AP_Camera: changed update_location() to return true for camera trigger

Makes the main vehicle code responsible for taking a photo so logging can occur

libraries/AP_Camera/AP_Camera.cpp

@@ -216,24 +216,28 @@ AP_Camera::control_msg(mavlink_message_t* msg)
 }
 
 
-// update location, for triggering by GPS distance moved
-void AP_Camera::update_location(const struct Location &loc)
+/*  update location, for triggering by GPS distance moved
+    This function returns true if a picture should be taken
+    The caller is responsible for taking the picture based on the return value of this function.
+    The caller is also responsible for logging the details about the photo
+*/
+bool AP_Camera::update_location(const struct Location &loc)
 {
     if (_trigg_dist == 0.0f) {
-        return;
+        return false;
     }
     if (_last_location.lat == 0 && _last_location.lng == 0) {
         _last_location = loc;
-        return;
+        return false;
     }
     if (_last_location.lat == loc.lat && _last_location.lng == loc.lng) {
         // we haven't moved - this can happen as update_location() may
         // be called without a new GPS fix
-        return;
+        return false;
     }
     if (get_distance(&loc, &_last_location) < _trigg_dist) {
-        return;
+        return false;
     }
     _last_location = loc;
-    trigger_pic();
+    return true;
 }

libraries/AP_Camera/AP_Camera.h

@@ -54,7 +54,8 @@ public:
     void            configure_msg(mavlink_message_t* msg);
     void            control_msg(mavlink_message_t* msg);
 
-    void update_location(const struct Location &loc);
+    // Update location of vehicle and return true if a picture should be taken
+    bool update_location(const struct Location &loc);
 
     static const struct AP_Param::GroupInfo        var_info[];
 
@@ -72,7 +73,7 @@ private:
     void            throttle_pic();     // pictures blurry? use this trigger. Turns off the throttle until for # of cycles of medium loop then takes the picture and re-enables the throttle.
     void            distance_pic();     // pictures blurry? use this trigger. Turns off the throttle until closer to waypoint then takes the picture and re-enables the throttle.
     void            transistor_pic();   // hacked the circuit to run a transistor? use this trigger to send output.
-    
+
     AP_Float        _trigg_dist;     // distance between trigger points (meters)
     struct Location _last_location;