RayPickDebug.java :  » UnTagged » truesculpt » truesculpt » renderer » Android Open Source

package truesculpt.renderer;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;

import javax.microedition.khronos.opengles.GL10;

/**
 * A vertex shaded cube.
 */
public class RayPickDebug
{
  private FloatBuffer mColorBuffer;
  private ShortBuffer mIndexBuffer;
  private FloatBuffer mVertexBuffer;

  public RayPickDebug()
  {
    float zero = 0.0f;
    float one = 1.0f;
    float vertices[] = { zero, zero, zero, zero, zero, zero };

    float colors[] = { one, one, one, one, one, one, one, one };

    short indices[] = { 0, 1 };

    // Buffers to be passed to gl*Pointer() functions
    // must be direct, i.e., they must be placed on the
    // native heap where the garbage collector cannot
    // move them.
    //
    // Buffers with multi-byte datatypes (e.g., short, int, float)
    // must have their byte order set to native order

    ByteBuffer vbb = ByteBuffer.allocateDirect(2 * 3 * 4);
    vbb.order(ByteOrder.nativeOrder());
    mVertexBuffer = vbb.asFloatBuffer();
    mVertexBuffer.put(vertices);

    ByteBuffer cbb = ByteBuffer.allocateDirect(2 * 4 * 4);
    cbb.order(ByteOrder.nativeOrder());
    mColorBuffer = cbb.asFloatBuffer();
    mColorBuffer.put(colors);

    ByteBuffer ibb = ByteBuffer.allocateDirect(2 * 2);
    ibb.order(ByteOrder.nativeOrder());
    mIndexBuffer = ibb.asShortBuffer();
    mIndexBuffer.put(indices);
  }

  public void draw(GL10 gl)
  {
    mVertexBuffer.position(0);
    mIndexBuffer.position(0);  
    mColorBuffer.position(0);
    
    gl.glEnableClientState(GL10.GL_COLOR_ARRAY);

    gl.glFrontFace(GL10.GL_CW);
    gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mVertexBuffer);
    gl.glColorPointer(4, GL10.GL_FLOAT, 0, mColorBuffer);
    gl.glDrawElements(GL10.GL_LINE_STRIP, 2, GL10.GL_UNSIGNED_SHORT, mIndexBuffer);

    gl.glDisableClientState(GL10.GL_COLOR_ARRAY);
  }

  public void setRayPos(float[] pt1, float[] pt2)
  {
    mVertexBuffer.position(0);
    mVertexBuffer.put(pt1);
    mVertexBuffer.put(pt2);
  }
}