(Location) Reimplement some parts of the location interface - get_latitude

and get_longitude are gone now in place of get_position. Basically,
from C land we basically do a poll-style queries, but on the
implementation side (ie. Android/iOS/OSX) - they all use callback-based
location updates. So we simply check in the poll function (get_position)
whether position has changed, and if so, update the pointer values and
return true - if not, set them to 0 and return false.

android/phoenix/src/com/retroarch/browser/retroactivity/RetroActivityLocation.java

@@ -32,7 +32,11 @@ LocationListener
 	// Define an object that holds accuracy and frequency parameters
 	LocationRequest mLocationRequest = null;
 	boolean mUpdatesRequested = false;
+	boolean locationChanged = false;
 	boolean location_service_running = false;
+	double current_latitude  = 0.0;
+	double current_longitude = 0.0;
+	double current_accuracy  = 0.0;
 
 	/*
 	 * Called by Location Services when the request to connect the
@@ -126,7 +130,7 @@ LocationListener
 	/**
 	 * Initializing methods for location based functionality.
 	 */
-	public void onLocationInit(int update_interval_in_ms, int distance_interval)
+	public void onLocationInit()
 	{
 		/*
 		 * Create a new location client, using the enclosing class to
@@ -141,7 +145,7 @@ LocationListener
 		if (mLocationRequest == null)
 			mLocationRequest = LocationRequest.create();
       
-      onLocationSetInterval(update_interval_in_ms, distance_interval);
+      onLocationSetInterval(0, 0);
 	}
 
 
@@ -209,11 +213,35 @@ LocationListener
 	{
 		return mCurrentLocation.getLongitude();
 	}
+	
+	/*
+	 * Gets the accuracy of the current location in meters.
+	 * 
+	 * @return the accuracy of the current position.
+	 */
+	public float onLocationGetAccuracy()
+	{
+		return mCurrentLocation.getAccuracy();
+	}
+	
+	/*
+	 * Tells us whether the location listener callback has
+	 * updated the current location since the last time
+	 * we polled.
+	 */
+	public boolean onLocationHasChanged()
+	{
+		boolean ret = locationChanged;
+		if (ret)
+			locationChanged = false;
+		return ret;
+	}
 
 	// Define the callback method that receives location updates
 	@Override
 	public void onLocationChanged(Location location)
 	{
+		locationChanged = true;
 		mCurrentLocation = location;
 
 		// Report to the UI that the location was updated

apple/common/RAGameView.m

@@ -23,6 +23,7 @@
 #include <CoreLocation/CoreLocation.h>
 
 static CLLocationManager *locationManager;
+static bool locationChanged;
 static CLLocationDegrees currentLatitude;
 static CLLocationDegrees currentLongitude;
 
@@ -314,7 +315,7 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
 }
 #endif
 
-- (void)onLocationSetInterval:(int)interval_update_ms interval_update_distance:(int)interval_distance
+- (void)onLocationSetInterval:(unsigned)interval_update_ms interval_update_distance:(unsigned)interval_distance
 {
    (void)interval_update_ms;
 
@@ -325,7 +326,7 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
        locationManager.distanceFilter = interval_distance;
 }
 
-- (void)onLocationInit:(int)interval_update_ms interval_update_distance:(int)interval_distance
+- (void)onLocationInit
 {
     // Create the location manager if this object does not
     // already have one.
@@ -335,7 +336,7 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
     locationManager.delegate = self;
     locationManager.desiredAccuracy = kCLLocationAccuracyBest;
 
-	[[RAGameView get] onLocationSetInterval:interval_update_ms interval_update_distance:interval_distance];
+	[[RAGameView get] onLocationSetInterval:0 interval_update_distance:0];
 }
 
 - (void)onLocationStart
@@ -363,8 +364,23 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
     return currentLongitude;
 }
 
+- (double)onLocationGetAccuracy
+{
+   /* TODO/FIXME - implement */
+   return 0.0;
+}
+
+- (bool)onLocationHasChanged
+{
+   bool ret = locationChanged;
+   if (ret)
+      locationChanged = false;
+   return ret;
+}
+
 - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
 {
+    locationChanged = true;
     currentLatitude = newLocation.coordinate.latitude;
     currentLongitude = newLocation.coordinate.longitude;
     RARCH_LOG("didUpdateToLocation - latitude %f, longitude %f\n", (float)currentLatitude, (float)currentLongitude);
@@ -372,7 +388,7 @@ didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
 
 - (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
 {
-
+    locationChanged = true;
     currentLatitude  = [[locations objectAtIndex:([locations     count]-1)] coordinate].latitude;
     currentLongitude = [[locations objectAtIndex:([locations     count]-1)] coordinate].longitude;
     RARCH_LOG("didUpdateLocations - latitude %f, longitude %f\n", (float)currentLatitude, (float)currentLongitude);
@@ -711,7 +727,7 @@ static void *apple_location_init(int interval_update_ms, int interval_distance)
 	return applelocation;
 }
 
-static void apple_location_set_interval(void *data, int interval_update_ms, int interval_distance)
+static void apple_location_set_interval(void *data, unsigned interval_update_ms, unsigned interval_distance)
 {
    (void)data;
 	
@@ -745,18 +761,25 @@ static void apple_location_stop(void *data)
 	[[RAGameView get] onLocationStop];
 }
 
-static double apple_location_get_latitude(void *data)
+static bool apple_location_get_position(void *data, double *lat, double *lon, double *accuracy)
 {
 	(void)data;
-	
-	return [[RAGameView get] onLocationGetLatitude];
-}
 
-static double apple_location_get_longitude(void *data)
+   bool ret = [[RAGameView get] onLocationHasChanged];
-{
+
-	(void)data;
+   if (!ret)
+      goto fail;
 	
-	return [[RAGameView get] onLocationGetLongitude];
+	*lat      = [[RAGameView get] onLocationGetLatitude];
+   *lon      = [[RAGameView get] onLocationGetLongitude];
+   *accuracy = [[RAGameView get] onLocationGetAccuracy];
+   return true;
+
+fail:
+   *lat      = 0.0;
+   *lon      = 0.0;
+   *accuracy = 0.0;
+   return false;
 }
 
 const location_driver_t location_apple = {
@@ -764,8 +787,7 @@ const location_driver_t location_apple = {
 	apple_location_free,
 	apple_location_start,
 	apple_location_stop,
-	apple_location_get_longitude,
+	apple_location_get_position,
-	apple_location_get_latitude,
 	apple_location_set_interval,
 	"apple",
 };

driver.c

@@ -648,20 +648,15 @@ void driver_location_set_interval(unsigned interval_msecs, unsigned interval_dis
       driver.location->set_interval(driver.location_data, interval_msecs, interval_distance);
 }
 
-double driver_location_get_latitude(void)
+bool driver_location_get_position(double *lat, double *lon, double *accuracy)
 {
    if (driver.location && driver.location_data)
-      return driver.location->get_latitude(driver.location_data);
+      return driver.location->get_position(driver.location_data, lat, lon, accuracy);
-   else
-      return 0.0;
-}
 
-double driver_location_get_longitude(void)
+   *lat = 0.0;
-{
+   *lon = 0.0;
-   if (driver.location && driver.location_data)
+   *accuracy = 0.0;
-      return driver.location->get_longitude(driver.location_data);
+   return false;
-   else
-      return 0.0;
 }
 #endif
 

driver.h

@@ -375,8 +375,7 @@ typedef struct location_driver
    bool (*start)(void *data);
    void (*stop)(void *data);
 
-   double (*get_longitude)(void *data);
+   bool (*get_position)(void *data, double *lat, double *lon, double *accuracy);
-   double (*get_latitude)(void *data);
    void (*set_interval)(void *data, unsigned interval_msecs, unsigned interval_distance);
    const char *ident;
 } location_driver_t;
@@ -604,8 +603,7 @@ void driver_camera_poll(void);
 #ifdef HAVE_LOCATION
 bool driver_location_start(void);
 void driver_location_stop(void);
-double driver_location_get_latitude(void);
+bool driver_location_get_position(double *lat, double *lon, double *accuracy);
-double driver_location_get_longitude(void);
 void driver_location_set_interval(unsigned interval_msecs, unsigned interval_distance);
 #endif
 

dynamic.c

@@ -849,8 +849,7 @@ bool rarch_environment_cb(unsigned cmd, void *data)
          struct retro_location_callback *cb = (struct retro_location_callback*)data;
          cb->start = driver_location_start;
          cb->stop = driver_location_stop;
-         cb->get_latitude = driver_location_get_latitude;
+         cb->get_position = driver_location_get_position;
-         cb->get_longitude = driver_location_get_longitude;
          cb->set_interval = driver_location_set_interval;
          g_extern.system.location_callback = *cb;
          g_extern.location_active = true;

libretro.h

@@ -764,18 +764,15 @@ typedef bool (*retro_location_start_t)(void);
 // location.
 typedef void (*retro_location_stop_t)(void);
 
-// Get the latitude of the current location.
+// Get the position of the current location. Will set parameters to 0 if no new
-typedef double (*retro_location_get_latitude_t)(void);
+// location update has happened since the last time.
-
+typedef bool (*retro_location_get_position_t)(double *lat, double *lon, double *accuracy);
-// Get the longitude of the current location.
-typedef double (*retro_location_get_longitude_t)(void);
 
 struct retro_location_callback
 {
    retro_location_start_t         start;
    retro_location_stop_t          stop;
-   retro_location_get_latitude_t  get_latitude;
+   retro_location_get_position_t  get_position;
-   retro_location_get_longitude_t get_longitude;
    retro_location_set_interval_t  set_interval; 
 };
 

location/android.c

@@ -26,6 +26,8 @@ typedef struct android_location
    jmethodID onLocationSetInterval;
    jmethodID onLocationGetLongitude;
    jmethodID onLocationGetLatitude;
+   jmethodID onLocationGetAccuracy;
+   jmethodID onLocationHasChanged;
 } androidlocation_t;
 
 static void *android_location_init(void)
@@ -46,7 +48,7 @@ static void *android_location_init(void)
    if (class == NULL)
       goto dealloc;
 
-   GET_METHOD_ID(env, androidlocation->onLocationInit, class, "onLocationInit", "(II)V");
+   GET_METHOD_ID(env, androidlocation->onLocationInit, class, "onLocationInit", "()V");
    if (!androidlocation->onLocationInit)
       goto dealloc;
 
@@ -70,14 +72,21 @@ static void *android_location_init(void)
    if (!androidlocation->onLocationGetLongitude)
       goto dealloc;
 
+   GET_METHOD_ID(env, androidlocation->onLocationGetAccuracy, class, "onLocationGetAccuracy", "()F");
+   if (!androidlocation->onLocationGetAccuracy)
+      goto dealloc;
+
    GET_METHOD_ID(env, androidlocation->onLocationGetLongitude, class, "onLocationSetInterval", "(II)V");
    if (!androidlocation->onLocationSetInterval)
       goto dealloc;
 
+   GET_METHOD_ID(env, androidlocation->onLocationHasChanged, class, "onLocationHasChanged", "()Z");
+   if (!androidlocation->onLocationHasChanged)
+      goto dealloc;
+
    CALL_VOID_METHOD(env, android_app->activity->clazz, androidlocation->onLocationInit);
 
    return androidlocation;
-
 dealloc:
    free(androidlocation);
    return NULL;
@@ -120,30 +129,40 @@ static void android_location_stop(void *data)
    CALL_VOID_METHOD(env, android_app->activity->clazz, androidlocation->onLocationStop);
 }
 
-static double android_location_get_latitude(void *data)
+static bool android_location_get_position(void *data, double *latitude, double *longitude, double *accuracy)
 {
    struct android_app *android_app = (struct android_app*)g_android;
    androidlocation_t *androidlocation = (androidlocation_t*)data;
    JNIEnv *env = jni_thread_getenv();
    if (!env)
-      return 0.0;
+      goto fail;
 
-   jdouble latitude;
+   jdouble lat, lon, accuhurtz;
-   CALL_BOOLEAN_METHOD(env, latitude, android_app->activity->clazz, androidlocation->onLocationGetLatitude);
+   jboolean newLocation;
-   return latitude;
-}
 
-static double android_location_get_longitude(void *data)
+   CALL_BOOLEAN_METHOD(env, newLocation, android_app->activity->clazz, androidlocation->onLocationHasChanged);
-{
-   struct android_app *android_app = (struct android_app*)g_android;
-   androidlocation_t *androidlocation = (androidlocation_t*)data;
-   JNIEnv *env = jni_thread_getenv();
-   if (!env)
-      return 0.0;
 
-   jdouble longitude;
+   if (!newLocation)
-   CALL_BOOLEAN_METHOD(env, longitude, android_app->activity->clazz, androidlocation->onLocationGetLongitude);
+      goto fail;
-   return longitude;
+
+   CALL_DOUBLE_METHOD(env, lat,        android_app->activity->clazz, androidlocation->onLocationGetLatitude);
+   CALL_DOUBLE_METHOD(env, lon,        android_app->activity->clazz, androidlocation->onLocationGetLongitude);
+   CALL_DOUBLE_METHOD(env, accuhurtz,  android_app->activity->clazz, androidlocation->onLocationGetAccuracy);
+
+   if (lat != 0.0)
+      *latitude = lat;
+   if (lon != 0.0)
+      *longitude = lon;
+   if (accuhurtz != 0.0)
+      *accuracy = accuhurtz;
+
+   return true;
+
+fail:
+   *latitude  = 0.0;
+   *longitude = 0.0;
+   *accuracy  = 0.0;
+   return false;
 }
 
 static void android_location_set_interval(void *data, unsigned interval_ms, unsigned interval_distance)
@@ -154,7 +173,7 @@ static void android_location_set_interval(void *data, unsigned interval_ms, unsi
    if (!env)
       return;
 
-   CALL_VOID_METHOD_PARAM(env, android_app->activity->clazz, androidlocation->onLocationSetInterval, interval_ms, interval_distance);
+   CALL_VOID_METHOD_PARAM(env, android_app->activity->clazz, androidlocation->onLocationSetInterval, (int)interval_ms, (int)interval_distance);
 }
 
 const location_driver_t location_android = {
@@ -162,8 +181,7 @@ const location_driver_t location_android = {
    android_location_free,
    android_location_start,
    android_location_stop,
-   android_location_get_longitude,
+   android_location_get_position,
-   android_location_get_latitude,
    android_location_set_interval,
    "android",
 };