fix: overflow, stale aircraft age-out, dead code, per-frame redundancies

include/config.h

@@ -50,8 +50,6 @@ constexpr double kDefaultRadarLon = 4.9041;
 
 /** Poll adsb.fi (API public limit: 1 req/s). */
 constexpr unsigned long kAdsbFetchIntervalMs = 3000;
-/** Legacy scale unused — fetch uses radar::fetchRadiusKm() to screen edge. */
-constexpr float kAdsbFetchRadiusScale = 1.0f;
 /** false = hide aircraft with alt_baro "ground"; true = show them too. */
 constexpr bool kAdsbShowGroundAircraft = false;
 

include/services/adsb_client.h

@@ -27,4 +27,7 @@ void setPollFn(PollFn fn);
 /** Fetch aircraft within fetch_radius_km of center_lat/lon from adsb.fi. */
 bool fetchUpdate(double center_lat, double center_lon, float fetch_radius_km);
 
+/** millis() of the last successful fetch (0 = never). */
+unsigned long lastSuccessMs();
+
 }  // namespace services::adsb

include/ui/radar_range.h

@@ -39,7 +39,6 @@ void rangeInit();
 /** Cycle preset and save to flash. */
 void rangeNext();
 const RangePreset& rangeCurrent();
-uint8_t rangeIndex();
 /** ADSB fetch radius (km): scaled to screen edge so beyond-ring dots have data. */
 float fetchRadiusKm();
 

src/services/adsb_client.cpp

@@ -21,6 +21,7 @@ constexpr unsigned long kRequestTimeoutMs = 10000;
 Aircraft s_aircraft[kMaxAircraft];
 size_t s_aircraft_count = 0;
 PollFn s_poll_fn = nullptr;
+unsigned long s_last_success_ms = 0;
 
 void pollNetwork() {
   if (s_poll_fn != nullptr) {
@@ -30,8 +31,8 @@ void pollNetwork() {
 
 int performGetWithPoll(HTTPClient& http) {
   http.setConnectTimeout(kConnectAttemptMs);
-  const unsigned long deadline = millis() + kRequestTimeoutMs;
-  while (millis() < deadline) {
+  const unsigned long start = millis();
+  while (millis() - start < kRequestTimeoutMs) {
     pollNetwork();
     const int code = http.GET();
     if (code > 0) {
@@ -58,8 +59,8 @@ bool readResponseBodyWithPoll(HTTPClient& http, String& payload) {
   }
 
   uint8_t buffer[512];
-  const unsigned long deadline = millis() + kRequestTimeoutMs;
-  while (millis() < deadline) {
+  const unsigned long start = millis();
+  while (millis() - start < kRequestTimeoutMs) {
     pollNetwork();
     const int available = stream->available();
     if (available > 0) {
@@ -276,8 +277,11 @@ bool fetchUpdate(double center_lat, double center_lon, float fetch_radius_km) {
   }
 
   s_aircraft_count = n;
+  s_last_success_ms = millis();
   Serial.printf("adsb: %u aircraft\n", static_cast<unsigned>(n));
   return true;
 }
 
+unsigned long lastSuccessMs() { return s_last_success_ms; }
+
 }  // namespace services::adsb

src/ui/radar_display.cpp

@@ -46,9 +46,6 @@ const lgfx::GFXfont* s_tag_gfx = &fonts::FreeSansBold12pt7b;
 bool s_tag_label_metrics_ready = false;
 bool s_tag_use_vlw = false;
 
-int s_scale_label_max_w = 0;
-int s_scale_label_h = 0;
-
 lgfx::LovyanGFX* s_draw = &tft;
 LGFX_Sprite s_frame(&tft);
 bool s_frame_ready = false;
@@ -135,21 +132,6 @@ void initLabelMetrics() {
     s_scale_use_vlw = false;
   }
 
-  applyScaleStyle();
-  s_scale_label_h = tft.fontHeight();
-  s_scale_label_max_w = 0;
-  char label[12];
-  for (size_t i = 0; i < radar::kRangePresetCount; ++i) {
-    for (bool miles : {false, true}) {
-      radar::formatRing3Label(label, sizeof(label), radar::kRangePresets[i].ring3_km,
-                              miles);
-      const int w = tft.textWidth(label);
-      if (w > s_scale_label_max_w) {
-        s_scale_label_max_w = w;
-      }
-    }
-  }
-
   s_label_metrics_ready = true;
 }
 
@@ -382,7 +364,6 @@ void applyTagStyle() {
 }
 
 int measureTagBlockWidth(const services::adsb::Aircraft& plane) {
-  applyTagStyle();
   int max_w = 0;
   if (plane.callsign[0] != '\0') {
     const int w = s_draw->textWidth(plane.callsign);
@@ -406,9 +387,6 @@ int measureTagBlockWidth(const services::adsb::Aircraft& plane) {
 }
 
 void drawAircraftTag(int x, int y, const services::adsb::Aircraft& plane) {
-  initTagLabelMetrics();
-  applyTagStyle();
-
   const int line_h = s_draw->fontHeight();
   const int block_w = measureTagBlockWidth(plane);
   const int block_h = line_h * 3;
@@ -488,7 +466,13 @@ void sortBeyondDotsFarFirst(BeyondDotDrawItem* items, size_t count) {
 void drawAircraft() {
   initLabelMetrics();
 
-  const size_t n = services::adsb::aircraftCount();
+  // Stale data (no successful fetch recently) shows an empty scope rather
+  // than aircraft frozen at their last known positions.
+  constexpr unsigned long kAircraftStaleAfterMs = 15000;
+  const size_t n =
+      (millis() - services::adsb::lastSuccessMs() > kAircraftStaleAfterMs)
+          ? 0
+          : services::adsb::aircraftCount();
   const services::adsb::Aircraft* planes = services::adsb::aircraftList();
 
   AircraftDrawItem items[services::adsb::kMaxAircraft];
@@ -531,6 +515,8 @@ void drawAircraft() {
     drawBeyondRingDot(dots[d].x, dots[d].y);
   }
 
+  initTagLabelMetrics();
+  applyTagStyle();  // once per frame; tag text metrics stay valid below
   sortDrawItemsFarFirst(items, draw_count);
   for (size_t d = 0; d < draw_count; ++d) {
     const size_t i = items[d].index;
@@ -651,7 +637,6 @@ void drawStaticGrid(Gfx& gfx) {
   gfx.fillScreen(radar::kColorBackground);
   drawRings(cx, cy, grid_r);
   drawCrosshairs(cx, cy, grid_r, radar::kColorGrid);
-  initPalette();
   runway::drawLargeAirportRunways(gfx);
   drawCenterDot(cx, cy);
   drawCardinalLabels();

src/ui/radar_range.cpp

@@ -80,8 +80,6 @@ void rangeNext() {
 
 const RangePreset& rangeCurrent() { return kRangePresets[s_range_index]; }
 
-uint8_t rangeIndex() { return s_range_index; }
-
 float fetchRadiusKm() {
   const float outer_km = rangeCurrent().outer_km;
   const float screen_r_px =

src/ui/runway_overlay.cpp

@@ -145,20 +145,21 @@ bool segmentIntersectsDisc(int x0, int y0, int x1, int y1) {
   const int dy = y1 - y0;
   const int fx = x0 - cx;
   const int fy = y0 - cy;
-  const int a = dx * dx + dy * dy;
-  if (a == 0) {
+  const float a = static_cast<float>(dx) * dx + static_cast<float>(dy) * dy;
+  if (a == 0.0f) {
     return false;
   }
-  const int b = 2 * (fx * dx + fy * dy);
-  const int c = fx * fx + fy * fy - r_sq;
-  int disc = b * b - 4 * a * c;
-  if (disc < 0) {
+  const float b = 2.0f * (static_cast<float>(fx) * dx + static_cast<float>(fy) * dy);
+  const float c = static_cast<float>(fx) * fx + static_cast<float>(fy) * fy -
+                  static_cast<float>(r_sq);
+  const float disc = b * b - 4.0f * a * c;
+  if (disc < 0.0f) {
     return false;
   }
-  disc = static_cast<int>(sqrtf(static_cast<float>(disc)));
-  const float inv2a = 1.0f / (2.0f * static_cast<float>(a));
-  const float t0 = (-static_cast<float>(b) - disc) * inv2a;
-  const float t1 = (-static_cast<float>(b) + disc) * inv2a;
+  const float sq = sqrtf(disc);
+  const float inv2a = 1.0f / (2.0f * a);
+  const float t0 = (-b - sq) * inv2a;
+  const float t1 = (-b + sq) * inv2a;
   return (t0 >= 0.0f && t0 <= 1.0f) || (t1 >= 0.0f && t1 <= 1.0f);
 }