Merge pull request #10555 from etracer65/osd_element_print_float

Add a common function used to print formatted floats in the OSD

src/main/osd/osd.c

@@ -186,6 +186,45 @@ const osd_stats_e osdStatsDisplayOrder[OSD_STAT_COUNT] = {
     OSD_STAT_TOTAL_DIST,
 };
 
+// Format a float to the specified number of decimal places with optional rounding.
+// OSD symbols can optionally be placed before and after the formatted number (use SYM_NONE for no symbol).
+// The formatString can be used for customized formatting of the integer part. Follow the printf style.
+// Pass an empty formatString for default.
+int osdPrintFloat(char *buffer, char leadingSymbol, float value, char *formatString, unsigned decimalPlaces, bool round, char trailingSymbol)
+{
+    char mask[7];
+    int pos = 0;
+    int multiplier = 1;
+    for (unsigned i = 0; i < decimalPlaces; i++) {
+        multiplier *= 10;
+    }
+
+    value *= multiplier;
+    const int scaledValueAbs = ABS(round ? lrintf(value) : value);
+    const int integerPart = scaledValueAbs / multiplier;
+    const int fractionalPart = scaledValueAbs % multiplier;
+
+    if (leadingSymbol != SYM_NONE) {
+        buffer[pos++] = leadingSymbol;
+    }
+    if (value < 0 && (integerPart || fractionalPart)) {
+        buffer[pos++] = '-';
+    }
+
+    pos += tfp_sprintf(buffer + pos, (strlen(formatString) ? formatString : "%01u"), integerPart);
+    if (decimalPlaces) {
+        tfp_sprintf((char *)&mask, ".%%0%uu", decimalPlaces); // builds up the format string to be like ".%03u" for decimalPlaces == 3 as an example
+        pos += tfp_sprintf(buffer + pos, mask, fractionalPart);
+    }
+
+    if (trailingSymbol != SYM_NONE) {
+        buffer[pos++] = trailingSymbol;
+    }
+    buffer[pos] = '\0';
+
+    return pos;
+}
+
 void osdStatSetState(uint8_t statIndex, bool enabled)
 {
     if (enabled) {
@@ -658,8 +697,7 @@ static bool osdDisplayStat(int statistic, uint8_t displayRow)
         return true;
 
     case OSD_STAT_MAX_ALTITUDE: {
-        const int alt = osdGetMetersToSelectedUnit(stats.max_altitude) / 10;
+        osdPrintFloat(buff, SYM_NONE, osdGetMetersToSelectedUnit(stats.max_altitude) / 100.0f, "", 1, true, osdGetMetersToSelectedUnitSymbol());
-        tfp_sprintf(buff, "%d.%d%c", alt / 10, alt % 10, osdGetMetersToSelectedUnitSymbol());
         osdDisplayStatisticLabel(displayRow, "MAX ALTITUDE", buff);
         return true;
     }
@@ -692,19 +730,19 @@ static bool osdDisplayStat(int statistic, uint8_t displayRow)
 #endif
 
     case OSD_STAT_MIN_BATTERY:
-        tfp_sprintf(buff, "%d.%02d%c", stats.min_voltage / 100, stats.min_voltage % 100, SYM_VOLT);
+        osdPrintFloat(buff, SYM_NONE, stats.min_voltage / 100.0f, "", 2, true, SYM_VOLT);
         osdDisplayStatisticLabel(displayRow, osdConfig()->stat_show_cell_value? "MIN AVG CELL" : "MIN BATTERY", buff);
         return true;
 
     case OSD_STAT_END_BATTERY:
-        tfp_sprintf(buff, "%d.%02d%c", stats.end_voltage / 100, stats.end_voltage % 100, SYM_VOLT);
+        osdPrintFloat(buff, SYM_NONE, stats.end_voltage / 100.0f, "", 2, true, SYM_VOLT);
         osdDisplayStatisticLabel(displayRow, osdConfig()->stat_show_cell_value ? "END AVG CELL" : "END BATTERY", buff);
         return true;
 
     case OSD_STAT_BATTERY: 
         {
             const uint16_t statsVoltage = getStatsVoltage();
-            tfp_sprintf(buff, "%d.%02d%c", statsVoltage / 100, statsVoltage % 100, SYM_VOLT);
+            osdPrintFloat(buff, SYM_NONE, statsVoltage / 100.0f, "", 2, true, SYM_VOLT);
             osdDisplayStatisticLabel(displayRow, osdConfig()->stat_show_cell_value ? "AVG BATT CELL" : "BATTERY", buff);
             return true;
         }
@@ -756,8 +794,7 @@ static bool osdDisplayStat(int statistic, uint8_t displayRow)
 #if defined(USE_ACC)
     case OSD_STAT_MAX_G_FORCE:
         if (sensors(SENSOR_ACC)) {
-            const int gForce = lrintf(stats.max_g_force * 10);
+            osdPrintFloat(buff, SYM_NONE, stats.max_g_force, "", 1, true, 'G');
-            tfp_sprintf(buff, "%01d.%01dG", gForce / 10, gForce % 10);
             osdDisplayStatisticLabel(displayRow, "MAX G-FORCE", buff);
             return true;
         }

src/main/osd/osd.h

@@ -354,3 +354,4 @@ bool osdElementVisible(uint16_t value);
 bool osdGetVisualBeeperState(void);
 statistic_t *osdGetStats(void);
 bool osdNeedsAccelerometer(void);
+int osdPrintFloat(char *buffer, char leadingSymbol, float value, char *formatString, unsigned decimalPlaces, bool round, char trailingSymbol);

src/main/osd/osd_elements.c

@@ -257,23 +257,19 @@ int osdConvertTemperatureToSelectedUnit(int tempInDegreesCelcius)
 
 static void osdFormatAltitudeString(char * buff, int32_t altitudeCm, osdElementType_e variantType)
 {
-    const int alt = ABS(osdGetMetersToSelectedUnit(altitudeCm) / 10);
     const char unitSymbol = osdGetMetersToSelectedUnitSymbol();
-
+    unsigned decimalPlaces;
-    *buff++ = SYM_ALTITUDE;
-    if (altitudeCm < 0) {
-        *buff++ = '-';
-    }
 
     switch (variantType) {
     case OSD_ELEMENT_TYPE_2:  // whole number altitude (no decimal places)
-        tfp_sprintf(buff, "%d%c", alt / 10, unitSymbol);
+        decimalPlaces = 0;
         break;
     case OSD_ELEMENT_TYPE_1:  // one decimal place (default)
     default:
-        tfp_sprintf(buff, "%01d.%01d%c", alt / 10 , alt % 10, unitSymbol);
+        decimalPlaces = 1;
         break;
     }
+    osdPrintFloat(buff, SYM_ALTITUDE, osdGetMetersToSelectedUnit(altitudeCm) / 100.0f, "", decimalPlaces, true, unitSymbol);
 }
 
 #ifdef USE_GPS
@@ -284,6 +280,8 @@ static void osdFormatCoordinate(char *buff, char sym, int32_t val)
     // We show 7 decimals, so we need to use 12 characters:
     // eg: s-180.1234567z   s=symbol, z=zero terminator, decimal separator  between 0 and 1
 
+    // NOTE: Don't use osdPrintFloat() for this. There are too many decimal places and float math doesn't have enough precision
+
     int pos = 0;
     buff[pos++] = sym;
     if (val < 0) {
@@ -296,14 +294,11 @@ static void osdFormatCoordinate(char *buff, char sym, int32_t val)
 
 void osdFormatDistanceString(char *ptr, int distance, char leadingSymbol)
 {
-    const int convertedDistance = osdGetMetersToSelectedUnit(distance);
+    const float convertedDistance = osdGetMetersToSelectedUnit(distance);
     char unitSymbol;
     char unitSymbolExtended;
     int unitTransition;
 
-    if (leadingSymbol != SYM_NONE) {
-        *ptr++ = leadingSymbol;
-    }
     switch (osdConfig()->units) {
     case UNIT_IMPERIAL:
         unitTransition = 5280;
@@ -317,16 +312,23 @@ void osdFormatDistanceString(char *ptr, int distance, char leadingSymbol)
         break;
     }
 
+    unsigned decimalPlaces;
+    float displayDistance;
+    char displaySymbol;
     if (convertedDistance < unitTransition) {
-        tfp_sprintf(ptr, "%d%c", convertedDistance, unitSymbol);
+        decimalPlaces = 0;
+        displayDistance = convertedDistance;
+        displaySymbol = unitSymbol;
     } else {
-        const int displayDistance = convertedDistance * 100 / unitTransition;
+        displayDistance = convertedDistance / unitTransition;
-        if (displayDistance >= 1000) { // >= 10 miles or km - 1 decimal place
+        displaySymbol = unitSymbolExtended;
-            tfp_sprintf(ptr, "%d.%d%c", displayDistance / 100, (displayDistance / 10) % 10, unitSymbolExtended);
+        if (displayDistance >= 10) { // >= 10 miles or km - 1 decimal place
+            decimalPlaces = 1;
         } else {                     // < 10 miles or km - 2 decimal places
-            tfp_sprintf(ptr, "%d.%02d%c", displayDistance / 100, displayDistance % 100, unitSymbolExtended);
+            decimalPlaces = 2;
         }
     }
+    osdPrintFloat(ptr, leadingSymbol, displayDistance, "", decimalPlaces, false, displaySymbol);
 }
 
 static void osdFormatPID(char * buff, const char * label, const pidf_t * pid)
@@ -464,13 +466,13 @@ static uint8_t osdGetDirectionSymbolFromHeading(int heading)
  * Converts altitude based on the current unit system.
  * @param meters Value in meters to convert
  */
-int32_t osdGetMetersToSelectedUnit(int32_t meters)
+float osdGetMetersToSelectedUnit(int32_t meters)
 {
     switch (osdConfig()->units) {
     case UNIT_IMPERIAL:
-        return (meters * 328) / 100; // Convert to feet / 100
+        return meters * 3.28084f;       // Convert to feet
     default:
-        return meters;               // Already in metre / 100
+        return meters;                  // Already in meters
     }
 }
 
@@ -574,8 +576,8 @@ static void osdElementAltitude(osdElementParms_t *element)
 #ifdef USE_ACC
 static void osdElementAngleRollPitch(osdElementParms_t *element)
 {
-    const int angle = (element->item == OSD_PITCH_ANGLE) ? attitude.values.pitch : attitude.values.roll;
+    const float angle = ((element->item == OSD_PITCH_ANGLE) ? attitude.values.pitch : attitude.values.roll) / 10.0f;
-    tfp_sprintf(element->buff, "%c%c%02d.%01d", (element->item == OSD_PITCH_ANGLE) ? SYM_PITCH : SYM_ROLL , angle < 0 ? '-' : ' ', abs(angle / 10), abs(angle % 10));
+    osdPrintFloat(element->buff, (element->item == OSD_PITCH_ANGLE) ? SYM_PITCH : SYM_ROLL, fabsf(angle), ((angle < 0) ? "-%02u" : " %02u"), 1, true, SYM_NONE);
 }
 #endif
 
@@ -645,8 +647,7 @@ static void osdElementUpDownReference(osdElementParms_t *element)
 static void osdElementAverageCellVoltage(osdElementParms_t *element)
 {
     const int cellV = getBatteryAverageCellVoltage();
-    element->buff[0] = osdGetBatterySymbol(cellV);
+    osdPrintFloat(element->buff, osdGetBatterySymbol(cellV), cellV / 100.0f, "", 2, false, SYM_VOLT);
-    tfp_sprintf(element->buff + 1, "%d.%02d%c", cellV / 100, cellV % 100, SYM_VOLT);
 }
 
 static void osdElementCompassBar(osdElementParms_t *element)
@@ -757,8 +758,8 @@ static void osdElementCrosshairs(osdElementParms_t *element)
 
 static void osdElementCurrentDraw(osdElementParms_t *element)
 {
-    const int32_t amperage = getAmperage();
+    const float amperage = fabsf(getAmperage() / 100.0f);
-    tfp_sprintf(element->buff, "%3d.%02d%c", abs(amperage) / 100, abs(amperage) % 100, SYM_AMP);
+    osdPrintFloat(element->buff, SYM_NONE, amperage, "%3u", 2, false, SYM_AMP);
 }
 
 static void osdElementDebug(osdElementParms_t *element)
@@ -907,8 +908,7 @@ static void osdElementFlymode(osdElementParms_t *element)
 #ifdef USE_ACC
 static void osdElementGForce(osdElementParms_t *element)
 {
-    const int gForce = lrintf(osdGForce * 10);
+    osdPrintFloat(element->buff, SYM_NONE, osdGForce, "", 1, true, 'G');
-    tfp_sprintf(element->buff, "%01d.%01dG", gForce / 10, gForce % 10);
 }
 #endif // USE_ACC
 
@@ -965,10 +965,10 @@ static void osdElementGpsLongitude(osdElementParms_t *element)
 
 static void osdElementGpsSats(osdElementParms_t *element)
 {
-    if (osdConfig()->gps_sats_show_hdop) {
+    int pos = tfp_sprintf(element->buff, "%c%c%2d", SYM_SAT_L, SYM_SAT_R, gpsSol.numSat);
-        tfp_sprintf(element->buff, "%c%c%2d %d.%d", SYM_SAT_L, SYM_SAT_R, gpsSol.numSat, gpsSol.hdop / 100, (gpsSol.hdop / 10) % 10);
+    if (osdConfig()->gps_sats_show_hdop) { // add on the GPS module HDOP estimate
-    } else {
+        element->buff[pos++] = ' ';
-        tfp_sprintf(element->buff, "%c%c%2d", SYM_SAT_L, SYM_SAT_R, gpsSol.numSat);
+        osdPrintFloat(element->buff + pos, SYM_NONE, gpsSol.hdop / 100.0f, "", 1, true, SYM_NONE);
     }
 }
 
@@ -1115,15 +1115,15 @@ static void osdElementMainBatteryUsage(osdElementParms_t *element)
 
 static void osdElementMainBatteryVoltage(osdElementParms_t *element)
 {
-    int batteryVoltage = getBatteryVoltage();
+    unsigned decimalPlaces;
+    const float batteryVoltage = getBatteryVoltage() / 100.0f;
 
-    element->buff[0] = osdGetBatterySymbol(getBatteryAverageCellVoltage());
+    if (batteryVoltage >= 10) { // if voltage is 10v or more then display only 1 decimal place
-    if (batteryVoltage >= 1000) {
+        decimalPlaces = 1;
-        batteryVoltage = (batteryVoltage + 5) / 10;
-        tfp_sprintf(element->buff + 1, "%d.%d%c", batteryVoltage / 10, batteryVoltage % 10, SYM_VOLT);
     } else {
-        tfp_sprintf(element->buff + 1, "%d.%02d%c", batteryVoltage / 100, batteryVoltage % 100, SYM_VOLT);
+        decimalPlaces = 2;
     }
+    osdPrintFloat(element->buff, osdGetBatterySymbol(getBatteryAverageCellVoltage()), batteryVoltage, "", decimalPlaces, true, SYM_VOLT);
 }
 
 static void osdElementMotorDiagnostics(osdElementParms_t *element)
@@ -1164,9 +1164,9 @@ static void osdElementNumericalVario(osdElementParms_t *element)
     haveGps = sensors(SENSOR_GPS) && STATE(GPS_FIX);
 #endif // USE_GPS
     if (haveBaro || haveGps) {
-        const int verticalSpeed = osdGetMetersToSelectedUnit(getEstimatedVario());
+        const float verticalSpeed = osdGetMetersToSelectedUnit(getEstimatedVario()) / 100.0f;
         const char directionSymbol = verticalSpeed < 0 ? SYM_ARROW_SMALL_DOWN : SYM_ARROW_SMALL_UP;
-        tfp_sprintf(element->buff, "%c%01d.%01d%c", directionSymbol, abs(verticalSpeed / 100), abs((verticalSpeed % 100) / 10), osdGetVarioToSelectedUnitSymbol());
+        osdPrintFloat(element->buff, directionSymbol, fabsf(verticalSpeed), "", 1, true, osdGetVarioToSelectedUnitSymbol());
     } else {
         // We use this symbol when we don't have a valid measure
         element->buff[0] = SYM_HYPHEN;

src/main/osd/osd_elements.h

@@ -49,7 +49,7 @@ void osdFormatDistanceString(char *result, int distance, char leadingSymbol);
 bool osdFormatRtcDateTime(char *buffer);
 void osdFormatTime(char * buff, osd_timer_precision_e precision, timeUs_t time);
 void osdFormatTimer(char *buff, bool showSymbol, bool usePrecision, int timerIndex);
-int32_t osdGetMetersToSelectedUnit(int32_t meters);
+float osdGetMetersToSelectedUnit(int32_t meters);
 char osdGetMetersToSelectedUnitSymbol(void);
 int32_t osdGetSpeedToSelectedUnit(int32_t value);
 char osdGetSpeedToSelectedUnitSymbol(void);

src/test/unit/osd_unittest.cc

@@ -263,7 +263,7 @@ void simulateFlight(void)
     GPS_distanceToHome = 100;
     GPS_distanceFlownInCm = 10000;
     simulationBatteryVoltage = 1470;
-    simulationAltitude = 200;
+    simulationAltitude = 200; // converts to 6.56168 feet which rounds to 6.6 in imperial units stats test
     simulationTime += 1e6;
     osdRefresh(simulationTime);
 
@@ -501,7 +501,7 @@ TEST_F(OsdTest, TestStatsImperial)
     // then
     // statistics screen should display the following
     int row = 5;
-    displayPortTestBufferSubstring(2, row++, "MAX ALTITUDE      : 6.5%c", SYM_FT);
+    displayPortTestBufferSubstring(2, row++, "MAX ALTITUDE      : 6.6%c", SYM_FT);
     displayPortTestBufferSubstring(2, row++, "MAX SPEED         : 17");
     displayPortTestBufferSubstring(2, row++, "MAX DISTANCE      : 3772%c", SYM_FT);
     displayPortTestBufferSubstring(2, row++, "FLIGHT DISTANCE   : 6.52%c", SYM_MILES);
@@ -905,28 +905,28 @@ TEST_F(OsdTest, TestElementAltitude)
     displayPortTestBufferSubstring(23, 7, "%c0.0%c", SYM_ALTITUDE, SYM_M);
 
     // when
-    simulationAltitude = 247;
+    simulationAltitude = 247;  // rounds to 2.5m
     displayClearScreen(&testDisplayPort);
     osdRefresh(simulationTime);
 
     // then
-    displayPortTestBufferSubstring(23, 7, "%c2.4%c", SYM_ALTITUDE, SYM_M);
+    displayPortTestBufferSubstring(23, 7, "%c2.5%c", SYM_ALTITUDE, SYM_M);
 
     // when
-    simulationAltitude = 4247;
+    simulationAltitude = 4247;  // rounds to 42.5m
     displayClearScreen(&testDisplayPort);
     osdRefresh(simulationTime);
 
     // then
-    displayPortTestBufferSubstring(23, 7, "%c42.4%c", SYM_ALTITUDE, SYM_M);
+    displayPortTestBufferSubstring(23, 7, "%c42.5%c", SYM_ALTITUDE, SYM_M);
 
     // when
-    simulationAltitude = -247;
+    simulationAltitude = -247;  // rounds to -2.5m
     displayClearScreen(&testDisplayPort);
     osdRefresh(simulationTime);
 
     // then
-    displayPortTestBufferSubstring(23, 7, "%c-2.4%c", SYM_ALTITUDE, SYM_M);
+    displayPortTestBufferSubstring(23, 7, "%c-2.5%c", SYM_ALTITUDE, SYM_M);
 
     // when
     simulationAltitude = -70;