Add dedicated OSD elements for map scale and reference

Allows moving them around (or hiding them) rather than having them
on a fixed position.

Fixes #3794

src/main/cms/cms_menu_osd.c

@@ -205,6 +205,8 @@ static const OSD_Entry menuOsdElemsEntries[] =
     OSD_ELEMENT_ENTRY("MAP NORTH", OSD_MAP_NORTH),
     OSD_ELEMENT_ENTRY("MAP TAKE OFF", OSD_MAP_TAKEOFF),
     OSD_ELEMENT_ENTRY("RADAR", OSD_RADAR),
+    OSD_ELEMENT_ENTRY("MAP SCALE", OSD_MAP_SCALE),
+    OSD_ELEMENT_ENTRY("MAP REFERENCE", OSD_MAP_REFERENCE),
 #endif
     OSD_ELEMENT_ENTRY("EXPO", OSD_RC_EXPO),
     OSD_ELEMENT_ENTRY("YAW EXPO", OSD_RC_YAW_EXPO),

src/main/io/osd.c

@@ -170,6 +170,13 @@ static bool fullRedraw = false;
 
 static uint8_t armState;
 
+typedef struct osdMapData_s {
+    uint32_t scale;
+    char referenceSymbol;
+} osdMapData_t;
+
+static osdMapData_t osdMapData;
+
 static displayPort_t *osdDisplayPort;
 
 #define AH_MAX_PITCH_DEFAULT 20 // Specify default maximum AHI pitch value displayed (degrees)
@@ -953,8 +960,6 @@ static void osdDrawMap(int referenceHeading, uint8_t referenceSym, uint8_t cente
     const int charWidth = 12;
     const int charHeight = 18;
 
-    char buf[16];
-
     uint8_t minX = hMargin;
     uint8_t maxX = osdDisplayPort->cols - 1 - hMargin;
     uint8_t minY = vMargin;
@@ -963,11 +968,6 @@ static void osdDrawMap(int referenceHeading, uint8_t referenceSym, uint8_t cente
     uint8_t midY = osdDisplayPort->rows / 2;
 
     // Fixed marks
-    if (referenceSym) {
-        displayWriteChar(osdDisplayPort, maxX, minY, SYM_DIRECTION);
-        displayWriteChar(osdDisplayPort, maxX, minY + 1, referenceSym);
-    }
-    displayWriteChar(osdDisplayPort, minX, maxY, SYM_SCALE);
     displayWriteChar(osdDisplayPort, midX, midY, centerSym);
 
     // First, erase the previous drawing.
@@ -977,11 +977,6 @@ static void osdDrawMap(int referenceHeading, uint8_t referenceSym, uint8_t cente
     }
 
     uint32_t initialScale;
-    float scaleToUnit;
-    int scaleUnitDivisor;
-    char symUnscaled;
-    char symScaled;
-    int maxDecimals;
     const unsigned scaleMultiplier = 2;
     // We try to reduce the scale when the POI will be around half the distance
     // between the center and the closers map edge, to avoid too much jumping
@@ -990,21 +985,11 @@ static void osdDrawMap(int referenceHeading, uint8_t referenceSym, uint8_t cente
     switch (osdConfig()->units) {
         case OSD_UNIT_IMPERIAL:
             initialScale = 16; // 16m ~= 0.01miles
-            scaleToUnit = 100 / 1609.3440f; // scale to 0.01mi for osdFormatCentiNumber()
-            scaleUnitDivisor = 0;
-            symUnscaled = SYM_MI;
-            symScaled = SYM_MI;
-            maxDecimals = 2;
             break;
         case OSD_UNIT_UK:
             FALLTHROUGH;
         case OSD_UNIT_METRIC:
             initialScale = 10; // 10m as initial scale
-            scaleToUnit = 100; // scale to cm for osdFormatCentiNumber()
-            scaleUnitDivisor = 1000; // Convert to km when scale gets bigger than 999m
-            symUnscaled = SYM_M;
-            symScaled = SYM_KM;
-            maxDecimals = 0;
             break;
     }
 
@@ -1087,12 +1072,11 @@ static void osdDrawMap(int referenceHeading, uint8_t referenceSym, uint8_t cente
         }
     }
 
-    // Draw the used scale
-    bool scaled = osdFormatCentiNumber(buf, scale * scaleToUnit, scaleUnitDivisor, maxDecimals, 2, 3);
-    buf[3] = scaled ? symScaled : symUnscaled;
-    buf[4] = '\0';
-    displayWrite(osdDisplayPort, minX + 1, maxY, buf);
     *usedScale = scale;
+
+    // Update global map data for scale and reference
+    osdMapData.scale = scale;
+    osdMapData.referenceSymbol = referenceSym;
 }
 
 /* Draws a map with the home in the center and the craft moving around.
@@ -2467,6 +2451,59 @@ static bool osdDrawSingleElement(uint8_t item)
             break;
         }
 
+    case OSD_MAP_SCALE:
+        {
+            float scaleToUnit;
+            int scaleUnitDivisor;
+            char symUnscaled;
+            char symScaled;
+            int maxDecimals;
+
+            switch (osdConfig()->units) {
+            case OSD_UNIT_IMPERIAL:
+                scaleToUnit = 100 / 1609.3440f; // scale to 0.01mi for osdFormatCentiNumber()
+                scaleUnitDivisor = 0;
+                symUnscaled = SYM_MI;
+                symScaled = SYM_MI;
+                maxDecimals = 2;
+                break;
+            case OSD_UNIT_UK:
+                FALLTHROUGH;
+            case OSD_UNIT_METRIC:
+                scaleToUnit = 100; // scale to cm for osdFormatCentiNumber()
+                scaleUnitDivisor = 1000; // Convert to km when scale gets bigger than 999m
+                symUnscaled = SYM_M;
+                symScaled = SYM_KM;
+                maxDecimals = 0;
+                break;
+            }
+            buff[0] = SYM_SCALE;
+            if (osdMapData.scale > 0) {
+                bool scaled = osdFormatCentiNumber(&buff[1], osdMapData.scale * scaleToUnit, scaleUnitDivisor, maxDecimals, 2, 3);
+                buff[4] = scaled ? symScaled : symUnscaled;
+                // Make sure this is cleared if the map stops being drawn
+                osdMapData.scale = 0;
+            } else {
+                memset(&buff[1], '-', 4);
+            }
+            buff[5] = '\0';
+            break;
+        }
+    case OSD_MAP_REFERENCE:
+        {
+            char referenceSymbol;
+            if (osdMapData.referenceSymbol) {
+                referenceSymbol = osdMapData.referenceSymbol;
+                // Make sure this is cleared if the map stops being drawn
+                osdMapData.referenceSymbol = 0;
+            } else {
+                referenceSymbol = '-';
+            }
+            displayWriteChar(osdDisplayPort, elemPosX, elemPosY, SYM_DIRECTION);
+            displayWriteChar(osdDisplayPort, elemPosX, elemPosY + 1, referenceSymbol);
+            return true;
+        }
+
     default:
         return false;
     }
@@ -2522,7 +2559,7 @@ static uint8_t osdIncElementIndex(uint8_t elementIndex)
         if (elementIndex == OSD_TRIP_DIST) {
             elementIndex = OSD_ATTITUDE_PITCH;
         }
-        if (elementIndex == OSD_MAP_NORTH) {
+        if (elementIndex == OSD_WIND_SPEED_HORIZONTAL) {
             elementIndex = OSD_SAG_COMPENSATED_MAIN_BATT_VOLTAGE;
         }
         if (elementIndex == OSD_3D_SPEED) {

src/main/io/osd.h

@@ -134,6 +134,8 @@ typedef enum {
     OSD_TEMP_SENSOR_7_TEMPERATURE,
     OSD_ALTITUDE_MSL,
     OSD_PLUS_CODE,
+    OSD_MAP_SCALE,
+    OSD_MAP_REFERENCE,
     OSD_ITEM_COUNT // MUST BE LAST
 } osd_items_e;