1/*
2 * Copyright (C) 2007 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 com.example.android.apis.graphics;
18
19import javax.microedition.khronos.egl.EGLConfig;
20import javax.microedition.khronos.opengles.GL10;
21
22import android.opengl.GLSurfaceView;
23
24/**
25 * Render a pair of tumbling cubes.
26 */
27
28public class CubeRenderer implements GLSurfaceView.Renderer {
29    public CubeRenderer(boolean useTranslucentBackground) {
30        mTranslucentBackground = useTranslucentBackground;
31        mCube = new Cube();
32    }
33
34    public void onDrawFrame(GL10 gl) {
35        /*
36         * Usually, the first thing one might want to do is to clear
37         * the screen. The most efficient way of doing this is to use
38         * glClear().
39         */
40
41        gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
42
43        /*
44         * Now we're ready to draw some 3D objects
45         */
46
47        gl.glMatrixMode(GL10.GL_MODELVIEW);
48        gl.glLoadIdentity();
49        gl.glTranslatef(0, 0, -3.0f);
50        gl.glRotatef(mAngle,        0, 1, 0);
51        gl.glRotatef(mAngle*0.25f,  1, 0, 0);
52
53        gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
54        gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
55
56        mCube.draw(gl);
57
58        gl.glRotatef(mAngle*2.0f, 0, 1, 1);
59        gl.glTranslatef(0.5f, 0.5f, 0.5f);
60
61        mCube.draw(gl);
62
63        mAngle += 1.2f;
64    }
65
66    public void onSurfaceChanged(GL10 gl, int width, int height) {
67         gl.glViewport(0, 0, width, height);
68
69         /*
70          * Set our projection matrix. This doesn't have to be done
71          * each time we draw, but usually a new projection needs to
72          * be set when the viewport is resized.
73          */
74
75         float ratio = (float) width / height;
76         gl.glMatrixMode(GL10.GL_PROJECTION);
77         gl.glLoadIdentity();
78         gl.glFrustumf(-ratio, ratio, -1, 1, 1, 10);
79    }
80
81    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
82        /*
83         * By default, OpenGL enables features that improve quality
84         * but reduce performance. One might want to tweak that
85         * especially on software renderer.
86         */
87        gl.glDisable(GL10.GL_DITHER);
88
89        /*
90         * Some one-time OpenGL initialization can be made here
91         * probably based on features of this particular context
92         */
93         gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT,
94                 GL10.GL_FASTEST);
95
96         if (mTranslucentBackground) {
97             gl.glClearColor(0,0,0,0);
98         } else {
99             gl.glClearColor(1,1,1,1);
100         }
101         gl.glEnable(GL10.GL_CULL_FACE);
102         gl.glShadeModel(GL10.GL_SMOOTH);
103         gl.glEnable(GL10.GL_DEPTH_TEST);
104    }
105    private boolean mTranslucentBackground;
106    private Cube mCube;
107    private float mAngle;
108}
109