From db51537896ed033c5c16a20685e6e740b165bc0e Mon Sep 17 00:00:00 2001
From: Vishesh Handa <me@vhanda.in>
Date: Tue, 23 Feb 2021 10:13:14 +0100
Subject: [PATCH] Remove fork of InteractiveViewer
The fixes are in flutter stable
---
lib/core/interactive_viewer.dart | 1259 ------------------------------
lib/screens/graph_view.dart | 7 +-
2 files changed, 3 insertions(+), 1263 deletions(-)
delete mode 100644 lib/core/interactive_viewer.dart
diff --git a/lib/core/interactive_viewer.dart b/lib/core/interactive_viewer.dart
deleted file mode 100644
index d69d99a5..00000000
--- a/lib/core/interactive_viewer.dart
+++ /dev/null
@@ -1,1259 +0,0 @@
-// 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.
-
-// @dart = 2.8
-
-import 'dart:math' as math;
-
-import 'package:flutter/gestures.dart';
-import 'package:flutter/material.dart';
-import 'package:flutter/physics.dart';
-
-import 'package:vector_math/vector_math_64.dart' show Quad, Vector3, Matrix4;
-
-/// A widget that enables pan and zoom interactions with its child.
-///
-/// The user can transform the child by dragging to pan or pinching to zoom.
-///
-/// By default, InteractiveViewer may draw outside of its original area of the
-/// screen, such as when a child is zoomed in and increases in size. However, it
-/// will not receive gestures outside of its original area. To prevent
-/// InteractiveViewer from drawing outside of its original size, wrap it in a
-/// [ClipRect]. Or, to prevent dead areas where InteractiveViewer does not
-/// receive gestures, be sure that the InteractiveViewer widget is the size of
-/// the area that should be interactive. See
-/// [flutter-go](https://github.com/justinmc/flutter-go) for an example of
-/// robust positioning of an InteractiveViewer child that works for all screen
-/// sizes and child sizes.
-///
-/// The [child] must not be null.
-///
-/// See also:
-/// * The [Flutter Gallery's transformations demo](https://github.com/flutter/gallery/blob/master/lib/demos/reference/transformations_demo.dart),
-/// which includes the use of InteractiveViewer.
-///
-/// {@tool dartpad --template=stateless_widget_scaffold}
-/// This example shows a simple Container that can be panned and zoomed.
-///
-/// ```dart
-/// Widget build(BuildContext context) {
-/// return Center(
-/// child: InteractiveViewer(
-/// boundaryMargin: EdgeInsets.all(20.0),
-/// minScale: 0.1,
-/// maxScale: 1.6,
-/// child: Container(
-/// decoration: BoxDecoration(
-/// gradient: LinearGradient(
-/// begin: Alignment.topCenter,
-/// end: Alignment.bottomCenter,
-/// colors: <Color>[Colors.orange, Colors.red],
-/// stops: <double>[0.0, 1.0],
-/// ),
-/// ),
-/// ),
-/// ),
-/// );
-/// }
-/// ```
-/// {@end-tool}
-@immutable
-class InteractiveViewer extends StatefulWidget {
- /// Create an InteractiveViewer.
- ///
- /// The [child] parameter must not be null.
- InteractiveViewer({
- Key key,
- this.alignPanAxis = false,
- this.boundaryMargin = EdgeInsets.zero,
- this.constrained = true,
- // These default scale values were eyeballed as reasonable limits for common
- // use cases.
- this.maxScale = 2.5,
- this.minScale = 0.8,
- this.onInteractionEnd,
- this.onInteractionStart,
- this.onInteractionUpdate,
- this.panEnabled = true,
- this.scaleEnabled = true,
- this.transformationController,
- @required this.child,
- }) : assert(alignPanAxis != null),
- assert(child != null),
- assert(constrained != null),
- assert(minScale != null),
- assert(minScale > 0),
- assert(minScale.isFinite),
- assert(maxScale != null),
- assert(maxScale > 0),
- assert(!maxScale.isNaN),
- assert(maxScale >= minScale),
- assert(panEnabled != null),
- assert(scaleEnabled != null),
- // boundaryMargin must be either fully infinite or fully finite, but not
- // a mix of both.
- assert((boundaryMargin.horizontal.isInfinite &&
- boundaryMargin.vertical.isInfinite) ||
- (boundaryMargin.top.isFinite &&
- boundaryMargin.right.isFinite &&
- boundaryMargin.bottom.isFinite &&
- boundaryMargin.left.isFinite)),
- super(key: key);
-
- /// If true, panning is only allowed in the direction of the horizontal axis
- /// or the vertical axis.
- ///
- /// In other words, when this is true, diagonal panning is not allowed. A
- /// single gesture begun along one axis cannot also cause panning along the
- /// other axis without stopping and beginning a new gesture. This is a common
- /// pattern in tables where data is displayed in columns and rows.
- final bool alignPanAxis;
-
- /// A margin for the visible boundaries of the child.
- ///
- /// Any transformation that results in the viewport being able to view outside
- /// of the boundaries will be stopped at the boundary. The boundaries do not
- /// rotate with the rest of the scene, so they are always aligned with the
- /// viewport.
- ///
- /// To produce no boundaries at all, pass infinite [EdgeInsets], such as
- /// `EdgeInsets.all(double.infinity)`.
- ///
- /// No edge can be NaN.
- ///
- /// Defaults to [EdgeInsets.zero], which results in boundaries that are the
- /// exact same size and position as the [child].
- final EdgeInsets boundaryMargin;
-
- /// The Widget to perform the transformations on.
- ///
- /// Cannot be null.
- final Widget child;
-
- /// Whether the normal size constraints at this point in the widget tree are
- /// applied to the child.
- ///
- /// If set to false, then the child will be given infinite constraints. This
- /// is often useful when a child should be bigger than the InteractiveViewer.
- ///
- /// Defaults to true.
- ///
- /// {@tool dartpad --template=stateless_widget_scaffold}
- /// This example shows how to create a pannable table. Because the table is
- /// larger than the entire screen, setting `constrained` to false is necessary
- /// to allow it to be drawn to its full size. The parts of the table that
- /// exceed the screen size can then be panned into view.
- ///
- /// ```dart
- /// Widget build(BuildContext context) {
- /// const int _rowCount = 20;
- /// const int _columnCount = 3;
- ///
- /// return Scaffold(
- /// appBar: AppBar(
- /// title: const Text('Pannable Table'),
- /// ),
- /// body: InteractiveViewer(
- /// constrained: false,
- /// scaleEnabled: false,
- /// child: Table(
- /// columnWidths: <int, TableColumnWidth>{
- /// for (int column = 0; column < _columnCount; column += 1)
- /// column: const FixedColumnWidth(300.0),
- /// },
- /// children: <TableRow>[
- /// for (int row = 0; row < _rowCount; row += 1)
- /// TableRow(
- /// children: <Widget>[
- /// for (int column = 0; column < _columnCount; column += 1)
- /// Container(
- /// height: 100,
- /// color: row % 2 + column % 2 == 1 ? Colors.red : Colors.green,
- /// ),
- /// ],
- /// ),
- /// ],
- /// ),
- /// ),
- /// );
- /// }
- /// ```
- /// {@end-tool}
- final bool constrained;
-
- /// If false, the user will be prevented from panning.
- ///
- /// Defaults to true.
- ///
- /// See also:
- ///
- /// * [scaleEnabled], which is similar but for scale.
- final bool panEnabled;
-
- /// If false, the user will be prevented from scaling.
- ///
- /// Defaults to true.
- ///
- /// See also:
- ///
- /// * [panEnabled], which is similar but for panning.
- final bool scaleEnabled;
-
- /// The maximum allowed scale.
- ///
- /// The scale will be clamped between this and [minScale] inclusively.
- ///
- /// Defaults to 2.5.
- ///
- /// Cannot be null, and must be greater than zero and greater than minScale.
- final double maxScale;
-
- /// The minimum allowed scale.
- ///
- /// The scale will be clamped between this and [maxScale] inclusively.
- ///
- /// Defaults to 0.8.
- ///
- /// Cannot be null, and must be a finite number greater than zero and less
- /// than maxScale.
- final double minScale;
-
- /// Called when the user ends a pan or scale gesture on the widget.
- ///
- /// {@template flutter.widgets.interactiveViewer.onInteraction}
- /// Will be called even if the interaction is disabled with
- /// [panEnabled] or [scaleEnabled].
- ///
- /// A [GestureDetector] wrapping the InteractiveViewer will not respond to
- /// [GestureDetector.onScaleStart], [GestureDetector.onScaleUpdate], and
- /// [GestureDetector.onScaleEnd]. Use [onInteractionStart],
- /// [onInteractionUpdate], and [onInteractionEnd] to respond to those
- /// gestures.
- ///
- /// The coordinates returned in the details are viewport coordinates relative
- /// to the parent. See [TransformationController.toScene] for how to
- /// convert the coordinates to scene coordinates relative to the child.
- /// {@endtemplate}
- ///
- /// See also:
- ///
- /// * [onInteractionStart], which handles the start of the same interaction.
- /// * [onInteractionUpdate], which handles an update to the same interaction.
- final GestureScaleEndCallback onInteractionEnd;
-
- /// Called when the user begins a pan or scale gesture on the widget.
- ///
- /// {@macro flutter.widgets.interactiveViewer.onInteraction}
- ///
- /// See also:
- ///
- /// * [onInteractionUpdate], which handles an update to the same interaction.
- /// * [onInteractionEnd], which handles the end of the same interaction.
- final GestureScaleStartCallback onInteractionStart;
-
- /// Called when the user updates a pan or scale gesture on the widget.
- ///
- /// {@macro flutter.widgets.interactiveViewer.onInteraction}
- ///
- /// See also:
- ///
- /// * [onInteractionStart], which handles the start of the same interaction.
- /// * [onInteractionEnd], which handles the end of the same interaction.
- final GestureScaleUpdateCallback onInteractionUpdate;
-
- /// A [TransformationController] for the transformation performed on the
- /// child.
- ///
- /// Whenever the child is transformed, the [Matrix4] value is updated and all
- /// listeners are notified. If the value is set, InteractiveViewer will update
- /// to respect the new value.
- ///
- /// {@tool dartpad --template=stateful_widget_material_ticker}
- /// This example shows how transformationController can be used to animate the
- /// transformation back to its starting position.
- ///
- /// ```dart
- /// final TransformationController _transformationController = TransformationController();
- /// Animation<Matrix4> _animationReset;
- /// AnimationController _controllerReset;
- ///
- /// void _onAnimateReset() {
- /// _transformationController.value = _animationReset.value;
- /// if (!_controllerReset.isAnimating) {
- /// _animationReset?.removeListener(_onAnimateReset);
- /// _animationReset = null;
- /// _controllerReset.reset();
- /// }
- /// }
- ///
- /// void _animateResetInitialize() {
- /// _controllerReset.reset();
- /// _animationReset = Matrix4Tween(
- /// begin: _transformationController.value,
- /// end: Matrix4.identity(),
- /// ).animate(_controllerReset);
- /// _animationReset.addListener(_onAnimateReset);
- /// _controllerReset.forward();
- /// }
- ///
- /// // Stop a running reset to home transform animation.
- /// void _animateResetStop() {
- /// _controllerReset.stop();
- /// _animationReset?.removeListener(_onAnimateReset);
- /// _animationReset = null;
- /// _controllerReset.reset();
- /// }
- ///
- /// void _onInteractionStart(ScaleStartDetails details) {
- /// // If the user tries to cause a transformation while the reset animation is
- /// // running, cancel the reset animation.
- /// if (_controllerReset.status == AnimationStatus.forward) {
- /// _animateResetStop();
- /// }
- /// }
- ///
- /// @override
- /// void initState() {
- /// super.initState();
- /// _controllerReset = AnimationController(
- /// vsync: this,
- /// duration: const Duration(milliseconds: 400),
- /// );
- /// }
- ///
- /// @override
- /// void dispose() {
- /// _controllerReset.dispose();
- /// super.dispose();
- /// }
- ///
- /// @override
- /// Widget build(BuildContext context) {
- /// return Scaffold(
- /// backgroundColor: Theme.of(context).colorScheme.primary,
- /// appBar: AppBar(
- /// automaticallyImplyLeading: false,
- /// title: const Text('Controller demo'),
- /// ),
- /// body: Center(
- /// child: InteractiveViewer(
- /// boundaryMargin: EdgeInsets.all(double.infinity),
- /// transformationController: _transformationController,
- /// minScale: 0.1,
- /// maxScale: 1.0,
- /// onInteractionStart: _onInteractionStart,
- /// child: Container(
- /// decoration: BoxDecoration(
- /// gradient: LinearGradient(
- /// begin: Alignment.topCenter,
- /// end: Alignment.bottomCenter,
- /// colors: <Color>[Colors.orange, Colors.red],
- /// stops: <double>[0.0, 1.0],
- /// ),
- /// ),
- /// ),
- /// ),
- /// ),
- /// persistentFooterButtons: [
- /// IconButton(
- /// onPressed: _animateResetInitialize,
- /// tooltip: 'Reset',
- /// color: Theme.of(context).colorScheme.surface,
- /// icon: const Icon(Icons.replay),
- /// ),
- /// ],
- /// );
- /// }
- /// ```
- /// {@end-tool}
- ///
- /// See also:
- ///
- /// * [ValueNotifier], the parent class of TransformationController.
- /// * [TextEditingController] for an example of another similar pattern.
- final TransformationController transformationController;
-
- /// Returns the closest point to the given point on the given line segment.
- @visibleForTesting
- static Vector3 getNearestPointOnLine(Vector3 point, Vector3 l1, Vector3 l2) {
- final double lengthSquared = math.pow(l2.x - l1.x, 2.0).toDouble() +
- math.pow(l2.y - l1.y, 2.0).toDouble();
-
- // In this case, l1 == l2.
- if (lengthSquared == 0) {
- return l1;
- }
-
- // Calculate how far down the line segment the closest point is and return
- // the point.
- final Vector3 l1P = point - l1;
- final Vector3 l1L2 = l2 - l1;
- final double fraction =
- (l1P.dot(l1L2) / lengthSquared).clamp(0.0, 1.0).toDouble();
- return l1 + l1L2 * fraction;
- }
-
- /// Given a quad, return its axis aligned bounding box.
- @visibleForTesting
- static Quad getAxisAlignedBoundingBox(Quad quad) {
- final double minX = math.min(
- quad.point0.x,
- math.min(
- quad.point1.x,
- math.min(
- quad.point2.x,
- quad.point3.x,
- ),
- ),
- );
- final double minY = math.min(
- quad.point0.y,
- math.min(
- quad.point1.y,
- math.min(
- quad.point2.y,
- quad.point3.y,
- ),
- ),
- );
- final double maxX = math.max(
- quad.point0.x,
- math.max(
- quad.point1.x,
- math.max(
- quad.point2.x,
- quad.point3.x,
- ),
- ),
- );
- final double maxY = math.max(
- quad.point0.y,
- math.max(
- quad.point1.y,
- math.max(
- quad.point2.y,
- quad.point3.y,
- ),
- ),
- );
- return Quad.points(
- Vector3(minX, minY, 0),
- Vector3(maxX, minY, 0),
- Vector3(maxX, maxY, 0),
- Vector3(minX, maxY, 0),
- );
- }
-
- /// Returns true iff the point is inside the rectangle given by the Quad,
- /// inclusively.
- /// Algorithm from https://math.stackexchange.com/a/190373.
- @visibleForTesting
- static bool pointIsInside(Vector3 point, Quad quad) {
- final Vector3 aM = point - quad.point0;
- final Vector3 aB = quad.point1 - quad.point0;
- final Vector3 aD = quad.point3 - quad.point0;
-
- final double aMAB = aM.dot(aB);
- final double aBAB = aB.dot(aB);
- final double aMAD = aM.dot(aD);
- final double aDAD = aD.dot(aD);
-
- return 0 <= aMAB && aMAB <= aBAB && 0 <= aMAD && aMAD <= aDAD;
- }
-
- /// Get the point inside (inclusively) the given Quad that is nearest to the
- /// given Vector3.
- @visibleForTesting
- static Vector3 getNearestPointInside(Vector3 point, Quad quad) {
- // If the point is inside the axis aligned bounding box, then it's ok where
- // it is.
- if (pointIsInside(point, quad)) {
- return point;
- }
-
- // Otherwise, return the nearest point on the quad.
- final List<Vector3> closestPoints = <Vector3>[
- InteractiveViewer.getNearestPointOnLine(point, quad.point0, quad.point1),
- InteractiveViewer.getNearestPointOnLine(point, quad.point1, quad.point2),
- InteractiveViewer.getNearestPointOnLine(point, quad.point2, quad.point3),
- InteractiveViewer.getNearestPointOnLine(point, quad.point3, quad.point0),
- ];
- double minDistance = double.infinity;
- Vector3 closestOverall;
- for (final Vector3 closePoint in closestPoints) {
- final double distance = math.sqrt(
- math.pow(point.x - closePoint.x, 2) +
- math.pow(point.y - closePoint.y, 2),
- );
- if (distance < minDistance) {
- minDistance = distance;
- closestOverall = closePoint;
- }
- }
- return closestOverall;
- }
-
- @override
- _InteractiveViewerState createState() => _InteractiveViewerState();
-}
-
-class _InteractiveViewerState extends State<InteractiveViewer>
- with TickerProviderStateMixin {
- TransformationController _transformationController;
-
- final GlobalKey _childKey = GlobalKey();
- final GlobalKey _parentKey = GlobalKey();
- Animation<Offset> _animation;
- AnimationController _controller;
- Axis _panAxis; // Used with alignPanAxis.
- Offset _referenceFocalPoint; // Point where the current gesture began.
- double _scaleStart; // Scale value at start of scaling gesture.
- double _rotationStart = 0.0; // Rotation at start of rotation gesture.
- double _currentRotation = 0.0; // Rotation of _transformationController.value.
- _GestureType _gestureType;
-
- // TODO(justinmc): Add rotateEnabled parameter to the widget and remove this
- // hardcoded value when the rotation feature is implemented.
- // https://github.com/flutter/flutter/issues/57698
- final bool _rotateEnabled = false;
-
- // Used as the coefficient of friction in the inertial translation animation.
- // This value was eyeballed to give a feel similar to Google Photos.
- static const double _kDrag = 0.0000135;
-
- // The _boundaryRect is calculated by adding the boundaryMargin to the size of
- // the child.
- Rect get _boundaryRect {
- assert(_childKey.currentContext != null);
- assert(!widget.boundaryMargin.left.isNaN);
- assert(!widget.boundaryMargin.right.isNaN);
- assert(!widget.boundaryMargin.top.isNaN);
- assert(!widget.boundaryMargin.bottom.isNaN);
-
- final RenderBox childRenderBox =
- _childKey.currentContext.findRenderObject() as RenderBox;
- final Size childSize = childRenderBox.size;
- final Rect boundaryRect =
- widget.boundaryMargin.inflateRect(Offset.zero & childSize);
- // Boundaries that are partially infinite are not allowed because Matrix4's
- // rotation and translation methods don't handle infinites well.
- assert(
- boundaryRect.isFinite ||
- (boundaryRect.left.isInfinite &&
- boundaryRect.top.isInfinite &&
- boundaryRect.right.isInfinite &&
- boundaryRect.bottom.isInfinite),
- 'boundaryRect must either be infinite in all directions or finite in all directions.');
- return boundaryRect;
- }
-
- // The Rect representing the child's parent.
- Rect get _viewport {
- assert(_parentKey.currentContext != null);
- final RenderBox parentRenderBox =
- _parentKey.currentContext.findRenderObject() as RenderBox;
- return Offset.zero & parentRenderBox.size;
- }
-
- // Return a new matrix representing the given matrix after applying the given
- // translation.
- Matrix4 _matrixTranslate(Matrix4 matrix, Offset translation) {
- if (translation == Offset.zero) {
- return matrix.clone();
- }
-
- final Offset alignedTranslation = widget.alignPanAxis && _panAxis != null
- ? _alignAxis(translation, _panAxis)
- : translation;
-
- final Matrix4 nextMatrix = matrix.clone()
- ..translate(
- alignedTranslation.dx,
- alignedTranslation.dy,
- );
-
- // Transform the viewport to determine where its four corners will be after
- // the child has been transformed.
- final Quad nextViewport = _transformViewport(nextMatrix, _viewport);
-
- // If the boundaries are infinite, then no need to check if the translation
- // fits within them.
- if (_boundaryRect.isInfinite) {
- return nextMatrix;
- }
-
- // Expand the boundaries with rotation. This prevents the problem where a
- // mismatch in orientation between the viewport and boundaries effectively
- // limits translation. With this approach, all points that are visible with
- // no rotation are visible after rotation.
- final Quad boundariesAabbQuad = _getAxisAlignedBoundingBoxWithRotation(
- _boundaryRect,
- _currentRotation,
- );
-
- // If the given translation fits completely within the boundaries, allow it.
- final Offset offendingDistance =
- _exceedsBy(boundariesAabbQuad, nextViewport);
- if (offendingDistance == Offset.zero) {
- return nextMatrix;
- }
-
- // Desired translation goes out of bounds, so translate to the nearest
- // in-bounds point instead.
- final Offset nextTotalTranslation = _getMatrixTranslation(nextMatrix);
- final double currentScale = matrix.getMaxScaleOnAxis();
- final Offset correctedTotalTranslation = Offset(
- nextTotalTranslation.dx - offendingDistance.dx * currentScale,
- nextTotalTranslation.dy - offendingDistance.dy * currentScale,
- );
- // TODO(justinmc): This needs some work to handle rotation properly. The
- // idea is that the boundaries are axis aligned (boundariesAabbQuad), but
- // calculating the translation to put the viewport inside that Quad is more
- // complicated than this when rotated.
- // https://github.com/flutter/flutter/issues/57698
- final Matrix4 correctedMatrix = matrix.clone()
- ..setTranslation(Vector3(
- correctedTotalTranslation.dx,
- correctedTotalTranslation.dy,
- 0.0,
- ));
-
- // Double check that the corrected translation fits.
- final Quad correctedViewport =
- _transformViewport(correctedMatrix, _viewport);
- final Offset offendingCorrectedDistance =
- _exceedsBy(boundariesAabbQuad, correctedViewport);
- if (offendingCorrectedDistance == Offset.zero) {
- return correctedMatrix;
- }
-
- // If the corrected translation doesn't fit in either direction, don't allow
- // any translation at all. This happens when the viewport is larger than the
- // entire boundary.
- if (offendingCorrectedDistance.dx != 0.0 &&
- offendingCorrectedDistance.dy != 0.0) {
- return matrix.clone();
- }
-
- // Otherwise, allow translation in only the direction that fits. This
- // happens when the viewport is larger than the boundary in one direction.
- final Offset unidirectionalCorrectedTotalTranslation = Offset(
- offendingCorrectedDistance.dx == 0.0 ? correctedTotalTranslation.dx : 0.0,
- offendingCorrectedDistance.dy == 0.0 ? correctedTotalTranslation.dy : 0.0,
- );
- return matrix.clone()
- ..setTranslation(Vector3(
- unidirectionalCorrectedTotalTranslation.dx,
- unidirectionalCorrectedTotalTranslation.dy,
- 0.0,
- ));
- }
-
- // Return a new matrix representing the given matrix after applying the given
- // scale.
- Matrix4 _matrixScale(Matrix4 matrix, double scale) {
- if (scale == 1.0) {
- return matrix.clone();
- }
- assert(scale != 0.0);
-
- // Don't allow a scale that results in an overall scale beyond min/max
- // scale.
- final double currentScale =
- _transformationController.value.getMaxScaleOnAxis();
- final double totalScale = currentScale * scale;
- final double clampedTotalScale = totalScale.clamp(
- widget.minScale,
- widget.maxScale,
- ) as double;
- final double clampedScale = clampedTotalScale / currentScale;
- final Matrix4 nextMatrix = matrix.clone()..scale(clampedScale);
-
- // Ensure that the scale cannot make the child so big that it can't fit
- // inside the boundaries (in either direction).
- final double minScale = math.max(
- _viewport.width / _boundaryRect.width,
- _viewport.height / _boundaryRect.height,
- );
- if (clampedTotalScale < minScale) {
- final double minCurrentScale = minScale / currentScale;
- return matrix.clone()..scale(minCurrentScale);
- }
-
- return nextMatrix;
- }
-
- // Return a new matrix representing the given matrix after applying the given
- // rotation.
- Matrix4 _matrixRotate(Matrix4 matrix, double rotation, Offset focalPoint) {
- if (rotation == 0) {
- return matrix.clone();
- }
- final Offset focalPointScene = _transformationController.toScene(
- focalPoint,
- );
- return matrix.clone()
- ..translate(focalPointScene.dx, focalPointScene.dy)
- ..rotateZ(-rotation)
- ..translate(-focalPointScene.dx, -focalPointScene.dy);
- }
-
- // Returns true iff the given _GestureType is enabled.
- bool _gestureIsSupported(_GestureType gestureType) {
- switch (gestureType) {
- case _GestureType.rotate:
- return _rotateEnabled;
-
- case _GestureType.scale:
- return widget.scaleEnabled;
-
- case _GestureType.pan:
- default:
- return widget.panEnabled;
- }
- }
-
- // Decide which type of gesture this is by comparing the amount of scale
- // and rotation in the gesture, if any. Scale starts at 1 and rotation
- // starts at 0. Pan will have no scale and no rotation because it uses only one
- // finger.
- _GestureType _getGestureType(ScaleUpdateDetails details) {
- final double scale = !widget.scaleEnabled ? 1.0 : details.scale;
- final double rotation = !_rotateEnabled ? 0.0 : details.rotation;
- if ((scale - 1).abs() > rotation.abs()) {
- return _GestureType.scale;
- } else if (rotation != 0.0) {
- return _GestureType.rotate;
- } else {
- return _GestureType.pan;
- }
- }
-
- // Handle the start of a gesture. All of pan, scale, and rotate are handled
- // with GestureDetector's scale gesture.
- void _onScaleStart(ScaleStartDetails details) {
- if (widget.onInteractionStart != null) {
- widget.onInteractionStart(details);
- }
-
- if (_controller.isAnimating) {
- _controller.stop();
- _controller.reset();
- _animation?.removeListener(_onAnimate);
- _animation = null;
- }
-
- _gestureType = null;
- _panAxis = null;
- _scaleStart = _transformationController.value.getMaxScaleOnAxis();
- _referenceFocalPoint = _transformationController.toScene(
- details.localFocalPoint,
- );
- _rotationStart = _currentRotation;
- }
-
- // Handle an update to an ongoing gesture. All of pan, scale, and rotate are
- // handled with GestureDetector's scale gesture.
- void _onScaleUpdate(ScaleUpdateDetails details) {
- final double scale = _transformationController.value.getMaxScaleOnAxis();
- if (widget.onInteractionUpdate != null) {
- widget.onInteractionUpdate(ScaleUpdateDetails(
- focalPoint: _transformationController.toScene(
- details.localFocalPoint,
- ),
- scale: details.scale,
- rotation: details.rotation,
- ));
- }
- final Offset focalPointScene = _transformationController.toScene(
- details.localFocalPoint,
- );
-
- if (_gestureType == _GestureType.pan) {
- // When a gesture first starts, it sometimes has no change in scale and
- // rotation despite being a two-finger gesture. Here the gesture is
- // allowed to be reinterpreted as its correct type after originally
- // being marked as a pan.
- _gestureType = _getGestureType(details);
- } else {
- _gestureType ??= _getGestureType(details);
- }
- if (!_gestureIsSupported(_gestureType)) {
- return;
- }
-
- switch (_gestureType) {
- case _GestureType.scale:
- assert(_scaleStart != null);
- // details.scale gives us the amount to change the scale as of the
- // start of this gesture, so calculate the amount to scale as of the
- // previous call to _onScaleUpdate.
- final double desiredScale = _scaleStart * details.scale;
- final double scaleChange = desiredScale / scale;
- _transformationController.value = _matrixScale(
- _transformationController.value,
- scaleChange,
- );
-
- // While scaling, translate such that the user's two fingers stay on
- // the same places in the scene. That means that the focal point of
- // the scale should be on the same place in the scene before and after
- // the scale.
- final Offset focalPointSceneScaled = _transformationController.toScene(
- details.localFocalPoint,
- );
- _transformationController.value = _matrixTranslate(
- _transformationController.value,
- focalPointSceneScaled - _referenceFocalPoint,
- );
-
- // details.localFocalPoint should now be at the same location as the
- // original _referenceFocalPoint point. If it's not, that's because
- // the translate came in contact with a boundary. In that case, update
- // _referenceFocalPoint so subsequent updates happen in relation to
- // the new effective focal point.
- final Offset focalPointSceneCheck = _transformationController.toScene(
- details.localFocalPoint,
- );
- if (_round(_referenceFocalPoint) != _round(focalPointSceneCheck)) {
- _referenceFocalPoint = focalPointSceneCheck;
- }
- return;
-
- case _GestureType.rotate:
- if (details.rotation == 0.0) {
- return;
- }
- final double desiredRotation = _rotationStart + details.rotation;
- _transformationController.value = _matrixRotate(
- _transformationController.value,
- _currentRotation - desiredRotation,
- details.localFocalPoint,
- );
- _currentRotation = desiredRotation;
- return;
-
- case _GestureType.pan:
- assert(_referenceFocalPoint != null);
- // details may have a change in scale here when scaleEnabled is false.
- // In an effort to keep the behavior similar whether or not scaleEnabled
- // is true, these gestures are thrown away.
- if (details.scale != 1.0) {
- return;
- }
- _panAxis ??= _getPanAxis(_referenceFocalPoint, focalPointScene);
- // Translate so that the same point in the scene is underneath the
- // focal point before and after the movement.
- final Offset translationChange = focalPointScene - _referenceFocalPoint;
- _transformationController.value = _matrixTranslate(
- _transformationController.value,
- translationChange,
- );
- _referenceFocalPoint = _transformationController.toScene(
- details.localFocalPoint,
- );
- return;
- }
- }
-
- // Handle the end of a gesture of _GestureType. All of pan, scale, and rotate
- // are handled with GestureDetector's scale gesture.
- void _onScaleEnd(ScaleEndDetails details) {
- if (widget.onInteractionEnd != null) {
- widget.onInteractionEnd(details);
- }
- _scaleStart = null;
- _rotationStart = null;
- _referenceFocalPoint = null;
-
- _animation?.removeListener(_onAnimate);
- _controller.reset();
-
- if (!_gestureIsSupported(_gestureType)) {
- _panAxis = null;
- return;
- }
-
- // If the scale ended with enough velocity, animate inertial movement.
- if (_gestureType != _GestureType.pan ||
- details.velocity.pixelsPerSecond.distance < kMinFlingVelocity) {
- _panAxis = null;
- return;
- }
-
- final Vector3 translationVector =
- _transformationController.value.getTranslation();
- final Offset translation = Offset(translationVector.x, translationVector.y);
- final FrictionSimulation frictionSimulationX = FrictionSimulation(
- _kDrag,
- translation.dx,
- details.velocity.pixelsPerSecond.dx,
- );
- final FrictionSimulation frictionSimulationY = FrictionSimulation(
- _kDrag,
- translation.dy,
- details.velocity.pixelsPerSecond.dy,
- );
- final double tFinal = _getFinalTime(
- details.velocity.pixelsPerSecond.distance,
- _kDrag,
- );
- _animation = Tween<Offset>(
- begin: translation,
- end: Offset(frictionSimulationX.finalX, frictionSimulationY.finalX),
- ).animate(CurvedAnimation(
- parent: _controller,
- curve: Curves.decelerate,
- ));
- _controller.duration = Duration(milliseconds: (tFinal * 1000).round());
- _animation.addListener(_onAnimate);
- _controller.forward();
- }
-
- // Handle mousewheel scroll events.
- void _receivedPointerSignal(PointerSignalEvent event) {
- if (!_gestureIsSupported(_GestureType.scale)) {
- return;
- }
- if (event is PointerScrollEvent) {
- final RenderBox childRenderBox =
- _childKey.currentContext.findRenderObject() as RenderBox;
- final Size childSize = childRenderBox.size;
- final double scaleChange = 1.0 - event.scrollDelta.dy / childSize.height;
- if (scaleChange == 0.0) {
- return;
- }
- final Offset focalPointScene = _transformationController.toScene(
- event.localPosition,
- );
- _transformationController.value = _matrixScale(
- _transformationController.value,
- scaleChange,
- );
-
- // After scaling, translate such that the event's position is at the
- // same scene point before and after the scale.
- final Offset focalPointSceneScaled = _transformationController.toScene(
- event.localPosition,
- );
- _transformationController.value = _matrixTranslate(
- _transformationController.value,
- focalPointSceneScaled - focalPointScene,
- );
- }
- }
-
- // Handle inertia drag animation.
- void _onAnimate() {
- if (!_controller.isAnimating) {
- _panAxis = null;
- _animation?.removeListener(_onAnimate);
- _animation = null;
- _controller.reset();
- return;
- }
- // Translate such that the resulting translation is _animation.value.
- final Vector3 translationVector =
- _transformationController.value.getTranslation();
- final Offset translation = Offset(translationVector.x, translationVector.y);
- final Offset translationScene = _transformationController.toScene(
- translation,
- );
- final Offset animationScene = _transformationController.toScene(
- _animation.value,
- );
- final Offset translationChangeScene = animationScene - translationScene;
- _transformationController.value = _matrixTranslate(
- _transformationController.value,
- translationChangeScene,
- );
- }
-
- void _onTransformationControllerChange() {
- // A change to the TransformationController's value is a change to the
- // state.
- setState(() {});
- }
-
- @override
- void initState() {
- super.initState();
-
- _transformationController =
- widget.transformationController ?? TransformationController();
- _transformationController.addListener(_onTransformationControllerChange);
- _controller = AnimationController(
- vsync: this,
- );
- }
-
- @override
- void didUpdateWidget(InteractiveViewer oldWidget) {
- super.didUpdateWidget(oldWidget);
- // Handle all cases of needing to dispose and initialize
- // transformationControllers.
- if (oldWidget.transformationController == null) {
- if (widget.transformationController != null) {
- _transformationController
- .removeListener(_onTransformationControllerChange);
- _transformationController.dispose();
- _transformationController = widget.transformationController;
- _transformationController
- .addListener(_onTransformationControllerChange);
- }
- } else {
- if (widget.transformationController == null) {
- _transformationController
- .removeListener(_onTransformationControllerChange);
- _transformationController = TransformationController();
- _transformationController
- .addListener(_onTransformationControllerChange);
- } else if (widget.transformationController !=
- oldWidget.transformationController) {
- _transformationController
- .removeListener(_onTransformationControllerChange);
- _transformationController = widget.transformationController;
- _transformationController
- .addListener(_onTransformationControllerChange);
- }
- }
- }
-
- @override
- void dispose() {
- _controller.dispose();
- _transformationController.removeListener(_onTransformationControllerChange);
- if (widget.transformationController == null) {
- _transformationController.dispose();
- }
- super.dispose();
- }
-
- @override
- Widget build(BuildContext context) {
- Widget child = Transform(
- transform: _transformationController.value,
- child: KeyedSubtree(
- key: _childKey,
- child: widget.child,
- ),
- );
-
- if (!widget.constrained) {
- child = ClipRect(
- child: OverflowBox(
- alignment: Alignment.topLeft,
- minWidth: 0.0,
- minHeight: 0.0,
- maxWidth: double.infinity,
- maxHeight: double.infinity,
- child: child,
- ),
- );
- }
-
- // A GestureDetector allows the detection of panning and zooming gestures on
- // the child.
- return Listener(
- key: _parentKey,
- onPointerSignal: _receivedPointerSignal,
- child: GestureDetector(
- behavior: HitTestBehavior.opaque, // Necessary when panning off screen.
- onScaleEnd: _onScaleEnd,
- onScaleStart: _onScaleStart,
- onScaleUpdate: _onScaleUpdate,
- child: child,
- ),
- );
- }
-}
-
-/// A thin wrapper on [ValueNotifier] whose value is a [Matrix4] representing a
-/// transformation.
-///
-/// The [value] defaults to the identity matrix, which corresponds to no
-/// transformation.
-///
-/// See also:
-///
-/// * [InteractiveViewer.transformationController] for detailed documentation
-/// on how to use TransformationController with [InteractiveViewer].
-class TransformationController extends ValueNotifier<Matrix4> {
- /// Create an instance of [TransformationController].
- ///
- /// The [value] defaults to the identity matrix, which corresponds to no
- /// transformation.
- TransformationController([Matrix4 value])
- : super(value ?? Matrix4.identity());
-
- /// Return the scene point at the given viewport point.
- ///
- /// A viewport point is relative to the parent while a scene point is relative
- /// to the child, regardless of transformation. Calling toScene with a
- /// viewport point essentially returns the scene coordinate that lies
- /// underneath the viewport point given the transform.
- ///
- /// The viewport transforms as the inverse of the child (i.e. moving the child
- /// left is equivalent to moving the viewport right).
- ///
- /// This method is often useful when determining where an event on the parent
- /// occurs on the child. This example shows how to determine where a tap on
- /// the parent occurred on the child.
- ///
- /// ```dart
- /// @override
- /// void build(BuildContext context) {
- /// return GestureDetector(
- /// onTapUp: (TapUpDetails details) {
- /// _childWasTappedAt = _transformationController.toScene(
- /// details.localPosition,
- /// );
- /// },
- /// child: InteractiveViewer(
- /// transformationController: _transformationController,
- /// child: child,
- /// ),
- /// );
- /// }
- /// ```
- Offset toScene(Offset viewportPoint) {
- // On viewportPoint, perform the inverse transformation of the scene to get
- // where the point would be in the scene before the transformation.
- final Matrix4 inverseMatrix = Matrix4.inverted(value);
- final Vector3 untransformed = inverseMatrix.transform3(Vector3(
- viewportPoint.dx,
- viewportPoint.dy,
- 0,
- ));
- return Offset(untransformed.x, untransformed.y);
- }
-}
-
-// A classification of relevant user gestures. Each contiguous user gesture is
-// represented by exactly one _GestureType.
-enum _GestureType {
- pan,
- scale,
- rotate,
-}
-
-// Given a velocity and drag, calculate the time at which motion will come to
-// a stop, within the margin of effectivelyMotionless.
-double _getFinalTime(double velocity, double drag) {
- const double effectivelyMotionless = 10.0;
- return math.log(effectivelyMotionless / velocity) / math.log(drag / 100);
-}
-
-// Return the translation from the given Matrix4 as an Offset.
-Offset _getMatrixTranslation(Matrix4 matrix) {
- final Vector3 nextTranslation = matrix.getTranslation();
- return Offset(nextTranslation.x, nextTranslation.y);
-}
-
-// Transform the four corners of the viewport by the inverse of the given
-// matrix. This gives the viewport after the child has been transformed by the
-// given matrix. The viewport transforms as the inverse of the child (i.e.
-// moving the child left is equivalent to moving the viewport right).
-Quad _transformViewport(Matrix4 matrix, Rect viewport) {
- final Matrix4 inverseMatrix = matrix.clone()..invert();
- return Quad.points(
- inverseMatrix.transform3(Vector3(
- viewport.topLeft.dx,
- viewport.topLeft.dy,
- 0.0,
- )),
- inverseMatrix.transform3(Vector3(
- viewport.topRight.dx,
- viewport.topRight.dy,
- 0.0,
- )),
- inverseMatrix.transform3(Vector3(
- viewport.bottomRight.dx,
- viewport.bottomRight.dy,
- 0.0,
- )),
- inverseMatrix.transform3(Vector3(
- viewport.bottomLeft.dx,
- viewport.bottomLeft.dy,
- 0.0,
- )),
- );
-}
-
-// Find the axis aligned bounding box for the rect rotated about its center by
-// the given amount.
-Quad _getAxisAlignedBoundingBoxWithRotation(Rect rect, double rotation) {
- final Matrix4 rotationMatrix = Matrix4.identity()
- ..translate(rect.size.width / 2, rect.size.height / 2)
- ..rotateZ(rotation)
- ..translate(-rect.size.width / 2, -rect.size.height / 2);
- final Quad boundariesRotated = Quad.points(
- rotationMatrix.transform3(Vector3(rect.left, rect.top, 0.0)),
- rotationMatrix.transform3(Vector3(rect.right, rect.top, 0.0)),
- rotationMatrix.transform3(Vector3(rect.right, rect.bottom, 0.0)),
- rotationMatrix.transform3(Vector3(rect.left, rect.bottom, 0.0)),
- );
- return InteractiveViewer.getAxisAlignedBoundingBox(boundariesRotated);
-}
-
-// Return the amount that viewport lies outside of boundary. If the viewport
-// is completely contained within the boundary (inclusively), then returns
-// Offset.zero.
-Offset _exceedsBy(Quad boundary, Quad viewport) {
- final List<Vector3> viewportPoints = <Vector3>[
- viewport.point0,
- viewport.point1,
- viewport.point2,
- viewport.point3,
- ];
- Offset largestExcess = Offset.zero;
- for (final Vector3 point in viewportPoints) {
- final Vector3 pointInside =
- InteractiveViewer.getNearestPointInside(point, boundary);
- final Offset excess = Offset(
- pointInside.x - point.x,
- pointInside.y - point.y,
- );
- if (excess.dx.abs() > largestExcess.dx.abs()) {
- largestExcess = Offset(excess.dx, largestExcess.dy);
- }
- if (excess.dy.abs() > largestExcess.dy.abs()) {
- largestExcess = Offset(largestExcess.dx, excess.dy);
- }
- }
-
- return _round(largestExcess);
-}
-
-// Round the output values. This works around a precision problem where
-// values that should have been zero were given as within 10^-10 of zero.
-Offset _round(Offset offset) {
- return Offset(
- double.parse(offset.dx.toStringAsFixed(9)),
- double.parse(offset.dy.toStringAsFixed(9)),
- );
-}
-
-// Align the given offset to the given axis by allowing movement only in the
-// axis direction.
-Offset _alignAxis(Offset offset, Axis axis) {
- switch (axis) {
- case Axis.horizontal:
- return Offset(offset.dx, 0.0);
- case Axis.vertical:
- default:
- return Offset(0.0, offset.dy);
- }
-}
-
-// Given two points, return the axis where the distance between the points is
-// greatest. If they are equal, return null.
-Axis _getPanAxis(Offset point1, Offset point2) {
- if (point1 == point2) {
- return null;
- }
- final double x = point2.dx - point1.dx;
- final double y = point2.dy - point1.dy;
- return x.abs() > y.abs() ? Axis.horizontal : Axis.vertical;
-}
diff --git a/lib/screens/graph_view.dart b/lib/screens/graph_view.dart
index da869a06..b7500022 100644
--- a/lib/screens/graph_view.dart
+++ b/lib/screens/graph_view.dart
@@ -3,7 +3,6 @@ import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:gitjournal/core/graph.dart';
-import 'package:gitjournal/core/interactive_viewer.dart' as fork;
import 'package:gitjournal/core/notes_folder_fs.dart';
class GraphViewScreen extends StatefulWidget {
@@ -56,7 +55,7 @@ class GraphView extends StatefulWidget {
class _GraphViewState extends State<GraphView> {
final nodeSize = 50.0;
- fork.TransformationController transformationController;
+ TransformationController transformationController;
@override
void initState() {
@@ -67,7 +66,7 @@ class _GraphViewState extends State<GraphView> {
setState(() {});
});
- transformationController = fork.TransformationController();
+ transformationController = TransformationController();
}
Offset _getLocationPosition(Offset globalPos) {
@@ -143,7 +142,7 @@ class _GraphViewState extends State<GraphView> {
),
);
- return fork.InteractiveViewer(
+ return InteractiveViewer(
child: view,
panEnabled: true,
constrained: false,