1/*
2 * Copyright (C) 2011 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
17package com.android.server.wm;
18
19import static com.android.server.wm.WindowManagerDebugConfig.TAG_WM;
20
21import android.graphics.Canvas;
22import android.graphics.Paint;
23import android.graphics.PixelFormat;
24import android.graphics.PorterDuff;
25import android.graphics.Rect;
26import android.graphics.Typeface;
27import android.graphics.Paint.FontMetricsInt;
28import android.util.DisplayMetrics;
29import android.util.Log;
30import android.util.TypedValue;
31import android.view.Display;
32import android.view.Surface.OutOfResourcesException;
33import android.view.Surface;
34import android.view.SurfaceControl;
35import android.view.SurfaceSession;
36
37/**
38 * Displays a watermark on top of the window manager's windows.
39 */
40class Watermark {
41    private final Display mDisplay;
42    private final String[] mTokens;
43    private final String mText;
44    private final Paint mTextPaint;
45    private final int mTextWidth;
46    private final int mTextHeight;
47    private final int mDeltaX;
48    private final int mDeltaY;
49
50    private final SurfaceControl mSurfaceControl;
51    private final Surface mSurface = new Surface();
52    private int mLastDW;
53    private int mLastDH;
54    private boolean mDrawNeeded;
55
56    Watermark(Display display, DisplayMetrics dm, SurfaceSession session, String[] tokens) {
57        if (false) {
58            Log.i(TAG_WM, "*********************** WATERMARK");
59            for (int i=0; i<tokens.length; i++) {
60                Log.i(TAG_WM, "  TOKEN #" + i + ": " + tokens[i]);
61            }
62        }
63
64        mDisplay = display;
65        mTokens = tokens;
66
67        StringBuilder builder = new StringBuilder(32);
68        int len = mTokens[0].length();
69        len = len & ~1;
70        for (int i=0; i<len; i+=2) {
71            int c1 = mTokens[0].charAt(i);
72            int c2 = mTokens[0].charAt(i+1);
73            if (c1 >= 'a' && c1 <= 'f') c1 = c1 - 'a' + 10;
74            else if (c1 >= 'A' && c1 <= 'F') c1 = c1 - 'A' + 10;
75            else c1 -= '0';
76            if (c2 >= 'a' && c2 <= 'f') c2 = c2 - 'a' + 10;
77            else if (c2 >= 'A' && c2 <= 'F') c2 = c2 - 'A' + 10;
78            else c2 -= '0';
79            builder.append((char)(255-((c1*16)+c2)));
80        }
81        mText = builder.toString();
82        if (false) {
83            Log.i(TAG_WM, "Final text: " + mText);
84        }
85
86        int fontSize = WindowManagerService.getPropertyInt(tokens, 1,
87                TypedValue.COMPLEX_UNIT_DIP, 20, dm);
88
89        mTextPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
90        mTextPaint.setTextSize(fontSize);
91        mTextPaint.setTypeface(Typeface.create(Typeface.SANS_SERIF, Typeface.BOLD));
92
93        FontMetricsInt fm = mTextPaint.getFontMetricsInt();
94        mTextWidth = (int)mTextPaint.measureText(mText);
95        mTextHeight = fm.descent - fm.ascent;
96
97        mDeltaX = WindowManagerService.getPropertyInt(tokens, 2,
98                TypedValue.COMPLEX_UNIT_PX, mTextWidth*2, dm);
99        mDeltaY = WindowManagerService.getPropertyInt(tokens, 3,
100                TypedValue.COMPLEX_UNIT_PX, mTextHeight*3, dm);
101        int shadowColor = WindowManagerService.getPropertyInt(tokens, 4,
102                TypedValue.COMPLEX_UNIT_PX, 0xb0000000, dm);
103        int color = WindowManagerService.getPropertyInt(tokens, 5,
104                TypedValue.COMPLEX_UNIT_PX, 0x60ffffff, dm);
105        int shadowRadius = WindowManagerService.getPropertyInt(tokens, 6,
106                TypedValue.COMPLEX_UNIT_PX, 7, dm);
107        int shadowDx = WindowManagerService.getPropertyInt(tokens, 8,
108                TypedValue.COMPLEX_UNIT_PX, 0, dm);
109        int shadowDy = WindowManagerService.getPropertyInt(tokens, 9,
110                TypedValue.COMPLEX_UNIT_PX, 0, dm);
111
112        mTextPaint.setColor(color);
113        mTextPaint.setShadowLayer(shadowRadius, shadowDx, shadowDy, shadowColor);
114
115        SurfaceControl ctrl = null;
116        try {
117            ctrl = new SurfaceControl(session, "WatermarkSurface",
118                    1, 1, PixelFormat.TRANSLUCENT, SurfaceControl.HIDDEN);
119            ctrl.setLayerStack(mDisplay.getLayerStack());
120            ctrl.setLayer(WindowManagerService.TYPE_LAYER_MULTIPLIER*100);
121            ctrl.setPosition(0, 0);
122            ctrl.show();
123            mSurface.copyFrom(ctrl);
124        } catch (OutOfResourcesException e) {
125        }
126        mSurfaceControl = ctrl;
127    }
128
129    void positionSurface(int dw, int dh) {
130        if (mLastDW != dw || mLastDH != dh) {
131            mLastDW = dw;
132            mLastDH = dh;
133            mSurfaceControl.setSize(dw, dh);
134            mDrawNeeded = true;
135        }
136    }
137
138    void drawIfNeeded() {
139        if (mDrawNeeded) {
140            final int dw = mLastDW;
141            final int dh = mLastDH;
142
143            mDrawNeeded = false;
144            Rect dirty = new Rect(0, 0, dw, dh);
145            Canvas c = null;
146            try {
147                c = mSurface.lockCanvas(dirty);
148            } catch (IllegalArgumentException e) {
149            } catch (Surface.OutOfResourcesException e) {
150            }
151            if (c != null) {
152                c.drawColor(0, PorterDuff.Mode.CLEAR);
153
154                int deltaX = mDeltaX;
155                int deltaY = mDeltaY;
156
157                // deltaX shouldn't be close to a round fraction of our
158                // x step, or else things will line up too much.
159                int div = (dw+mTextWidth)/deltaX;
160                int rem = (dw+mTextWidth) - (div*deltaX);
161                int qdelta = deltaX/4;
162                if (rem < qdelta || rem > (deltaX-qdelta)) {
163                    deltaX += deltaX/3;
164                }
165
166                int y = -mTextHeight;
167                int x = -mTextWidth;
168                while (y < (dh+mTextHeight)) {
169                    c.drawText(mText, x, y, mTextPaint);
170                    x += deltaX;
171                    if (x >= dw) {
172                        x -= (dw+mTextWidth);
173                        y += deltaY;
174                    }
175                }
176                mSurface.unlockCanvasAndPost(c);
177            }
178        }
179    }
180}
181