feat: impl getSuperRoundedRectPath

siui/core/painter.py

@@ -1,12 +1,15 @@
 from __future__ import annotations
 
+import math
+from functools import lru_cache
 from typing import TYPE_CHECKING, Optional
 
-from PyQt5.QtCore import Qt
-from PyQt5.QtGui import QPainter
+from PyQt5.QtCore import QPointF, QRectF, Qt
+from PyQt5.QtGui import QPainter, QPainterPath
 
 if TYPE_CHECKING:
     from PyQt5.QtGui import QFont, QPaintDevice
+
     from siui.typing import T_Brush, T_PenStyle, T_RenderHint
 
 
@@ -15,7 +18,7 @@ def createPainter(
     renderHint: T_RenderHint = QPainter.RenderHint.Antialiasing,
     penStyle: T_PenStyle = Qt.PenStyle.NoPen,
     brush: T_Brush = None,
-    font: Optional[QFont] = None,
+    font: QFont | None = None,
 ) -> QPainter:
     """构造并初始化 QPainter 对象
     应该使用 with 关键字来创建和关闭 QPainter 对象
@@ -44,3 +47,96 @@ def createPainter(
         painter.setFont(font)
 
     return painter
+
+
+def _superSin(x: float, power: float = 5.0) -> float:
+    return math.copysign(abs(math.sin(x)) ** (2 / power), math.sin(x))
+
+
+def _superCos(x: float, power: float = 5.0) -> float:
+    return math.copysign(abs(math.cos(x)) ** (2 / power), math.cos(x))
+
+
+@lru_cache(maxsize=None)
+def _getSuperRoundedPoints(radius_x: float, radius_y: float, power: float, quality: int):
+    points = []
+    for i in range(quality + 1):
+        points.append(QPointF((_superSin(2 * math.pi * i / quality, power) + 0) * radius_x,
+                              (_superCos(2 * math.pi * i / quality, power) + 0) * radius_y))
+    return points
+
+
+@lru_cache(maxsize=None)
+def _cachedGetSuperRoundedRectPath(rect_tuple: tuple,
+                                   radius_x: float,
+                                   radius_y: float,
+                                   power: float,
+                                   quality: int) -> QPainterPath:
+    rect = QRectF(*rect_tuple)
+    path = QPainterPath()
+
+    if quality == -1:
+        quality = max(radius_x, radius_y) // 4 * 4
+
+    points = _getSuperRoundedPoints(radius_x, radius_y, power, quality)
+    inner_rect = QRectF(rect.x() + radius_x, rect.y() + radius_y,
+                        rect.width() - 2 * radius_x, rect.height() - 2 * radius_y)
+
+    q = quality
+
+    path.moveTo(points[q // 4 * 0] + inner_rect.bottomRight())
+    delta = inner_rect.bottomRight()
+    for i in range(q // 4 * 0, q // 4 * 1 + 1):
+        mid_point = (points[i] + points[i + 1]) / 2 + delta
+        point = points[i] + delta
+        path.quadTo(point, mid_point)
+
+    delta = inner_rect.topRight()
+    for i in range(q // 4 * 1, q // 4 * 2 + 1):
+        mid_point = (points[i] + points[i + 1]) / 2 + delta
+        point = points[i] + delta
+        path.quadTo(point, mid_point)
+
+    delta = inner_rect.topLeft()
+    for i in range(q // 4 * 2, q // 4 * 3 + 1):
+        mid_point = (points[i] + points[i + 1]) / 2 + delta
+        point = points[i] + delta
+        path.quadTo(point, mid_point)
+
+    delta = inner_rect.bottomLeft()
+    for i in range(q // 4 * 3, q // 4 * 4):
+        mid_point = (points[i] + points[i + 1]) / 2 + delta
+        point = points[i] + delta
+        path.quadTo(point, mid_point)
+
+    path.lineTo(points[-1] + inner_rect.bottomLeft())  # 连接到最后一个点
+
+    return path
+
+
+def getSuperRoundedRectPath(rect: QRectF,
+                            radius_x: float,
+                            radius_y: float,
+                            power: float = 5.0,
+                            quality: int = -1) -> QPainterPath:
+    """生成并返回一个超椭圆圆角矩形的路径
+
+    参数:
+        - radius_x: float 圆角的横轴半径
+        - radius_y: float 圆角的纵轴半径
+        - power: float 超椭圆方程的幂数
+        - quality: int 采样品质，若传入 -1，则根据圆角半径自动选择品质，其他传入值应为 4 的整数倍
+
+    返回:
+        QPainterPath 对象实例
+
+    该函数启用了缓存，密集绘制友好
+    """
+
+    rect_tuple = (rect.x(), rect.y(), rect.width(), rect.height())
+    return _cachedGetSuperRoundedRectPath(rect_tuple, radius_x, radius_y, power, quality)
+
+
+__all__ = [
+    "createPainter", "getSuperRoundedRectPath"
+]