public BulletTest()
{
{
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));
edge.Density = 0;
body.CreateFixture(edge);
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.2f, 1.0f, new Vec2(0.5f, 1.0f), 0.0f);
shape.Density = 0;
body.CreateFixture(shape);
}
{
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.Position.Set(0.0f, 4.0f);
PolygonShape box = new PolygonShape();
box.SetAsBox(2.0f, 0.1f);
box.Density = 100;
m_body = m_world.CreateBody(bd);
m_body.CreateFixture(box);
box.SetAsBox(0.25f, 0.25f);
//m_x = RandomFloat(-1.0f, 1.0f);
m_x = 0.20352793f;
bd.Position.Set(m_x, 10.0f);
bd.bullet = true;
m_bullet = m_world.CreateBody(bd);
m_bullet.CreateFixture(box);
m_bullet.SetLinearVelocity(new Vec2(0.0f, -50.0f));
}
}
public ApplyForce() {
m_world.SetGravity(new Vec2(0.0f, 0.0f));
const float k_restitution = 0.4f;
Body ground;
{
BodyDef bd = new BodyDef();
bd.Position.Set(0.0f, 20.0f);
ground = m_world.CreateBody(bd);
EdgeShape shape = new EdgeShape();
FixtureDef sd = new FixtureDef();
sd.shape = shape;
sd.Density = 0.0f;
sd.restitution = k_restitution;
// Left vertical
shape.Set(new Vec2(-20.0f, -20.0f), new Vec2(-20.0f, 20.0f));
ground.CreateFixture(sd);
// Right vertical
shape.Set(new Vec2(20.0f, -20.0f), new Vec2(20.0f, 20.0f));
ground.CreateFixture(sd);
// Top horizontal
shape.Set(new Vec2(-20.0f, 20.0f), new Vec2(20.0f, 20.0f));
ground.CreateFixture(sd);
// Bottom horizontal
shape.Set(new Vec2(-20.0f, -20.0f), new Vec2(20.0f, -20.0f));
ground.CreateFixture(sd);
}
{
Transform xf1 = new Transform();
xf1.q.Set(0.3524f * (float)Math.PI);
xf1.p = xf1.q.GetXAxis();
Vec2[] vertices = new Vec2[3];
vertices[0] = Utilities.Mul(xf1, new Vec2(-1.0f, 0.0f));
vertices[1] = Utilities.Mul(xf1, new Vec2(1.0f, 0.0f));
vertices[2] = Utilities.Mul(xf1, new Vec2(0.0f, 0.5f));
PolygonShape poly1 = new PolygonShape();
poly1.Set(vertices, 3);
FixtureDef sd1 = new FixtureDef();
sd1.shape = poly1;
sd1.Density = 4.0f;
Transform xf2 = new Transform();
xf2.q.Set(-0.3524f * (float)Math.PI);
xf2.p = -xf2.q.GetXAxis();
vertices[0] = Utilities.Mul(xf2, new Vec2(-1.0f, 0.0f));
vertices[1] = Utilities.Mul(xf2, new Vec2(1.0f, 0.0f));
vertices[2] = Utilities.Mul(xf2, new Vec2(0.0f, 0.5f));
PolygonShape poly2 = new PolygonShape();
poly2.Set(vertices, 3);
FixtureDef sd2 = new FixtureDef();
sd2.shape = poly2;
sd2.Density = 2.0f;
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.angularDamping = 5.0f;
bd.linearDamping = 0.1f;
bd.Position.Set(0.0f, 2.0f);
bd.angle = (float)Math.PI;
bd.allowSleep = false;
m_body = m_world.CreateBody(bd);
m_body.CreateFixture(sd1);
m_body.CreateFixture(sd2);
}
{
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.5f, 0.5f);
FixtureDef fd = new FixtureDef();
fd.shape = shape;
fd.Density = 1.0f;
fd.friction = 0.3f;
for (int i = 0; i < 10; ++i) {
BodyDef bd = new BodyDef();
bd.type = BodyType._dynamicBody;
bd.Position.Set(0.0f, 5.0f + 1.54f * i);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
float gravity = 10.0f;
float I = body.GetInertia();
float mass = body.GetMass();
// For a circle: I = 0.5 * m * r * r ==> r = sqrt(2 * I / m)
float radius = (float)Math.Sqrt(2.0f * I / mass);
FrictionJointDef jd = new FrictionJointDef();
jd.localAnchorA.SetZero();
jd.localAnchorB.SetZero();
jd.bodyA = ground;
jd.bodyB = body;
jd.collideConnected = true;
jd.maxForce = mass * gravity;
jd.maxTorque = mass * radius * gravity;
m_world.CreateJoint(jd);
}
}
}
static void Main(string[] args)
{
// Define the size of the world. Simulation will still work
// if bodies reach the end of the world, but it will be slower.
AABB worldAABB = new AABB
{
UpperBound = new Vector2(100, 100),
LowerBound = new Vector2(-100, -100)
};
// Define the gravity vector.
Vector2 gravity = new Vector2(0.0f, -10.0f);
// Do we want to let bodies sleep?
bool doSleep = true;
// Construct a world object, which will hold and simulate the rigid bodies.
World world = new World(worldAABB, gravity, doSleep);
// Define the ground body.
BodyDef groundBodyDef = new BodyDef();
groundBodyDef.Position = new Vector2(0.0f, -10.0f);
// Call the body factory which creates the ground box shape.
// The body is also added to the world.
Body groundBody = world.CreateBody(groundBodyDef);
// Define the ground box shape.
PolygonDef groundShapeDef = new PolygonDef();
// The extents are the half-widths of the box.
groundShapeDef.SetAsBox(50.0f, 10.0f);
// Add the ground shape to the ground body.
groundBody.CreateFixture(groundShapeDef);
// Define the dynamic body. We set its position and call the body factory.
BodyDef bodyDef = new BodyDef();
bodyDef.Position = new Vector2(0.0f, 4.0f);
Body body = world.CreateBody(bodyDef);
// Define another box shape for our dynamic body.
PolygonDef shapeDef = new PolygonDef();
shapeDef.SetAsBox(1.0f, 1.0f);
// Set the box density to be non-zero, so it will be dynamic.
shapeDef.Density = 1.0f;
// Override the default friction.
shapeDef.Friction = 0.3f;
// Add the shape to the body.
body.CreateFixture(shapeDef);
// Now tell the dynamic body to compute it's mass properties base
// on its shape.
body.SetMassFromShapes();
// Prepare for simulation. Typically we use a time step of 1/60 of a
// second (60Hz) and 10 iterations. This provides a high quality simulation
// in most game scenarios.
float timeStep = 1.0f / 60.0f;
int velocityIterations = 8;
int positionIterations = 1;
// This is our little game loop.
for (int i = 0; i < 100; ++i)
{
// Instruct the world to perform a single step of simulation. It is
// generally best to keep the time step and iterations fixed.
world.Step(timeStep, velocityIterations, positionIterations);
// Now print the position and angle of the body.
Vector2 position = body.GetPosition();
float angle = body.GetAngle();
Console.WriteLine("Step: {3} - X: {0}, Y: {1}, Angle: {2}", new object[] { position.X.ToString(), position.Y.ToString(), angle.ToString(), i.ToString() });
}
// When the world destructor is called, all bodies and joints are freed. This can
// create orphaned pointers, so be careful about your world management.
Console.ReadLine();
}
