BulletTest.java

package org.jbox2d.testbed.tests;

import org.jbox2d.collision.Distance;
import org.jbox2d.collision.TimeOfImpact;
import org.jbox2d.collision.shapes.EdgeShape;
import org.jbox2d.collision.shapes.PolygonShape;
import org.jbox2d.common.MathUtils;
import org.jbox2d.common.Vec2;
import org.jbox2d.dynamics.Body;
import org.jbox2d.dynamics.BodyDef;
import org.jbox2d.dynamics.BodyType;
import org.jbox2d.testbed.framework.TestbedSettings;
import org.jbox2d.testbed.framework.TestbedTest;

public class BulletTest extends TestbedTest {

  Body m_body;
  Body m_bullet;
  float m_x;
  
  @Override
  public Vec2 getDefaultCameraPos() {
    return new Vec2(0, 6);
  }
  
  @Override
  public float getDefaultCameraScale() {
    return 40;
  }

  @Override
  public void initTest(boolean deserialized) {
    {
      BodyDef bd = new BodyDef();
      bd.position.set(0.0f, 0.0f);
      Body body = m_world.createBody(bd);

      EdgeShape edge = new EdgeShape();

      edge.set(new Vec2(-10.0f, 0.0f), new Vec2(10.0f, 0.0f));
      body.createFixture(edge, 0.0f);

      PolygonShape shape = new PolygonShape();
      shape.setAsBox(0.2f, 1.0f, new Vec2(0.5f, 1.0f), 0.0f);
      body.createFixture(shape, 0.0f);
    }

    {
      BodyDef bd = new BodyDef();
      bd.type = BodyType.DYNAMIC;
      bd.position.set(0.0f, 4.0f);

      PolygonShape box = new PolygonShape();
      box.setAsBox(2.0f, 0.1f);

      m_body = m_world.createBody(bd);
      m_body.createFixture(box, 1.0f);

      box.setAsBox(0.25f, 0.25f);

      // m_x = RandomFloat(-1.0f, 1.0f);
      m_x = -0.06530577f;
      bd.position.set(m_x, 10.0f);
      bd.bullet = true;

      m_bullet = m_world.createBody(bd);
      m_bullet.createFixture(box, 100.0f);

      m_bullet.setLinearVelocity(new Vec2(0.0f, -50.0f));
    }
  }

  public void launch() {
    m_body.setTransform(new Vec2(0.0f, 4.0f), 0.0f);
    m_body.setLinearVelocity(new Vec2());
    m_body.setAngularVelocity(0.0f);

    m_x = MathUtils.randomFloat(-1.0f, 1.0f);
    m_bullet.setTransform(new Vec2(m_x, 10.0f), 0.0f);
    m_bullet.setLinearVelocity(new Vec2(0.0f, -50.0f));
    m_bullet.setAngularVelocity(0.0f);

    Distance.GJK_CALLS = 0;
    Distance.GJK_ITERS = 0;
    Distance.GJK_MAX_ITERS = 0;

    TimeOfImpact.toiCalls = 0;
    TimeOfImpact.toiIters = 0;
    TimeOfImpact.toiMaxIters = 0;
    TimeOfImpact.toiRootIters = 0;
    TimeOfImpact.toiMaxRootIters = 0;
  }

  @Override
  public void step(TestbedSettings settings) {
    super.step(settings);


    if (Distance.GJK_CALLS > 0) {
      addTextLine(String.format("gjk calls = %d, ave gjk iters = %3.1f, max gjk iters = %d",
          Distance.GJK_CALLS, Distance.GJK_ITERS * 1.0 / (Distance.GJK_CALLS),
          Distance.GJK_MAX_ITERS));
    }

    if (TimeOfImpact.toiCalls > 0) {
      addTextLine(String.format("toi calls = %d, ave toi iters = %3.1f, max toi iters = %d",
          TimeOfImpact.toiCalls, TimeOfImpact.toiIters * 1f / (TimeOfImpact.toiCalls),
          TimeOfImpact.toiMaxRootIters));

      addTextLine(String.format("ave toi root iters = %3.1f, max toi root iters = %d",
          TimeOfImpact.toiRootIters * 1f / (TimeOfImpact.toiCalls), TimeOfImpact.toiMaxRootIters));
    }

    if (getStepCount() % 60 == 0) {
      launch();
    }
  }

  @Override
  public String getTestName() {
    return "Bullet Test";
  }

}