feat: new protocol for chained functions, and added support for expli… (#252)

* feat: new protocol for chained functions, and added support for explicit Y ranges. X coming as well

* feat: add new axis interface (#253)

Sources/SwiftUICharts/Base/Chart/ChartData.swift

@@ -41,19 +41,11 @@ public class ChartData: ObservableObject {
     }
 
     var normalisedYRange: Double {
-        if let _ = rangeY {
-            return 1
-        }
-
-        return (normalisedPoints.max() ?? 0.0) - (normalisedPoints.min() ?? 0.0)
+        return rangeY == nil ? (normalisedPoints.max() ?? 0.0) - (normalisedPoints.min() ?? 0.0) : 1
     }
 
     var normalisedXRange: Double {
-        if let _ = rangeX {
-            return 1
-        }
-
-        return (normalisedValues.max() ?? 0.0) - (normalisedValues.min() ?? 0.0)
+        return rangeX == nil ? (normalisedValues.max() ?? 0.0) - (normalisedValues.min() ?? 0.0) : 1
     }
 
     var isInNegativeDomain: Bool {

Sources/SwiftUICharts/Base/Extensions/Path+QuadCurve.swift

@@ -201,7 +201,7 @@ extension Path {
         let convertedXValues = data.map { CGFloat($0.0) * rect.width }
         let convertedYPoints = data.map { CGFloat($0.1) * rect.height }
 
-        path.move(to: .zero)
+        path.move(to: CGPoint(x: convertedXValues[0], y: 0))
         var point1 = CGPoint(x: convertedXValues[0], y: convertedYPoints[0])
         path.addLine(to: point1)
         for pointIndex in 1..<data.count {

Sources/SwiftUICharts/Base/Extensions/View+Extension.swift

@@ -8,4 +8,10 @@ extension View {
     public func chartStyle(_ style: ChartStyle) -> some View {
         self.environmentObject(style)
     }
+
+    public func toStandardCoordinateSystem() -> some View {
+        self
+            .rotationEffect(.degrees(180), anchor: .center)
+            .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+    }
 }

Sources/SwiftUICharts/Base/Grid/ChartGridShape.swift

@@ -17,13 +17,11 @@ struct ChartGridShape_Previews: PreviewProvider {
         Group {
             ChartGridShape(numberOfHorizontalLines: 5, numberOfVerticalLines: 0)
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
 
             ChartGridShape(numberOfHorizontalLines: 4, numberOfVerticalLines: 4)
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
         }
         .padding()
     }

Sources/SwiftUICharts/Charts/LineChart/Line.swift

@@ -43,8 +43,7 @@ public struct Line: View {
                     IndicatorPoint()
                         .position(self.getClosestPointOnPath(geometry: geometry,
                                                              touchLocation: self.touchLocation))
-                        .rotationEffect(.degrees(180), anchor: .center)
-                        .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                        .toStandardCoordinateSystem()
                 }
             }
             .onAppear {

Sources/SwiftUICharts/Charts/LineChart/LineBackgroundShape.swift

@@ -14,14 +14,12 @@ struct LineBackgroundShape_Previews: PreviewProvider {
             GeometryReader { geometry in
                 LineBackgroundShape(data: [(0, -0.5), (0.25, 0.8), (0.5,-0.6), (0.75,0.6), (1, 1)])
                     .fill(Color.red)
-                    .rotationEffect(.degrees(180), anchor: .center)
-                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                    .toStandardCoordinateSystem()
             }
             GeometryReader { geometry in
                 LineBackgroundShape(data: [(0, 0), (0.25, 0.5), (0.5,0.8), (0.75, 0.6), (1, 1)])
                     .fill(Color.blue)
-                    .rotationEffect(.degrees(180), anchor: .center)
-                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                    .toStandardCoordinateSystem()
             }
         }
     }

Sources/SwiftUICharts/Charts/LineChart/LineBackgroundShapeView.swift

@@ -11,7 +11,6 @@ struct LineBackgroundShapeView: View {
                                                              backgroundColor.endColor]),
                                  startPoint: .bottom,
                                  endPoint: .top))
-            .rotationEffect(.degrees(180), anchor: .center)
-            .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+            .toStandardCoordinateSystem()
     }
 }

Sources/SwiftUICharts/Charts/LineChart/LineShape.swift

@@ -20,13 +20,11 @@ struct LineShape_Previews: PreviewProvider {
         Group {
             LineShape(data: [(0, 0), (0.25, 0.5), (0.5,0.8), (0.75, 0.6), (1, 1)])
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
 
             LineShape(data: [(0, -0.5), (0.25, 0.8), (0.5,-0.6), (0.75,0.6), (1, 1)], lineStyle: .straight)
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
         }
     }
 }

Sources/SwiftUICharts/Charts/LineChart/LineShapeView.swift

@@ -31,8 +31,7 @@ struct LineShapeView: View, Animatable {
                                        startPoint: .leading,
                                        endPoint: .trailing),
                         style: StrokeStyle(lineWidth: chartProperties.lineWidth, lineJoin: .round))
-                .rotationEffect(.degrees(180), anchor: .center)
-                .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
                 .clipped()
             if chartProperties.showChartMarks {
                 MarkerShape(data: chartData.normalisedData)
@@ -40,8 +39,7 @@ struct LineShapeView: View, Animatable {
                     .fill(.white,
                           strokeBorder: chartMarkColor,
                           lineWidth: chartProperties.lineWidth)
-                    .rotationEffect(.degrees(180), anchor: .center)
-                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                    .toStandardCoordinateSystem()
             }
         }
     }

Sources/SwiftUICharts/Charts/LineChart/MarkerShape.swift

@@ -13,13 +13,11 @@ struct MarkerShape_Previews: PreviewProvider {
         Group {
             MarkerShape(data: [(0, 0), (0.25, 0.5), (0.5,0.8), (0.75, 0.6), (1, 1)])
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
 
             MarkerShape(data: [(0, -0.5), (0.25, 0.8), (0.5,-0.6), (0.75,0.6), (1, 1)])
                 .stroke()
-                .rotationEffect(.degrees(180), anchor: .center)
-                                    .rotation3DEffect(.degrees(180), axis: (x: 0, y: 1, z: 0))
+                .toStandardCoordinateSystem()
         }
     }
 }