我想在java中使用libgdx和box2d制作一个可移动的汽车; 我做了一辆车,m_car,位置设置在车中间。 在每一步,我采取m_car的当前位置,减少值与汽车的宽度/高度,所以我有左下角。当在直线地面上时,它表现出色,纹理应该是在哪里,但是当地面有一个角度时,纹理将定位在其下面或上方。 我不明白TextureRegion是如何工作的,我认为当角度不是0时,我没有把握得好,我不知道如何解决它。帮我请他:) Ty。使用textureRegion的绘制
编辑:
我的代码是一个烂摊子,它不是一个实际的项目,它的IDEEA,我就拿块,并把它们记录下来,看看他们是如何工作的,所以当IL启动该项目,我会知道该怎么做,这是我的汽车宣言:
private void car2(){
m_hz = 5.0f;
m_zeta = 0.7f;
m_speed = 50.0f;
BodyDef bd = new BodyDef();
bd.type = BodyType.DynamicBody;
part1(bd);
part2(bd);
part3(bd);
wheels(bd);
m_car.setAwake(true);
}
private void part3(BodyDef bd) {
PolygonShape shape = new PolygonShape();
shape.setAsBox(0.01f, 0.35f,new Vector2(1.01f - 3, 4.85f - 4), 0);
m_car.createFixture(shape, 1.0f);
}
private void part1(BodyDef bd){
PolygonShape chassis = new PolygonShape();
Vector2 vertices[] = new Vector2[6];
vertices[0] = new Vector2(-2, -0.5f);
vertices[1] = new Vector2(-2, 0.5f);
vertices[2] = new Vector2(1.25f, 0.5f);
vertices[3] = new Vector2(2.5f, 0.15f);
vertices[4] = new Vector2(2.5f, -0.5f);
vertices[5] = new Vector2(-2, -0.5f);
chassis.set(vertices);
bd.position.set(new Vector2(3, 4));
m_car = m_world.createBody(bd);
m_car.createFixture(chassis, 1.0f);
}
private void part2(BodyDef bd){
PolygonShape chassis = new PolygonShape();
Vector2 vertices[] = new Vector2[5];
vertices[0] = new Vector2(3, 4.5f);
vertices[1] = new Vector2(3, 5.25f);
vertices[2] = new Vector2(3.80f, 5.25f);
vertices[3] = new Vector2(4.25f, 4.5f);
vertices[4] = new Vector2(3, 4.5f);
for (int i = 0; i < 5; ++ i){
vertices[i].x -= 3;
vertices[i].y -= 4;
}
chassis.set(vertices);
//m_car = m_world.createBody(bd);
m_car.createFixture(chassis, 1.0f);
}
private void wheels(BodyDef bd){
CircleShape circle = new CircleShape();
circle.setRadius(0.4f);
FixtureDef fd = new FixtureDef();
fd.shape = circle;
fd.density = 1.0f;
fd.friction = 0.9f;
bd.position.set(2f, 3.5f);
m_wheel1 = m_world.createBody(bd);
m_wheel1.createFixture(fd);
bd.position.set(4.5f, 3.5f);
m_wheel2 = m_world.createBody(bd);
m_wheel2.createFixture(fd);
WheelJointDef jd = new WheelJointDef();
Vector2 axis = new Vector2(1.0f, 0.5f);
jd.initialize(m_car, m_wheel1, m_wheel1.getPosition(), axis);
jd.motorSpeed = 0.0f;
jd.maxMotorTorque = 20.0f;
jd.enableMotor = true;
jd.frequencyHz = m_hz;
jd.dampingRatio = m_zeta;
m_spring1 = (WheelJoint) m_world.createJoint(jd);
jd.initialize(m_car, m_wheel2, m_wheel2.getPosition(), axis);
jd.motorSpeed = 0.0f;
jd.maxMotorTorque = 10.0f;
jd.enableMotor = false;
jd.frequencyHz = m_hz;
jd.dampingRatio = m_zeta;
m_spring2 = (WheelJoint) m_world.createJoint(jd);
}
一些explenation:为什么我要为顶点来判断3和4?我不知道,如果我设置位置的bodydef,顶点认为这一点是0,0,当我发现,是easyer我只是减少(因为它只是为了测试,看看它是如何工作的)
,这是我画:
float angle = (float) Math.toDegrees(m_car.getAngle());
batch.draw(textureRegion, x, y, 3f, 4f,
4.5f, 2.75f, 1f, 0.61f, angle);
ty for info :)我给纹理区域的角度,但不是绘制的好位置:这是我的问题: https://www.dropbox.com/s/divt8fbg3jri6go/Untitled4.jpg 角度是好的,它的定位不好,以及idk为什么,可能当角度改变时,绘制位置发生变化,但是idk如何改变,我应该给出什么位置 –
这看起来可能是原点问题。如果身体/图片的来源不同,或者不在汽车中间,图片可能会上下移动,具体取决于角度。但没有更多的代码只是猜测 – noone
原点必须是纹理的中心吗? –