1 /*
2  * Copyright (C) 2011 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 
17 package com.example.android.basicglsurfaceview;
18 
19 import java.io.IOException;
20 import java.io.InputStream;
21 import java.nio.ByteBuffer;
22 import java.nio.ByteOrder;
23 import java.nio.FloatBuffer;
24 
25 import javax.microedition.khronos.egl.EGLConfig;
26 import javax.microedition.khronos.opengles.GL10;
27 
28 import android.content.Context;
29 import android.graphics.Bitmap;
30 import android.graphics.BitmapFactory;
31 import android.opengl.GLES20;
32 import android.opengl.GLSurfaceView;
33 import android.opengl.GLUtils;
34 import android.opengl.Matrix;
35 import android.os.SystemClock;
36 import android.util.Log;
37 
38 class GLES20TriangleRenderer implements GLSurfaceView.Renderer {
39 
GLES20TriangleRenderer(Context context)40     public GLES20TriangleRenderer(Context context) {
41         mContext = context;
42         mTriangleVertices = ByteBuffer.allocateDirect(mTriangleVerticesData.length
43                 * FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asFloatBuffer();
44         mTriangleVertices.put(mTriangleVerticesData).position(0);
45     }
46 
onDrawFrame(GL10 glUnused)47     public void onDrawFrame(GL10 glUnused) {
48         // Ignore the passed-in GL10 interface, and use the GLES20
49         // class's static methods instead.
50         GLES20.glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
51         GLES20.glClear( GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);
52         GLES20.glUseProgram(mProgram);
53         checkGlError("glUseProgram");
54 
55         GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
56         GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureID);
57 
58         mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
59         GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
60                 TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
61         checkGlError("glVertexAttribPointer maPosition");
62         mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
63         GLES20.glEnableVertexAttribArray(maPositionHandle);
64         checkGlError("glEnableVertexAttribArray maPositionHandle");
65         GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
66                 TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
67         checkGlError("glVertexAttribPointer maTextureHandle");
68         GLES20.glEnableVertexAttribArray(maTextureHandle);
69         checkGlError("glEnableVertexAttribArray maTextureHandle");
70 
71         long time = SystemClock.uptimeMillis() % 4000L;
72         float angle = 0.090f * ((int) time);
73         Matrix.setRotateM(mMMatrix, 0, angle, 0, 0, 1.0f);
74         Matrix.multiplyMM(mMVPMatrix, 0, mVMatrix, 0, mMMatrix, 0);
75         Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mMVPMatrix, 0);
76 
77         GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
78         GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 3);
79         checkGlError("glDrawArrays");
80     }
81 
onSurfaceChanged(GL10 glUnused, int width, int height)82     public void onSurfaceChanged(GL10 glUnused, int width, int height) {
83         // Ignore the passed-in GL10 interface, and use the GLES20
84         // class's static methods instead.
85         GLES20.glViewport(0, 0, width, height);
86         float ratio = (float) width / height;
87         Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
88     }
89 
onSurfaceCreated(GL10 glUnused, EGLConfig config)90     public void onSurfaceCreated(GL10 glUnused, EGLConfig config) {
91         // Ignore the passed-in GL10 interface, and use the GLES20
92         // class's static methods instead.
93         mProgram = createProgram(mVertexShader, mFragmentShader);
94         if (mProgram == 0) {
95             return;
96         }
97         maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
98         checkGlError("glGetAttribLocation aPosition");
99         if (maPositionHandle == -1) {
100             throw new RuntimeException("Could not get attrib location for aPosition");
101         }
102         maTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTextureCoord");
103         checkGlError("glGetAttribLocation aTextureCoord");
104         if (maTextureHandle == -1) {
105             throw new RuntimeException("Could not get attrib location for aTextureCoord");
106         }
107 
108         muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
109         checkGlError("glGetUniformLocation uMVPMatrix");
110         if (muMVPMatrixHandle == -1) {
111             throw new RuntimeException("Could not get attrib location for uMVPMatrix");
112         }
113 
114         /*
115          * Create our texture. This has to be done each time the
116          * surface is created.
117          */
118 
119         int[] textures = new int[1];
120         GLES20.glGenTextures(1, textures, 0);
121 
122         mTextureID = textures[0];
123         GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureID);
124 
125         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER,
126                 GLES20.GL_NEAREST);
127         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
128                 GLES20.GL_TEXTURE_MAG_FILTER,
129                 GLES20.GL_LINEAR);
130 
131         GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
132                 GLES20.GL_REPEAT);
133         GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
134                 GLES20.GL_REPEAT);
135 
136         InputStream is = mContext.getResources()
137             .openRawResource(R.raw.robot);
138         Bitmap bitmap;
139         try {
140             bitmap = BitmapFactory.decodeStream(is);
141         } finally {
142             try {
143                 is.close();
144             } catch(IOException e) {
145                 // Ignore.
146             }
147         }
148 
149         GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
150         bitmap.recycle();
151 
152         Matrix.setLookAtM(mVMatrix, 0, 0, 0, -5, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
153     }
154 
loadShader(int shaderType, String source)155     private int loadShader(int shaderType, String source) {
156         int shader = GLES20.glCreateShader(shaderType);
157         if (shader != 0) {
158             GLES20.glShaderSource(shader, source);
159             GLES20.glCompileShader(shader);
160             int[] compiled = new int[1];
161             GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
162             if (compiled[0] == 0) {
163                 Log.e(TAG, "Could not compile shader " + shaderType + ":");
164                 Log.e(TAG, GLES20.glGetShaderInfoLog(shader));
165                 GLES20.glDeleteShader(shader);
166                 shader = 0;
167             }
168         }
169         return shader;
170     }
171 
createProgram(String vertexSource, String fragmentSource)172     private int createProgram(String vertexSource, String fragmentSource) {
173         int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
174         if (vertexShader == 0) {
175             return 0;
176         }
177 
178         int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
179         if (pixelShader == 0) {
180             return 0;
181         }
182 
183         int program = GLES20.glCreateProgram();
184         if (program != 0) {
185             GLES20.glAttachShader(program, vertexShader);
186             checkGlError("glAttachShader");
187             GLES20.glAttachShader(program, pixelShader);
188             checkGlError("glAttachShader");
189             GLES20.glLinkProgram(program);
190             int[] linkStatus = new int[1];
191             GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
192             if (linkStatus[0] != GLES20.GL_TRUE) {
193                 Log.e(TAG, "Could not link program: ");
194                 Log.e(TAG, GLES20.glGetProgramInfoLog(program));
195                 GLES20.glDeleteProgram(program);
196                 program = 0;
197             }
198         }
199         return program;
200     }
201 
checkGlError(String op)202     private void checkGlError(String op) {
203         int error;
204         while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
205             Log.e(TAG, op + ": glError " + error);
206             throw new RuntimeException(op + ": glError " + error);
207         }
208     }
209 
210     private static final int FLOAT_SIZE_BYTES = 4;
211     private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
212     private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
213     private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
214     private final float[] mTriangleVerticesData = {
215             // X, Y, Z, U, V
216             -1.0f, -0.5f, 0, -0.5f, 0.0f,
217             1.0f, -0.5f, 0, 1.5f, -0.0f,
218             0.0f,  1.11803399f, 0, 0.5f,  1.61803399f };
219 
220     private FloatBuffer mTriangleVertices;
221 
222     private final String mVertexShader =
223         "uniform mat4 uMVPMatrix;\n" +
224         "attribute vec4 aPosition;\n" +
225         "attribute vec2 aTextureCoord;\n" +
226         "varying vec2 vTextureCoord;\n" +
227         "void main() {\n" +
228         "  gl_Position = uMVPMatrix * aPosition;\n" +
229         "  vTextureCoord = aTextureCoord;\n" +
230         "}\n";
231 
232     private final String mFragmentShader =
233         "precision mediump float;\n" +
234         "varying vec2 vTextureCoord;\n" +
235         "uniform sampler2D sTexture;\n" +
236         "void main() {\n" +
237         "  gl_FragColor = texture2D(sTexture, vTextureCoord);\n" +
238         "}\n";
239 
240     private float[] mMVPMatrix = new float[16];
241     private float[] mProjMatrix = new float[16];
242     private float[] mMMatrix = new float[16];
243     private float[] mVMatrix = new float[16];
244 
245     private int mProgram;
246     private int mTextureID;
247     private int muMVPMatrixHandle;
248     private int maPositionHandle;
249     private int maTextureHandle;
250 
251     private Context mContext;
252     private static String TAG = "GLES20TriangleRenderer";
253 }
254