Merge pull request #9 from raphaelmor/optimisation

Optimisation :  fixes #8

.gitignore

@@ -0,0 +1,27 @@
+# Xcode
+#
+.DS_Store
+build/
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata
+*.xccheckout
+*.moved-aside
+DerivedData
+*.hmap
+*.ipa
+*.xcuserstate
+
+# CocoaPods
+#
+# We recommend against adding the Pods directory to your .gitignore. However
+# you should judge for yourself, the pros and cons are mentioned at:
+# http://guides.cocoapods.org/using/using-cocoapods.html#should-i-ignore-the-pods-directory-in-source-control
+#
+# Pods/

Polyline.xcodeproj/project.pbxproj

@@ -332,6 +332,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
+				SWIFT_OBJC_BRIDGING_HEADER = "";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 			};
 			name = Debug;
@@ -349,6 +350,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
+				SWIFT_OBJC_BRIDGING_HEADER = "";
 			};
 			name = Release;
 		};

Polyline/Polyline.swift

@@ -149,43 +149,66 @@ public struct Polyline {
 
 	private func decodePolyline(encodedPolyline: String) -> Result<Array<CLLocationCoordinate2D>> {
 
-		var remainingPolyline = encodedPolyline.unicodeScalars
-		var decodedCoordinates = [CLLocationCoordinate2D]()
+        let data = encodedPolyline.dataUsingEncoding(NSUTF8StringEncoding)!
+
+        let byteArray = unsafeBitCast(data.bytes, UnsafePointer<Int8>.self)
+        let length = Int(data.length)
+        var position = Int(0)
+
+        var decodedCoordinates = [CLLocationCoordinate2D]()
+
+        var lat = 0.0
+        var lon = 0.0
+
+        while position < length {
+
+			let resultingLat = decodeSingleCoordinate(byteArray, length: length, position: &position)
+			if resultingLat.failed { return .Failure }
+            lat += resultingLat.value!
+
+			let resultingLon = decodeSingleCoordinate(byteArray, length: length, position: &position)
+			if resultingLat.failed { return .Failure }
+            lon += resultingLon.value!
+
+            decodedCoordinates.append(CLLocationCoordinate2D(latitude: lat, longitude: lon))
+        }
+
+        return .Success(decodedCoordinates)
+    }
+
+    private func decodeSingleCoordinate(byteArray: UnsafePointer<Int8>, length: Int, inout position: Int ) -> Result<Double> {
 
-		var lat = 0.0
-		var lon = 0.0
+        if position >= length {
+            return Result.Failure
+        }
 
-		while countElements(remainingPolyline) > 0 {
-			let latResult = extractNextChunk(&remainingPolyline)
-			if latResult.failed {
-				return .Failure
-			}
-			lat += decodeSingleCoordinate(latResult.value!)
-
-			let lonResult = extractNextChunk(&remainingPolyline)
-			if lonResult.failed {
-				return .Failure
-			}
-			lon += decodeSingleCoordinate(lonResult.value!)
-
-			decodedCoordinates.append(CLLocationCoordinate2D(latitude: lat, longitude: lon))
-		}
+        let bitMask = Int8(0x1F)
 
-		return .Success(decodedCoordinates)
-	}
-
-	private func decodeSingleCoordinate(value: String) -> Double {
-		let scalarArray = [] + value.unicodeScalars
+		var coordinate : Int32 = 0
 
-		var thirtyTwoBitNumber = agregateScalarArray(scalarArray)
-		// check if number is negative
-		if (thirtyTwoBitNumber & 0x1) == 0x1 {
-			thirtyTwoBitNumber = ~(thirtyTwoBitNumber >> 1)
-		} else {
-			thirtyTwoBitNumber = thirtyTwoBitNumber >> 1
+		var currentChar : Int8
+		var componentCounter : Int32 = 0
+		var component: Int32 = 0
+
+		do {
+			currentChar = byteArray[position] - 63
+			component = Int32(currentChar & bitMask)
+			coordinate |= (component << (5*componentCounter))
+			position++
+			componentCounter++
+		} while ((currentChar & 0x20) == 0x20) && (position < length) && (componentCounter < 6)
+
+		if (componentCounter == 6) && ((currentChar & 0x20) == 0x20) {
+			return Result.Failure
 		}
 
-		return Double(thirtyTwoBitNumber)/1e5
+        if (coordinate & 0x01) == 0x01 {
+            coordinate = ~(coordinate >> 1)
+        } else {
+            coordinate = coordinate >> 1
+        }
+
+        return Result.Success(Double(coordinate) / 100000.0)
 	}
 
 	// MARK:- Encoding levels

PolylineTests/PolylineTests.swift

@@ -237,6 +237,13 @@ class PolylineTests:XCTestCase {
 		let sut = Polyline(coordinates: sourceCoordinates)
 		XCTAssertEqual(sut.encodedPolyline, "_@~@")
 	}
+
+    // Github Issue 8
+    func testPerformances() {
+        self.measureBlock {
+            let sut = Polyline(encodedPolyline:"wamrIo{gnAnG_CVIm@{NEsDFgAHu@^{C`@sC@_As@eWEoBIw@?QDYd@oB@Uv@eDHOViAPwB@_ACUGQIcDYiIsA{a@EcB?iBD]JyBV}C@GJKDOCUMOO@MLy@@}ATI@McEQsLCcC?}@De@BQNe@gDcEgBsCSa@Yy@QiAS{D?gAJ_APmAt@wD`@eDDq@?aCk@uTcBif@KiBSkBa@wBUu@u@yB}CmHo@oAw@kA_@g@y@s@w@i@eJiF}BcB_BwAoCsDaB_DwLsWaBaDyB}Dm@qA_AcDEOIq@Sy@AuBBu@LgAR}@|@kCt@}Ab@s@^g@hAoAb@]jBkAdHqDt@[~@QxABNEHEdA}@TYbAyATQXKdC[n@Sr@c@r@}@|BwE~@eBjAyAvAaAlCaBlCoAjC_A|Cu@lLeBnDcAxBy@xDmBlEkCvDcCrFaEHGxAg@nAYf@Cz@@hCd@zAHj@MTIf@c@T]Zo@b@iBFo@DgA?k@CgAEa@Y_BoBeHo@sC{@iFg@qBk@aDqBeJaBcG}E_P{AsFq@kCk@eCwAmIm@yEk@cFg@eHU{FAiBMaIIiHImDSwF_@gGc@wFq@_G]aCc@yCcAsFiAeFCQ}FgUcEaRmBsJ_C}M_BaK{A{KsC_V_Gil@WqDy@kJk@eHyAeSu@mL]{Ha@kNI_GEkKFcV?mHKeHK}Cg@eKa@cFWmCm@}Ea@uCcCqMm@mCmAoEq@wBuA{DuAmD_BiDeDkG]u@{AwC{BaFiA_Dy@gCiA_Em@cCeAyEo@oDs@yEq@wFm@iHIyA]qIQiJIiBAkBDg@Ru@DOJSFc@Bc@AUIg@M[]aDIsAWyUs@cx@MqJ[wL_@gLg@uLo@oLiAkRo@_Iy@kH_@uCy@}Ey@mDaBcGkDsIgBkDgAaBiDiEkBqB}AkAmCaBaImDkAs@{BeBaBkBmBqCaCoEy@sBw@}Bq@aCoA{EeA_Fg@qCsAaJ_@sC]}CUqC_@qFIuAUkGQeIG}QCsRFuD?_CDgIAoJMyMUaLq@mO[wF}@uMe@oFc@kDu@wF{@{E_BwH[wAmDkL{HaToC}HwA{DiAkD_AuDyA_Ig@}Dg@wCyCiTi@cDy@qGcAeGkHyi@oAcJwBoPwAyJs@yFy@kFoFy_@wBeNkA}HcEuZeBqKOyAs@kEk@qEq@qE[cBWkBoAmHsBeOCQCuD\\{Bd@_Cz@aAbDuC~HuH|BsCjBqCdAgBrAgC~AwDjA{ClA}DrAmFf@_Cz@yE^aCh@_EVaCl@eHPcCp@qNbAuPf@_HtA}Nr@gG|@}GfAmHbB_JrAqG~AoItFkX`@_Cd@uDb@iEb@mFTiEXmJDyDAkDGeD]sIe@oG_A_Ko@gGaA{HwAyJi@eDqAoHiCiMmByH_EmOoCkIaGyR]_A}AcF_AiD}@_DwAiHc@oCa@kDa@gGQaEEwJFoD^}Ib@gF^kCZeCT}@x@oE\\yAtCaOb@iCv@qGV{CXwEJwE\\gh@RaMZsIv@iMX}CXyBnAeIj@qCx@cDrCkJrIeWdAmDp@mC`AsE\\gC~AeJTqBJq@VeDd@yH`@qMZaNx@c\\DaCDiAjAmc@f@iOjDwy@RqC|AcR|@}HtAiK~@oGn@oD|Hoa@vAwJ\\oCl@sGb@cF`@kHF_C`@iKJiH?gJIiDCoBo@yRsBga@[cREsFBeU`@sOTwGFeC~@cWf@wK~@_WbAu[vEmuAfAoXHiLHmTKe]GiCYoHY_Ew@aH}CmSwBkQgBcPw@uKScFCwCHeHZcIx@iOf@cMF}Bn@s^v@k\\n@i[j@aRNwGf@aPNsHb@kP|@yWp@wPLiFLqCbBej@?m@f@sQnAi_@b@mNlAg[VqE\\yELaCLuAdAmKXqB`@{D~BcTn@aGDm@NiATqC@i@F_BCeBOqDK}@e@yCAUDYBQFKn@Er@Bt@Jb@ApBS`CHfFIpEo@lFgB`FwC|@u@vCoCxA}AdEsG`CgFr@kBnAcE`BcHd@uCb@{Dj@kHNsCrAq`@T}ZFSFkAR_BBQDIrBwB|Ca@fGKhADbLfBlD`AhCz@pExBtBpAxCtBt@b@dBr@|@TjBTnBCbAK^IxCeAp@]xC}Bv@u@rCuDxSo\\jBsCfnAgnB|TiZjD}Df@a@bD{BpDsBfIyCvh@yXzB}@pAYnEi@tGArD}@nOsFxJuFjLeIvF}C`GkEtBmA|AUn@AdQP~Fo@zBNtO~B`CV`@@b@I~@o@d@i@|@gB`IeT|C{Ib@aB^iB~DmS`AsD~@eCb@_AXe@lBmCjd@m`@rJcIxKgKbEcDzQmS|CyCfDiCbDmBjBy@tEaBfIqAnQmBbA[|AY|EgBdF_CxH_GtAmAbDsDd@o@|e@mt@vCaEhHqIbL{KvF}DrNmJl@El@c@v@g@\\s@~@o@tG_E\\AbEiCZe@dB}@hGsA^EdCBfC[zNy@`Di@fAM`@Mz@_@~UcIdHcB~CWdACx]nAnFl@pBh@fEvBjRfKrP~IvGlCfB\\rF^n@@~AKpC]fYeH`@EfECrDZ`Ej@xFp@rBFtBErAKnCe@~Ae@lBu@~HcEjF{BpJkDzJaDpCmAtDiC|BqBhEaFbCeCXChBuApBcAb@EJ@RBPEFQh@a@pBq@R@RJL@H?Jd@Xf@TFNATONSDKz@o@XMp@OTMpBUfAQjDoA|BwAv@o@j@]~A_BtIyJtEcGpC_EHKLNNEDKBOC[tDqFtAaBt@u@jAeAfBuALKfA_BjDoEfDiC~@a@BCYyDYsBCQz@aAHIP~@")
+        }
+    }
 
 	// MARK:- README code samples