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.support.v8.renderscript;
18
19import android.util.Log;
20
21/**
22 * Intrinsic for applying a per-channel lookup table. Each
23 * channel of the input has an independant lookup table. The
24 * tables are 256 entries in size and can cover the full value
25 * range of {@link Element#U8_4}.
26 **/
27public final class ScriptIntrinsicLUT extends ScriptIntrinsic {
28    private final Matrix4f mMatrix = new Matrix4f();
29    private Allocation mTables;
30    private final byte mCache[] = new byte[1024];
31    private boolean mDirty = true;
32
33    private ScriptIntrinsicLUT(int id, RenderScript rs) {
34        super(id, rs);
35        mTables = Allocation.createSized(rs, Element.U8(rs), 1024);
36        for (int ct=0; ct < 256; ct++) {
37            mCache[ct] = (byte)ct;
38            mCache[ct + 256] = (byte)ct;
39            mCache[ct + 512] = (byte)ct;
40            mCache[ct + 768] = (byte)ct;
41        }
42        bindAllocation(mTables, 0);
43    }
44
45    /**
46     * Supported elements types are {@link Element#U8_4}
47     *
48     * The defaults tables are identity.
49     *
50     * @param rs The Renderscript context
51     * @param e Element type for intputs and outputs
52     *
53     * @return ScriptIntrinsicLUT
54     */
55    public static ScriptIntrinsicLUT create(RenderScript rs, Element e) {
56        int id = rs.nScriptIntrinsicCreate(3, e.getID(rs));
57        return new ScriptIntrinsicLUT(id, rs);
58
59    }
60
61
62    private void validate(int index, int value) {
63        if (index < 0 || index > 255) {
64            throw new RSIllegalArgumentException("Index out of range (0-255).");
65        }
66        if (value < 0 || value > 255) {
67            throw new RSIllegalArgumentException("Value out of range (0-255).");
68        }
69    }
70
71    /**
72     * Set an entry in the red channel lookup table
73     *
74     * @param index Must be 0-255
75     * @param value Must be 0-255
76     */
77    public void setRed(int index, int value) {
78        validate(index, value);
79        mCache[index] = (byte)value;
80        mDirty = true;
81    }
82
83    /**
84     * Set an entry in the green channel lookup table
85     *
86     * @param index Must be 0-255
87     * @param value Must be 0-255
88     */
89    public void setGreen(int index, int value) {
90        validate(index, value);
91        mCache[index+256] = (byte)value;
92        mDirty = true;
93    }
94
95    /**
96     * Set an entry in the blue channel lookup table
97     *
98     * @param index Must be 0-255
99     * @param value Must be 0-255
100     */
101    public void setBlue(int index, int value) {
102        validate(index, value);
103        mCache[index+512] = (byte)value;
104        mDirty = true;
105    }
106
107    /**
108     * Set an entry in the alpha channel lookup table
109     *
110     * @param index Must be 0-255
111     * @param value Must be 0-255
112     */
113    public void setAlpha(int index, int value) {
114        validate(index, value);
115        mCache[index+768] = (byte)value;
116        mDirty = true;
117    }
118
119
120    /**
121     * Invoke the kernel and apply the lookup to each cell of ain
122     * and copy to aout.
123     *
124     * @param ain Input allocation
125     * @param aout Output allocation
126     */
127    public void forEach(Allocation ain, Allocation aout) {
128        if (mDirty) {
129            mDirty = false;
130            mTables.copyFromUnchecked(mCache);
131        }
132        forEach(0, ain, aout, null);
133    }
134
135    /**
136     * Get a KernelID for this intrinsic kernel.
137     *
138     * @return Script.KernelID The KernelID object.
139     */
140    public Script.KernelID getKernelID() {
141        return createKernelID(0, 3, null, null);
142    }
143}
144
145