1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package com.example.android.curvedmotion;
17 
18 /**
19  * A class that holds information about a location and how the path should get to that
20  * location from the previous path location (if any). Any PathPoint holds the information for
21  * its location as well as the instructions on how to traverse the preceding interval from the
22  * previous location.
23  */
24 public class PathPoint {
25 
26     /**
27      * The possible path operations that describe how to move from a preceding PathPoint to the
28      * location described by this PathPoint.
29      */
30     public static final int MOVE = 0;
31     public static final int LINE = 1;
32     public static final int CURVE = 2;
33 
34     /**
35      * The location of this PathPoint
36      */
37     float mX, mY;
38 
39     /**
40      * The first control point, if any, for a PathPoint of type CURVE
41      */
42     float mControl0X, mControl0Y;
43 
44     /**
45      * The second control point, if any, for a PathPoint of type CURVE
46      */
47     float mControl1X, mControl1Y;
48 
49     /**
50      * The motion described by the path to get from the previous PathPoint in an AnimatorPath
51      * to the location of this PathPoint. This can be one of MOVE, LINE, or CURVE.
52      */
53     int mOperation;
54 
55 
56 
57     /**
58      * Line/Move constructor
59      */
PathPoint(int operation, float x, float y)60     private PathPoint(int operation, float x, float y) {
61         mOperation = operation;
62         mX = x;
63         mY = y;
64     }
65 
66     /**
67      * Curve constructor
68      */
PathPoint(float c0X, float c0Y, float c1X, float c1Y, float x, float y)69     private PathPoint(float c0X, float c0Y, float c1X, float c1Y, float x, float y) {
70         mControl0X = c0X;
71         mControl0Y = c0Y;
72         mControl1X = c1X;
73         mControl1Y = c1Y;
74         mX = x;
75         mY = y;
76         mOperation = CURVE;
77     }
78 
79     /**
80      * Constructs and returns a PathPoint object that describes a line to the given xy location.
81      */
lineTo(float x, float y)82     public static PathPoint lineTo(float x, float y) {
83         return new PathPoint(LINE, x, y);
84     }
85 
86     /**
87      * Constructs and returns a PathPoint object that describes a curve to the given xy location
88      * with the control points at c0 and c1.
89      */
curveTo(float c0X, float c0Y, float c1X, float c1Y, float x, float y)90     public static PathPoint curveTo(float c0X, float c0Y, float c1X, float c1Y, float x, float y) {
91         return new PathPoint(c0X,  c0Y, c1X, c1Y, x, y);
92     }
93 
94     /**
95      * Constructs and returns a PathPoint object that describes a discontinuous move to the given
96      * xy location.
97      */
moveTo(float x, float y)98     public static PathPoint moveTo(float x, float y) {
99         return new PathPoint(MOVE, x, y);
100     }
101 }
102