Make stroke caps configurable for radial gauge and radial value bars.

lib/src/radial_gauge/radial_gauge.dart

@@ -41,6 +41,7 @@ class RadialGauge extends StatefulWidget {
     this.shapePointer = const [],
     this.needlePointer = const [],
     this.widgetPointer = const [],
+    this.strokeCap = StrokeCap.round,
     // List<RadialTrack>? track,
   }) : super(key: key);
 
@@ -173,6 +174,13 @@ class RadialGauge extends StatefulWidget {
   ///
   final List<RadialValueBar>? valueBar;
 
+  ///
+  /// The stroke cap of the radial gauge container.
+  ///
+  /// Defaults to StrokeCap.round.
+  ///
+  final StrokeCap strokeCap;
+
   @override
   State<RadialGauge> createState() => _RadialGaugeState();
 }

lib/src/radial_gauge/radial_gauge_container_painter.dart

@@ -192,14 +192,14 @@ class RenderRadialGaugeContainer extends RenderBox {
     // double radialOffset = getRadialGauge.valueBar!.first.radialOffset;
 
     double partAngle = arcLength / numParts; // angle of each part in radians
-    double radius = (shortestSide / 2 - thickness) *
+    double radius = (shortestSide / 2.0 - thickness / 2.0) *
         getRadialGauge.radiusFactor; // radius of the arc
 
     final center = offset;
 
     final Paint containerPaint = Paint()
       ..color = getRadialGauge.track.color
-      ..strokeCap = StrokeCap.round
+      ..strokeCap = getRadialGauge.strokeCap
       ..strokeWidth = thickness
       ..style = PaintingStyle.stroke;
 

lib/src/radial_gauge/valuebar/radial_value_bar.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:geekyants_flutter_gauges/geekyants_flutter_gauges.dart';
 import 'package:geekyants_flutter_gauges/src/radial_gauge/valuebar/radial_value_bar_painter.dart';
+
 import '../radial_gauge.dart';
 import '../radial_gauge_state.dart';
 
@@ -36,6 +37,7 @@ class RadialValueBar extends LeafRenderObjectWidget {
     this.valueBarThickness = 10,
     this.gradient,
     this.radialOffset = 0,
+    this.strokeCap = StrokeCap.round,
   }) : super(key: key);
 
   /// [value] denotes the value of the value bar.
@@ -123,6 +125,10 @@ class RadialValueBar extends LeafRenderObjectWidget {
   ///
   final LinearGradient? gradient;
 
+  /// [strokeCap] denotes the stroke cap of the value bar.
+  ///
+  final StrokeCap strokeCap;
+
   @override
   RenderObject createRenderObject(BuildContext context) {
     final RadialGaugeState scope = RadialGaugeState.of(context);
@@ -133,6 +139,7 @@ class RadialValueBar extends LeafRenderObjectWidget {
       gradient: gradient ?? LinearGradient(colors: [color, color]),
       radialOffset: radialOffset,
       valueBarThickness: valueBarThickness,
+      strokeCap: strokeCap,
       radialGauge: scope.rGauge,
     );
   }
@@ -147,6 +154,7 @@ class RadialValueBar extends LeafRenderObjectWidget {
       ..setRadialOffset = radialOffset
       ..setLinearGradient = gradient ?? LinearGradient(colors: [color, color])
       ..setValueBarThickness = valueBarThickness
-      ..setRadialGauge = scope.rGauge;
+      ..setRadialGauge = scope.rGauge
+      ..setStrokeCap = strokeCap;
   }
 }

lib/src/radial_gauge/valuebar/radial_value_bar_painter.dart

@@ -1,5 +1,7 @@
 import 'dart:math';
+
 import 'package:flutter/rendering.dart';
+
 import '../../../geekyants_flutter_gauges.dart';
 
 class RenderRadialValueBar extends RenderBox {
@@ -11,12 +13,14 @@ class RenderRadialValueBar extends RenderBox {
     required double valueBarThickness,
     required RadialGauge radialGauge,
     required double radialOffset,
+    required StrokeCap strokeCap,
   })  : _value = value,
         _color = color,
         _gradient = gradient!,
         _radialOffset = radialOffset,
         _radialGauge = radialGauge,
         _valueBarThickness = valueBarThickness,
+        _strokeCap = strokeCap,
         super();
 
   RadialGauge get getRadialGauge => _radialGauge!;
@@ -59,6 +63,14 @@ class RenderRadialValueBar extends RenderBox {
     markNeedsPaint();
   }
 
+  StrokeCap get getStrokeCap => _strokeCap;
+  StrokeCap _strokeCap;
+  set setStrokeCap(StrokeCap strokeCap) {
+    if (_strokeCap == strokeCap) return;
+    _strokeCap = strokeCap;
+    markNeedsPaint();
+  }
+
   LinearGradient get getLinearGradient => _gradient;
   LinearGradient _gradient;
   set setLinearGradient(LinearGradient linearGradient) {
@@ -107,7 +119,7 @@ class RenderRadialValueBar extends RenderBox {
 
     final Paint containerPaint = Paint()
       ..color = _color
-      ..strokeCap = StrokeCap.round
+      ..strokeCap = _strokeCap
       ..strokeWidth = _valueBarThickness
       ..shader = gradient.createShader(
           Rect.fromCircle(center: center, radius: size.shortestSide / 2.0))
@@ -116,7 +128,7 @@ class RenderRadialValueBar extends RenderBox {
     double arcLength = endAngle - startAngle;
     double shortestSide = size.shortestSide;
     double radius = (shortestSide / 2.0 -
-            getRadialGauge.track.thickness -
+            getRadialGauge.track.thickness / 2.0 -
             getRadialOffset) *
         getRadialGauge.radiusFactor;