library: Replace smooth rounded corners

* from https://github.com/Kyant0/Capsule

Author: YuKongA

docs/guide/utils.md

@@ -203,32 +203,76 @@ The `PressFeedbackType` enum defines different types of visual feedback that can
 | Sink | Applies a sink effect, where the component scales down slightly when pressed          |
 | Tilt | Applies a tilt effect, where the component tilts slightly based on the touch position |
 
-## Smooth Rounded Corners (SmoothRoundedCornerShape)
+## Smooth Rounded Corners (G2RoundedCornerShape)
 
-`SmoothRoundedCornerShape` provides smoother rounded corners compared to the standard `RoundedCornerShape`.
+`G2RoundedCornerShape` provides visually smoother corners than the standard `RoundedCornerShape` by blending part of the circular arc with Bézier transitions. It supports: a single uniform corner size, per-corner sizes (Dp / px / percent), preset or custom smoothness via `CornerSmoothness`, and a ready-made `CapsuleShape()` helper.
+
+> Source: https://github.com/Kyant0/Capsule (Apache-2.0 License).
+
+### API Overview
+
+Key entry points (overloads):
+
+```kotlin
+G2RoundedCornerShape(size: Dp, cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+G2RoundedCornerShape(
+    topStart: Dp = 0.dp,
+    topEnd: Dp = 0.dp,
+    bottomEnd: Dp = 0.dp,
+    bottomStart: Dp = 0.dp,
+    cornerSmoothness: CornerSmoothness = CornerSmoothness.Default
+)
+G2RoundedCornerShape(percent: Int, cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+CapsuleShape(cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+```
+
+`CornerSmoothness` parameters:
+* `circleFraction`: 0f..1f portion of a quarter circle preserved (1f = normal rounded corner, no smoothing blend)
+* `extendedFraction`: how much the control points extend horizontally/vertically to create a softer capsule-like shape
+
+Presets:
+* `CornerSmoothness.Default` – balanced smoothness (softened corners)
+* `CornerSmoothness.None` – equivalent to a regular rounded corner (no extra smoothing)
 
 ### Basic Usage
 
 ```kotlin
-Surface(
-    shape = SmoothRoundedCornerShape(16.dp)
-) {
-    // Content
+Surface(shape = G2RoundedCornerShape(16.dp)) {
+    /* 内容 */
 }
 ```
 
-### Custom Smoothness and Different Angles
+### Per-Corner Sizes
 
 ```kotlin
 Surface(
-    shape = SmoothRoundedCornerShape(
-        smoothing = 0.8f, // Smoothness, higher values are smoother
+    shape = G2RoundedCornerShape(
         topStart = 16.dp,
         topEnd = 16.dp,
         bottomStart = 8.dp,
-        bottomEnd = 8.dp
+        bottomEnd = 8.dp,
+        cornerSmoothness = CornerSmoothness.Default
     )
-) {
+) { /* Content */ }
+```
+
+### Capsule Shape
+
+```kotlin
+Surface(shape = CapsuleShape()) { /* Content */ }
+```
+
+### Custom Smoothness
+
+You can craft your own smoothness (smaller `circleFraction` & higher `extendedFraction` => softer / more elongated transition):
+
+```kotlin
+val ExtraSmooth = CornerSmoothness(
+    circleFraction = 0.55f,   // retain 55% of the arc; lower -> more smoothing
+    extendedFraction = 0.90f  // push Bézier handles further for a pill-like feel
+)
+
+Surface(shape = G2RoundedCornerShape(24.dp, cornerSmoothness = ExtraSmooth)) {
     // Content
 }
 ```

docs/zh_CN/guide/utils.md

@@ -203,32 +203,76 @@ Box(
 | Sink | 应用下沉效果，组件在按下时轻微缩小     |
 | Tilt | 应用倾斜效果，组件根据触摸位置轻微倾斜 |
 
-## 平滑圆角 (SmoothRoundedCornerShape)
+## 平滑圆角 (G2RoundedCornerShape)
 
-`SmoothRoundedCornerShape` 提供了比标准 `RoundedCornerShape` 更加平滑的圆角效果。
+`G2RoundedCornerShape` 通过在标准圆角圆弧与 Bézier 过渡之间混合，实现比 `RoundedCornerShape` 更柔和、视觉更自然的圆角。它支持：统一圆角值、分别设置四个角（支持 Dp / px / 百分比）、通过 `CornerSmoothness` 预设或自定义平滑度，以及快捷的 `CapsuleShape()` 胶囊形状。
+
+> 来源: https://github.com/Kyant0/Capsule (Apache-2.0 License)。
+
+### 核心 API
+
+常用构造函数（重载）：
+
+```kotlin
+G2RoundedCornerShape(size: Dp, cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+G2RoundedCornerShape(
+    topStart: Dp = 0.dp,
+    topEnd: Dp = 0.dp,
+    bottomEnd: Dp = 0.dp,
+    bottomStart: Dp = 0.dp,
+    cornerSmoothness: CornerSmoothness = CornerSmoothness.Default
+)
+G2RoundedCornerShape(percent: Int, cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+CapsuleShape(cornerSmoothness: CornerSmoothness = CornerSmoothness.Default)
+```
+
+`CornerSmoothness` 参数说明：
+* `circleFraction`: 0f..1f，表示保留四分之一圆弧的比例（1f = 传统圆角，不做平滑混合）
+* `extendedFraction`: 控制 Bézier 控制点向外延伸的程度，越大越接近椭圆/胶囊视觉
+
+预设：
+* `CornerSmoothness.Default` – 默认柔滑（推荐常规使用）
+* `CornerSmoothness.None` – 与普通圆角等效（无额外平滑）
 
 ### 基本使用
 
 ```kotlin
-Surface(
-    shape = SmoothRoundedCornerShape(16.dp)
-) {
-    // 内容
+Surface(shape = G2RoundedCornerShape(16.dp)) {
+    /* 内容 */
 }
 ```
 
-### 自定义平滑程度和不同角度
+### 分别指定四个角
 
 ```kotlin
 Surface(
-    shape = SmoothRoundedCornerShape(
-        smoothing = 0.8f, // 平滑度，值越高越平滑
+    shape = G2RoundedCornerShape(
         topStart = 16.dp,
         topEnd = 16.dp,
         bottomStart = 8.dp,
-        bottomEnd = 8.dp
+        bottomEnd = 8.dp,
+        cornerSmoothness = CornerSmoothness.Default
     )
-) {
+) { /* 内容 */ }
+```
+
+### 胶囊形状
+
+```kotlin
+Surface(shape = CapsuleShape()) { /* 内容 */ }
+```
+
+### 自定义平滑度
+
+（降低 `circleFraction` + 提高 `extendedFraction` => 更软、更延展）
+
+```kotlin
+val ExtraSmooth = CornerSmoothness(
+    circleFraction = 0.55f,   // 保留 55% 圆弧，越低越“圆润”
+    extendedFraction = 0.90f  // 控制点更外扩，接近胶囊
+)
+
+Surface(shape = G2RoundedCornerShape(24.dp, cornerSmoothness = ExtraSmooth)) {
     // 内容
 }
 ```

iosApp/iosApp/Info.plist

@@ -17,7 +17,7 @@
 	<key>CFBundleShortVersionString</key>
 	<string>1.0.4</string>
 	<key>CFBundleVersion</key>
-	<string>511</string>
+	<string>512</string>
 	<key>LSRequiresIPhoneOS</key>
 	<true/>
 	<key>CADisableMinimumFrameDurationOnPhone</key>

miuix/src/commonMain/kotlin/top/yukonga/miuix/kmp/basic/Button.kt

@@ -11,9 +11,7 @@ import androidx.compose.foundation.layout.defaultMinSize
 import androidx.compose.foundation.layout.padding
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.Immutable
-import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
@@ -23,7 +21,7 @@ import androidx.compose.ui.semantics.semantics
 import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import top.yukonga.miuix.kmp.theme.MiuixTheme
-import top.yukonga.miuix.kmp.utils.SmoothRoundedCornerShape
+import top.yukonga.miuix.kmp.utils.G2RoundedCornerShape
 
 /**
  * A [Button] component with Miuix style.
@@ -50,7 +48,7 @@ fun Button(
     insideMargin: PaddingValues = ButtonDefaults.InsideMargin,
     content: @Composable RowScope.() -> Unit
 ) {
-    val shape = remember(cornerRadius) { SmoothRoundedCornerShape(cornerRadius) }
+    val shape = remember(cornerRadius) { G2RoundedCornerShape(cornerRadius) }
     val color = if (enabled) colors.color else colors.disabledColor
     Surface(
         onClick = onClick,
@@ -95,7 +93,7 @@ fun TextButton(
     minHeight: Dp = ButtonDefaults.MinHeight,
     insideMargin: PaddingValues = ButtonDefaults.InsideMargin
 ) {
-    val shape = remember(cornerRadius) { SmoothRoundedCornerShape(cornerRadius) }
+    val shape = remember(cornerRadius) { G2RoundedCornerShape(cornerRadius) }
     val color = if (enabled) colors.color else colors.disabledColor
     val textColor = if (enabled) colors.textColor else colors.disabledTextColor
     Surface(

miuix/src/commonMain/kotlin/top/yukonga/miuix/kmp/basic/Card.kt

@@ -18,13 +18,10 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.Immutable
-import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
@@ -36,8 +33,9 @@ import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import top.yukonga.miuix.kmp.theme.LocalContentColor
 import top.yukonga.miuix.kmp.theme.MiuixTheme
+import top.yukonga.miuix.kmp.utils.CornerSmoothness
+import top.yukonga.miuix.kmp.utils.G2RoundedCornerShape
 import top.yukonga.miuix.kmp.utils.PressFeedbackType
-import top.yukonga.miuix.kmp.utils.SmoothRoundedCornerShape
 import top.yukonga.miuix.kmp.utils.pressSink
 import top.yukonga.miuix.kmp.utils.pressTilt
 
@@ -165,8 +163,8 @@ private fun BasicCard(
     cornerRadius: Dp = CardDefaults.CornerRadius,
     content: @Composable () -> Unit,
 ) {
-    val shape = remember(cornerRadius) { SmoothRoundedCornerShape(cornerRadius) }
-    val clipShape = remember(cornerRadius) { RoundedCornerShape(cornerRadius) }
+    val shape = remember(cornerRadius) { G2RoundedCornerShape(cornerRadius) }
+    val clipShape = remember(cornerRadius) { G2RoundedCornerShape(cornerRadius, CornerSmoothness.None) }
 
     CompositionLocalProvider(
         LocalContentColor provides colors.contentColor,
@@ -176,8 +174,8 @@ private fun BasicCard(
                 .semantics(mergeDescendants = false) {
                     isTraversalGroup = true
                 }
-                .background(color = colors.color, shape = shape)
-                .clip(clipShape), // For touch feedback, there is a problem when using SmoothRoundedCornerShape.
+                .clip(clipShape)  // For touch feedback, there is a problem when using G2RoundedCornerShape.
+                .background(color = colors.color, shape = shape),
             propagateMinConstraints = true,
         ) {
             content()

miuix/src/commonMain/kotlin/top/yukonga/miuix/kmp/basic/ColorPalette.kt

@@ -36,7 +36,8 @@ import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.IntSize
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.util.lerp
-import top.yukonga.miuix.kmp.utils.SmoothRoundedCornerShape
+import top.yukonga.miuix.kmp.utils.CapsuleShape
+import top.yukonga.miuix.kmp.utils.G2RoundedCornerShape
 import kotlin.math.abs
 import kotlin.math.max
 import kotlin.math.min
@@ -118,7 +119,7 @@ fun ColorPalette(
                 modifier = Modifier
                     .fillMaxWidth()
                     .height(26.dp)
-                    .clip(SmoothRoundedCornerShape(50.dp))
+                    .clip(CapsuleShape())
                     .background(lastEmittedColor ?: initialColor)
             )
         }
@@ -175,7 +176,7 @@ private fun PaletteCanvas(
     val totalColumns = hueColumns + if (includeGrayColumn) 1 else 0
     val rowSV = remember(rows) { buildRowSV(rows) }
     val grayV = remember(rows) { buildGrayV(rows) }
-    val shape = SmoothRoundedCornerShape(cornerRadius)
+    val shape = G2RoundedCornerShape(cornerRadius)
 
     var sizePx by remember { mutableStateOf(IntSize.Zero) }