1/*
2 * Copyright (C) 2006 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.graphics;
18
19/**
20 * Shader is the based class for objects that return horizontal spans of colors
21 * during drawing. A subclass of Shader is installed in a Paint calling
22 * paint.setShader(shader). After that any object (other than a bitmap) that is
23 * drawn with that paint will get its color(s) from the shader.
24 */
25public class Shader {
26    /**
27     * This is set by subclasses, but don't make it public.
28     *
29     * @hide
30     */
31    public int native_instance;
32    /**
33     * @hide
34     */
35    public int native_shader;
36
37    private Matrix mLocalMatrix;
38
39    public enum TileMode {
40        /**
41         * replicate the edge color if the shader draws outside of its
42         * original bounds
43         */
44        CLAMP   (0),
45        /**
46         * repeat the shader's image horizontally and vertically
47         */
48        REPEAT  (1),
49        /**
50         * repeat the shader's image horizontally and vertically, alternating
51         * mirror images so that adjacent images always seam
52         */
53        MIRROR  (2);
54
55        TileMode(int nativeInt) {
56            this.nativeInt = nativeInt;
57        }
58        final int nativeInt;
59    }
60
61    /**
62     * Return true if the shader has a non-identity local matrix.
63     * @param localM If not null, it is set to the shader's local matrix.
64     * @return true if the shader has a non-identity local matrix
65     */
66    public boolean getLocalMatrix(Matrix localM) {
67        if (mLocalMatrix != null) {
68            localM.set(mLocalMatrix);
69            return !mLocalMatrix.isIdentity();
70        }
71        return false;
72    }
73
74    /**
75     * Set the shader's local matrix. Passing null will reset the shader's
76     * matrix to identity
77     * @param localM The shader's new local matrix, or null to specify identity
78     */
79    public void setLocalMatrix(Matrix localM) {
80        mLocalMatrix = localM;
81        nativeSetLocalMatrix(native_instance, native_shader,
82                localM == null ? 0 : localM.native_instance);
83    }
84
85    protected void finalize() throws Throwable {
86        try {
87            super.finalize();
88        } finally {
89            nativeDestructor(native_instance, native_shader);
90        }
91    }
92
93    private static native void nativeDestructor(int native_shader, int native_skiaShader);
94    private static native void nativeSetLocalMatrix(int native_shader,
95            int native_skiaShader, int matrix_instance);
96}
97