1/*
2 * Copyright (C) 2009 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 java.io.IOException;
20import java.io.InputStream;
21import java.nio.ByteBuffer;
22import java.nio.ByteOrder;
23import java.nio.FloatBuffer;
24
25import javax.microedition.khronos.egl.EGLConfig;
26import javax.microedition.khronos.opengles.GL10;
27
28import android.content.Context;
29import android.graphics.Bitmap;
30import android.graphics.BitmapFactory;
31import android.opengl.GLES20;
32import android.opengl.GLSurfaceView;
33import android.opengl.GLUtils;
34import android.opengl.Matrix;
35import android.os.SystemClock;
36import android.util.Log;
37
38import com.example.android.apis.R;
39
40class GLES20TriangleRenderer implements GLSurfaceView.Renderer {
41
42    public GLES20TriangleRenderer(Context context) {
43        mContext = context;
44        mTriangleVertices = ByteBuffer.allocateDirect(mTriangleVerticesData.length
45                * FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asFloatBuffer();
46        mTriangleVertices.put(mTriangleVerticesData).position(0);
47    }
48
49    public void onDrawFrame(GL10 glUnused) {
50        // Ignore the passed-in GL10 interface, and use the GLES20
51        // class's static methods instead.
52        GLES20.glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
53        GLES20.glClear( GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);
54        GLES20.glUseProgram(mProgram);
55        checkGlError("glUseProgram");
56
57        GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
58        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureID);
59
60        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
61        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
62                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
63        checkGlError("glVertexAttribPointer maPosition");
64        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
65        GLES20.glEnableVertexAttribArray(maPositionHandle);
66        checkGlError("glEnableVertexAttribArray maPositionHandle");
67        GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
68                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
69        checkGlError("glVertexAttribPointer maTextureHandle");
70        GLES20.glEnableVertexAttribArray(maTextureHandle);
71        checkGlError("glEnableVertexAttribArray maTextureHandle");
72
73        long time = SystemClock.uptimeMillis() % 4000L;
74        float angle = 0.090f * ((int) time);
75        Matrix.setRotateM(mMMatrix, 0, angle, 0, 0, 1.0f);
76        Matrix.multiplyMM(mMVPMatrix, 0, mVMatrix, 0, mMMatrix, 0);
77        Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mMVPMatrix, 0);
78
79        GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
80        GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 3);
81        checkGlError("glDrawArrays");
82    }
83
84    public void onSurfaceChanged(GL10 glUnused, int width, int height) {
85        // Ignore the passed-in GL10 interface, and use the GLES20
86        // class's static methods instead.
87        GLES20.glViewport(0, 0, width, height);
88        float ratio = (float) width / height;
89        Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
90    }
91
92    public void onSurfaceCreated(GL10 glUnused, EGLConfig config) {
93        // Ignore the passed-in GL10 interface, and use the GLES20
94        // class's static methods instead.
95        mProgram = createProgram(mVertexShader, mFragmentShader);
96        if (mProgram == 0) {
97            return;
98        }
99        maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
100        checkGlError("glGetAttribLocation aPosition");
101        if (maPositionHandle == -1) {
102            throw new RuntimeException("Could not get attrib location for aPosition");
103        }
104        maTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTextureCoord");
105        checkGlError("glGetAttribLocation aTextureCoord");
106        if (maTextureHandle == -1) {
107            throw new RuntimeException("Could not get attrib location for aTextureCoord");
108        }
109
110        muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
111        checkGlError("glGetUniformLocation uMVPMatrix");
112        if (muMVPMatrixHandle == -1) {
113            throw new RuntimeException("Could not get attrib location for uMVPMatrix");
114        }
115
116        /*
117         * Create our texture. This has to be done each time the
118         * surface is created.
119         */
120
121        int[] textures = new int[1];
122        GLES20.glGenTextures(1, textures, 0);
123
124        mTextureID = textures[0];
125        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureID);
126
127        GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER,
128                GLES20.GL_NEAREST);
129        GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
130                GLES20.GL_TEXTURE_MAG_FILTER,
131                GLES20.GL_LINEAR);
132
133        GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
134                GLES20.GL_REPEAT);
135        GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
136                GLES20.GL_REPEAT);
137
138        InputStream is = mContext.getResources()
139            .openRawResource(R.raw.robot);
140        Bitmap bitmap;
141        try {
142            bitmap = BitmapFactory.decodeStream(is);
143        } finally {
144            try {
145                is.close();
146            } catch(IOException e) {
147                // Ignore.
148            }
149        }
150
151        GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
152        bitmap.recycle();
153
154        Matrix.setLookAtM(mVMatrix, 0, 0, 0, -5, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
155    }
156
157    private int loadShader(int shaderType, String source) {
158        int shader = GLES20.glCreateShader(shaderType);
159        if (shader != 0) {
160            GLES20.glShaderSource(shader, source);
161            GLES20.glCompileShader(shader);
162            int[] compiled = new int[1];
163            GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
164            if (compiled[0] == 0) {
165                Log.e(TAG, "Could not compile shader " + shaderType + ":");
166                Log.e(TAG, GLES20.glGetShaderInfoLog(shader));
167                GLES20.glDeleteShader(shader);
168                shader = 0;
169            }
170        }
171        return shader;
172    }
173
174    private int createProgram(String vertexSource, String fragmentSource) {
175        int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
176        if (vertexShader == 0) {
177            return 0;
178        }
179
180        int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
181        if (pixelShader == 0) {
182            return 0;
183        }
184
185        int program = GLES20.glCreateProgram();
186        if (program != 0) {
187            GLES20.glAttachShader(program, vertexShader);
188            checkGlError("glAttachShader");
189            GLES20.glAttachShader(program, pixelShader);
190            checkGlError("glAttachShader");
191            GLES20.glLinkProgram(program);
192            int[] linkStatus = new int[1];
193            GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
194            if (linkStatus[0] != GLES20.GL_TRUE) {
195                Log.e(TAG, "Could not link program: ");
196                Log.e(TAG, GLES20.glGetProgramInfoLog(program));
197                GLES20.glDeleteProgram(program);
198                program = 0;
199            }
200        }
201        return program;
202    }
203
204    private void checkGlError(String op) {
205        int error;
206        while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
207            Log.e(TAG, op + ": glError " + error);
208            throw new RuntimeException(op + ": glError " + error);
209        }
210    }
211
212    private static final int FLOAT_SIZE_BYTES = 4;
213    private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
214    private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
215    private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
216    private final float[] mTriangleVerticesData = {
217            // X, Y, Z, U, V
218            -1.0f, -0.5f, 0, -0.5f, 0.0f,
219            1.0f, -0.5f, 0, 1.5f, -0.0f,
220            0.0f,  1.11803399f, 0, 0.5f,  1.61803399f };
221
222    private FloatBuffer mTriangleVertices;
223
224    private final String mVertexShader =
225        "uniform mat4 uMVPMatrix;\n" +
226        "attribute vec4 aPosition;\n" +
227        "attribute vec2 aTextureCoord;\n" +
228        "varying vec2 vTextureCoord;\n" +
229        "void main() {\n" +
230        "  gl_Position = uMVPMatrix * aPosition;\n" +
231        "  vTextureCoord = aTextureCoord;\n" +
232        "}\n";
233
234    private final String mFragmentShader =
235        "precision mediump float;\n" +
236        "varying vec2 vTextureCoord;\n" +
237        "uniform sampler2D sTexture;\n" +
238        "void main() {\n" +
239        "  gl_FragColor = texture2D(sTexture, vTextureCoord);\n" +
240        "}\n";
241
242    private float[] mMVPMatrix = new float[16];
243    private float[] mProjMatrix = new float[16];
244    private float[] mMMatrix = new float[16];
245    private float[] mVMatrix = new float[16];
246
247    private int mProgram;
248    private int mTextureID;
249    private int muMVPMatrixHandle;
250    private int maPositionHandle;
251    private int maTextureHandle;
252
253    private Context mContext;
254    private static String TAG = "GLES20TriangleRenderer";
255}
256