Changeset 25808 in osm

Timestamp:

2011-04-06T21:23:49+02:00 (14 years ago)

Author:

glebius

Message:

Make a compromise between smoothness of updating and CPU consumption. Redrawing
only the LiveGPS layer is usually cheaper than scrolling the MapView with all its
layers, so introduce two independable tunables to configure update frequency, here
are their names and default values:

livegps.center_interval_msec=5000
livegps.refresh_interval_msec=250

The centering is made once per 5 seconds (old conservative value), but
the cursor can be redrawn up to 4 times per second.

File:

• applications/editors/josm/plugins/livegps/src/livegps/LiveGpsLayer.java (modified) (7 diffs)

applications/editors/josm/plugins/livegps/src/livegps/LiveGpsLayer.java

@@ -26 +26 @@
     public static final String KEY_LIVEGPS_COLOR = "color.livegps.position";
 
-    private static final int DEFAULT_SLEEP_TIME = 500;  /* Default sleep time is 0.5 seconds. */
-    private static final String oldConfigKey = "livegps.refreshinterval";     /* in seconds */
-    private static final String ConfigKey = "livegps.refresh_interval_msec";  /* in msec */
-    private int sleepTime;
+    private static final int DEFAULT_REFRESH_INTERVAL = 250;
+    private static final int DEFAULT_CENTER_INTERVAL = 5000;
+    private static final String oldC_REFRESH_INTERVAL = "livegps.refreshinterval";     /* in seconds */
+    private static final String C_REFRESH_INTERVAL = "livegps.refresh_interval_msec";  /* in msec */
+    private static final String C_CENTER_INTERVAL = "livegps.center_interval_msec";  /* in msec */
+    private int refreshInterval;
+    private int centerInterval;
+    private long lastRedraw = 0;
+    private long lastCenter = 0;
 
     LatLon lastPos;
@@ -39 +44 @@
     boolean autocenter;
     private SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
-    private long lastUpdate = 0;
 
     public LiveGpsLayer(GpxData data) {
@@ -51 +55 @@
         data.tracks.add(trackBeingWritten);
 
-        initSleepTime();
+        initIntervals();
     }
 
     void setCurrentPosition(double lat, double lon) {
-        // System.out.println("adding pos " + lat + "," + lon);
         LatLon thisPos = new LatLon(lat, lon);
-        if ((lastPos != null) && (thisPos.equalsEpsilon(lastPos))) {
+        if ((lastPos != null) && (thisPos.equalsEpsilon(lastPos)))
             // no change in position
             // maybe show a "paused" cursor or some such
             return;
-        }
 
         lastPos = thisPos;
@@ -67 +69 @@
         lastPoint.attr.put("time", dateFormat.format(new Date()));
         trackSegment.addWaypoint(lastPoint);
-        if (autocenter && allowRedraw()) {
+        if (autocenter && allowCenter())
             center();
-        }
     }
 
@@ -145 +146 @@
                     setCourse(data.getCourse());
                 }
-                if (!autocenter && allowRedraw()) {
+                if (allowRedraw())
                     Main.map.repaint();
-                }
             }
         }
@@ -162 +162 @@
         long current = date.getTime();
 
-        if (current - lastUpdate >= sleepTime) {
-                lastUpdate = current;
+        if (current - lastRedraw >= refreshInterval) {
+                lastRedraw = current;
                 return true;
         } else
@@ -170 +170 @@
 
     /**
-     * Retrieve the sleepTime from the configuration. Be compatible with old
-     * version that stored value in seconds. If no such configuration key exists,
-     * it will be initialized here.
-     */
-    private void initSleepTime() {
-        if ((sleepTime = Main.pref.getInteger(ConfigKey, 0)) == 0) {
-                if ((sleepTime = Main.pref.getInteger(oldConfigKey, 0)) != 0) {
-                        sleepTime *= 1000;
-                        Main.pref.put(oldConfigKey, null);
+     * Check, if a autocentering is currently allowed.
+     *
+     * @return true, if a autocentering is permitted, false, if a autocentering
+     * should be suppressed.
+     */
+    private boolean allowCenter() {
+        Date date = new Date();
+        long current = date.getTime();
+
+        if (current - lastCenter >= centerInterval) {
+                lastCenter = current;
+                return true;
+        } else
+                return false;
+    }
+
+    /**
+     * Retrieve the refreshInterval and centerInterval from the configuration. Be compatible
+     * with old version that stored refreshInterval in seconds. If no such configuration key
+     * exists, it will be initialized here.
+     */
+    private void initIntervals() {
+        if ((refreshInterval = Main.pref.getInteger(C_REFRESH_INTERVAL, 0)) == 0) {
+                if ((refreshInterval = Main.pref.getInteger(oldC_REFRESH_INTERVAL, 0)) != 0) {
+                        refreshInterval *= 1000;
+                        Main.pref.put(oldC_REFRESH_INTERVAL, null);
                 } else
-                        sleepTime = DEFAULT_SLEEP_TIME;
-        }
-
-        // creates the setting, if none present.
-        Main.pref.putInteger(ConfigKey, sleepTime);
+                        refreshInterval = DEFAULT_REFRESH_INTERVAL;
+        }
+
+        if ((centerInterval = Main.pref.getInteger(C_CENTER_INTERVAL, 0)) == 0)
+                centerInterval = DEFAULT_CENTER_INTERVAL;
+
+        Main.pref.putInteger(C_REFRESH_INTERVAL, refreshInterval);
+        Main.pref.putInteger(C_CENTER_INTERVAL, centerInterval);
     }
 }