Example #1
0
  @Override
  public void apply(final double dt, final Particle particle, final int index) {
    if (_wanderRadius == 0 && _wanderDistance == 0 && _wanderJitter == 0) {
      return;
    }

    final Vector3 wanderTarget = _wanderTargets.get(index);

    wanderTarget.addLocal(calcNewJitter(), calcNewJitter(), calcNewJitter());
    wanderTarget.normalizeLocal();
    wanderTarget.multiplyLocal(_wanderRadius);

    _workVect.set(particle.getVelocity()).normalizeLocal().multiplyLocal(_wanderDistance);
    _workVect.addLocal(wanderTarget).normalizeLocal();
    _workVect.multiplyLocal(particle.getVelocity().length());
    particle.getVelocity().set(_workVect);
  }
Example #2
0
  private void setGeometryData() {
    final FloatBuffer verts = _meshData.getVertexBuffer();
    final FloatBuffer norms = _meshData.getNormalBuffer();
    final FloatBuffer texs = _meshData.getTextureBuffer(0);
    verts.rewind();
    norms.rewind();
    texs.rewind();

    // generate geometry
    final double inverseRadial = 1.0 / radialSamples;
    final double inverseSphere = 1.0 / sphereSamples;
    final double halfHeight = 0.5 * height;

    // Generate points on the unit circle to be used in computing the mesh
    // points on a cylinder slice.
    final double[] sin = new double[radialSamples + 1];
    final double[] cos = new double[radialSamples + 1];

    for (int radialCount = 0; radialCount < radialSamples; radialCount++) {
      final double angle = MathUtils.TWO_PI * inverseRadial * radialCount;
      cos[radialCount] = MathUtils.cos(angle);
      sin[radialCount] = MathUtils.sin(angle);
    }
    sin[radialSamples] = sin[0];
    cos[radialSamples] = cos[0];

    final Vector3 tempA = new Vector3();

    // top point.
    verts.put(0).put((float) (radius + halfHeight)).put(0);
    norms.put(0).put(1).put(0);
    texs.put(1).put(1);

    // generating the top dome.
    for (int i = 0; i < sphereSamples; i++) {
      final double center = radius * (1 - (i + 1) * (inverseSphere));
      final double lengthFraction = (center + height + radius) / (height + 2 * radius);

      // compute radius of slice
      final double fSliceRadius = Math.sqrt(Math.abs(radius * radius - center * center));

      for (int j = 0; j <= radialSamples; j++) {
        final Vector3 kRadial = tempA.set(cos[j], 0, sin[j]);
        kRadial.multiplyLocal(fSliceRadius);
        verts.put(kRadial.getXf()).put((float) (center + halfHeight)).put(kRadial.getZf());
        kRadial.setY(center);
        kRadial.normalizeLocal();
        norms.put(kRadial.getXf()).put(kRadial.getYf()).put(kRadial.getZf());
        final double radialFraction = 1 - (j * inverseRadial); // in [0,1)
        texs.put((float) radialFraction).put((float) lengthFraction);
      }
    }

    // generate cylinder... but no need to add points for first and last
    // samples as they are already part of domes.
    for (int i = 1; i < axisSamples; i++) {
      final double center = halfHeight - (i * height / axisSamples);
      final double lengthFraction = (center + halfHeight + radius) / (height + 2 * radius);

      for (int j = 0; j <= radialSamples; j++) {
        final Vector3 kRadial = tempA.set(cos[j], 0, sin[j]);
        kRadial.multiplyLocal(radius);
        verts.put(kRadial.getXf()).put((float) center).put(kRadial.getZf());
        kRadial.normalizeLocal();
        norms.put(kRadial.getXf()).put(kRadial.getYf()).put(kRadial.getZf());
        final double radialFraction = 1 - (j * inverseRadial); // in [0,1)
        texs.put((float) radialFraction).put((float) lengthFraction);
      }
    }

    // generating the bottom dome.
    for (int i = 0; i < sphereSamples; i++) {
      final double center = i * (radius / sphereSamples);
      final double lengthFraction = (radius - center) / (height + 2 * radius);

      // compute radius of slice
      final double fSliceRadius = Math.sqrt(Math.abs(radius * radius - center * center));

      for (int j = 0; j <= radialSamples; j++) {
        final Vector3 kRadial = tempA.set(cos[j], 0, sin[j]);
        kRadial.multiplyLocal(fSliceRadius);
        verts.put(kRadial.getXf()).put((float) (-center - halfHeight)).put(kRadial.getZf());
        kRadial.setY(-center);
        kRadial.normalizeLocal();
        norms.put(kRadial.getXf()).put(kRadial.getYf()).put(kRadial.getZf());
        final double radialFraction = 1 - (j * inverseRadial); // in [0,1)
        texs.put((float) radialFraction).put((float) lengthFraction);
      }
    }

    // bottom point.
    verts.put(0).put((float) (-radius - halfHeight)).put(0);
    norms.put(0).put(-1).put(0);
    texs.put(0).put(0);
  }