| // 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); |
| } |
| } |