Added support to enlarge center option and keep fixed size for others

lib/carousel_options.dart

@@ -135,35 +135,38 @@ class CarouselOptions {
 
   final Color? overlayColor;
 
-  CarouselOptions({
-    this.height,
-    this.aspectRatio = 16 / 9,
-    this.viewportFraction = 0.8,
-    this.initialPage = 0,
-    this.enableInfiniteScroll = true,
-    this.animateToClosest = true,
-    this.reverse = false,
-    this.autoPlay = false,
-    this.autoPlayInterval = const Duration(seconds: 4),
-    this.autoPlayAnimationDuration = const Duration(milliseconds: 800),
-    this.autoPlayCurve = Curves.fastOutSlowIn,
-    this.enlargeCenterPage = false,
-    this.onPageChanged,
-    this.onScrolled,
-    this.scrollPhysics,
-    this.pageSnapping = true,
-    this.scrollDirection = Axis.horizontal,
-    this.pauseAutoPlayOnTouch = true,
-    this.pauseAutoPlayOnManualNavigate = true,
-    this.pauseAutoPlayInFiniteScroll = false,
-    this.pageViewKey,
-    this.enlargeStrategy = CenterPageEnlargeStrategy.scale,
-    this.enlargeFactor = 0.3,
-    this.disableCenter = false,
-    this.padEnds = true,
-    this.clipBehavior = Clip.hardEdge,
-    this.overlayColor,
-  });
+  //This property defaults to false, if set to true, the center page will be enlarged and the other pages will be fixed.
+  final bool enlargeCenterFixedOthers;
+
+  CarouselOptions(
+      {this.height,
+      this.aspectRatio = 16 / 9,
+      this.viewportFraction = 0.8,
+      this.initialPage = 0,
+      this.enableInfiniteScroll = true,
+      this.animateToClosest = true,
+      this.reverse = false,
+      this.autoPlay = false,
+      this.autoPlayInterval = const Duration(seconds: 4),
+      this.autoPlayAnimationDuration = const Duration(milliseconds: 800),
+      this.autoPlayCurve = Curves.fastOutSlowIn,
+      this.enlargeCenterPage = false,
+      this.onPageChanged,
+      this.onScrolled,
+      this.scrollPhysics,
+      this.pageSnapping = true,
+      this.scrollDirection = Axis.horizontal,
+      this.pauseAutoPlayOnTouch = true,
+      this.pauseAutoPlayOnManualNavigate = true,
+      this.pauseAutoPlayInFiniteScroll = false,
+      this.pageViewKey,
+      this.enlargeStrategy = CenterPageEnlargeStrategy.scale,
+      this.enlargeFactor = 0.3,
+      this.disableCenter = false,
+      this.padEnds = true,
+      this.clipBehavior = Clip.hardEdge,
+      this.overlayColor,
+      this.enlargeCenterFixedOthers = false});
 
   ///Generate new [CarouselOptions] based on old ones.
 
@@ -193,7 +196,8 @@ class CarouselOptions {
           bool? disableCenter,
           Clip? clipBehavior,
           bool? padEnds,
-          Color? overlayColor}) =>
+          Color? overlayColor,
+          bool? enlargeCenterFixedOthers}) =>
       CarouselOptions(
         height: height ?? this.height,
         aspectRatio: aspectRatio ?? this.aspectRatio,
@@ -221,5 +225,6 @@ class CarouselOptions {
         clipBehavior: clipBehavior ?? this.clipBehavior,
         padEnds: padEnds ?? this.padEnds,
         overlayColor: overlayColor ?? this.overlayColor,
+        enlargeCenterFixedOthers: enlargeCenterFixedOthers ?? this.enlargeCenterFixedOthers,
       );
 }

lib/carousel_slider.dart

@@ -360,7 +360,8 @@ class CarouselSliderState extends State<CarouselSlider> with TickerProviderState
               }
 
               final double enlargeFactor = options.enlargeFactor.clamp(0.0, 1.0);
-              final num distortionRatio = (1 - (itemOffset.abs() * enlargeFactor)).clamp(0.0, 1.0);
+              final offsetValue = options.enlargeCenterFixedOthers ? itemOffset.abs().clamp(0, 1) : itemOffset.abs();
+              final num distortionRatio = (1 - (offsetValue * enlargeFactor)).clamp(0.0, 1.0);
               distortionValue = Curves.easeOut.transform(distortionRatio as double);
               opacityValue = 1 - distortionRatio;
             }