1 /*
2  * Copyright (C) 2006 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 
17 package android.view.animation;
18 
19 import android.annotation.FloatRange;
20 import android.compat.annotation.UnsupportedAppUsage;
21 import android.graphics.Insets;
22 import android.graphics.Matrix;
23 import android.graphics.Rect;
24 
25 import java.io.PrintWriter;
26 
27 /**
28  * Defines the transformation to be applied at
29  * one point in time of an Animation.
30  *
31  */
32 public class Transformation {
33     /**
34      * Indicates a transformation that has no effect (alpha = 1 and identity matrix.)
35      */
36     public static final int TYPE_IDENTITY = 0x0;
37     /**
38      * Indicates a transformation that applies an alpha only (uses an identity matrix.)
39      */
40     public static final int TYPE_ALPHA = 0x1;
41     /**
42      * Indicates a transformation that applies a matrix only (alpha = 1.)
43      */
44     public static final int TYPE_MATRIX = 0x2;
45     /**
46      * Indicates a transformation that applies an alpha and a matrix.
47      */
48     public static final int TYPE_BOTH = TYPE_ALPHA | TYPE_MATRIX;
49 
50     protected Matrix mMatrix;
51     protected float mAlpha;
52     protected int mTransformationType;
53 
54     private boolean mHasClipRect;
55     private Rect mClipRect = new Rect();
56 
57     private Insets mInsets = Insets.NONE;
58 
59     /**
60      * Creates a new transformation with alpha = 1 and the identity matrix.
61      */
Transformation()62     public Transformation() {
63         clear();
64     }
65 
66     /**
67      * Reset the transformation to a state that leaves the object
68      * being animated in an unmodified state. The transformation type is
69      * {@link #TYPE_BOTH} by default.
70      */
clear()71     public void clear() {
72         if (mMatrix == null) {
73             mMatrix = new Matrix();
74         } else {
75             mMatrix.reset();
76         }
77         mClipRect.setEmpty();
78         mHasClipRect = false;
79         mAlpha = 1.0f;
80         mTransformationType = TYPE_BOTH;
81     }
82 
83     /**
84      * Indicates the nature of this transformation.
85      *
86      * @return {@link #TYPE_ALPHA}, {@link #TYPE_MATRIX},
87      *         {@link #TYPE_BOTH} or {@link #TYPE_IDENTITY}.
88      */
getTransformationType()89     public int getTransformationType() {
90         return mTransformationType;
91     }
92 
93     /**
94      * Sets the transformation type.
95      *
96      * @param transformationType One of {@link #TYPE_ALPHA},
97      *        {@link #TYPE_MATRIX}, {@link #TYPE_BOTH} or
98      *        {@link #TYPE_IDENTITY}.
99      */
setTransformationType(int transformationType)100     public void setTransformationType(int transformationType) {
101         mTransformationType = transformationType;
102     }
103 
104     /**
105      * Clones the specified transformation.
106      *
107      * @param t The transformation to clone.
108      */
set(Transformation t)109     public void set(Transformation t) {
110         mAlpha = t.getAlpha();
111         mMatrix.set(t.getMatrix());
112         if (t.mHasClipRect) {
113             setClipRect(t.getClipRect());
114         } else {
115             mHasClipRect = false;
116             mClipRect.setEmpty();
117         }
118         mTransformationType = t.getTransformationType();
119     }
120 
121     /**
122      * Apply this Transformation to an existing Transformation, e.g. apply
123      * a scale effect to something that has already been rotated.
124      * @param t
125      */
compose(Transformation t)126     public void compose(Transformation t) {
127         mAlpha *= t.getAlpha();
128         mMatrix.preConcat(t.getMatrix());
129         if (t.mHasClipRect) {
130             Rect bounds = t.getClipRect();
131             if (mHasClipRect) {
132                 setClipRect(mClipRect.left + bounds.left, mClipRect.top + bounds.top,
133                         mClipRect.right + bounds.right, mClipRect.bottom + bounds.bottom);
134             } else {
135                 setClipRect(bounds);
136             }
137         }
138         setInsets(Insets.add(getInsets(), t.getInsets()));
139     }
140 
141     /**
142      * Like {@link #compose(Transformation)} but does this.postConcat(t) of
143      * the transformation matrix.
144      * @hide
145      */
postCompose(Transformation t)146     public void postCompose(Transformation t) {
147         mAlpha *= t.getAlpha();
148         mMatrix.postConcat(t.getMatrix());
149         if (t.mHasClipRect) {
150             Rect bounds = t.getClipRect();
151             if (mHasClipRect) {
152                 setClipRect(mClipRect.left + bounds.left, mClipRect.top + bounds.top,
153                         mClipRect.right + bounds.right, mClipRect.bottom + bounds.bottom);
154             } else {
155                 setClipRect(bounds);
156             }
157         }
158     }
159 
160     /**
161      * @return The 3x3 Matrix representing the transformation to apply to the
162      * coordinates of the object being animated
163      */
getMatrix()164     public Matrix getMatrix() {
165         return mMatrix;
166     }
167 
168     /**
169      * Sets the degree of transparency
170      * @param alpha 1.0 means fully opaque and 0.0 means fully transparent
171      */
setAlpha(@loatRangefrom=0.0, to=1.0) float alpha)172     public void setAlpha(@FloatRange(from=0.0, to=1.0) float alpha) {
173         mAlpha = alpha;
174     }
175 
176     /**
177      * @return The degree of transparency
178      */
getAlpha()179     public float getAlpha() {
180         return mAlpha;
181     }
182 
183     /**
184      * Sets the current Transform's clip rect
185      * @hide
186      */
setClipRect(Rect r)187     public void setClipRect(Rect r) {
188         setClipRect(r.left, r.top, r.right, r.bottom);
189     }
190 
191     /**
192      * Sets the current Transform's clip rect
193      * @hide
194      */
setClipRect(int l, int t, int r, int b)195     public void setClipRect(int l, int t, int r, int b) {
196         mClipRect.set(l, t, r, b);
197         mHasClipRect = true;
198     }
199 
200     /**
201      * Returns the current Transform's clip rect
202      * @hide
203      */
getClipRect()204     public Rect getClipRect() {
205         return mClipRect;
206     }
207 
208     /**
209      * Returns whether the current Transform's clip rect is set
210      * @hide
211      */
hasClipRect()212     public boolean hasClipRect() {
213         return mHasClipRect;
214     }
215 
216     /**
217      * Sets the current Transform's insets
218      * @hide
219      */
setInsets(Insets insets)220     public void setInsets(Insets insets) {
221         mInsets = insets;
222     }
223 
224     /**
225      * Sets the current Transform's insets
226      * @hide
227      */
setInsets(int left, int top, int right, int bottom)228     public void setInsets(int left, int top, int right, int bottom) {
229         mInsets = Insets.of(left, top, right, bottom);
230     }
231 
232     /**
233      * Returns the current Transform's outset rect
234      * @hide
235      */
getInsets()236     public Insets getInsets() {
237         return mInsets;
238     }
239 
240     @Override
toString()241     public String toString() {
242         StringBuilder sb = new StringBuilder(64);
243         sb.append("Transformation");
244         toShortString(sb);
245         return sb.toString();
246     }
247 
248     /**
249      * Return a string representation of the transformation in a compact form.
250      */
toShortString()251     public String toShortString() {
252         StringBuilder sb = new StringBuilder(64);
253         toShortString(sb);
254         return sb.toString();
255     }
256 
257     /**
258      * @hide
259      */
toShortString(StringBuilder sb)260     public void toShortString(StringBuilder sb) {
261         sb.append("{alpha="); sb.append(mAlpha);
262         sb.append(" matrix="); sb.append(mMatrix.toShortString());
263         sb.append('}');
264     }
265 
266     /**
267      * Print short string, to optimize dumping.
268      * @hide
269      */
270     @UnsupportedAppUsage
printShortString(PrintWriter pw)271     public void printShortString(PrintWriter pw) {
272         pw.print("{alpha="); pw.print(mAlpha);
273         pw.print(" matrix=");
274         mMatrix.dump(pw);
275         pw.print('}');
276     }
277 }
278