Show blue contraflow arrow for oneway:bicycle=no on one-way ways

src/Shared/EditorLayer/EditorMapLayer.swift

@@ -608,7 +608,7 @@ final class EditorMapLayer: CALayer {
 		alongScreenClippedWay way: OsmWay,
 		offset initialOffset: Double,
 		interval: Double,
-		block: @escaping (_ pt: OSMPoint, _ direction: OSMPoint) -> Void)
+		block: @escaping (_ pt: OSMPoint, _ direction: OSMPoint, _ offsetAlongSegment: Double, _ segmentLength: Double) -> Void)
 	{
 		var offset = initialOffset
 		invoke(alongScreenClippedWay: way, block: { p1, p2, isEntry, _ in
@@ -624,14 +624,65 @@ final class EditorMapLayer: CALayer {
 				// found it
 				let pos = OSMPoint(x: p1.x + offset * dx, y: p1.y + offset * dy)
 				let dir = OSMPoint(x: dx, y: dy)
-				block(pos, dir)
+				block(pos, dir, offset, len)
 				offset += interval
 			}
 			offset -= len
 			return true
 		})
 	}
 
+	private static let oneWayArrowChevronLength: Double = 15
+	private static let oneWayArrowChevronWidth: Double = 5
+	/// Along-way distance from motor chevron tip to bicycle chevron tip (motor icon + gap + bicycle icon).
+	private static let bicycleContraflowArrowLongitudinalOffset: Double = 3 * oneWayArrowChevronLength
+
+	private static func canPlaceBicycleContraflowArrow(
+		behindAlongWay: Double,
+		offsetAlongSegment: Double,
+		segmentLength: Double
+	) -> Bool {
+		if behindAlongWay < 0 {
+			return offsetAlongSegment >= bicycleContraflowArrowLongitudinalOffset
+		}
+		return (segmentLength - offsetAlongSegment) >= bicycleContraflowArrowLongitudinalOffset
+	}
+
+	private func makeOneWayArrowLayer(
+		at loc: OSMPoint,
+		direction dir: OSMPoint,
+		chevronLength len: Double,
+		alongWayOffset: Double,
+		fillColor: UIColor,
+		zPosition: CGFloat
+	) -> CAShapeLayerWithProperties {
+		let position = OSMPoint(x: loc.x + dir.x * alongWayOffset,
+		                        y: loc.y + dir.y * alongWayOffset)
+		let width = Self.oneWayArrowChevronWidth
+
+		let p1 = OSMPoint(x: position.x - dir.x * len + dir.y * width,
+		                  y: position.y - dir.y * len - dir.x * width)
+		let p2 = OSMPoint(x: position.x - dir.x * len - dir.y * width,
+		                  y: position.y - dir.y * len + dir.x * width)
+
+		let arrowPath = CGMutablePath()
+		arrowPath.move(to: CGPoint(x: p1.x, y: p1.y))
+		arrowPath.addLine(to: CGPoint(x: position.x, y: position.y))
+		arrowPath.addLine(to: CGPoint(x: p2.x, y: p2.y))
+		arrowPath
+			.addLine(to: CGPoint(x: CGFloat(position.x - dir.x * len * 0.5),
+			                     y: CGFloat(position.y - dir.y * len * 0.5)))
+		arrowPath.closeSubpath()
+
+		let arrow = CAShapeLayerWithProperties()
+		arrow.path = arrowPath
+		arrow.fillColor = fillColor.cgColor
+		arrow.strokeColor = UIColor.white.cgColor
+		arrow.lineWidth = 0.5
+		arrow.zPosition = zPosition
+		return arrow
+	}
+
 	// clip a way to the path inside the viewable rect so we can draw a name on it
 	func pathClipped(toViewRect way: OsmWay, length pLength: UnsafeMutablePointer<CGFloat>?) -> CGPath? {
 		var path: CGMutablePath?
@@ -1409,36 +1460,36 @@ final class EditorMapLayer: CALayer {
 			}
 			let isHighlight = highlights.contains(way)
 			if way.isOneWay != .NONE || isHighlight {
+				let showBicycleContraflow = way.allowsBicycleContraflow()
+				let arrowZ = isHighlight ? self.Z_HIGHLIGHT_ARROW : self.Z_ARROW
 				// arrow heads
-				invoke(alongScreenClippedWay: way, offset: 50, interval: 100, block: { loc, dir in
-					// draw direction arrow at loc/dir
-					let reversed = way.isOneWay == ONEWAY.BACKWARD
-					let len: Double = reversed ? -15 : 15
-					let width: Double = 5
-
-					let p1 = OSMPoint(x: loc.x - dir.x * len + dir.y * width,
-					                  y: loc.y - dir.y * len - dir.x * width)
-					let p2 = OSMPoint(x: loc.x - dir.x * len - dir.y * width,
-					                  y: loc.y - dir.y * len + dir.x * width)
-
-					let arrowPath = CGMutablePath()
-					arrowPath.move(to: CGPoint(x: p1.x, y: p1.y))
-					arrowPath.addLine(to: CGPoint(x: loc.x, y: loc.y))
-					arrowPath.addLine(to: CGPoint(x: p2.x, y: p2.y))
-					arrowPath
-						.addLine(to: CGPoint(x: CGFloat(loc.x - dir.x * len * 0.5),
-						                     y: CGFloat(loc.y - dir.y * len * 0.5)))
-					arrowPath.closeSubpath()
-
-					let arrow = CAShapeLayerWithProperties()
-					arrow.path = arrowPath
-					arrow.lineWidth = 1
-					arrow.fillColor = UIColor.black.cgColor
-					arrow.strokeColor = UIColor.white.cgColor
-					arrow.lineWidth = 0.5
-					arrow.zPosition = isHighlight ? self.Z_HIGHLIGHT_ARROW : self.Z_ARROW
-
-					layers.append(arrow)
+				invoke(alongScreenClippedWay: way, offset: 50, interval: 100, block: { loc, dir, offsetAlongSegment, segmentLength in
+					let motorLen = way.isOneWay == .BACKWARD
+						? -Self.oneWayArrowChevronLength
+						: Self.oneWayArrowChevronLength
+					if showBicycleContraflow {
+						let behindAlongWay = way.isOneWay == .FORWARD
+							? -Self.bicycleContraflowArrowLongitudinalOffset
+							: Self.bicycleContraflowArrowLongitudinalOffset
+						if Self.canPlaceBicycleContraflowArrow(
+							behindAlongWay: behindAlongWay,
+							offsetAlongSegment: offsetAlongSegment,
+							segmentLength: segmentLength)
+						{
+							layers.append(self.makeOneWayArrowLayer(at: loc,
+							                                        direction: dir,
+							                                        chevronLength: -motorLen,
+							                                        alongWayOffset: behindAlongWay,
+							                                        fillColor: UIColor.systemBlue,
+							                                        zPosition: arrowZ))
+						}
+					}
+					layers.append(self.makeOneWayArrowLayer(at: loc,
+					                                          direction: dir,
+					                                          chevronLength: motorLen,
+					                                          alongWayOffset: 0,
+					                                          fillColor: UIColor.black,
+					                                          zPosition: arrowZ))
 				})
 			}
 

src/Shared/OSMModels/OsmWay.swift

@@ -270,6 +270,15 @@ final class OsmWay: OsmBaseObject, NSSecureCoding {
 		return _isOneWay!
 	}
 
+	// https://wiki.openstreetmap.org/wiki/Key:oneway:bicycle
+	/// True when the way is one-way for general traffic but cyclists may use the opposite direction.
+	func allowsBicycleContraflow() -> Bool {
+		guard isOneWay != .NONE else {
+			return false
+		}
+		return tags["oneway:bicycle"] == "no"
+	}
+
 	// return the point on the way closest to the supplied point
 	override func latLonOnObject(forLatLon target: LatLon) -> LatLon {
 		switch nodes.count {

src/iOS/Go Map!!.xcodeproj/project.pbxproj

@@ -231,6 +231,7 @@
 		64348CFE225E867800ADE7FB /* MeasureDirectionViewModelTestCase.swift in Sources */ = {isa = PBXBuildFile; fileRef = 64348CFA225E867800ADE7FB /* MeasureDirectionViewModelTestCase.swift */; };
 		64348D01225E8D3F00ADE7FB /* OsmNode+Direction.swift in Sources */ = {isa = PBXBuildFile; fileRef = 64348D00225E8D3F00ADE7FB /* OsmNode+Direction.swift */; };
 		64348D03225E8E4300ADE7FB /* OsmNode_DirectionTestCase.swift in Sources */ = {isa = PBXBuildFile; fileRef = 64348D02225E8E4300ADE7FB /* OsmNode_DirectionTestCase.swift */; };
+		64348D15225E8E4300ADE7FB /* OsmWay_BicycleContraflowTestCase.swift in Sources */ = {isa = PBXBuildFile; fileRef = 64348D14225E8E4300ADE7FB /* OsmWay_BicycleContraflowTestCase.swift */; };
 		64348D13225EAA5D00ADE7FB /* MapViewUITestCase.swift in Sources */ = {isa = PBXBuildFile; fileRef = 64348D12225EAA5D00ADE7FB /* MapViewUITestCase.swift */; };
 		6442666722540EDF00C0D545 /* Lock.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6442666422540EDF00C0D545 /* Lock.swift */; };
 		6442666822540EDF00C0D545 /* Disposable.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6442666522540EDF00C0D545 /* Disposable.swift */; };
@@ -591,6 +592,7 @@
 		64348CFA225E867800ADE7FB /* MeasureDirectionViewModelTestCase.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MeasureDirectionViewModelTestCase.swift; sourceTree = "<group>"; };
 		64348D00225E8D3F00ADE7FB /* OsmNode+Direction.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "OsmNode+Direction.swift"; sourceTree = "<group>"; };
 		64348D02225E8E4300ADE7FB /* OsmNode_DirectionTestCase.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OsmNode_DirectionTestCase.swift; sourceTree = "<group>"; };
+		64348D14225E8E4300ADE7FB /* OsmWay_BicycleContraflowTestCase.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OsmWay_BicycleContraflowTestCase.swift; sourceTree = "<group>"; };
 		64348D08225EA24E00ADE7FB /* GoMapUITests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = GoMapUITests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		64348D0C225EA24E00ADE7FB /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		64348D12225EAA5D00ADE7FB /* MapViewUITestCase.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MapViewUITestCase.swift; sourceTree = "<group>"; };
@@ -1188,6 +1190,7 @@
 				64348CFA225E867800ADE7FB /* MeasureDirectionViewModelTestCase.swift */,
 				64348CF6225E867800ADE7FB /* Mocks */,
 				64348D02225E8E4300ADE7FB /* OsmNode_DirectionTestCase.swift */,
+				64348D14225E8E4300ADE7FB /* OsmWay_BicycleContraflowTestCase.swift */,
 				64348CEC225E7CD900ADE7FB /* GoMapTests.swift */,
 				64C072FC22622B9C00598078 /* Vendor */,
 				64348CEE225E7CD900ADE7FB /* Info.plist */,
@@ -1815,6 +1818,7 @@
 				64E21EB822651F2D004605D7 /* XCTestCase+UserDefaults.swift in Sources */,
 				64348CFD225E867800ADE7FB /* CLHeadingMock.swift in Sources */,
 				64348D03225E8E4300ADE7FB /* OsmNode_DirectionTestCase.swift in Sources */,
+				64348D15225E8E4300ADE7FB /* OsmWay_BicycleContraflowTestCase.swift in Sources */,
 				64E21EB522651C06004605D7 /* OSMMapDataTestCase.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

src/iOS/GoMapTests/OsmWay_BicycleContraflowTestCase.swift

@@ -0,0 +1,39 @@
+//
+//  OsmWay_BicycleContraflowTestCase.swift
+//  GoMapTests
+//
+
+@testable import Go_Map__
+import XCTest
+
+class OsmWay_BicycleContraflowTestCase: XCTestCase {
+	func testAllowsBicycleContraflowWhenOneWayAndOnewayBicycleNo() {
+		let way = OsmWay(asUserCreated: "")
+		way.constructTag("oneway", value: "yes")
+		way.constructTag("oneway:bicycle", value: "no")
+
+		XCTAssertTrue(way.allowsBicycleContraflow())
+	}
+
+	func testAllowsBicycleContraflowWhenOneWayBackwardAndOnewayBicycleNo() {
+		let way = OsmWay(asUserCreated: "")
+		way.constructTag("oneway", value: "-1")
+		way.constructTag("oneway:bicycle", value: "no")
+
+		XCTAssertTrue(way.allowsBicycleContraflow())
+	}
+
+	func testDoesNotAllowBicycleContraflowWithoutOnewayBicycleNo() {
+		let way = OsmWay(asUserCreated: "")
+		way.constructTag("oneway", value: "yes")
+
+		XCTAssertFalse(way.allowsBicycleContraflow())
+	}
+
+	func testDoesNotAllowBicycleContraflowWhenNotOneWay() {
+		let way = OsmWay(asUserCreated: "")
+		way.constructTag("oneway:bicycle", value: "no")
+
+		XCTAssertFalse(way.allowsBicycleContraflow())
+	}
+}