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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:ui' show Canvas, Clip, Paint, Path, RRect, Rect, VoidCallback;
/// Clip utilities used by [PaintingContext].
abstract class ClipContext {
/// The canvas on which to paint.
Canvas get canvas;
void _clipAndPaint(void Function(bool doAntiAlias) canvasClipCall, Clip clipBehavior, Rect bounds, VoidCallback painter) {
assert(canvasClipCall != null);
canvas.save();
switch (clipBehavior) {
case Clip.none:
break;
case Clip.hardEdge:
canvasClipCall(false);
break;
case Clip.antiAlias:
canvasClipCall(true);
break;
case Clip.antiAliasWithSaveLayer:
canvasClipCall(true);
canvas.saveLayer(bounds, Paint());
break;
}
painter();
if (clipBehavior == Clip.antiAliasWithSaveLayer) {
canvas.restore();
}
canvas.restore();
}
/// Clip [canvas] with [Path] according to [Clip] and then paint. [canvas] is
/// restored to the pre-clip status afterwards.
///
/// `bounds` is the saveLayer bounds used for [Clip.antiAliasWithSaveLayer].
void clipPathAndPaint(Path path, Clip clipBehavior, Rect bounds, VoidCallback painter) {
_clipAndPaint((bool doAntiAlias) => canvas.clipPath(path, doAntiAlias: doAntiAlias), clipBehavior, bounds, painter);
}
/// Clip [canvas] with [Path] according to `rrect` and then paint. [canvas] is
/// restored to the pre-clip status afterwards.
///
/// `bounds` is the saveLayer bounds used for [Clip.antiAliasWithSaveLayer].
void clipRRectAndPaint(RRect rrect, Clip clipBehavior, Rect bounds, VoidCallback painter) {
_clipAndPaint((bool doAntiAlias) => canvas.clipRRect(rrect, doAntiAlias: doAntiAlias), clipBehavior, bounds, painter);
}
/// Clip [canvas] with [Path] according to `rect` and then paint. [canvas] is
/// restored to the pre-clip status afterwards.
///
/// `bounds` is the saveLayer bounds used for [Clip.antiAliasWithSaveLayer].
void clipRectAndPaint(Rect rect, Clip clipBehavior, Rect bounds, VoidCallback painter) {
_clipAndPaint((bool doAntiAlias) => canvas.clipRect(rect, doAntiAlias: doAntiAlias), clipBehavior, bounds, painter);
}
}