util.h: add unit conversion constants (#22813)

* Add unit conversion constants.

* move to common/util.h

selfdrive/common/util.h

@@ -30,6 +30,13 @@
 typedef void (*sighandler_t)(int sig);
 #endif
 
+const double MILE_TO_KM = 1.609344;
+const double KM_TO_MILE = 1. / MILE_TO_KM;
+const double MS_TO_KPH = 3.6;
+const double MS_TO_MPH = MS_TO_KPH * KM_TO_MILE;
+const double METER_TO_MILE = KM_TO_MILE / 1000.0;
+const double METER_TO_FOOT = 3.28084;
+
 void set_thread_name(const char* name);
 
 int set_realtime_priority(int level);

selfdrive/ui/paint.cc

@@ -155,7 +155,7 @@ static void ui_draw_vision_maxspeed(UIState *s) {
   const int SET_SPEED_NA = 255;
   float maxspeed = (*s->sm)["controlsState"].getControlsState().getVCruise();
   const bool is_cruise_set = maxspeed != 0 && maxspeed != SET_SPEED_NA;
-  if (is_cruise_set && !s->scene.is_metric) { maxspeed *= 0.6225; }
+  if (is_cruise_set && !s->scene.is_metric) { maxspeed *= KM_TO_MILE; }
 
   const Rect rect = {bdr_s * 2, int(bdr_s * 1.5), 184, 202};
   ui_fill_rect(s->vg, rect, COLOR_BLACK_ALPHA(100), 30.);
@@ -172,7 +172,7 @@ static void ui_draw_vision_maxspeed(UIState *s) {
 }
 
 static void ui_draw_vision_speed(UIState *s) {
-  const float speed = std::max(0.0, (*s->sm)["carState"].getCarState().getVEgo() * (s->scene.is_metric ? 3.6 : 2.2369363));
+  const float speed = std::max(0.0, (*s->sm)["carState"].getCarState().getVEgo() * (s->scene.is_metric ? MS_TO_KPH : MS_TO_MPH));
   const std::string speed_str = std::to_string((int)std::nearbyint(speed));
   nvgTextAlign(s->vg, NVG_ALIGN_CENTER | NVG_ALIGN_BASELINE);
   ui_draw_text(s, s->fb_w/2, 210, speed_str.c_str(), 96 * 2.5, COLOR_WHITE, "sans-bold");

selfdrive/ui/qt/maps/map.cc

@@ -381,8 +381,8 @@ void MapInstructions::updateDistance(float d) {
       distance_str += " m";
     }
   } else {
-    float miles = d * METER_2_MILE;
-    float feet = d * METER_2_FOOT;
+    float miles = d * METER_TO_MILE;
+    float feet = d * METER_TO_FOOT;
 
     if (feet > 500) {
       distance_str.setNum(miles, 'f', 1);
@@ -597,7 +597,7 @@ void MapETA::updateETA(float s, float s_typical, float d) {
     num = d / 1000.0;
     distance_unit->setText("km");
   } else {
-    num = d * METER_2_MILE;
+    num = d * METER_TO_MILE;
     distance_unit->setText("mi");
   }
 

selfdrive/ui/qt/maps/map_helpers.h

@@ -9,8 +9,6 @@
 #include "common/transformations/orientation.hpp"
 #include "cereal/messaging/messaging.h"
 
-const float METER_2_MILE = 0.000621371;
-const float METER_2_FOOT = 3.28084;
 #define RAD2DEG(x) ((x) * 180.0 / M_PI)
 
 QGeoCoordinate to_QGeoCoordinate(const QMapbox::Coordinate &in);

selfdrive/ui/qt/widgets/drive_stats.cc

@@ -9,8 +9,6 @@
 #include "selfdrive/ui/qt/request_repeater.h"
 #include "selfdrive/ui/qt/util.h"
 
-const double MILE_TO_KM = 1.60934;
-
 static QLabel* newLabel(const QString& text, const QString &type) {
   QLabel* label = new QLabel(text);
   label->setProperty("type", type);