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