how to label a cuboid using open gl?
- by usha
hi this is how my 3dcuboid looks ,i have attached complete code , i want to label this cuboid using different name across sides how is it possible using opengl in android...plz help me out
public class MyGLRenderer implements Renderer {
Context context;
Cuboid rect;
private float mCubeRotation;
// private static float angleCube = 0; // Rotational angle in degree for cube (NEW)
// private static float speedCube = -1.5f; // Rotational speed for cube (NEW)
public MyGLRenderer(Context context) {
rect = new Cuboid();
this.context = context;
}
public void onDrawFrame(GL10 gl) {
// TODO Auto-generated method stub
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity(); // Reset the model-view matrix
gl.glTranslatef(0.2f, 0.0f, -8.0f); // Translate right and into the screen
gl.glScalef(0.8f, 0.8f, 0.8f); // Scale down (NEW)
gl.glRotatef(mCubeRotation, 1.0f, 1.0f, 1.0f);
// gl.glRotatef(angleCube, 1.0f, 1.0f, 1.0f); // rotate about the axis (1,1,1) (NEW)
rect.draw(gl);
mCubeRotation -= 0.15f;
//angleCube += speedCube;
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
// TODO Auto-generated method stub
if (height == 0) height = 1; // To prevent divide by zero
float aspect = (float)width / height;
// Set the viewport (display area) to cover the entire window
gl.glViewport(0, 0, width, height);
// Setup perspective projection, with aspect ratio matches viewport
gl.glMatrixMode(GL10.GL_PROJECTION); // Select projection matrix
gl.glLoadIdentity(); // Reset projection matrix
// Use perspective projection
GLU.gluPerspective(gl, 45, aspect, 0.1f, 100.f);
gl.glMatrixMode(GL10.GL_MODELVIEW); // Select model-view matrix
gl.glLoadIdentity(); // Reset
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// TODO Auto-generated method stub
gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Set color's clear-value to black
gl.glClearDepthf(1.0f); // Set depth's clear-value to farthest
gl.glEnable(GL10.GL_DEPTH_TEST); // Enables depth-buffer for hidden surface removal
gl.glDepthFunc(GL10.GL_LEQUAL); // The type of depth testing to do
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST); // nice perspective view
gl.glShadeModel(GL10.GL_SMOOTH); // Enable smooth shading of color
gl.glDisable(GL10.GL_DITHER); // Disable dithering for better performance
}}
public class Cuboid{
private FloatBuffer mVertexBuffer;
private FloatBuffer mColorBuffer;
private ByteBuffer mIndexBuffer;
private float vertices[] = {
//width,height,depth
-2.5f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
-2.5f, 1.0f, -1.0f,
-2.5f, -1.0f, 1.0f,
1.0f, -1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
-2.5f, 1.0f, 1.0f
};
private float colors[] = {
// R,G,B,A COLOR
0.0f, 1.0f, 0.0f, 1.0f,
0.0f, 1.0f, 0.0f, 1.0f,
1.0f, 0.5f, 0.0f, 1.0f,
1.0f, 0.5f, 0.0f, 1.0f,
1.0f, 0.0f, 0.0f, 1.0f,
1.0f, 0.0f, 0.0f, 1.0f,
0.0f, 0.0f, 1.0f, 1.0f,
1.0f, 0.0f, 1.0f, 1.0f
};
private byte indices[] = {
// VERTEX 0,1,2,3,4,5,6,7 REPRESENTATION FOR FACES
0, 4, 5, 0, 5, 1,
1, 5, 6, 1, 6, 2,
2, 6, 7, 2, 7, 3,
3, 7, 4, 3, 4, 0,
4, 7, 6, 4, 6, 5,
3, 0, 1, 3, 1, 2
};
public Cuboid() {
ByteBuffer byteBuf = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
mVertexBuffer = byteBuf.asFloatBuffer();
mVertexBuffer.put(vertices);
mVertexBuffer.position(0);
byteBuf = ByteBuffer.allocateDirect(colors.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
mColorBuffer = byteBuf.asFloatBuffer();
mColorBuffer.put(colors);
mColorBuffer.position(0);
mIndexBuffer = ByteBuffer.allocateDirect(indices.length);
mIndexBuffer.put(indices);
mIndexBuffer.position(0);
}
public void draw(GL10 gl) {
gl.glFrontFace(GL10.GL_CW);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mVertexBuffer);
gl.glColorPointer(4, GL10.GL_FLOAT, 0, mColorBuffer);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
gl.glDrawElements(GL10.GL_TRIANGLES, 36, GL10.GL_UNSIGNED_BYTE,
mIndexBuffer);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_COLOR_ARRAY);
}
}
public class Draw3drect extends Activity {
private GLSurfaceView glView; // Use GLSurfaceView
// Call back when the activity is started, to initialize the view
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
glView = new GLSurfaceView(this); // Allocate a GLSurfaceView
glView.setRenderer(new MyGLRenderer(this)); // Use a custom renderer
this.setContentView(glView); // This activity sets to GLSurfaceView
}
// Call back when the activity is going into the background
@Override
protected void onPause() {
super.onPause();
glView.onPause();
}
// Call back after onPause()
@Override
protected void onResume() {
super.onResume();
glView.onResume();
}
}
