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diff --git a/docs/html/resources/tutorials/opengl/opengl-es10.jd b/docs/html/resources/tutorials/opengl/opengl-es10.jd
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@@ -1,532 +0,0 @@
-page.title=OpenGL ES 1.0
-parent.title=Tutorials
-parent.link=../../browser.html?tag=tutorial
-@jd:body
-
-
-<div id="qv-wrapper">
-  <div id="qv">
-    <h2>In this document</h2>
-    
-    <ol>
-      <li><a href="#creating">Create an Activity with GLSurfaceView</a></li>
-      <li>
-        <a href="#drawing">Draw a Shape on GLSurfaceView</a>
-        <ol>
-          <li><a href="#define-triangle">Define a Triangle</a></li>
-          <li><a href="#draw-triangle">Draw the Triangle</a></li>
-        </ol>
-      </li>
-      <li><a href="#projection-and-views">Apply Projection and Camera Views</a></li>
-      <li><a href="#motion">Add Motion</a></li>
-      <li><a href="#touch">Respond to Touch Events</a></li>
-    </ol>
-    <h2 id="code-samples-list">Related Samples</h2>
-    <ol>
-      <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-index.html">API Demos - graphics</a></li>
-      <li><a
-        href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-GLSurfaceViewActivity.html">OpenGL ES 1.0 Sample</a></li>
-      <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-TouchRotateActivity.html">TouchRotateActivity</a></li>
-    </ol>
-    <h2>See also</h2>
-    <ol>
-      <li><a href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a></li>
-      <li><a href="{@docRoot}resources/tutorials/opengl/opengl-es20.html">OpenGL
-ES 2.0</a></li>
-    </ol>
-    </div>
-  </div>
-
-<p>This tutorial shows you how to create a simple Android application that uses the OpenGL ES 1.0
-API to perform some basic graphics operations. You'll learn how to:</p>
-
-<ul>
-  <li>Create an activity using {@link android.opengl.GLSurfaceView} and {@link
-android.opengl.GLSurfaceView.Renderer}</li>
-  <li>Create and draw a graphic object</li>
-  <li>Define a projection to correct for screen geometry</li>
-  <li>Define a camera view</li>
-  <li>Rotate a graphic object</li>
-  <li>Make graphics touch-interactive</li>
-</ul>
-
-<p>The Android framework supports both the OpenGL ES 1.0/1.1 and OpenGL ES 2.0 APIs. You should
-carefully consider which version of the OpenGL ES API (1.0/1.1 or 2.0) is most appropriate for your
-needs. For more information, see
-<a href="{@docRoot}guide/topics/graphics/opengl.html#choosing-version">Choosing an OpenGL API
-Version</a>. If you would prefer to use OpenGL ES 2.0, see the <a
-href="{@docRoot}resources/tutorials/opengl/opengl-es20.html">OpenGL ES 2.0 tutorial</a>.</p>
-
-<p>Before you start, you should understand how to create a basic Android application. If you do not
-know how to create an app, follow the <a href="{@docRoot}resources/tutorials/hello-world.html">Hello
-World Tutorial</a> to familiarize yourself with the process.</p>
-
-<h2 id="creating">Create an Activity with GLSurfaceView</h2>
-
-<p>To get started using OpenGL, you must implement both a {@link android.opengl.GLSurfaceView} and a
-{@link android.opengl.GLSurfaceView.Renderer}. The {@link android.opengl.GLSurfaceView} is the main
-view type for applications that use OpenGL and the {@link android.opengl.GLSurfaceView.Renderer}
-controls what is drawn within that view. (For more information about these classes, see the <a
-href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a> document.)</p>
-
-<p>To create an activity using {@code GLSurfaceView}:</p>
-  
-<ol>
-  <li>Start a new Android project that targets Android 1.6 (API Level 4) or higher.
-  </li>
-  <li>Name the project <strong>HelloOpenGLES10</strong> and make sure it includes an activity called
-{@code HelloOpenGLES10}.
-  </li> 
-  <li>Modify the {@code HelloOpenGLES10} class as follows:
-<pre>
-package com.example.android.apis.graphics;
-
-import android.app.Activity;
-import android.content.Context;
-import android.opengl.GLSurfaceView;
-import android.os.Bundle;
-
-public class HelloOpenGLES10 extends Activity {
-  
-    private GLSurfaceView mGLView;
-  
-    &#64;Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        
-        // Create a GLSurfaceView instance and set it
-        // as the ContentView for this Activity.
-        mGLView = new HelloOpenGLES10SurfaceView(this);
-        setContentView(mGLView);
-    }
-    
-    &#64;Override
-    protected void onPause() {
-        super.onPause();
-        // The following call pauses the rendering thread.
-        // If your OpenGL application is memory intensive,
-        // you should consider de-allocating objects that
-        // consume significant memory here.
-        mGLView.onPause();
-    }
-    
-    &#64;Override
-    protected void onResume() {
-        super.onResume();
-        // The following call resumes a paused rendering thread.
-        // If you de-allocated graphic objects for onPause()
-        // this is a good place to re-allocate them.
-        mGLView.onResume();
-    }
-}
-  
-class HelloOpenGLES10SurfaceView extends GLSurfaceView {
-
-    public HelloOpenGLES10SurfaceView(Context context){
-        super(context);
-        
-        // Set the Renderer for drawing on the GLSurfaceView
-        setRenderer(new HelloOpenGLES10Renderer());
-    }
-}
-</pre>
-  <p class="note"><strong>Note:</strong> You will get a compile error for the {@code
-HelloOpenGLES10Renderer} class reference. That's expected; you will fix this error in the next step.
-  </p>
-  
-  <p>As shown above, this activity uses a single {@link android.opengl.GLSurfaceView} for its
-view. Notice that this activity implements crucial lifecycle callbacks for pausing and resuming its
-work.</p>
-
-  <p>The {@code HelloOpenGLES10SurfaceView} class in this example code above is just a thin wrapper
-for an instance of {@link android.opengl.GLSurfaceView} and is not strictly necessary for this
-example. However, if you want your application to monitor and respond to touch screen
-events&#8212;and we are guessing you do&#8212;you must extend {@link android.opengl.GLSurfaceView}
-to add touch event listeners, which you will learn how to do in the <a href="#touch">Reponding to
-Touch Events</a> section.</p>
-
-  <p>In order to draw graphics in the {@link android.opengl.GLSurfaceView}, you must define an
-implementation of {@link android.opengl.GLSurfaceView.Renderer}. In the next step, you create
-a renderer class to complete this OpenGL application.</p>
-  </li>
-
-  <li>Create a new file for the following class {@code HelloOpenGLES10Renderer}, which implements
-the {@link android.opengl.GLSurfaceView.Renderer} interface:
-
-<pre>
-package com.example.android.apis.graphics;
-
-import javax.microedition.khronos.egl.EGLConfig;
-import javax.microedition.khronos.opengles.GL10;
-
-import android.opengl.GLSurfaceView;
-
-public class HelloOpenGLES10Renderer implements GLSurfaceView.Renderer {
-
-    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
-        // Set the background frame color
-        gl.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
-    }
-    
-    public void onDrawFrame(GL10 gl) {
-        // Redraw background color
-        gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
-    }
-    
-    public void onSurfaceChanged(GL10 gl, int width, int height) {
-        gl.glViewport(0, 0, width, height);
-    }
-  
-}
-</pre>
-  <p>This minimal implementation of {@link android.opengl.GLSurfaceView.Renderer} provides the
-code structure needed to use OpenGL drawing methods:
-<ul>
-  <li>{@link
-    android.opengl.GLSurfaceView.Renderer#onSurfaceCreated(javax.microedition.khronos.opengles.GL10,
-    javax.microedition.khronos.egl.EGLConfig) onSurfaceCreated()} is called once to set up the
-{@link android.opengl.GLSurfaceView}
-environment.</li>
-  <li>{@link
-        android.opengl.GLSurfaceView.Renderer#onDrawFrame(javax.microedition.khronos.opengles.GL10)
-        onDrawFrame()} is called for each redraw of the {@link
-android.opengl.GLSurfaceView}.</li>
-  <li>{@link
-    android.opengl.GLSurfaceView.Renderer#onSurfaceChanged(javax.microedition.khronos.opengles.GL10,
-    int, int) onSurfaceChanged()} is called if the geometry of the {@link
-android.opengl.GLSurfaceView} changes, for example when the device's screen orientation
-changes.</li>
-</ul>
-  </p>
-  <p>For more information about these methods, see the <a
-href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a> document.
-</p>
-  </li>
-</ol>
-
-<p>The code example above creates a simple Android application that displays a grey screen using
-OpenGL ES 1.0 calls. While this application does not do anything very interesting, by creating these
-classes, you have layed the foundation needed to start drawing graphic elements with OpenGL ES
-1.0.</p>
-
-<p>If you are familiar with the OpenGL ES APIs, these classes should give you enough information
-to use the OpenGL ES 1.0 API and create graphics. However, if you need a bit more help getting
-started with OpenGL, head on to the next sections for a few more hints.</p>
-
-<h2 id="drawing">Draw a Shape on GLSurfaceView</h2>
-
-<p>Once you have implemented a {@link android.opengl.GLSurfaceView.Renderer}, the next step is to
-draw something with it. This section shows you how to define and draw a triangle.</p>
-
-<h3 id="define-triangle">Define a Triangle</h3>
-
-<p>OpenGL allows you to define objects using coordinates in three-dimensional space. So, before you
-  can draw a triangle, you must define its coordinates. In OpenGL, the typical way to do this is to
-  define a vertex array for the coordinates.</p>
-  
-<p>By default, OpenGL ES assumes a coordinate system where [0,0,0] (X,Y,Z) specifies the center of
-  the {@link android.opengl.GLSurfaceView} frame, [1,1,0] is the top right corner of the frame and 
-[-1,-1,0] is  bottom left corner of the frame.</p> 
-
-<p>To define a vertex array for a triangle:</p>
-
-<ol>
-  <li>In your {@code HelloOpenGLES10Renderer} class, add new member variable to contain the
-vertices of a triangle shape:
-<pre>
-    private FloatBuffer triangleVB;
-</pre>
-  </li>
-
-  <li>Create a method, {@code initShapes()} which populates this member variable:
-<pre>
-    private void initShapes(){
-    
-        float triangleCoords[] = {
-            // X, Y, Z
-            -0.5f, -0.25f, 0,
-             0.5f, -0.25f, 0,
-             0.0f,  0.559016994f, 0
-        }; 
-        
-        // initialize vertex Buffer for triangle  
-        ByteBuffer vbb = ByteBuffer.allocateDirect(
-                // (# of coordinate values * 4 bytes per float)
-                triangleCoords.length * 4); 
-        vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
-        triangleVB = vbb.asFloatBuffer();  // create a floating point buffer from the ByteBuffer
-        triangleVB.put(triangleCoords);    // add the coordinates to the FloatBuffer
-        triangleVB.position(0);            // set the buffer to read the first coordinate
-    
-    }
-</pre>
-    <p>This method defines a two-dimensional triangle with three equal sides.</p>
-  </li>
-  <li>Modify your {@code onSurfaceCreated()} method to initialize your triangle: 
-    <pre>
-    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
-    
-        // Set the background frame color
-        gl.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
-        
-        // initialize the triangle vertex array
-        initShapes();
-    }
-</pre>
-  <p class="caution"><strong>Caution:</strong> Shapes and other static objects should be initialized
-    once in your {@code onSurfaceCreated()} method for best performance. Avoid initializing the
-    new objects in {@code onDrawFrame()}, as this causes the system to re-create the objects
-    for every frame redraw and slows down your application.
-  </p>
-  </li>
-
-</ol>
-
-<p>You have now defined a triangle shape, but if you run the application, nothing appears. What?!
-You also have to tell OpenGL to draw the triangle, which you'll do in the next section.
-</p>
-
-
-<h3 id="draw-triangle">Draw the Triangle</h3>
-
-<p>Before you can draw your triangle, you must tell OpenGL that you are using vertex arrays. After
-that setup step, you can call the drawing APIs to display the triangle.</p>
-
-<p>To draw the triangle:</p>
-  
-<ol>
-  <li>Add the {@code glEnableClientState()} method to the end of {@code onSurfaceCreated()} to
-enable vertex arrays.
-<pre>
-        // Enable use of vertex arrays
-        gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
-</pre>
-    <p>At this point, you are ready to draw the triangle object in the OpenGL view.</p>
-  </li>
-  
-  <li>Add the following code to the end of your {@code onDrawFrame()} method to draw the triangle.
-<pre>
-        // Draw the triangle
-        gl.glColor4f(0.63671875f, 0.76953125f, 0.22265625f, 0.0f);
-        gl.glVertexPointer(3, GL10.GL_FLOAT, 0, triangleVB);
-        gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 3);
-</pre>
-  </li>
-  <li id="squashed-triangle">Run the app! Your application should look something like this:
-  </li>
-</ol>
-    
-<img src="{@docRoot}images/opengl/helloopengl-es10-1.png">
-<p class="img-caption">
-  <strong>Figure 1.</strong> Triangle drawn without a projection or camera view.
-</p>
-
-<p>There are a few problems with this example. First of all, it is not going to impress your
-friends. Secondly, the triangle is a bit squashed and changes shape when you change the screen
-orientation of the device. The reason the shape is skewed is due to the fact that the object is
-being rendered in a frame which is not perfectly square. You'll fix that problem using a projection
-and camera view in the next section.</p>
-
-<p>Lastly, because the triangle is stationary, the system is redrawing the object repeatedly in
-exactly the same place, which is not the most efficient use of the OpenGL graphics pipeline. In the
-<a href="#motion">Add Motion</a> section, you'll make this shape rotate and justify
-this use of processing power.</p>
-
-<h2 id="projection-and-views">Apply Projection and Camera View</h2>
-
-<p>One of the basic problems in displaying graphics is that Android device displays are typically
-not square and, by default, OpenGL happily maps a perfectly square, uniform coordinate
-system onto your typically non-square screen. To solve this problem, you can apply an OpenGL
-projection mode and camera view (eye point) to transform the coordinates of your graphic objects
-so they have the correct proportions on any display. For more information about OpenGL coordinate
-mapping, see <a href="{@docRoot}guide/topics/graphics/opengl.html#coordinate-mapping">Mapping
-Coordinates for Drawn Objects</a>.</p>
-
-<p>To apply projection and camera view transformations to your triangle:
-</p>
-<ol>
-  <li>Modify your {@code onSurfaceChanged()} method to enable {@link
-    javax.microedition.khronos.opengles.GL10#GL_PROJECTION GL10.GL_PROJECTION} mode, calculate the
-    screen ratio and apply the ratio as a transformation of the object coordinates.
-<pre>
-  public void onSurfaceChanged(GL10 gl, int width, int height) {
-      gl.glViewport(0, 0, width, height);
-      
-      // make adjustments for screen ratio
-      float ratio = (float) width / height;
-      gl.glMatrixMode(GL10.GL_PROJECTION);        // set matrix to projection mode
-      gl.glLoadIdentity();                        // reset the matrix to its default state
-      gl.glFrustumf(-ratio, ratio, -1, 1, 3, 7);  // apply the projection matrix
-  }  
-</pre>
-  </li>
-
-  <li>Next, modify your {@code onDrawFrame()} method to apply the {@link
-javax.microedition.khronos.opengles.GL10#GL_MODELVIEW GL_MODELVIEW} mode and set
-a view point using {@link android.opengl.GLU#gluLookAt(javax.microedition.khronos.opengles.GL10,
-float, float, float, float, float, float, float, float, float) GLU.gluLookAt()}.
-<pre>
-    public void onDrawFrame(GL10 gl) {
-        // Redraw background color
-        gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
-        
-        // Set GL_MODELVIEW transformation mode
-        gl.glMatrixMode(GL10.GL_MODELVIEW);
-        gl.glLoadIdentity();   // reset the matrix to its default state
-        
-        // When using GL_MODELVIEW, you must set the view point
-        GLU.gluLookAt(gl, 0, 0, -5, 0f, 0f, 0f, 0f, 1.0f, 0.0f);        
-        
-        // Draw the triangle
-        ...
-    }
-</pre>
-  </li>
-  <li>Run the updated application and you should see something like this:</li>
-</ol>
-
-<img src="{@docRoot}images/opengl/helloopengl-es10-2.png">
-<p class="img-caption">
-  <strong>Figure 2.</strong> Triangle drawn with a projection and camera view applied.
-</p>
-
-<p>Now that you have applied this transformation, the triangle has three equal sides, instead of the
-<a href="#squashed-triangle">squashed triangle</a> in the earlier version.</p>
-
-<h2 id="motion">Add Motion</h2>
-
-<p>While it may be an interesting exercise to create static graphic objects with OpenGL ES, chances
-are you want at least <em>some</em> of your objects to move. In this section, you'll add motion to
-your triangle by rotating it.</p>
-
-<p>To add rotation to your triangle:</p>
-<ol>
-  <li>Modify your {@code onDrawFrame()} method to rotate the triangle object:
-<pre>
-    public void onDrawFrame(GL10 gl) {
-        ...    
-        // When using GL_MODELVIEW, you must set the view point
-        GLU.gluLookAt(gl, 0, 0, -5, 0f, 0f, 0f, 0f, 1.0f, 0.0f);        
-    
-        // Create a rotation for the triangle
-        long time = SystemClock.uptimeMillis() % 4000L;
-        float angle = 0.090f * ((int) time);
-        gl.glRotatef(angle, 0.0f, 0.0f, 1.0f);        
-        
-        // Draw the triangle
-        ...
-    }
-</pre>
-  </li>
-  <li>Run the application and your triangle should rotate around its center.</li>
-</ol>
-
-
-<h2 id="touch">Respond to Touch Events</h2>
-<p>Making objects move according to a preset program like the rotating triangle  is useful for
-getting some attention, but what if you want to have users interact with your OpenGL graphics? In
-this section, you'll learn how listen for touch events to let users interact with objects in your
-{@code HelloOpenGLES10SurfaceView}.</p>
-  
-<p>The key to making your OpenGL application touch interactive is expanding your implementation of
-{@link android.opengl.GLSurfaceView} to override the {@link 
-android.view.View#onTouchEvent(android.view.MotionEvent) onTouchEvent()} to listen for touch events.
-Before you do that, however, you'll modify the renderer class to expose the rotation angle of the
-triangle. Afterwards, you'll modify the {@code HelloOpenGLES10SurfaceView} to process touch events
-and pass that data to your renderer.</p>
-
-<p>To make your triangle rotate in response to touch events:</p>
-
-<ol>
-  <li>Modify your {@code HelloOpenGLES10Renderer} class to include a new, public member so that
-your {@code HelloOpenGLES10SurfaceView} class is able to pass new rotation values your renderer:
-<pre>
-    public float mAngle;
-</pre>  
-  </li>
-  <li>In your {@code onDrawFrame()} method, comment out the code that generates an angle and
-replace the {@code angle} variable with {@code mAngle}.
-<pre>
-        // Create a rotation for the triangle (Boring! Comment this out:)
-        // long time = SystemClock.uptimeMillis() % 4000L;
-        // float angle = 0.090f * ((int) time);
-
-        // Use the mAngle member as the rotation value
-        gl.glRotatef(mAngle, 0.0f, 0.0f, 1.0f); 
-</pre>
-  </li>
-  <li>In your {@code HelloOpenGLES10SurfaceView} class, add the following member variables.
-<pre>
-    private final float TOUCH_SCALE_FACTOR = 180.0f / 320;
-    private HelloOpenGLES10Renderer mRenderer;
-    private float mPreviousX;
-    private float mPreviousY;
-</pre>
-  </li>
-  <li>In the constructor method for {@code HelloOpenGLES10SurfaceView}, set the {@code mRenderer}
-member so you have a handle to pass in rotation input and set the render mode to {@link
-android.opengl.GLSurfaceView#RENDERMODE_WHEN_DIRTY}.
-<pre>
-    public HelloOpenGLES10SurfaceView(Context context){
-        super(context);
-        // set the mRenderer member
-        mRenderer = new HelloOpenGLES10Renderer();
-        setRenderer(mRenderer);
-        
-        // Render the view only when there is a change
-        setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
-    }
-</pre>
-  </li>
-  <li>In your {@code HelloOpenGLES10SurfaceView} class, override the {@link
-android.view.View#onTouchEvent(android.view.MotionEvent) onTouchEvent()} method to listen for touch
-events and pass them to your renderer.
-<pre>
-    &#64;Override 
-    public boolean onTouchEvent(MotionEvent e) {
-        // MotionEvent reports input details from the touch screen
-        // and other input controls. In this case, you are only
-        // interested in events where the touch position changed.
-
-        float x = e.getX();
-        float y = e.getY();
-        
-        switch (e.getAction()) {
-            case MotionEvent.ACTION_MOVE:
-    
-                float dx = x - mPreviousX;
-                float dy = y - mPreviousY;
-    
-                // reverse direction of rotation above the mid-line
-                if (y &gt; getHeight() / 2) {
-                  dx = dx * -1 ;
-                }
-    
-                // reverse direction of rotation to left of the mid-line
-                if (x &lt; getWidth() / 2) {
-                  dy = dy * -1 ;
-                }
-              
-                mRenderer.mAngle += (dx + dy) * TOUCH_SCALE_FACTOR;
-                requestRender();
-        }
-
-        mPreviousX = x;
-        mPreviousY = y;
-        return true;
-    } 
-</pre>
-  <p class="note"><strong>Note:</strong> Touch events return pixel coordinates which <em>are not the
-same</em> as OpenGL coordinates. Touch coordinate [0,0] is the bottom-left of the screen and the
-highest value [max_X, max_Y] is the top-right corner of the screen. To match touch events to OpenGL
-graphic objects, you must translate touch coordinates into OpenGL coordinates.</p>
-  </li>
-  <li>Run the application and drag your finger or cursor around the screen to rotate the
-triangle.</li>
-</ol>
-<p>For another example of OpenGL touch event functionality, see <a
-href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-TouchRotateActivity.html">TouchRotateActivity</a>.</p>
\ No newline at end of file
diff --git a/docs/html/resources/tutorials/opengl/opengl-es20.jd b/docs/html/resources/tutorials/opengl/opengl-es20.jd
deleted file mode 100644
index dd23dbf..0000000
--- a/docs/html/resources/tutorials/opengl/opengl-es20.jd
+++ /dev/null
@@ -1,652 +0,0 @@
-page.title=OpenGL ES 2.0
-parent.title=Tutorials
-parent.link=../../browser.html?tag=tutorial
-@jd:body
-
-
-<div id="qv-wrapper">
-  <div id="qv">
-    <h2>In this document</h2>
-    
-    <ol>
-      <li><a href="#creating">Create an Activity with GLSurfaceView</a></li>
-      <li>
-        <a href="#drawing">Draw a Shape on GLSurfaceView</a>
-        <ol>
-          <li><a href="#define-triangle">Define a Triangle</a></li>
-          <li><a href="#draw-triangle">Draw the Triangle</a></li>
-        </ol>
-      </li>
-      <li><a href="#projection-and-views">Apply Projection and Camera Views</a></li>
-      <li><a href="#motion">Add Motion</a></li>
-      <li><a href="#touch">Respond to Touch Events</a></li>
-    </ol>
-    <h2 id="code-samples-list">Related Samples</h2>
-    <ol>
-      <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-index.html">API Demos - graphics</a></li>
-      <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-GLES20Activity.html">OpenGL ES 2.0 Sample</a></li>
-      <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-TouchRotateActivity.html">TouchRotateActivity</a></li>
-    </ol>
-    <h2>See also</h2>
-    <ol>
-      <li><a href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a></li>
-      <li><a href="{@docRoot}resources/tutorials/opengl/opengl-es10.html">OpenGL
-ES 1.0</a></li>
-    </ol>
-    </div>
-  </div>
-
-<p>This tutorial shows you how to create a simple Android application that uses the OpenGL ES 2.0
-API to perform some basic graphics operations. You'll learn how to:</p>
-
-<ul>
-  <li>Create an activity using {@link android.opengl.GLSurfaceView} and {@link
-android.opengl.GLSurfaceView.Renderer}</li>
-  <li>Create and draw a graphic object</li>
-  <li>Define a projection to correct for screen geometry</li>
-  <li>Define a camera view</li>
-  <li>Rotate a graphic object</li>
-  <li>Make graphics touch interactive</li>
-</ul>
-
-<p>The Android framework supports both the OpenGL ES 1.0/1.1 and OpenGL ES 2.0 APIs. You should
-carefully consider which version of the OpenGL ES API (1.0/1.1 or 2.0) is most appropriate for your
-needs. For more information, see
-<a href="{@docRoot}guide/topics/graphics/opengl.html#choosing-version">Choosing an OpenGL API
-Version</a>. If you would prefer to use OpenGL ES 1.0, see the <a
-href="{@docRoot}resources/tutorials/opengl/opengl-es10.html">OpenGL ES 1.0 tutorial</a>.</p>
-
-<p>Before you start, you should understand how to create a basic Android application. If you do not
-know how to create an app, follow the <a href="{@docRoot}resources/tutorials/hello-world.html">Hello
-World Tutorial</a> to familiarize yourself with the process.</p>
-
-<p class="caution"><strong>Caution:</strong> OpenGL ES 2.0 <em>is currently not supported</em> by
-the Android Emulator. You must have a physical test device running Android 2.2 (API Level 8) or
-higher in order to run and test the example code in this tutorial.</p>
-
-<h2 id="creating">Create an Activity with GLSurfaceView</h2>
-
-<p>To get started using OpenGL, you must implement both a {@link android.opengl.GLSurfaceView} and a
-{@link android.opengl.GLSurfaceView.Renderer}. The {@link android.opengl.GLSurfaceView} is the main
-view type for applications that use OpenGL and the {@link android.opengl.GLSurfaceView.Renderer}
-controls what is drawn within that view. (For more information about these classes, see the <a
-href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a> document.)</p>
-
-<p>To create an activity using {@code GLSurfaceView}:</p>
-  
-<ol>
-  <li>Start a new Android project that targets Android 2.2 (API Level 8) or higher.
-  </li>
-  <li>Name the project <strong>HelloOpenGLES20</strong> and make sure it includes an activity called
-{@code HelloOpenGLES20}.
-  </li> 
-  <li>Modify the {@code HelloOpenGLES20} class as follows:
-<pre>
-package com.example.android.apis.graphics;
-
-import android.app.Activity;
-import android.content.Context;
-import android.opengl.GLSurfaceView;
-import android.os.Bundle;
-
-public class HelloOpenGLES20 extends Activity {
-  
-    private GLSurfaceView mGLView;
-  
-    &#64;Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        
-        // Create a GLSurfaceView instance and set it
-        // as the ContentView for this Activity
-        mGLView = new HelloOpenGLES20SurfaceView(this);
-        setContentView(mGLView);
-    }
-    
-    &#64;Override
-    protected void onPause() {
-        super.onPause();
-        // The following call pauses the rendering thread.
-        // If your OpenGL application is memory intensive,
-        // you should consider de-allocating objects that
-        // consume significant memory here.
-        mGLView.onPause();
-    }
-    
-    &#64;Override
-    protected void onResume() {
-        super.onResume();
-        // The following call resumes a paused rendering thread.
-        // If you de-allocated graphic objects for onPause()
-        // this is a good place to re-allocate them.
-        mGLView.onResume();
-    }
-}
-  
-class HelloOpenGLES20SurfaceView extends GLSurfaceView {
-
-    public HelloOpenGLES20SurfaceView(Context context){
-        super(context);
-        
-        // Create an OpenGL ES 2.0 context.
-        setEGLContextClientVersion(2);
-        // Set the Renderer for drawing on the GLSurfaceView
-        setRenderer(new HelloOpenGLES20Renderer());
-    }
-}
-</pre>
-  <p class="note"><strong>Note:</strong> You will get a compile error for the {@code
-HelloOpenGLES20Renderer} class reference. That's expected; you will fix this error in the next step.
-  </p>
-  
-  <p>As shown above, this activity uses a single {@link android.opengl.GLSurfaceView} for its
-view. Notice that this activity implements crucial lifecycle callbacks for pausing and resuming its
-work.</p>
-
-  <p>The {@code HelloOpenGLES20SurfaceView} class in this example code above is just a thin wrapper
-for an instance of {@link android.opengl.GLSurfaceView} and is not strictly necessary for this
-example. However, if you want your application to monitor and respond to touch screen
-events&#8212;and we are guessing you do&#8212;you must extend {@link android.opengl.GLSurfaceView}
-to add touch event listeners, which you will learn how to do in the <a href="#touch">Reponding to
-Touch Events</a> section.</p>
-
-  <p>In order to draw graphics in the {@link android.opengl.GLSurfaceView}, you must define an
-implementation of {@link android.opengl.GLSurfaceView.Renderer}. In the next step, you create
-a renderer class to complete this OpenGL application.</p>
-  </li>
-
-  <li>Create a new file for the following class {@code HelloOpenGLES20Renderer}, which implements
-the {@link android.opengl.GLSurfaceView.Renderer} interface:
-
-<pre>
-package com.example.android.apis.graphics;
-
-import javax.microedition.khronos.egl.EGLConfig;
-import javax.microedition.khronos.opengles.GL10;
-
-import android.opengl.GLES20;
-import android.opengl.GLSurfaceView;
-
-public class HelloOpenGLES20Renderer implements GLSurfaceView.Renderer {
-  
-    public void onSurfaceCreated(GL10 unused, EGLConfig config) {
-    
-        // Set the background frame color
-        GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
-    }
-    
-    public void onDrawFrame(GL10 unused) {
-    
-        // Redraw background color
-        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
-    }
-    
-    public void onSurfaceChanged(GL10 unused, int width, int height) {
-        GLES20.glViewport(0, 0, width, height);
-    }
-  
-}
-</pre>
-  <p>This minimal implementation of {@link android.opengl.GLSurfaceView.Renderer} provides the
-code structure needed to use OpenGL drawing methods:
-<ul>
-  <li>{@link
-    android.opengl.GLSurfaceView.Renderer#onSurfaceCreated(javax.microedition.khronos.opengles.GL10,
-    javax.microedition.khronos.egl.EGLConfig) onSurfaceCreated()} is called once to set up the
-{@link android.opengl.GLSurfaceView}
-environment.</li>
-  <li>{@link
-        android.opengl.GLSurfaceView.Renderer#onDrawFrame(javax.microedition.khronos.opengles.GL10)
-        onDrawFrame()} is called for each redraw of the {@link
-android.opengl.GLSurfaceView}.</li>
-  <li>{@link
-    android.opengl.GLSurfaceView.Renderer#onSurfaceChanged(javax.microedition.khronos.opengles.GL10,
-    int, int) onSurfaceChanged()} is called if the geometry of the {@link
-android.opengl.GLSurfaceView} changes, for example when the device's screen orientation
-changes.</li>
-</ul>
-  </p>
-  <p>For more information about these methods, see the <a
-href="{@docRoot}guide/topics/graphics/opengl.html">3D with OpenGL</a> document.
-</p>
-  </li>
-</ol>
-
-<p>The code example above creates a simple Android application that displays a grey screen using
-OpenGL ES 2.0 calls. While this application does not do anything very interesting, by creating these
-classes, you have layed the foundation needed to start drawing graphic elements with OpenGL ES
-2.0.</p>
-
-<p>If you are familiar with the OpenGL ES APIs, these classes should give you enough information
-to use the OpenGL ES 2.0 API and create graphics. However, if you need a bit more help getting
-started with OpenGL, head on to the next sections for a few more hints.</p>
-
-<p class="note"><strong>Note:</strong> If your application requires OpenGL 2.0, make sure you
-declare this in your manifest:</p>
-<pre>
-    &lt;!-- Tell the system this app requires OpenGL ES 2.0. --&gt;
-    &lt;uses-feature android:glEsVersion="0x00020000" android:required="true" /&gt;
-</pre>
-<p>For more information, see <a
-href="{@docRoot}guide/topics/graphics/opengl.html#manifest">OpenGL manifest declarations</a> in the
-<em>3D with OpenGL</em> document.</p>
-
-
-<h2 id="drawing">Draw a Shape on GLSurfaceView</h2>
-
-<p>Once you have implemented a {@link android.opengl.GLSurfaceView.Renderer}, the next step is to
-draw something with it. This section shows you how to define and draw a triangle.</p>
-
-<h3 id="define-triangle">Define a Triangle</h3>
-
-<p>OpenGL allows you to define objects using coordinates in three-dimensional space. So, before you
-  can draw a triangle, you must define its coordinates. In OpenGL, the typical way to do this is to
-  define a vertex array for the coordinates.</p>
-  
-<p>By default, OpenGL ES assumes a coordinate system where [0,0,0] (X,Y,Z) specifies the center of
-  the {@link android.opengl.GLSurfaceView} frame, [1,1,0] is the top-right corner of the frame and 
-[-1,-1,0] is  bottom-left corner of the frame.</p> 
-
-<p>To define a vertex array for a triangle:</p>
-
-<ol>
-  <li>In your {@code HelloOpenGLES20Renderer} class, add new member variable to contain the
-vertices of a triangle shape:
-<pre>
-    private FloatBuffer triangleVB;
-</pre>
-  </li>
-
-  <li>Create a method, {@code initShapes()} which populates this member variable:
-<pre>
-    private void initShapes(){
-    
-        float triangleCoords[] = {
-            // X, Y, Z
-            -0.5f, -0.25f, 0,
-             0.5f, -0.25f, 0,
-             0.0f,  0.559016994f, 0
-        }; 
-        
-        // initialize vertex Buffer for triangle  
-        ByteBuffer vbb = ByteBuffer.allocateDirect(
-                // (# of coordinate values * 4 bytes per float)
-                triangleCoords.length * 4); 
-        vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
-        triangleVB = vbb.asFloatBuffer();  // create a floating point buffer from the ByteBuffer
-        triangleVB.put(triangleCoords);    // add the coordinates to the FloatBuffer
-        triangleVB.position(0);            // set the buffer to read the first coordinate
-    
-    }
-</pre>
-    <p>This method defines a two-dimensional triangle shape with three equal sides.</p>
-  </li>
-  <li>Modify your {@code onSurfaceCreated()} method to initialize your triangle:
-<pre>
-    public void onSurfaceCreated(GL10 unused, EGLConfig config) {
-    
-        // Set the background frame color
-        GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
-        
-        // initialize the triangle vertex array
-        initShapes();
-    }
-</pre>
-  <p class="caution"><strong>Caution:</strong> Shapes and other static objects should be initialized
-    once in your {@code onSurfaceCreated()} method for best performance. Avoid initializing the
-    new objects in {@code onDrawFrame()}, as this causes the system to re-create the objects
-    for every frame redraw and slows down your application.
-  </p>
-  </li>
-
-</ol>
-
-<p>You have now defined a triangle shape, but if you run the application, nothing appears. What?!
-You also have to tell OpenGL to draw the triangle, which you'll do in the next section.
-</p>
-
-
-<h3 id="draw-triangle">Draw the Triangle</h3>
-
-<p>The OpenGL ES 2.0 requires a bit more code than OpenGL ES 1.0/1.1 in order to draw objects. In
-this section, you'll create vertex and fragment shaders, a shader loader, apply the shaders, enable
-the use of vertex arrays for your triangle and, finally, draw it on screen.</p>
-
-<p>To draw the triangle:</p>
-  
-<ol>
-  <li>In your {@code HelloOpenGLES20Renderer} class, define a vertex shader and a fragment
-shader. Shader code is defined as a string which is compiled and run by the OpenGL ES 2.0 rendering
-engine.
-<pre>
-    private final String vertexShaderCode = 
-        "attribute vec4 vPosition; \n" +
-        "void main(){              \n" +
-        " gl_Position = vPosition; \n" +
-        "}                         \n";
-    
-    private final String fragmentShaderCode = 
-        "precision mediump float;  \n" +
-        "void main(){              \n" +
-        " gl_FragColor = vec4 (0.63671875, 0.76953125, 0.22265625, 1.0); \n" +
-        "}                         \n";
-</pre>
-    <p>The vertex shader controls how OpenGL positions and draws the vertices of shapes in space.
-The fragment shader controls what OpenGL draws <em>between</em> the vertices of shapes.</p>
-  </li>
-  <li>In your {@code HelloOpenGLES20Renderer} class, create a method for loading the shaders.
-<pre>
-    private int loadShader(int type, String shaderCode){
-    
-        // create a vertex shader type (GLES20.GL_VERTEX_SHADER)
-        // or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
-        int shader = GLES20.glCreateShader(type); 
-        
-        // add the source code to the shader and compile it
-        GLES20.glShaderSource(shader, shaderCode);
-        GLES20.glCompileShader(shader);
-        
-        return shader;
-    }
-</pre>
-  </li>
-  
-  <li>Add the following members to your {@code HelloOpenGLES20Renderer} class for an OpenGL
-Program and the positioning control for your triangle.
-<pre>
-    private int mProgram;
-    private int maPositionHandle;
-</pre>
-    <p>In OpenGL ES 2.0, you attach vertex and fragment shaders to a <em>Program</em> and then
-apply the program to the OpenGL graphics pipeline.</p>
-  </li>
-  
-  <li>Add the following code to the end of your {@code onSurfaceCreated()} method to load the
-shaders and attach them to an OpenGL Program.
-<pre>
-        int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
-        int fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
-        
-        mProgram = GLES20.glCreateProgram();             // create empty OpenGL Program
-        GLES20.glAttachShader(mProgram, vertexShader);   // add the vertex shader to program
-        GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
-        GLES20.glLinkProgram(mProgram);                  // creates OpenGL program executables
-        
-        // get handle to the vertex shader's vPosition member
-        maPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
-</pre>
-    <p>At this point, you are ready to draw the triangle object in the OpenGL view.</p>
-  </li>
-  
-  <li>Add the following code to the end of your {@code onDrawFrame()} method apply the OpenGL
-program you created, load the triangle object and draw the triangle.
-<pre>
-        // Add program to OpenGL environment
-        GLES20.glUseProgram(mProgram);
-        
-        // Prepare the triangle data
-        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false, 12, triangleVB);
-        GLES20.glEnableVertexAttribArray(maPositionHandle);
-        
-        // Draw the triangle
-        GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 3);
-</pre>
-  </li>
-  <li id="squashed-triangle">Run the app! Your application should look something like this:
-  </li>
-</ol>
-
-<img src="{@docRoot}images/opengl/helloopengl-es20-1.png">
-<p class="img-caption">
-  <strong>Figure 1.</strong> Triangle drawn without a projection or camera view.
-</p>
-
-<p>There are a few problems with this example. First of all, it is not going to impress your
-friends. Secondly, the triangle is a bit squashed and changes shape when you change the screen
-orientation of the device. The reason the shape is skewed is due to the fact that the object is
-being rendered in a frame which is not perfectly square. You'll fix that problem using a projection
-and camera view in the next section.</p>
-
-<p>Lastly, because the triangle is stationary, the system is redrawing the object repeatedly in
-exactly the same place, which is not the most efficient use of the OpenGL graphics pipeline. In the
-<a href="#motion">Add Motion</a> section, you'll make this shape rotate and justify
-this use of processing power.</p>
-
-<h2 id="projection-and-views">Apply Projection and Camera View</h2>
-
-<p>One of the basic problems in displaying graphics is that Android device displays are typically
-not square and, by default, OpenGL happily maps a perfectly square, uniform coordinate
-system onto your typically non-square screen. To solve this problem, you can apply an OpenGL
-projection mode and camera view (eye point) to transform the coordinates of your graphic objects
-so they have the correct proportions on any display. For more information about OpenGL coordinate
-mapping, see <a href="{@docRoot}guide/topics/graphics/opengl.html#coordinate-mapping">Mapping
-Coordinates for Drawn Objects</a>.</p>
-
-<p>To apply projection and camera view transformations to your triangle:
-</p>
-<ol>
-  <li>Add the following members to your {@code HelloOpenGLES20Renderer} class.
-<pre>
-    private int muMVPMatrixHandle;
-    private float[] mMVPMatrix = new float[16];
-    private float[] mMMatrix = new float[16];
-    private float[] mVMatrix = new float[16];
-    private float[] mProjMatrix = new float[16];
-</pre>
-    </li>
-    <li>Modify your {@code vertexShaderCode} string to add a variable for a model view
-projection matrix.
-<pre>
-    private final String vertexShaderCode = 
-        // This matrix member variable provides a hook to manipulate
-        // the coordinates of the objects that use this vertex shader
-        "uniform mat4 uMVPMatrix;   \n" +
-        
-        "attribute vec4 vPosition;  \n" +
-        "void main(){               \n" +
-        
-        // the matrix must be included as a modifier of gl_Position
-        " gl_Position = uMVPMatrix * vPosition; \n" +
-        
-        "}  \n";
-</pre>
-    </li>
-    <li>Modify the {@code onSurfaceChanged()} method to calculate the device screen ratio and
-create a projection matrix.
-<pre>
-    public void onSurfaceChanged(GL10 unused, int width, int height) {
-        GLES20.glViewport(0, 0, width, height);
-        
-        float ratio = (float) width / height;
-        
-        // this projection matrix is applied to object coodinates
-        // in the onDrawFrame() method
-        Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
-    }  
-</pre>
-    </li>
-    <li>Add the following code to the end of your {@code onSurfaceChanged()} method to
-reference the {@code uMVPMatrix} shader matrix variable you added in step 2.
-<pre>
-        muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
-</pre>
-    </li>
-    <li>Add the following code to the end of your {@code onSurfaceChanged()} method to define
-a camera view matrix.
-<pre>
-        Matrix.setLookAtM(mVMatrix, 0, 0, 0, -3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
-</pre>
-    </li>
-    <li>Finally, modify your {@code onDrawFrame()} method to combine the projection and
-camera view matrices and then apply the combined transformation to the OpenGL rendering pipeline.
-<pre>
-    public void onDrawFrame(GL10 unused) {
-        ...
-        // Apply a ModelView Projection transformation
-        Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mVMatrix, 0);
-        GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
-        
-        // Draw the triangle
-        ...
-    }
-</pre>
-  </li>
-  <li>Run the updated application and you should see something like this:</li>
-</ol>
-
-<img src="{@docRoot}images/opengl/helloopengl-es20-2.png">
-<p class="img-caption">
-  <strong>Figure 2.</strong> Triangle drawn with a projection and camera view applied.
-</p>
-
-<p>Now that you have applied this transformation, the triangle has three equal sides, instead of the
-<a href="#squashed-triangle">squashed triangle</a> in the earlier version.</p>
-
-<h2 id="motion">Add Motion</h2>
-
-<p>While it may be an interesting exercise to create static graphic objects with OpenGL ES, chances
-are you want at least <em>some</em> of your objects to move. In this section, you'll add motion to
-your triangle by rotating it.</p>
-
-<p>To add rotation to your triangle:</p>
-<ol>
-  <li>Add an additional tranformation matrix member to your {@code HelloOpenGLES20Renderer}
-class.
-    <pre>
-      private float[] mMMatrix = new float[16];
-    </pre>
-    </li>
-  <li>Modify your {@code onDrawFrame()} method to rotate the triangle object.
-<pre>
-    public void onDrawFrame(GL10 gl) {
-        ...
-    
-        // Create a rotation for the triangle
-        long time = SystemClock.uptimeMillis() % 4000L;
-        float angle = 0.090f * ((int) time);
-        Matrix.setRotateM(mMMatrix, 0, angle, 0, 0, 1.0f);
-        Matrix.multiplyMM(mMVPMatrix, 0, mVMatrix, 0, mMMatrix, 0);
-        Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mMVPMatrix, 0);
-        
-        // Apply a ModelView Projection transformation
-        GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
-        
-        // Draw the triangle
-        ...
-    }
-</pre>
-  </li>
-  <li>Run the application and your triangle should rotate around its center.</li>
-</ol>
-
-
-<h2 id="touch">Respond to Touch Events</h2>
-<p>Making objects move according to a preset program like the rotating triangle  is useful for
-getting some attention, but what if you want to have users interact with your OpenGL graphics? In
-this section, you'll learn how listen for touch events to let users interact with objects in your
-{@code HelloOpenGLES20SurfaceView}.</p>
-  
-<p>The key to making your OpenGL application touch interactive is expanding your implementation of
-{@link android.opengl.GLSurfaceView} to override the {@link 
-android.view.View#onTouchEvent(android.view.MotionEvent) onTouchEvent()} to listen for touch events.
-Before you do that, however, you'll modify the renderer class to expose the rotation angle of the
-triangle. Afterwards, you'll modify the {@code HelloOpenGLES20SurfaceView} to process touch events
-and pass that data to your renderer.</p>
-
-<p>To make your triangle rotate in response to touch events:</p>
-
-<ol>
-  <li>Modify your {@code HelloOpenGLES20Renderer} class to include a new, public member so that
-your {@code HelloOpenGLES10SurfaceView} class is able to pass new rotation values your renderer:
-<pre>
-    public float mAngle;
-</pre>  
-  </li>
-  <li>In your {@code onDrawFrame()} method, comment out the code that generates an angle and
-replace the {@code angle} variable with {@code mAngle}.
-<pre>
-        // Create a rotation for the triangle (Boring! Comment this out:)
-        // long time = SystemClock.uptimeMillis() % 4000L;
-        // float angle = 0.090f * ((int) time);
-
-        // Use the mAngle member as the rotation value
-        Matrix.setRotateM(mMMatrix, 0, mAngle, 0, 0, 1.0f);
-</pre>
-  </li>
-  <li>In your {@code HelloOpenGLES20SurfaceView} class, add the following member variables.
-<pre>
-    private final float TOUCH_SCALE_FACTOR = 180.0f / 320;
-    private HelloOpenGLES20Renderer mRenderer;
-    private float mPreviousX;
-    private float mPreviousY;
-</pre>
-  </li>
-  <li>In the constructor method for {@code HelloOpenGLES20SurfaceView}, set the {@code mRenderer}
-member so you have a handle to pass in rotation input and set the render mode to {@link
-android.opengl.GLSurfaceView#RENDERMODE_WHEN_DIRTY}.<pre>
-    public HelloOpenGLES20SurfaceView(Context context){
-        super(context);
-        // Create an OpenGL ES 2.0 context.
-        setEGLContextClientVersion(2);
-            
-        // set the mRenderer member
-        mRenderer = new HelloOpenGLES20Renderer();
-        setRenderer(mRenderer);
-        
-        // Render the view only when there is a change
-        setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
-    }
-</pre>
-  </li>
-  <li>In your {@code HelloOpenGLES20SurfaceView} class, override the {@link
-android.view.View#onTouchEvent(android.view.MotionEvent) onTouchEvent()} method to listen for touch
-events and pass them to your renderer.
-<pre>
-    &#64;Override 
-    public boolean onTouchEvent(MotionEvent e) {
-        // MotionEvent reports input details from the touch screen
-        // and other input controls. In this case, you are only
-        // interested in events where the touch position changed.
-
-        float x = e.getX();
-        float y = e.getY();
-        
-        switch (e.getAction()) {
-            case MotionEvent.ACTION_MOVE:
-    
-                float dx = x - mPreviousX;
-                float dy = y - mPreviousY;
-    
-                // reverse direction of rotation above the mid-line
-                if (y &gt; getHeight() / 2) {
-                  dx = dx * -1 ;
-                }
-    
-                // reverse direction of rotation to left of the mid-line
-                if (x &lt; getWidth() / 2) {
-                  dy = dy * -1 ;
-                }
-              
-                mRenderer.mAngle += (dx + dy) * TOUCH_SCALE_FACTOR;
-                requestRender();
-        }
-
-        mPreviousX = x;
-        mPreviousY = y;
-        return true;
-    } 
-</pre>
-  <p class="note"><strong>Note:</strong> Touch events return pixel coordinates which <em>are not the
-same</em> as OpenGL coordinates. Touch coordinate [0,0] is the bottom-left of the screen and the
-highest value [max_X, max_Y] is the top-right corner of the screen. To match touch events to OpenGL
-graphic objects, you must translate touch coordinates into OpenGL coordinates.</p>
-  </li>
-  <li>Run the application and drag your finger or cursor around the screen to rotate the
-triangle.</li>
-</ol>
-<p>For another example of OpenGL touch event functionality, see <a
-href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/graphics/
-TouchRotateActivity.html">TouchRotateActivity</a>.</p>
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