AP_Camera: Camera options for better camera control

All on one because they would not pass autotest if split up.

libraries/AP_Camera/AP_Camera.cpp

@@ -55,10 +55,27 @@ const AP_Param::GroupInfo AP_Camera::var_info[] = {
     // @Values: 0:Low,1:High
     // @User: Standard
     AP_GROUPINFO("RELAY_ON",    5, AP_Camera, _relay_on, 1),
-    
+
+    // @Param: MIN_INTERVAL
+    // @DisplayName: Minimum time between photos
+    // @Description: Postpone shooting if previous picture was taken less than preset time(ms) ago.
+    // @User: Standard
+    // @Units: milliseconds
+    // @Range: 0 10000
+    AP_GROUPINFO("MIN_INTERVAL",  6, AP_Camera, _min_interval, 0),
+
+    // @Param: MAX_ROLL
+    // @DisplayName: Maximum photo roll angle.
+    // @Description: Postpone shooting if roll is greater than limit. (0=Disable, will shoot regardless of roll).
+    // @User: Standard
+    // @Units: Degrees
+    // @Range: 0 180
+    AP_GROUPINFO("MAX_ROLL",  7, AP_Camera, _max_roll, 0),
+
     AP_GROUPEND
 };
 
+extern const AP_HAL::HAL& hal;
 
 /// Servo operated camera
 void
@@ -228,7 +245,7 @@ void AP_Camera::send_feedback(mavlink_channel_t chan, AP_GPS &gps, const AP_AHRS
     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)
+bool AP_Camera::update_location(const struct Location &loc, const AP_AHRS &ahrs)
 {
     if (is_zero(_trigg_dist)) {
         return false;
@@ -242,9 +259,21 @@ bool AP_Camera::update_location(const struct Location &loc)
         // be called without a new GPS fix
         return false;
     }
+
     if (get_distance(loc, _last_location) < _trigg_dist) {
         return false;
     }
-    _last_location = loc;
+
-    return true;
+    if (_max_roll > 0 && labs(ahrs.roll_sensor/100) > _max_roll) {
+        return false;
+    }
+
+    uint32_t tnow = AP_HAL::millis();
+    if (tnow - _last_photo_time < (unsigned) _min_interval) {
+        return false;
+    }  else {
+        _last_location = loc;
+        _last_photo_time = tnow;
+        return true;
+    }
 }

libraries/AP_Camera/AP_Camera.h

@@ -60,7 +60,7 @@ public:
     void            set_trigger_distance(uint32_t distance_m) { _trigg_dist.set(distance_m); }
 
     // Update location of vehicle and return true if a picture should be taken
-    bool update_location(const struct Location &loc);
+    bool update_location(const struct Location &loc, const AP_AHRS &ahrs);
 
     static const struct AP_Param::GroupInfo        var_info[];
 
@@ -77,6 +77,9 @@ private:
     void            relay_pic();        // basic relay activation
 
     AP_Float        _trigg_dist;        // distance between trigger points (meters)
+    AP_Int16        _min_interval;      // Minimum time between shots required by camera
+    AP_Int16        _max_roll;          // Maximum acceptable roll angle when trigging camera
+    uint32_t        _last_photo_time;   // last time a photo was taken
     struct Location _last_location;
     uint16_t        _image_index;       // number of pictures taken since boot