1 /*
2  * Copyright (C) 2010 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.gallery3d.glrenderer;
18 
19 import android.graphics.Bitmap;
20 import android.graphics.Bitmap.Config;
21 import android.graphics.Canvas;
22 
23 // CanvasTexture is a texture whose content is the drawing on a Canvas.
24 // The subclasses should override onDraw() to draw on the bitmap.
25 // By default CanvasTexture is not opaque.
26 abstract class CanvasTexture extends UploadedTexture {
27     protected Canvas mCanvas;
28     private final Config mConfig;
29 
CanvasTexture(int width, int height)30     public CanvasTexture(int width, int height) {
31         mConfig = Config.ARGB_8888;
32         setSize(width, height);
33         setOpaque(false);
34     }
35 
36     @Override
onGetBitmap()37     protected Bitmap onGetBitmap() {
38         Bitmap bitmap = Bitmap.createBitmap(mWidth, mHeight, mConfig);
39         mCanvas = new Canvas(bitmap);
40         onDraw(mCanvas, bitmap);
41         return bitmap;
42     }
43 
44     @Override
onFreeBitmap(Bitmap bitmap)45     protected void onFreeBitmap(Bitmap bitmap) {
46         if (!inFinalizer()) {
47             bitmap.recycle();
48         }
49     }
50 
onDraw(Canvas canvas, Bitmap backing)51     abstract protected void onDraw(Canvas canvas, Bitmap backing);
52 }
53