integrated nite overlay

Author: rossengeorgiev

build.sh

@@ -19,6 +19,7 @@ cat jquery* iscroll.js >> mobile.js
 
 # compile the rest
 java -jar "../tools/yuicompressor-2.4.8pre.jar" --type=js --disable-optimizations --nomunge chasecar.lib.js >> mobile.js
+java -jar "../tools/yuicompressor-2.4.8pre.jar" --type=js --disable-optimizations --nomunge nite-overlay.js >> mobile.js
 java -jar "../tools/yuicompressor-2.4.8pre.jar" --type=js --disable-optimizations --nomunge tracker.js >> mobile.js
 java -jar "../tools/yuicompressor-2.4.8pre.jar" --type=js --disable-optimizations --nomunge app.js >> mobile.js
 

index.html

@@ -104,6 +104,7 @@ <h2>Chase car mode</h2>
     <script type="text/javascript" language="javascript" src="js/jquery-1.8.3-min.js"></script>
     <script type="text/javascript" language="javascript" src="js/chasecar.lib.js"></script>
     <script type="text/javascript" language="javascript" src="js/iscroll.js"></script>
+    <script type="text/javascript" language="javascript" src="js/nite-overlay.js"></script>
     <script type="text/javascript" language="javascript" src="js/tracker.js"></script>
     <script type="text/javascript" language="javascript" src="js/app.js"></script>
 -->

js/mobile.js

@@ -0,0 +1,91 @@
+/* Nite v1.0
+ * A tiny library to create a night overlay over the map
+ * Author: Rossen Georgiev @ https://github.com/rossengeorgiev
+ * Requires: GMaps API 3
+ */
+
+
+var nite = {
+    map: null,
+    marker_sun: null,
+    marker_shadow: null,
+    marker_shadow_lite: null,
+    shadow_radius: parseInt(6371 * Math.PI * 500),
+    sun_position: null,
+
+    init: function(map) {  
+        if(typeof google === 'undefined'
+           || typeof google.maps === 'undefined') throw "Nite Overlay: no google.maps detected";
+        
+        this.map = map;
+        this.refreshSunZenith();
+        
+        this.marker_shadow = new google.maps.Circle({
+            map: this.map,
+            center: this.getShadowPosition(),
+            radius: this.shadow_radius,
+            fillColor: "#000",
+            fillOpacity: 0.1,
+            strokeOpacity: 0,
+            clickable: false,
+            editable: false 
+        }); 
+
+        this.marker_shadow_lite = new google.maps.Circle({
+            map: this.map,
+            center: this.getShadowPosition(),
+            radius: this.shadow_radius * 0.96,
+            fillColor: "#000",
+            fillOpacity: 0.1,
+            strokeOpacity: 0,
+            clickable: false,
+            editable: false 
+        }); 
+    },
+    getShadowPosition: function() {
+        return new google.maps.LatLng(-this.sun_position.lat(), -this.sun_position.lng() + 180);
+    },
+    refresh: function() {
+        this.refreshSunZenith();
+        this.marker_shadow.setCenter(this.getShadowPosition());
+        this.marker_shadow_lite.setCenter(this.getShadowPosition());
+    },
+    refreshSunZenith: function() {
+        var rad = 0.017453292519943295;
+
+        // based on NOAA solar calculations
+        var utc = new Date();
+        utc = new Date(utc.getTime() + utc.getTimezoneOffset() * 60000);
+        var mins_past_midnight = (utc.getHours() * 60 + utc.getMinutes()) / 1440;
+        var jd = 2415018.5 - ((new Date("01/01/1900 00:00:00 UTC")).getTime() - utc.getTime()) / 1000 / 60 / 60 / 24;
+        var jc = (jd - 2451545)/36525;
+        var mean_long_sun = (280.46646+jc*(36000.76983+jc*0.0003032)) % 360;
+        var mean_anom_sun = 357.52911+jc*(35999.05029-0.0001537*jc);
+        var sun_eq = Math.sin(rad*mean_anom_sun)*(1.914602-jc*(0.004817+0.000014*jc))+Math.sin(rad*2*mean_anom_sun)*(0.019993-0.000101*jc)+Math.sin(rad*3*mean_anom_sun)*0.000289;
+        var sun_true_long = mean_long_sun + sun_eq;
+        var sun_app_long = sun_true_long - 0.00569 - 0.00478*Math.sin(rad*125.04-1934.136*jc);
+        var mean_obliq_ecliptic = 23+(26+((21.448-jc*(46.815+jc*(0.00059-jc*0.001813))))/60)/60;
+        var obliq_corr = mean_obliq_ecliptic + 0.00256*Math.cos(rad*125.04-1934.136*jc);
+        
+        var lat = Math.asin(Math.sin(rad*obliq_corr)*Math.sin(rad*sun_app_long)) / rad;
+
+        var eccent = 0.016708634-jc*(0.000042037+0.0000001267*jc);
+        var y = Math.tan(rad*(obliq_corr/2))*Math.tan(rad*(obliq_corr/2));
+        var rq_of_time = 4*((y*Math.sin(2*rad*mean_long_sun)-2*eccent*Math.sin(rad*mean_anom_sun)+4*eccent*y*Math.sin(rad*mean_anom_sun)*Math.cos(2*rad*mean_long_sun)-0.5*y*y*Math.sin(4*rad*mean_long_sun)-1.25*eccent*eccent*Math.sin(2*rad*mean_anom_sun))/rad);
+        var true_solar_time = (mins_past_midnight*1440+rq_of_time) % 1440;
+        var lng = (true_solar_time/4 < 0) ? true_solar_time/4 + 180 : true_solar_time/4 - 180;
+
+        this.sun_position = new google.maps.LatLng(lat, lng);
+    },
+    setMap: function(map) {
+        this.map = map;        
+    },
+    show: function() {
+        this.marker_shadow.setVisible(true); 
+        this.marker_shadow_lite.setVisible(true); 
+    },
+    hide: function() {
+        this.marker_shadow.setVisible(false); 
+        this.marker_shadow_lite.setVisible(false); 
+    }
+}

js/nite-overlay.js

@@ -50,6 +50,9 @@ function load() {
         zoomContro: true,
         scrollwheel: true
     });
+    
+    nite.init(map);
+    setInterval(function() { nite.refresh(); }, 300000); // 5min
 
     // we need a dummy overlay to access getProjection()	
     overlay = new google.maps.OverlayView();