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