Fix issue hard coded values in radial widget painter

example/lib/radial_gauge_custom_widget.dart

@@ -0,0 +1,40 @@
+import 'package:flutter/material.dart';
+import 'package:geekyants_flutter_gauges/geekyants_flutter_gauges.dart';
+
+///
+/// The following code  is a Simple Example of [RadialGauge] Widget with custom widgets.
+///
+class RadialGaugeCustomWidget extends StatefulWidget {
+  const RadialGaugeCustomWidget({super.key});
+
+  @override
+  State<RadialGaugeCustomWidget> createState() =>
+      _RadialGaugeCustomWidgetState();
+}
+
+class _RadialGaugeCustomWidgetState extends State<RadialGaugeCustomWidget> {
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      backgroundColor: Colors.white,
+      body: RadialGauge(
+        track: RadialTrack(
+          color: Colors.grey,
+          start: 0,
+          end: 100,
+          thickness: 40,
+        ),
+        widgetPointer: [
+          RadialWidgetPointer(
+            value: 35.5,
+            child: Text("35.5"),
+          ),
+          RadialWidgetPointer(
+            value: 78.2,
+            child: Text("78.2"),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/src/radial_gauge/pointer/radial_widget_painter.dart

@@ -70,24 +70,32 @@ class RenderRadialWidgetPointer extends RenderProxyBox {
     double gaugeStart = _radialGauge.track.start;
     double gaugeEnd = _radialGauge.track.end;
 
-    // final center = Offset(offset.dx, offset.dy);
+    double containerWidth = constraints.maxWidth;
+    double containerHeight = constraints.maxHeight;
+    double containerShortestSide = min(containerWidth, containerHeight);
+    final childSize = child?.computeDryLayout(constraints);
+    final childOffsetX = (childSize?.width ?? 0.0) / 2;
+    final childOffsetY = (childSize?.height ?? 0.0) / 2;
+
     final center = Offset(
-        1440 * _radialGauge.xCenterCoordinate -
-            2 * _radialGauge.track.thickness,
-        900 * _radialGauge.yCenterCoordinate - _radialGauge.track.thickness);
+        containerWidth * _radialGauge.xCenterCoordinate + offset.dx,
+        containerHeight * _radialGauge.yCenterCoordinate + offset.dy);
+
     double value = calculateValueAngle(_value, gaugeStart, gaugeEnd);
     double startAngle = (_radialGauge.track.startAngle - 180) * (pi / 180);
     double endAngle = (_radialGauge.track.endAngle - 180) * (pi / 180);
 
     final double angle = startAngle + (value / 100) * (endAngle - startAngle);
 
     double circlePointerOffset =
-        (900 / 2 - _radialGauge.track.thickness) * _radialGauge.radiusFactor;
+        (containerShortestSide / 2 - _radialGauge.track.thickness) *
+            _radialGauge.radiusFactor;
+
+    double circlePointerEndX =
+        center.dx + circlePointerOffset * cos(angle) - childOffsetX;
+    double circlePointerEndY =
+        center.dy + circlePointerOffset * sin(angle) - childOffsetY;
 
-    double circlePointerEndX = center.dx + circlePointerOffset * cos(angle);
-    double circlePointerEndY = center.dy + circlePointerOffset * sin(angle);
-    // canvas.drawCircle(Offset(circlePointerEndX, circlePointerEndY), 30,
-    //     Paint()..color = Colors.red);
     super.paint(context, Offset(circlePointerEndX, circlePointerEndY));
   }