1/*
2 * Copyright (C) 2012 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.renderscript;
18
19/**
20 * Intrinsic for applying a per-channel lookup table. Each
21 * channel of the input has an independant lookup table. The
22 * tables are 256 entries in size and can cover the full value
23 * range of {@link Element#U8_4}.
24 **/
25public final class ScriptIntrinsicLUT extends ScriptIntrinsic {
26    private final Matrix4f mMatrix = new Matrix4f();
27    private Allocation mTables;
28    private final byte mCache[] = new byte[1024];
29    private boolean mDirty = true;
30
31    private ScriptIntrinsicLUT(long id, RenderScript rs) {
32        super(id, rs);
33        mTables = Allocation.createSized(rs, Element.U8(rs), 1024);
34        for (int ct=0; ct < 256; ct++) {
35            mCache[ct] = (byte)ct;
36            mCache[ct + 256] = (byte)ct;
37            mCache[ct + 512] = (byte)ct;
38            mCache[ct + 768] = (byte)ct;
39        }
40        setVar(0, mTables);
41    }
42
43    /**
44     * Supported elements types are {@link Element#U8_4}
45     *
46     * The defaults tables are identity.
47     *
48     * @param rs The RenderScript context
49     * @param e Element type for intputs and outputs
50     *
51     * @return ScriptIntrinsicLUT
52     */
53    public static ScriptIntrinsicLUT create(RenderScript rs, Element e) {
54        long id = rs.nScriptIntrinsicCreate(3, e.getID(rs));
55        return new ScriptIntrinsicLUT(id, rs);
56
57    }
58
59
60    private void validate(int index, int value) {
61        if (index < 0 || index > 255) {
62            throw new RSIllegalArgumentException("Index out of range (0-255).");
63        }
64        if (value < 0 || value > 255) {
65            throw new RSIllegalArgumentException("Value out of range (0-255).");
66        }
67    }
68
69    /**
70     * Set an entry in the red channel lookup table
71     *
72     * @param index Must be 0-255
73     * @param value Must be 0-255
74     */
75    public void setRed(int index, int value) {
76        validate(index, value);
77        mCache[index] = (byte)value;
78        mDirty = true;
79    }
80
81    /**
82     * Set an entry in the green channel lookup table
83     *
84     * @param index Must be 0-255
85     * @param value Must be 0-255
86     */
87    public void setGreen(int index, int value) {
88        validate(index, value);
89        mCache[index+256] = (byte)value;
90        mDirty = true;
91    }
92
93    /**
94     * Set an entry in the blue channel lookup table
95     *
96     * @param index Must be 0-255
97     * @param value Must be 0-255
98     */
99    public void setBlue(int index, int value) {
100        validate(index, value);
101        mCache[index+512] = (byte)value;
102        mDirty = true;
103    }
104
105    /**
106     * Set an entry in the alpha channel lookup table
107     *
108     * @param index Must be 0-255
109     * @param value Must be 0-255
110     */
111    public void setAlpha(int index, int value) {
112        validate(index, value);
113        mCache[index+768] = (byte)value;
114        mDirty = true;
115    }
116
117    /**
118     * Invoke the kernel and apply the lookup to each cell of ain
119     * and copy to aout.
120     *
121     * @param ain Input allocation
122     * @param aout Output allocation
123     */
124    public void forEach(Allocation ain, Allocation aout) {
125        forEach(ain, aout, null);
126    }
127
128    /**
129     * Invoke the kernel and apply the lookup to each cell of ain
130     * and copy to aout.
131     *
132     * @param ain Input allocation
133     * @param aout Output allocation
134     * @param opt Options for clipping
135     */
136    public void forEach(Allocation ain, Allocation aout, Script.LaunchOptions opt) {
137        if (mDirty) {
138            mDirty = false;
139            mTables.copyFromUnchecked(mCache);
140        }
141        forEach(0, ain, aout, null, opt);
142    }
143
144    /**
145     * Get a KernelID for this intrinsic kernel.
146     *
147     * @return Script.KernelID The KernelID object.
148     */
149    public Script.KernelID getKernelID() {
150        return createKernelID(0, 3, null, null);
151    }
152}
153
154