PLATFORM
+  #include <helpers/sensors/GpsSkySim.h>
+#else
+  #include <helpers/sensors/MicroNMEALocationProvider.h>
+#endif
+#include "icons.h"   // miniIconScale()
+
+class SatellitesScreen : public UIScreen {
+  UITask* _task;
+  bool _signal = false;   // false: the sky view
+
+  // The board's location provider is a MicroNMEALocationProvider wherever
+  // GPS_SKYVIEW is set (the flag's contract, as on the L2).
+  static GpsSky* sky() {
+#ifdef SIM_PLATFORM
+    return gpsSkySim();
+#else
+    LocationProvider* p = sensors.getLocationProvider();
+    return p ? &((MicroNMEALocationProvider*)p)->sky() : nullptr;
+#endif
+  }
+
+  static void dot(DisplayDriver& d, int x, int y) { d.fillRect(x, y, 1, 1); }
+
+  // Midpoint circle; `step` > 1 dots it (every step-th point of each octant).
+  static void circle(DisplayDriver& d, int cx, int cy, int r, int step = 1) {
+    int x = r, y = 0, err = 1 - r, i = 0;
+    while (x >= y) {
+      if (i++ % step == 0) {
+        dot(d, cx + x, cy + y); dot(d, cx - x, cy + y); dot(d, cx + x, cy - y); dot(d, cx - x, cy - y);
+        dot(d, cx + y, cy + x); dot(d, cx - y, cy + x); dot(d, cx + y, cy - x); dot(d, cx - y, cy - x);
+      }
+      y++;
+      if (err < 0) err += 2 * y + 1;
+      else { x--; err += 2 * (y - x) + 1; }
+    }
+  }
+
+  static int usedCount(const GpsSky& g) {
+    int n = 0;
+    for (int i = 0; i < g.count; i++) if (g.used(g.sats[i])) n++;
+    return n;
+  }
+
+  void renderSky(DisplayDriver& d, GpsSky& g, int top) {
+    const int lh = d.getLineHeight();
+    const int cw = d.getCharWidth();
+    const int s = miniIconScale(d);
+    const int r = (d.height() - 1 - top) / 2 - 1;
+    const int cx = r + 1, cy = top + r + 1;
+
+    circle(d, cx, cy, r);            // the horizon
+    circle(d, cx, cy, r / 2, 2);     // 45 degrees up, dotted
+    dot(d, cx, cy);                  // straight up
+    d.setColor(DisplayDriver::DARK);   // north, on a gap in the rim
+    d.fillRect(cx - cw / 2 - 1, cy - r - lh / 2, cw + 2, lh);
+    d.setColor(DisplayDriver::LIGHT);
+    d.setCursor(cx - cw / 2, cy - r - lh / 2);
+    d.print("N");
+
+    for (int pass = 0; pass < 2; pass++) {   // the used ones last, on top
+      for (int i = 0; i < g.count; i++) {
+        const GpsSky::Sat& sat = g.sats[i];
+        bool used = g.used(sat);
+        if (sat.elev < 0 || sat.azim < 0 || used != (pass == 1)) continue;
+        float rr = r * (90 - sat.elev) / 90.0f;
+        float a = sat.azim * (float)M_PI / 180.0f;
+        int x = cx + (int)lroundf(rr * sinf(a)), y = cy - (int)lroundf(rr * cosf(a));
+        if (used) {
+          d.fillRect(x - s, y - s, 2 * s + 1, 2 * s + 1);
+        } else if (sat.snr >= 0) {
+          d.setColor(DisplayDriver::DARK);   // clear inside, over a ring
+          d.fillRect(x - s, y - s, 2 * s + 1, 2 * s + 1);
+          d.setColor(DisplayDriver::LIGHT);
+          d.drawRect(x - s, y - s, 2 * s + 1, 2 * s + 1);
+        } else {
+          dot(d, x, y);
+        }
+      }
+    }
+
+    // The numbers, right of the plot.
+    const int x0 = 2 * r + 6, step = lh + 1;
+    int y = top;
+    char buf[24];
+    d.setCursor(x0, y);
+    d.print(g.fix_mode == 3 ? "3D fix" : g.hasFix() ? "2D fix" : "No fix");
+    y += step;
+    snprintf(buf, sizeof(buf), "Sats %d/%d", usedCount(g), g.count);
+    d.setCursor(x0, y); d.print(buf);
+    y += step;
+    if (g.hdop > 0 && g.hdop < 99) snprintf(buf, sizeof(buf), "HDOP %.1f", g.hdop);
+    else snprintf(buf, sizeof(buf), "HDOP -");
+    d.setCursor(x0, y); d.print(buf);
+    y += step;
+    if (g.pdop > 0 && g.pdop < 99) snprintf(buf, sizeof(buf), "PDOP %.1f", g.pdop);
+    else snprintf(buf, sizeof(buf), "PDOP -");
+    d.setCursor(x0, y); d.print(buf);
+    y += step;
+    if (g.ttff_ms) snprintf(buf, sizeof(buf), "TTFF %lus", (unsigned long)(g.ttff_ms / 1000));
+    else if (g.start_ms) snprintf(buf, sizeof(buf), "Wait %lus", (unsigned long)((millis() - g.start_ms) / 1000));
+    else buf[0] = 0;
+    d.setCursor(x0, y); d.print(buf);
+  }
+
+  void renderSignal(DisplayDriver& d, GpsSky& g, int top) {
+    const int lh = d.getLineHeight();
+    const int W = d.width();
+
+    // Used / in view per constellation, the ones with any in view.
+    char line[40];
+    int o = 0;
+    for (uint8_t sys = 0; sys < GpsSky::SYS_COUNT && o < (int)sizeof(line) - 8; sys++) {
+      int seen = 0, used = 0;
+      for (int i = 0; i < g.count; i++) {
+        if (g.sats[i].sys != sys) continue;
+        seen++;
+        if (g.used(g.sats[i])) used++;
+      }
+      if (seen) o += snprintf(line + o, sizeof(line) - o, "%s%c%d/%d", o ? " " : "", GpsSky::sysLetter(sys), used, seen);
+    }
+    d.drawTextEllipsized(0, top, W, o ? line : "None in view");
+
+    // Used first, then the strongest.
+    int idx[GpsSky::MAX_SATS];
+    int n = g.count;
+    for (int i = 0; i < n; i++) idx[i] = i;
+    auto key = [&](int i) { return (g.used(g.sats[i]) ? 100 : 0) + g.sats[i].snr; };
+    for (int i = 1; i < n; i++) {   // insertion sort, <= 64
+      int v = idx[i], j = i - 1;
+      while (j >= 0 && key(idx[j]) < key(v)) { idx[j + 1] = idx[j]; j--; }
+      idx[j + 1] = v;
+    }
+    int fit = (W + 1) / 3;   // bars at least 2 px wide, 1 px apart
+    if (n > fit) n = fit;
+    if (!n) return;
+    int bw = (W + 1) / n - 1;
+    if (bw > 8) bw = 8;
+
+    const int y0 = top + lh + 3, y1 = d.height() - 1, H = y1 - y0;
+    for (int x = 0; x < W; x += 3) dot(d, x, y1 - H * 30 / 50);   // 30 dB-Hz
+    for (int k = 0; k < n; k++) {
+      const GpsSky::Sat& sat = g.sats[idx[k]];
+      int x = k * (bw + 1);
+      int snr = sat.snr > 50 ? 50 : sat.snr;
+      int h = snr < 0 ? 1 : (H * snr / 50 > 2 ? H * snr / 50 : 2);
+      if (g.used(sat) || h <= 2) d.fillRect(x, y1 - h + 1, bw, h);
+      else {
+        d.setColor(DisplayDriver::DARK);   // over the dotted line
+        d.fillRect(x, y1 - h + 1, bw, h);
+        d.setColor(DisplayDriver::LIGHT);
+        d.drawRect(x, y1 - h + 1, bw, h);
+      }
+    }
+  }
+
+public:
+  SatellitesScreen(UITask* task) : _task(task) {}
+  void onShow() override {}
+
+  int render(DisplayDriver& display) override {
+    display.setTextSize(1);
+    display.setColor(DisplayDriver::LIGHT);
+    display.drawCenteredHeader(_signal ? "SIGNAL" : "SKY");
+    display.drawTextRightAlign(display.width() - 1, 0, _signal ? "2/2" : "1/2");
+    const int top = display.listStart();
+    const int cx = display.width() / 2, lh = display.getLineHeight();
+
+    GpsSky* g = sky();
+    if (!g) {
+      display.drawTextCentered(cx, top + lh, "No GPS data");
+      return 1000;
+    }
+    g->expire();
+    if (!g->sentences || millis() - g->last_ms > 5000) {
+      bool on = _task->getGPSState();
+      display.drawTextCentered(cx, top + lh, on ? "Waiting for GPS..." : "GPS is off");
+      if (!on) display.drawTextCentered(cx, top + 2 * lh + 2, "Home > GPS page");
+      return 1000;
+    }
+    if (_signal) renderSignal(display, *g, top);
+    else renderSky(display, *g, top);
+    return 1000;
+  }
+
+  bool handleInput(char c) override {
+    if (c == KEY_CANCEL) { _task->gotoToolsScreen(); return true; }
+    if (c == KEY_LEFT || c == KEY_RIGHT || c == KEY_ENTER || c == KEY_NEXT || c == KEY_PREV) {
+      _signal = !_signal;
+      return true;
+    }
+    return true;
+  }
+};
@@ -13,7 +13,7 @@ class ToolsScreen : public UIScreen {
  UITask* _task;

  enum Action {
-    ACT_NEARBY, ACT_LIVESHARE, ACT_TRAIL, ACT_LOCATOR, ACT_COMPASS,
+    ACT_NEARBY, ACT_LIVESHARE, ACT_TRAIL, ACT_LOCATOR, ACT_COMPASS, ACT_SATELLITES,
    ACT_BOT, ACT_AUTOADVERT, ACT_REPEATER, ACT_ADMIN,
    ACT_CLOCK, ACT_RINGTONE, ACT_DIAGNOSTICS
 #if defined(PIN_GPIO1)
@@ -54,6 +54,7 @@ class ToolsScreen : public UIScreen {
      case ACT_TRAIL:       _task->gotoTrailScreen();       break;
      case ACT_LOCATOR:     _task->gotoLocatorScreen();     break;
      case ACT_COMPASS:     _task->gotoCompassScreen();     break;
+      case ACT_SATELLITES:  _task->gotoSatellitesScreen();  break;
      case ACT_BOT:         _task->gotoBotScreen();         break;
      case ACT_AUTOADVERT:  _task->gotoAutoAdvertScreen();  break;
      case ACT_REPEATER:    _task->gotoRepeaterScreen();    break;
@@ -128,6 +129,9 @@ const ToolsScreen::Tool ToolsScreen::LOCATION_TOOLS[] = {
  { "Trail",        &ICON_TRAIL,        ACT_TRAIL },
  { "Locator",    &ICON_MAP_WAYPOINT, ACT_LOCATOR },
  { "Compass",      &ICON_MAP_NORTH,    ACT_COMPASS },
+#if ENV_INCLUDE_GPS == 1 && defined(GPS_SKYVIEW)
+  { "Satellites",   &ICON_GPS,          ACT_SATELLITES },
+#endif
 };
 const ToolsScreen::Tool ToolsScreen::COMMS_TOOLS[] = {
  { "Remote Bot",     &ICON_BOT,      ACT_BOT },
@@ -144,7 +148,7 @@ const ToolsScreen::Tool ToolsScreen::SYSTEM_TOOLS[] = {
 #endif
 };
 const ToolsScreen::Section ToolsScreen::SECTIONS[] = {
-  { "Location", &ICON_MAP_CONTACT, LOCATION_TOOLS, 5 },
+  { "Location", &ICON_MAP_CONTACT, LOCATION_TOOLS, (uint8_t)(sizeof(LOCATION_TOOLS)/sizeof(LOCATION_TOOLS[0])) },
  { "Comms",    &ICON_ADVERT,      COMMS_TOOLS,    4 },
  { "System",   &ICON_GEAR,        SYSTEM_TOOLS,   (uint8_t)(sizeof(SYSTEM_TOOLS)/sizeof(SYSTEM_TOOLS[0])) },
 };
@@ -178,6 +178,9 @@ static const int QUICK_MSGS_MAX = 10;
 #include "LocatorScreen.h"
 #include "TrailScreen.h"
 #include "CompassScreen.h"
+#if ENV_INCLUDE_GPS == 1 && defined(GPS_SKYVIEW)
+  #include "SatellitesScreen.h"
+#endif
 #include "DiagnosticsScreen.h"
 #include "RepeaterScreen.h"
 #if defined(PIN_GPIO1)
@@ -1623,6 +1626,9 @@ void UITask::begin(DisplayDriver* display, SensorManager* sensors, NodePrefs* no
  locator_screen  = new LocatorScreen(this, node_prefs);
  trail_screen       = new TrailScreen(this, &_core->trail.store());
  compass_screen     = new CompassScreen(this);
+#if ENV_INCLUDE_GPS == 1 && defined(GPS_SKYVIEW)
+  satellites_screen  = new SatellitesScreen(this);
+#endif
  diag_screen        = new DiagnosticsScreen(this);
  repeater_screen    = new RepeaterScreen(this);
  clock_tools        = new ClockToolsScreen(this, node_prefs);
@@ -1654,6 +1660,7 @@ void UITask::openAdminFor(const ContactInfo& ci, bool from_picker) {
 void UITask::gotoDashboardConfig() { setCurrScreen(dashboard_config); }
 void UITask::gotoTrailScreen()     { setCurrScreen(trail_screen); }
 void UITask::gotoCompassScreen()   { setCurrScreen(compass_screen); }
+void UITask::gotoSatellitesScreen() { if (satellites_screen) setCurrScreen(satellites_screen); }
 void UITask::gotoDiagnosticsScreen() { setCurrScreen(diag_screen); }
 void UITask::gotoRepeaterScreen()  { setCurrScreen(repeater_screen); }
 void UITask::gotoClockTools()      { setCurrScreen(clock_tools); }
@@ -2813,6 +2820,7 @@ void UITask::loop() {
        || (_node_prefs && _node_prefs->loc_share_enabled)
        || (_node_prefs && _node_prefs->locator_enabled && _node_prefs->locator_has_target)
        || curr == compass_screen
+        || (satellites_screen && curr == satellites_screen)
        || (curr == nearby_screen && ((NearbyScreen*)nearby_screen)->isNavigating())
        || (curr == trail_screen && ((TrailScreen*)trail_screen)->wpNeedsLiveGps())
        || (curr == messages_screen && ((MessagesScreen*)messages_screen)->navActive())
@@ -112,6 +112,7 @@ class UITask : public UITaskBase, public UiCoreHost {
  UIScreen* locator_screen = nullptr;
  UIScreen* trail_screen = nullptr;
  UIScreen* compass_screen = nullptr;
+  UIScreen* satellites_screen = nullptr;   // Tools > Satellites (-D GPS_SKYVIEW)
  UIScreen* diag_screen = nullptr;
  UIScreen* repeater_screen = nullptr;
  UIScreen* clock_tools = nullptr;
@@ -316,6 +317,7 @@ public:
  void gotoTrailScreen();
  void gotoMapScreen();   // opens the Trail screen directly in its Map view
  void gotoCompassScreen();
+  void gotoSatellitesScreen();
  void gotoDiagnosticsScreen();
  void gotoRepeaterScreen();
  void gotoGpioScreen();   // no-op on boards without user GPIO pins (see PIN_GPIO1)
@@ -15,5 +15,6 @@ build_flags = ${WioTrackerL1CompanionDual.build_flags}
  -D UI_HAS_JOYSTICK_UPDOWN=1
  -D ENABLE_SCREENSHOT
  -D DUAL_SERIAL=1
+  -D GPS_SKYVIEW   ; Tools > Satellites (helpers/sensors/GpsSky.h)
  -Os
 extra_scripts = post:create-uf2.py
@@ -0,0 +1,69 @@
+#pragma once
+// The browser simulator has no GPS receiver: a made-up sky (GPS, BeiDou and
+// GLONASS satellites drifting slowly round), sent through the real GpsSky
+// parser as NMEA once a second. The fix comes 20 s after the first ask.
+// Both UIs' satellite screens read it through gpsSkySim().
+
+#include "GpsSky.h"
+#include <math.h>
+#include <stdio.h>
+
+static GpsSky s_gps_sim_sky;
+static void gpsSimSentence(const char* body) {
+  uint8_t cs = 0;
+  for (const char* p = body; *p; p++) cs ^= (uint8_t)*p;
+  char line[120];
+  snprintf(line, sizeof(line), "$%s*%02X\r\n", body, cs);
+  for (const char* p = line; *p; p++) s_gps_sim_sky.feed(*p);
+}
+static void gpsSimFeed() {
+  static uint32_t s_next = 0, s_t0 = 0;
+  uint32_t now = millis();
+  if (!s_t0) s_t0 = now;
+  if ((int32_t)(now - s_next) < 0) return;
+  s_next = now + 1000;
+  struct SimSat { const char* talker; int prn, elev, az, snr; };
+  static const SimSat SATS[] = {
+    { "GP", 2, 72, 40, 44 }, { "GP", 5, 48, 120, 41 }, { "GP", 12, 31, 205, 36 }, { "GP", 15, 18, 290, 27 },
+    { "GP", 20, 63, 310, 43 }, { "GP", 25, 9, 75, 18 }, { "GP", 29, 22, 160, 31 }, { "GP", 44, 30, 190, 33 },
+    { "BD", 7, 55, 250, 38 }, { "BD", 10, 40, 20, 35 }, { "BD", 23, 12, 140, -1 }, { "BD", 37, 67, 95, 42 },
+    { "GL", 71, 35, 330, 29 }, { "GL", 72, 50, 260, 34 }, { "GL", 80, 6, 30, -1 },
+  };
+  const int N = sizeof(SATS) / sizeof(SATS[0]);
+  float t = (now - s_t0) / 1000.0f;
+  bool fix = t > 20;
+  char b[110];
+  for (const char* talker : { "GP", "BD", "GL" }) {
+    const SimSat* mine[8];
+    int k = 0;
+    for (int i = 0; i < N; i++) if (!strcmp(SATS[i].talker, talker)) mine[k++] = &SATS[i];
+    int msgs = (k + 3) / 4;
+    for (int m = 0; m < msgs; m++) {
+      int o = snprintf(b, sizeof(b), "%sGSV,%d,%d,%02d", talker, msgs, m + 1, k);
+      for (int j = m * 4; j < k && j < m * 4 + 4; j++) {
+        const SimSat& s = *mine[j];
+        int az = ((int)(s.az + t / 6) % 360);
+        int snr = s.snr < 0 ? -1 : s.snr - (fix ? 0 : 8) + (int)(3 * sinf(t / 3 + s.prn));
+        if (snr >= 0) o += snprintf(b + o, sizeof(b) - o, ",%02d,%02d,%03d,%02d", s.prn, s.elev, az, snr);
+        else o += snprintf(b + o, sizeof(b) - o, ",%02d,%02d,%03d,", s.prn, s.elev, az);
+      }
+      gpsSimSentence(b);
+    }
+  }
+  if (fix) {
+    gpsSimSentence("GNGSA,A,3,02,05,12,15,20,29,,,,,,,1.6,0.9,1.3,1");
+    gpsSimSentence("GNGSA,A,3,07,10,37,,,,,,,,,,1.6,0.9,1.3,4");
+    gpsSimSentence("GNGSA,A,3,72,,,,,,,,,,,,1.6,0.9,1.3,2");
+    gpsSimSentence("GNGGA,120000.00,5213.0000,N,02100.0000,E,1,10,0.9,112.4,M,34.5,M,,");
+    gpsSimSentence("GNRMC,120000.00,A,5213.0000,N,02100.0000,E,0.4,87.0,260926,,,A");
+  } else {
+    gpsSimSentence("GNGSA,A,1,,,,,,,,,,,,,99.9,99.9,99.9,1");
+    gpsSimSentence("GNGGA,120000.00,,,,,0,00,99.9,,,,,,");
+    gpsSimSentence("GNRMC,120000.00,V,,,,,,,260926,,,N");
+  }
+}
+
+static GpsSky* gpsSkySim() {
+  gpsSimFeed();
+  return &s_gps_sim_sky;
+}
@@ -159,6 +159,7 @@ DEFINES=(
  # surface them as on-device pages.
  -DENV_INCLUDE_GPS=1
  -DUI_SENSORS_PAGE=1
+  -DGPS_SKYVIEW   # satellite screens (GpsSkySim.h feeds a made-up sky)
 )

 # The on-device splash's "Solo <version>" bar shows FIRMWARE_VERSION. Without
@@ -184,7 +185,7 @@ if [ "$SIM_UI" = "lvgl" ]; then
  done
  # The L2's PSRAM-sized limits (solo/wio-tracker-l2/platformio.ini).
  DEFINES=("${kept[@]}" -DDISPLAY_CLASS=SimLcdDisplay -DMAX_GROUP_CHANNELS=40 -DUI_ZOOM=1 -DLV_CONF_INCLUDE_SIMPLE
-           -DTRAIL_CAPACITY=4096 -DWAYPOINT_CAPACITY=64 -DHIST_CH_MAX=256 -DHIST_DM_MAX=128 -DNEARBY_MAX=64 -DHIST_ARCHIVE -DGPS_SKYVIEW)
+           -DTRAIL_CAPACITY=4096 -DWAYPOINT_CAPACITY=64 -DHIST_CH_MAX=256 -DHIST_DM_MAX=128 -DNEARBY_MAX=64 -DHIST_ARCHIVE)
  INCLUDES+=("-I$LVGL_DIR")
  LINK_EXTRA=(-sFETCH=1)   # map downloads (LvglPort.h) go through emscripten_fetch
 fi