#20 implemented forward pick optimization

gyuque · Jan 31, 2014 · bc5498b · bc5498b
1 parent 715a4de
commit bc5498b
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Showing 3 changed files with 29 additions and 8 deletions.
diff --git a/inner/js/data/moving-data.js b/inner/js/data/moving-data.js
@@ -223,6 +223,9 @@ if (!window.mobmap) window.mobmap={};
 	function TimeList(objId) {
 		this.id = objId;
 		this.recordList = [];
+
+		this.cahcedIndex = -1;
+		this.cahcedTime  = -1;
 	}
 
 	TimeList.prototype = {
@@ -237,9 +240,15 @@ if (!window.mobmap) window.mobmap={};
 		pickAt: function(pickPool, pickedRec, seconds, extraProps, pickIndex) {
 			var ls = this.recordList;
 			var len = ls.length;
-
+			var startIndex = 0;
+
+			// Forward pick optimization
+			if (this.cahcedIndex >= 0 && this.cahcedTime < seconds) {
+				startIndex = this.cahcedIndex;
+			}
+
 			var i, previ = -1;
-			for (i = 0;i < len;++i) {
+			for (i = startIndex;i < len;++i) {
 				var rec = ls[i];
 				if (rec._time > seconds) {
 					break;
@@ -249,6 +258,10 @@ if (!window.mobmap) window.mobmap={};
 			if (len > 0) {
 				if (i > 0) {
 					previ = i - 1;
+
+					// Update fwd-pick cache
+					this.cahcedIndex = previ;
+					this.cahcedTime  = ls[previ]._time;
 				}
 
 				// Set output record object if null

diff --git a/js/moving-data-2.js b/js/moving-data-2.js
@@ -175,13 +175,17 @@ if (!window.mobmap) window.mobmap={};
 		pickAt: function(pickPool, pickedRec, seconds, extraProps, pickIndex) {
 			var ls = this.recordList;
 			var len = ls.length;
-			var prevTime = -1;
+			var startIndex = 0;
+
+			// Forward pick optimization
+			if (this.cahcedIndex >= 0 && this.cahcedTime < seconds) {
+				startIndex = this.cahcedIndex;
+			}
 
 			var i, previ = -1;
-			for (i = 0;i < len;++i) {
+			for (i = startIndex;i < len;++i) {
 				var rec = ls[i];
-				prevTime = rec._time;
-				if (prevTime > seconds) {
+				if (rec._time > seconds) {
 					break;
 				}
 			}
@@ -190,6 +194,10 @@ if (!window.mobmap) window.mobmap={};
 			if (len > 0) {
 				if (i > 0) {
 					previ = i - 1;
+
+					// Update fwd-pick cache
+					this.cahcedIndex = previ;
+					this.cahcedTime  = ls[previ]._time;
 				}
 
 				// Set output record object if null

diff --git a/js/picker-test.js b/js/picker-test.js
@@ -49,8 +49,8 @@
 		var mdat = testMovingData;
 
 		var tStart = new Date();
-		for (var i = 0;i < 10;++i) {
-			var pickTime = dataMinSec + 3600 * i + 1800;
+		for (var i = 0;i < 19;++i) {
+			var pickTime = dataMinSec + 1800 * i + 1800;
 			//var pickTime = dataMinSec + 6;
 
 			mdPickPool.clear();