/*
* Sample code for M3G article on IBM developerWorks.
* http://www.ibm.com/developerworks/
*/
package m3gsamples1;
import javax.microedition.lcdui.*;
import javax.microedition.m3g.*;
/**
* Sample displaying a cube defined by eight vertices which are connected
* by triangles.
*
* @author Claus Hoefele
*/
public class VerticesSample extends Canvas implements Sample
{
/** The cube"s vertex positions (x, y, z). */
private static final byte[] VERTEX_POSITIONS = {
-1, -1, 1, 1, -1, 1, -1, 1, 1, 1, 1, 1,
-1, -1, -1, 1, -1, -1, -1, 1, -1, 1, 1, -1
};
/** Indices that define how to connect the vertices to build
* triangles. */
private static int[] TRIANGLE_INDICES = {
0, 1, 2, 3, 7, 1, 5, 4, 7, 6, 2, 4, 0, 1
};
/** The cube"s vertex data. */
private VertexBuffer _cubeVertexData;
/** The cube"s triangles defined as triangle strips. */
private TriangleStripArray _cubeTriangles;
/** Graphics singleton used for rendering. */
private Graphics3D _graphics3d;
/**
* Called when this sample is displayed.
*/
public void showNotify()
{
init();
}
/**
* Initializes the sample.
*/
protected void init()
{
// Get the singleton for 3D rendering.
_graphics3d = Graphics3D.getInstance();
// Create vertex data.
_cubeVertexData = new VertexBuffer();
VertexArray vertexPositions =
new VertexArray(VERTEX_POSITIONS.length/3, 3, 1);
vertexPositions.set(0, VERTEX_POSITIONS.length/3, VERTEX_POSITIONS);
_cubeVertexData.setPositions(vertexPositions, 1.0f, null);
// Create the triangles that define the cube; the indices point to
// vertices in VERTEX_POSITIONS.
_cubeTriangles = new TriangleStripArray(TRIANGLE_INDICES,
new int[] {TRIANGLE_INDICES.length});
// Create a camera with perspective projection.
Camera camera = new Camera();
float aspect = (float) getWidth() / (float) getHeight();
camera.setPerspective(30.0f, aspect, 1.0f, 1000.0f);
Transform cameraTransform = new Transform();
cameraTransform.postTranslate(0.0f, 0.0f, 10.0f);
_graphics3d.setCamera(camera, cameraTransform);
}
/**
* Renders the sample on the screen.
*
* @param graphics the graphics object to draw on.
*/
protected void paint(Graphics graphics)
{
_graphics3d.bindTarget(graphics);
_graphics3d.clear(null);
_graphics3d.render(_cubeVertexData, _cubeTriangles,
new Appearance(), null);
_graphics3d.releaseTarget();
}
/**
* Returns the <code>Displayable</code> used to display this sample.
*
* @return display
*/
public Displayable getDisplayable()
{
return this;
}
/**
* Returns the display name of this sample.
*
* @return name
*/
public String getName()
{
return "Cube Vertices";
}
}
|
