FlutterClippingMaskView Class Reference

#include <FlutterPlatformViews_Internal.h>

Inheritance diagram for FlutterClippingMaskView:

Instance Methods
(instancetype)	- initWithFrame:screenScale:
(void)	- reset
(void)	- clipRect:matrix:
(void)	- clipRRect:matrix:
(void)	- clipPath:matrix:
(instancetype)	- initWithFrame: [implementation]
(BOOL)	- pointInside:withEvent: [implementation]
(void)	- drawRect: [implementation]
(fml::CFRef< CGPathRef >)	- getTransformedPath:matrix: [implementation]

Properties
CATransform3D	reverseScreenScale [implementation]

Detailed Description

Definition at line 31 of file FlutterPlatformViews_Internal.h.

Method Documentation

clipPath:matrix:

- (void) clipPath:		(const SkPath&)	path
matrix:		(const SkMatrix&)	matrix

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                :(const SkPath&)path matrix:(const SkMatrix&)matrix {
  if (!path.isValid()) {
    return;
  }
  if (path.isEmpty()) {
    return;
  }
  CGMutablePathRef pathRef = CGPathCreateMutable();
 
  // Loop through all verbs and translate them into CGPath
  SkPath::Iter iter(path, true);
  SkPoint pts[kMaxPointsInVerb];
  SkPath::Verb verb = iter.next(pts);
  SkPoint last_pt_from_last_verb = SkPoint::Make(0, 0);
  while (verb != SkPath::kDone_Verb) {
    if (verb == SkPath::kLine_Verb || verb == SkPath::kQuad_Verb || verb == SkPath::kConic_Verb ||
        verb == SkPath::kCubic_Verb) {
      FML_DCHECK(last_pt_from_last_verb == pts[0]);
    }
    switch (verb) {
      case SkPath::kMove_Verb: {
        CGPathMoveToPoint(pathRef, nil, pts[0].x(), pts[0].y());
        last_pt_from_last_verb = pts[0];
        break;
      }
      case SkPath::kLine_Verb: {
        CGPathAddLineToPoint(pathRef, nil, pts[1].x(), pts[1].y());
        last_pt_from_last_verb = pts[1];
        break;
      }
      case SkPath::kQuad_Verb: {
        CGPathAddQuadCurveToPoint(pathRef, nil, pts[1].x(), pts[1].y(), pts[2].x(), pts[2].y());
        last_pt_from_last_verb = pts[2];
        break;
      }
      case SkPath::kConic_Verb: {
        // Conic is not available in quartz, we use quad to approximate.
        // TODO(cyanglaz): Better approximate the conic path.
        // https://github.com/flutter/flutter/issues/35062
        CGPathAddQuadCurveToPoint(pathRef, nil, pts[1].x(), pts[1].y(), pts[2].x(), pts[2].y());
        last_pt_from_last_verb = pts[2];
        break;
      }
      case SkPath::kCubic_Verb: {
        CGPathAddCurveToPoint(pathRef, nil, pts[1].x(), pts[1].y(), pts[2].x(), pts[2].y(),
                              pts[3].x(), pts[3].y());
        last_pt_from_last_verb = pts[3];
        break;
      }
      case SkPath::kClose_Verb: {
        CGPathCloseSubpath(pathRef);
        break;
      }
      case SkPath::kDone_Verb: {
        break;
      }
    }
    verb = iter.next(pts);
  }
  // The `matrix` is based on the physical pixels, convert it to UIKit points.
  CATransform3D matrixInPoints =
      CATransform3DConcat(flutter::GetCATransform3DFromSkMatrix(matrix), _reverseScreenScale);
  paths_.push_back([self getTransformedPath:pathRef matrix:matrixInPoints]);
}

clipRect:matrix:

- (void) clipRect:		(const SkRect&)	clipSkRect
matrix:		(const SkMatrix&)	matrix

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                :(const SkRect&)clipSkRect matrix:(const SkMatrix&)matrix {
  CGRect clipRect = flutter::GetCGRectFromSkRect(clipSkRect);
  CGPathRef path = CGPathCreateWithRect(clipRect, nil);
  // The `matrix` is based on the physical pixels, convert it to UIKit points.
  CATransform3D matrixInPoints =
      CATransform3DConcat(flutter::GetCATransform3DFromSkMatrix(matrix), _reverseScreenScale);
  paths_.push_back([self getTransformedPath:path matrix:matrixInPoints]);
}

clipRRect:matrix:

- (void) clipRRect:		(const SkRRect&)	clipSkRRect
matrix:		(const SkMatrix&)	matrix

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                 :(const SkRRect&)clipSkRRect matrix:(const SkMatrix&)matrix {
  CGPathRef pathRef = nullptr;
  switch (clipSkRRect.getType()) {
    case SkRRect::kEmpty_Type: {
      break;
    }
    case SkRRect::kRect_Type: {
      [self clipRect:clipSkRRect.rect() matrix:matrix];
      return;
    }
    case SkRRect::kOval_Type:
    case SkRRect::kSimple_Type: {
      CGRect clipRect = flutter::GetCGRectFromSkRect(clipSkRRect.rect());
      pathRef = CGPathCreateWithRoundedRect(clipRect, clipSkRRect.getSimpleRadii().x(),
                                            clipSkRRect.getSimpleRadii().y(), nil);
      break;
    }
    case SkRRect::kNinePatch_Type:
    case SkRRect::kComplex_Type: {
      CGMutablePathRef mutablePathRef = CGPathCreateMutable();
      // Complex types, we manually add each corner.
      SkRect clipSkRect = clipSkRRect.rect();
      SkVector topLeftRadii = clipSkRRect.radii(SkRRect::kUpperLeft_Corner);
      SkVector topRightRadii = clipSkRRect.radii(SkRRect::kUpperRight_Corner);
      SkVector bottomRightRadii = clipSkRRect.radii(SkRRect::kLowerRight_Corner);
      SkVector bottomLeftRadii = clipSkRRect.radii(SkRRect::kLowerLeft_Corner);
 
      // Start drawing RRect
      // Move point to the top left corner adding the top left radii's x.
      CGPathMoveToPoint(mutablePathRef, nil, clipSkRect.fLeft + topLeftRadii.x(), clipSkRect.fTop);
      // Move point horizontally right to the top right corner and add the top right curve.
      CGPathAddLineToPoint(mutablePathRef, nil, clipSkRect.fRight - topRightRadii.x(),
                           clipSkRect.fTop);
      CGPathAddCurveToPoint(mutablePathRef, nil, clipSkRect.fRight, clipSkRect.fTop,
                            clipSkRect.fRight, clipSkRect.fTop + topRightRadii.y(),
                            clipSkRect.fRight, clipSkRect.fTop + topRightRadii.y());
      // Move point vertically down to the bottom right corner and add the bottom right curve.
      CGPathAddLineToPoint(mutablePathRef, nil, clipSkRect.fRight,
                           clipSkRect.fBottom - bottomRightRadii.y());
      CGPathAddCurveToPoint(mutablePathRef, nil, clipSkRect.fRight, clipSkRect.fBottom,
                            clipSkRect.fRight - bottomRightRadii.x(), clipSkRect.fBottom,
                            clipSkRect.fRight - bottomRightRadii.x(), clipSkRect.fBottom);
      // Move point horizontally left to the bottom left corner and add the bottom left curve.
      CGPathAddLineToPoint(mutablePathRef, nil, clipSkRect.fLeft + bottomLeftRadii.x(),
                           clipSkRect.fBottom);
      CGPathAddCurveToPoint(mutablePathRef, nil, clipSkRect.fLeft, clipSkRect.fBottom,
                            clipSkRect.fLeft, clipSkRect.fBottom - bottomLeftRadii.y(),
                            clipSkRect.fLeft, clipSkRect.fBottom - bottomLeftRadii.y());
      // Move point vertically up to the top left corner and add the top left curve.
      CGPathAddLineToPoint(mutablePathRef, nil, clipSkRect.fLeft,
                           clipSkRect.fTop + topLeftRadii.y());
      CGPathAddCurveToPoint(mutablePathRef, nil, clipSkRect.fLeft, clipSkRect.fTop,
                            clipSkRect.fLeft + topLeftRadii.x(), clipSkRect.fTop,
                            clipSkRect.fLeft + topLeftRadii.x(), clipSkRect.fTop);
      CGPathCloseSubpath(mutablePathRef);
 
      pathRef = mutablePathRef;
      break;
    }
  }
  // The `matrix` is based on the physical pixels, convert it to UIKit points.
  CATransform3D matrixInPoints =
      CATransform3DConcat(flutter::GetCATransform3DFromSkMatrix(matrix), _reverseScreenScale);
  // TODO(cyanglaz): iOS does not seem to support hard edge on CAShapeLayer. It clearly stated that
  // the CAShaperLayer will be drawn antialiased. Need to figure out a way to do the hard edge
  // clipping on iOS.
  paths_.push_back([self getTransformedPath:pathRef matrix:matrixInPoints]);
}

drawRect:

- (void) drawRect: (CGRect)  rect

implementation

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                :(CGRect)rect {
  CGContextRef context = UIGraphicsGetCurrentContext();
  CGContextSaveGState(context);
 
  // For mask view, only the alpha channel is used.
  CGContextSetAlpha(context, 1);
 
  for (size_t i = 0; i < paths_.size(); i++) {
    CGContextAddPath(context, paths_.at(i));
    CGContextClip(context);
  }
  CGContextFillRect(context, rect);
  CGContextRestoreGState(context);
}

getTransformedPath:matrix:

- (CFRef< CGPathRef >) FlutterClippingMaskView: (CGPathRef)  path matrix: (CATransform3D)  matrix

implementation

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                                         :(CGPathRef)path matrix:(CATransform3D)matrix {
  CGAffineTransform affine =
      CGAffineTransformMake(matrix.m11, matrix.m12, matrix.m21, matrix.m22, matrix.m41, matrix.m42);
  CGPathRef transformedPath = CGPathCreateCopyByTransformingPath(path, &affine);
  CGPathRelease(path);
  return fml::CFRef<CGPathRef>(transformedPath);
}

initWithFrame:

- (instancetype) initWithFrame: (CGRect)  frame

implementation

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                             :(CGRect)frame {
  return [self initWithFrame:frame screenScale:[UIScreen mainScreen].scale];
}

initWithFrame:screenScale:

- (instancetype) initWithFrame:		(CGRect)	frame
screenScale:		(CGFloat)	screenScale

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                             :(CGRect)frame screenScale:(CGFloat)screenScale {
  if (self = [super initWithFrame:frame]) {
    self.backgroundColor = UIColor.clearColor;
    _reverseScreenScale = CATransform3DMakeScale(1 / screenScale, 1 / screenScale, 1);
  }
  return self;
}

pointInside:withEvent:

- (BOOL) pointInside: (CGPoint)  point withEvent: (UIEvent*)  event

implementation

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

                   :(CGPoint)point withEvent:(UIEvent*)event {
  return NO;
}

reset

- (void) reset

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

              {
  paths_.clear();
  [self setNeedsDisplay];
}

Property Documentation

reverseScreenScale

- (CATransform3D) reverseScreenScale

readwritenonatomicassignimplementation

Provided by category FlutterClippingMaskView().

Definition at line 256 of file FlutterPlatformViews_Internal.mm.

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The documentation for this class was generated from the following files:

• shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h
• shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.mm