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 android.view;
18
19import android.annotation.Nullable;
20import android.graphics.Bitmap;
21import android.graphics.Matrix;
22import android.graphics.Paint;
23import android.graphics.SurfaceTexture;
24
25import com.android.internal.util.VirtualRefBasePtr;
26
27/**
28 * A hardware layer can be used to render graphics operations into a hardware
29 * friendly buffer. For instance, with an OpenGL backend a hardware layer
30 * would use a Frame Buffer Object (FBO.) The hardware layer can be used as
31 * a drawing cache when a complex set of graphics operations needs to be
32 * drawn several times.
33 *
34 * @hide
35 */
36final class HardwareLayer {
37    private ThreadedRenderer mRenderer;
38    private VirtualRefBasePtr mFinalizer;
39
40    private HardwareLayer(ThreadedRenderer renderer, long deferredUpdater) {
41        if (renderer == null || deferredUpdater == 0) {
42            throw new IllegalArgumentException("Either hardware renderer: " + renderer
43                    + " or deferredUpdater: " + deferredUpdater + " is invalid");
44        }
45        mRenderer = renderer;
46        mFinalizer = new VirtualRefBasePtr(deferredUpdater);
47    }
48
49    /**
50     * Update the paint used when drawing this layer.
51     *
52     * @param paint The paint used when the layer is drawn into the destination canvas.
53     * @see View#setLayerPaint(android.graphics.Paint)
54     */
55    public void setLayerPaint(@Nullable Paint paint) {
56        nSetLayerPaint(mFinalizer.get(), paint != null ? paint.getNativeInstance() : 0);
57        mRenderer.pushLayerUpdate(this);
58    }
59
60    /**
61     * Indicates whether this layer can be rendered.
62     *
63     * @return True if the layer can be rendered into, false otherwise
64     */
65    public boolean isValid() {
66        return mFinalizer != null && mFinalizer.get() != 0;
67    }
68
69    /**
70     * Destroys resources without waiting for a GC.
71     */
72    public void destroy() {
73        if (!isValid()) {
74            // Already destroyed
75            return;
76        }
77        mRenderer.onLayerDestroyed(this);
78        mRenderer = null;
79        mFinalizer.release();
80        mFinalizer = null;
81    }
82
83    public long getDeferredLayerUpdater() {
84        return mFinalizer.get();
85    }
86
87    /**
88     * Copies this layer into the specified bitmap.
89     *
90     * @param bitmap The bitmap to copy they layer into
91     *
92     * @return True if the copy was successful, false otherwise
93     */
94    public boolean copyInto(Bitmap bitmap) {
95        return mRenderer.copyLayerInto(this, bitmap);
96    }
97
98    /**
99     * Update the layer's properties. Note that after calling this isValid() may
100     * return false if the requested width/height cannot be satisfied
101     *
102     * @param width The new width of this layer
103     * @param height The new height of this layer
104     * @param isOpaque Whether this layer is opaque
105     *
106     * @return true if the layer's properties will change, false if they already
107     *         match the desired values.
108     */
109    public boolean prepare(int width, int height, boolean isOpaque) {
110        return nPrepare(mFinalizer.get(), width, height, isOpaque);
111    }
112
113    /**
114     * Sets an optional transform on this layer.
115     *
116     * @param matrix The transform to apply to the layer.
117     */
118    public void setTransform(Matrix matrix) {
119        nSetTransform(mFinalizer.get(), matrix.native_instance);
120        mRenderer.pushLayerUpdate(this);
121    }
122
123    /**
124     * Indicates that this layer has lost its texture.
125     */
126    public void detachSurfaceTexture() {
127        mRenderer.detachSurfaceTexture(mFinalizer.get());
128    }
129
130    public long getLayerHandle() {
131        return mFinalizer.get();
132    }
133
134    public void setSurfaceTexture(SurfaceTexture surface) {
135        nSetSurfaceTexture(mFinalizer.get(), surface, false);
136        mRenderer.pushLayerUpdate(this);
137    }
138
139    public void updateSurfaceTexture() {
140        nUpdateSurfaceTexture(mFinalizer.get());
141        mRenderer.pushLayerUpdate(this);
142    }
143
144    static HardwareLayer adoptTextureLayer(ThreadedRenderer renderer, long layer) {
145        return new HardwareLayer(renderer, layer);
146    }
147
148    private static native boolean nPrepare(long layerUpdater, int width, int height, boolean isOpaque);
149    private static native void nSetLayerPaint(long layerUpdater, long paint);
150    private static native void nSetTransform(long layerUpdater, long matrix);
151    private static native void nSetSurfaceTexture(long layerUpdater,
152            SurfaceTexture surface, boolean isAlreadyAttached);
153    private static native void nUpdateSurfaceTexture(long layerUpdater);
154}
155