internal WheelJoint(WheelJointDef def) : base(def)
{
m_localAnchorA = def.localAnchorA;
m_localAnchorB = def.localAnchorB;
m_localXAxisA = def.localAxisA;
m_localYAxisA = Utilities.Cross(1.0f, m_localXAxisA);
m_mass = 0.0f;
m_impulse = 0.0f;
m_motorMass = 0.0f;
m_motorImpulse = 0.0f;
m_springMass = 0.0f;
m_springImpulse = 0.0f;
m_maxMotorTorque = def.maxMotorTorque;
m_motorSpeed = def.motorSpeed;
m_enableMotor = def.enableMotor;
m_frequencyHz = def.frequencyHz;
m_dampingRatio = def.dampingRatio;
m_bias = 0.0f;
m_gamma = 0.0f;
m_ax.SetZero();
m_ay.SetZero();
}
internal WheelJoint(WheelJointDef def): base(def)
{
m_localAnchorA = def.localAnchorA;
m_localAnchorB = def.localAnchorB;
m_localXAxisA = def.localAxisA;
m_localYAxisA = Utilities.Cross(1.0f, m_localXAxisA);
m_mass = 0.0f;
m_impulse = 0.0f;
m_motorMass = 0.0f;
m_motorImpulse = 0.0f;
m_springMass = 0.0f;
m_springImpulse = 0.0f;
m_maxMotorTorque = def.maxMotorTorque;
m_motorSpeed = def.motorSpeed;
m_enableMotor = def.enableMotor;
m_frequencyHz = def.frequencyHz;
m_dampingRatio = def.dampingRatio;
m_bias = 0.0f;
m_gamma = 0.0f;
m_ax.SetZero();
m_ay.SetZero();
}
public Car()
{
m_hz = 4.0f;
m_zeta = 0.7f;
m_speed = 50.0f;
Body ground = null;
{
BodyDef bd = new BodyDef();
ground = m_world.CreateBody(bd);
EdgeShape shape = new EdgeShape();
FixtureDef fd = new FixtureDef();
fd.shape = shape;
fd.Density = 0.0f;
fd.friction = 0.6f;
shape.Set(new Vec2(-20.0f, 0.0f), new Vec2(20.0f, 0.0f));
ground.CreateFixture(fd);
float[] hs = new float[]{0.25f, 1.0f, 4.0f, 0.0f, 0.0f, -1.0f, -2.0f, -2.0f, -1.25f, 0.0f};
float x = 20.0f, y1 = 0.0f, dx = 5.0f;
for (int i = 0; i < 10; ++i)
{
float y2 = hs[i];
shape.Set(new Vec2(x, y1), new Vec2(x + dx, y2));
ground.CreateFixture(fd);
y1 = y2;
x += dx;
}
for (int i = 0; i < 10; ++i)
{
float y2 = hs[i];
shape.Set(new Vec2(x, y1), new Vec2(x + dx, y2));
ground.CreateFixture(fd);
y1 = y2;
x += dx;
}
shape.Set(new Vec2(x, 0.0f), new Vec2(x + 40.0f, 0.0f));
ground.CreateFixture(fd);
x += 80.0f;
shape.Set(new Vec2(x, 0.0f), new Vec2(x + 40.0f, 0.0f));
ground.CreateFixture(fd);
x += 40.0f;
shape.Set(new Vec2(x, 0.0f), new Vec2(x + 10.0f, 5.0f));
ground.CreateFixture(fd);
x += 20.0f;
shape.Set(new Vec2(x, 0.0f), new Vec2(x + 40.0f, 0.0f));
ground.CreateFixture(fd);
x += 40.0f;
shape.Set(new Vec2(x, 0.0f), new Vec2(x, 20.0f));
ground.CreateFixture(fd);
}
// Teeter
{
BodyDef bd = new BodyDef();
bd.Position.Set(140.0f, 1.0f);
bd.type = BodyType._dynamicBody;
Body body = m_world.CreateBody(bd);
PolygonShape box = new PolygonShape();
box.SetAsBox(10.0f, 0.25f);
box.Density = 1;
body.CreateFixture(box);
RevoluteJointDef jd = new RevoluteJointDef();
jd.Initialize(ground, body, body.GetPosition());
jd.lowerAngle = -8.0f * (float)Math.PI / 180.0f;
jd.upperAngle = 8.0f * (float)Math.PI / 180.0f;
jd.enableLimit = true;
m_world.CreateJoint(jd);
body.ApplyAngularImpulse(100.0f, true);
}
// Bridge
{
int N = 20;
PolygonShape shape = new PolygonShape();
shape.SetAsBox(1.0f, 0.125f);
FixtureDef fd = new FixtureDef();
fd.shape = shape;
fd.Density = 1.0f;
fd.friction = 0.6f;
RevoluteJointDef jd = new RevoluteJointDef();
Body prevBody = ground;
for (int i = 0; i < N; ++i)
{
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.Position.Set(161.0f + 2.0f * i, -0.125f);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
Vec2 anchor = new Vec2(160.0f + 2.0f * i, -0.125f);
jd.Initialize(prevBody, body, anchor);
m_world.CreateJoint(jd);
prevBody = body;
}
Vec2 anchor2 = new Vec2(160.0f + 2.0f * N, -0.125f);
jd.Initialize(prevBody, ground, anchor2);
m_world.CreateJoint(jd);
}
// Boxes
{
PolygonShape box = new PolygonShape();
box.SetAsBox(0.5f, 0.5f);
box.Density = 0.5f;
Body body = null;
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.Position.Set(230.0f, 0.5f);
body = m_world.CreateBody(bd);
body.CreateFixture(box);
bd.Position.Set(230.0f, 1.5f);
body = m_world.CreateBody(bd);
body.CreateFixture(box);
bd.Position.Set(230.0f, 2.5f);
body = m_world.CreateBody(bd);
body.CreateFixture(box);
bd.Position.Set(230.0f, 3.5f);
body = m_world.CreateBody(bd);
body.CreateFixture(box);
bd.Position.Set(230.0f, 4.5f);
body = m_world.CreateBody(bd);
body.CreateFixture(box);
}
// Car
{
PolygonShape chassis = new PolygonShape();
Vec2[] vertices = new Vec2[8];
vertices[0].Set(-1.5f, -0.5f);
vertices[1].Set(1.5f, -0.5f);
vertices[2].Set(1.5f, 0.0f);
vertices[3].Set(0.0f, 0.9f);
vertices[4].Set(-1.15f, 0.9f);
vertices[5].Set(-1.5f, 0.2f);
chassis.Set(vertices, 6);
CircleShape circle = new CircleShape();
circle.m_radius = 0.4f;
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.Position.Set(0.0f, 1.0f);
m_car = m_world.CreateBody(bd);
m_car.CreateFixture(chassis);
FixtureDef fd = new FixtureDef();
fd.shape = circle;
fd.Density = 1.0f;
fd.friction = 0.9f;
bd.Position.Set(-1.0f, 0.35f);
m_wheel1 = m_world.CreateBody(bd);
m_wheel1.CreateFixture(fd);
bd.Position.Set(1.0f, 0.4f);
m_wheel2 = m_world.CreateBody(bd);
m_wheel2.CreateFixture(fd);
WheelJointDef jd = new WheelJointDef();
Vec2 axis = new Vec2(0.0f, 1.0f);
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);
}
}
