Tutorial on Android OpenGL

OpenGL on Android-powered devices allow the rendering of 3D graphics.

OpenGL is a standard specification API that is used to produce 3D graphics. Android OpenGL works using the same theory to render 3D graphics on the Android platform. In addition to the Google Code that addresses how to use the Android OpenGL, there are hundreds of developers working on the OpenGL platform and their code samples can be used by any beginner to get started in using this open standard for their Android applications.

Instructions

Set Up

1. Set up the GLSurfaceView by calling the function below:

   Public void setRenderer (GLSurfaceView.Renderer renderer)

2. Implement the functions below inside the renderer:

   Public void onSurfaceCreated (GL10 gl, EGLConfig config)

   Public void on DrawFrame (GL10, gl)

   Public void onSufaceChanged (GL10 gl, width, int height)

3. Create an activity by importing the necessary files and classes using the "import android" function. Specify the renderer elements such as the "onSurfaceCreated" color, model and depth. Do the same for "onSurfaceChanged" function.

3D Example

1. Create a new project called "3D" and a new class by the same name as shown below:

   Import android.cotent.Context;

   Import android.opengl.GLSurfaceView;

   Public class 3DView extends GLSurfaceView {

   Private

   Public 3DView 9Context context) {

   }

   }

2. Introduce the 3DRenderer class as shown below:

   Public class 3DRenderer implements GLSurfaceView.Renderer {

   Private static final String

   Private float ;

   Private float ;

   Private float ;

   Define each float color above.

3. Create the documentation for the project using the normal programming procedure.

Tips & Warnings

• The "SurfaceView" function acts like a canvas where the environment can be drawn. It is embedded in the API making it viewable.

• The "onsurfaceCreated" function is used to set up elements that do not change such as the color that clears the screen during events and so on.

• The "onDrawFrame" call is used to define the actual drawing space.

• The "onSurfaceChanged" function is called when a device flips between the portrait and the landscape views.

• If you are more focused on implementation rather than how Androids handle OpenGL, use OpenGL examples as templates which will speed up your projects.

• As you progress, you will be able to rotate drawn objects on different axis. Other elements can be defined that specify the angle, the speed and mouse activities that affect these rotation parameters.

References

• JayWay: Setting Up the OpenGL ES Tutorial for Android
• Android Developers: Introducing GLSurfaceView

Resources

• Khronos: OpenGL ES OverView