public MovingJoint()
{
var capeFixture = new FixtureDef(new PolygonShape(0.08f, 0.4f, (float)(Math.PI)), 0.2f);
var capeBody = new BodyDef(BodyType.Dynamic, new Vec2(0, 10));
Body testbody = m_world.CreateBody(capeBody);
testbody.CreateFixture(capeFixture);
staticBody = m_world.CreateBody(new BodyDef(BodyType.Static, testbody.WorldCenter + new Vec2(-0.08f / 25, 0.4f)));
staticBody.CreateFixture(new CircleShape(0.15f), 0);
{
RevoluteJointDef rjd = new RevoluteJointDef();
rjd.Initialize(testbody, staticBody, testbody.WorldCenter + new Vec2(0.0f, 0.4f));
joint = (RevoluteJoint)m_world.CreateJoint(rjd);
}
// build cape
Body lastBody = testbody;
for (int i = 0; i < 8; ++i)
{
capeBody.Position = new Vec2(capeBody.Position.X, capeBody.Position.Y - 0.8f);
var nextBody = m_world.CreateBody(capeBody);
nextBody.CreateFixture(capeFixture);
var joint = new RevoluteJointDef();
joint.Initialize(lastBody, nextBody, nextBody.WorldCenter + new Vec2(0.0f, 0.4f));
m_world.CreateJoint(joint);
lastBody = nextBody;
}
}
/// Initialize the bodies, anchors, and reference angle using a world
/// anchor point.
public void Initialize(Body body1, Body body2, Vec2 anchor)
{
BodyA = body1;
BodyB = body2;
_localAnchorA = BodyA.GetLocalPoint(anchor);
_localAnchorB = BodyB.GetLocalPoint(anchor);
_referenceAngle = BodyB.Angle - BodyA.Angle;
}
public Fixture[] AddToBody(Body body, float density)
{
Fixture[] fixtures = new Fixture[_shapes.Count];
for (int i = 0; i < _shapes.Count; ++i)
fixtures[i] = body.CreateFixture(_shapes[i], density);
return fixtures;
}
/// Main...
public ElasticBody()
{
Program.MainForm.ViewZoom = 0.25f;
/// Bottom static body
{
PolygonShape sd = new PolygonShape();
sd.SetAsBox(50.0f, 2.0f);
BodyDef bd = new BodyDef();
bd.Position = new Vec2(-1.0f, -7.5f);
m_ground = m_world.CreateBody(bd);
m_ground.CreateFixture(new FixtureDef(sd, 0.0f, 0.1f, 0.1f));
}
/// "Elastic body" 64 bodies - something like a lin. elastic compound
/// connected via dynamic forces (springs)
{
PolygonShape sd = new PolygonShape();
sd.SetAsBox(width, height);
FixtureDef sdf = new FixtureDef();
sdf.Density = 1.5f;
sdf.Friction = 0.01f;
sdf.Filter.GroupIndex = -1;
sdf.Shape = sd;
Vec2 startpoint = new Vec2(0, 0);
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Bullet = false;
//bd.AllowSleep = false;
for (int i = 0; i < BodyCountY; ++i)
{
for (int j = 0; j < BodyCountX; ++j)
{
bd.Position = new Vec2(j*(width*2), 2.51f + (height*2) * i);
bd.Position += startpoint;
Body body = m_world.CreateBody(bd);
bodies[BodyCountX*i+j] = body;
body.CreateFixture(sdf);
}
}
}
}
public Body[] GenerateBodies(World world, Vec2 basePosition, FixtureDef def)
{
if (_vecs.Count <= 1)
throw new ArgumentOutOfRangeException("Vecs");
Body[] bodies = new Body[_vecs.Count - 1];
for (int i = 0; i < _vecs.Count - 1; ++i)
{
PolygonShape edge = new PolygonShape(_vecs[i], _vecs[i + 1]);
BodyDef bd = new BodyDef();
bd.Position = basePosition;
bodies[i] = world.CreateBody(bd);
bodies[i].CreateFixture(new FixtureDef(edge, 0, def.Restitution, def.Friction, false, def.UserData));
}
return bodies;
}
public ShapeEditing()
{
{
BodyDef bd = new BodyDef();
Body ground = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsEdge(new Vec2(-40.0f, 0.0f), new Vec2(40.0f, 0.0f));
ground.CreateFixture(shape, 0.0f);
}
{
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(0.0f, 10.0f);
m_body = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsBox(4.0f, 4.0f, new Vec2(0.0f, 0.0f), 0.0f);
m_fixture1 = m_body.CreateFixture(shape, 10.0f);
m_fixture2 = null;
}
}
public TitleState(StateStack stack, Context context)
: base(stack, context)
{
starttimer = new Clock();
starttimer.Restart();
titletext = new Text();
titletext.Scale = new Vector2f(2, 2);
titletext.DisplayedString = "PIXELTASIM";
titletext.Font = mContext.mFonts.get(FontID.Title);
titletext.centerOrigin();
titletext.Position = new Vector2f(mContext.mWindow.Size.X/2, mContext.mWindow.Size.Y / 8);
titletext.Color = Color.Black;
square = new RectangleShape(new Vector2f(UnitConverter.toPixScale(0.5f), UnitConverter.toPixScale(0.5f)));
square.centerOrigin();
square.FillColor = Color.Red;
square.OutlineColor = Color.Black;
square.OutlineThickness = 1;
b2World = new World(new Vec2(0, 10), false);
BodyDef b2Def = new BodyDef();
b2Def.BodyType = BodyType.Dynamic;
b2Def.Position = new Vec2(UnitConverter.toSimScale(mContext.mWindow.Size.X / 2), UnitConverter.toSimScale(mContext.mWindow.Size.Y / 8*3));
b2Body = b2World.CreateBody(b2Def);
PolygonShape dynamicbox = new PolygonShape();
dynamicbox.SetAsBox(UnitConverter.toSimScale(32), UnitConverter.toSimScale(32));
FixtureDef fixDef = new FixtureDef();
fixDef.Shape = dynamicbox;
fixDef.Density = 1;
fixDef.Friction = 0.3f;
b2Body.CreateFixture(fixDef);
square.Position = new Vector2f(UnitConverter.toPixScale(b2Body.Position.X), UnitConverter.toPixScale(b2Body.Position.Y));
}
public Car()
{
{ // car body
PolygonShape poly1 = new PolygonShape(), poly2 = new PolygonShape();
// bottom half
poly1.Vertices = new Vec2[]
{
new Vec2(2.2f,-0.74f),
new Vec2(2.2f,-0.2f),
new Vec2(1.0f,0),
new Vec2(-2.2f,0),
new Vec2(-2.2f,-0.74f)
};
FixtureDef fixture1 = new FixtureDef();
fixture1.Filter.GroupIndex = -1;
fixture1.Shape = poly1;
fixture1.Density = 20.0f;
fixture1.Friction = 0.68f;
// top half
poly2.Vertices = new Vec2[]
{
new Vec2(1.0f,0),
new Vec2(0.5f,0.74f),
new Vec2(-1.3f,0.7f),
new Vec2(-1.7f,0),
};
FixtureDef fixture2 = new FixtureDef();
fixture2.Filter.GroupIndex = -1;
fixture2.Shape = poly2;
fixture2.Density = 5.0f;
fixture2.Friction = 0.68f;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(0, 0);
m_vehicle = m_world.CreateBody(bd);
m_vehicle.CreateFixture(fixture1);
m_vehicle.CreateFixture(fixture2);
}
{ // vehicle wheels
CircleShape circ = new CircleShape();
circ.Radius = 0.58608f;
FixtureDef wheelFix = new FixtureDef();
wheelFix.Shape = circ;
wheelFix.Density = 40.0f;
wheelFix.Friction = 0.8f;
wheelFix.Filter.GroupIndex = -1;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.AllowSleep = false;
bd.Position = new Vec2(1.2f, -0.8f);
m_rightWheel = m_world.CreateBody(bd);
m_rightWheel.CreateFixture(wheelFix);
bd.Position = new Vec2(-1.2f, -0.8f);
m_leftWheel = m_world.CreateBody(bd);
m_leftWheel.CreateFixture(wheelFix);
}
{ // join wheels to chassis
RevoluteJointDef jd = new RevoluteJointDef();
jd.Initialize(m_vehicle, m_leftWheel, m_leftWheel.WorldCenter);
jd.CollideConnected = false;
jd.EnableMotor = true;
jd.MaxMotorTorque = 10.0f;
jd.MotorSpeed = 0.0f;
m_leftJoint = (RevoluteJoint)m_world.CreateJoint(jd);
jd.Initialize(m_vehicle, m_rightWheel, m_rightWheel.WorldCenter);
jd.CollideConnected = false;
m_rightJoint = (RevoluteJoint)m_world.CreateJoint(jd);
}
}
public BodyTypes()
{
Body ground = null;
{
BodyDef bd = new BodyDef();
ground = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsEdge(new Vec2(-20.0f, 0.0f), new Vec2(20.0f, 0.0f));
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
ground.CreateFixture(fd);
}
// Define attachment
{
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(0.0f, 3.0f);
m_attachment = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.5f, 2.0f);
m_attachment.CreateFixture(shape, 2.0f);
}
// Define platform
{
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(-4.0f, 5.0f);
m_platform = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.5f, 4.0f, new Vec2(4.0f, 0.0f), 0.5f * (float)Math.PI);
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
fd.Friction = 0.6f;
fd.Density = 2.0f;
m_platform.CreateFixture(fd);
RevoluteJointDef rjd = new RevoluteJointDef();
rjd.Initialize(m_attachment, m_platform, new Vec2(0.0f, 5.0f));
rjd.MaxMotorTorque = 50.0f;
rjd.EnableMotor = true;
m_world.CreateJoint(rjd);
PrismaticJointDef pjd = new PrismaticJointDef();
pjd.Initialize(ground, m_platform, new Vec2(0.0f, 5.0f), new Vec2(1.0f, 0.0f));
pjd.MaxMotorForce = 1000.0f;
pjd.EnableMotor = true;
pjd.LowerTranslation = -10.0f;
pjd.UpperTranslation = 10.0f;
pjd.EnableLimit = true;
m_world.CreateJoint(pjd);
m_speed = 3.0f;
}
// Create a payload
{
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(0.0f, 8.0f);
m_payload = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.75f, 0.75f);
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
fd.Friction = 0.6f;
fd.Density = 2.0f;
m_payload.CreateFixture(fd);
}
}
public void Initialize(Body bodyA, Body bodyB, Vec2 anchor)
{
BodyA = bodyA;
BodyB = bodyB;
_localAnchorA = bodyA.GetLocalPoint(anchor);
_localAnchorB = bodyB.GetLocalPoint(anchor);
_referenceAngle = bodyB.Angle - bodyA.Angle;
}
public Test()
{
Vec2 gravity;
gravity = new Vec2(0.0f, -10.0f);
bool doSleep = true;
m_world = new World(gravity, doSleep);
m_bomb = null;
m_textLine = 30;
m_mouseJoint = null;
m_pointCount = 0;
m_destructionListener.test = this;
m_world.DestructionListener = m_destructionListener;
m_world.ContactListener = this;
m_world.DebugDraw = m_debugDraw;
m_bombSpawning = false;
m_stepCount = 0;
BodyDef bodyDef = new BodyDef();
m_groundBody = m_world.CreateBody(bodyDef);
m_groundBody.UserData = "Ground";
}
public void LaunchBomb(Vec2 position, Vec2 velocity)
{
if (m_bomb != null)
{
m_world.DestroyBody(m_bomb);
m_bomb = null;
}
m_bomb = m_world.CreateBody(new BodyDef(BodyType.Dynamic, position, 0.0f, velocity, true));
m_bomb.Mass = 5;
m_bomb.CreateFixture(new FixtureDef(new CircleShape(0.3f), 20.0f));
}
public Bridge()
{
Body ground = null;
{
BodyDef bd = new BodyDef();
ground = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsEdge(new Vec2(-40.0f, 0.0f), new Vec2(40.0f, 0.0f));
ground.CreateFixture(shape, 0.0f);
}
{
PolygonShape shape = new PolygonShape();
shape.SetAsBox(0.5f, 0.125f);
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
fd.Density = 20.0f;
fd.Friction = 0.2f;
RevoluteJointDef jd = new RevoluteJointDef();
Body prevBody = ground;
for (int i = 0; i < e_count; ++i)
{
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(-14.5f + 1.0f * i, 5.0f);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
Vec2 anchor = new Vec2(-15.0f + 1.0f * i, 5.0f);
jd.Initialize(prevBody, body, anchor);
m_world.CreateJoint(jd);
if (i == (e_count >> 1))
m_middle = body;
prevBody = body;
}
jd.Initialize(prevBody, ground, new Vec2(-15.0f + 1.0f * e_count, 5.0f));
m_world.CreateJoint(jd);
}
for (int i = 0; i < 2; ++i)
{
Vec2[] vertices = new Vec2[3];
vertices[0] = new Vec2(-0.5f, 0.0f);
vertices[1] = new Vec2(0.5f, 0.0f);
vertices[2] = new Vec2(0.0f, 1.5f);
PolygonShape shape = new PolygonShape();
shape.Vertices = vertices;
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
fd.Density = 1.0f;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(-8.0f + 8.0f * i, 12.0f);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
}
for (int i = 0; i < 3; ++i)
{
CircleShape shape = new CircleShape();
shape.Radius = 0.5f;
FixtureDef fd = new FixtureDef();
fd.Shape = shape;
fd.Density = 1.0f;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(-6.0f + 6.0f * i, 10.0f);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
}
}
public TheoJansen()
{
m_offset = new Vec2(0.0f, 8.0f);
m_motorSpeed = 2.0f;
m_motorOn = true;
Vec2 pivot = new Vec2(0.0f, 0.8f);
// Ground
{
BodyDef bd = new BodyDef();
Body ground = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
shape.SetAsEdge(new Vec2(-50.0f, 0.0f), new Vec2(50.0f, 0.0f));
ground.CreateFixture(shape, 0.0f);
shape.SetAsEdge(new Vec2(-50.0f, 0.0f), new Vec2(-50.0f, 10.0f));
ground.CreateFixture(shape, 0.0f);
shape.SetAsEdge(new Vec2(50.0f, 0.0f), new Vec2(50.0f, 10.0f));
ground.CreateFixture(shape, 0.0f);
const float groundHeight = 0.19f;
const float groundHeight2 = groundHeight * 2;
shape.SetAsBox(10, groundHeight, new Vec2(-14, (groundHeight / 2)), 0);
ground.CreateFixture(shape, 0.0f);
shape.SetAsBox(8, groundHeight, new Vec2(-14, (groundHeight / 2) + groundHeight2), 0);
ground.CreateFixture(shape, 0.0f);
shape.SetAsBox(6, groundHeight, new Vec2(-14, (groundHeight / 2) + groundHeight2 + groundHeight2), 0);
ground.CreateFixture(shape, 0.0f);
shape.SetAsBox(4, groundHeight, new Vec2(-14, (groundHeight / 2) + groundHeight2 + groundHeight2 + groundHeight2), 0);
ground.CreateFixture(shape, 0.0f);
shape.SetAsBox(2, groundHeight, new Vec2(-14, (groundHeight / 2) + groundHeight2 + groundHeight2 + groundHeight2 + groundHeight2), 0);
ground.CreateFixture(shape, 0.0f);
}
// Balls
for (int i = 0; i < 25; ++i)
{
CircleShape shape = new CircleShape();
shape.Radius = 0.25f;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(-40.0f + 2.0f * i, 3f);
Body body = m_world.CreateBody(bd);
body.CreateFixture(shape, 1.0f);
}
// Chassis
{
PolygonShape shape = new PolygonShape();
shape.SetAsBox(2.5f, 1.0f);
FixtureDef sd = new FixtureDef();
sd.Density = 1.0f;
sd.Shape = shape;
sd.Filter.GroupIndex = -1;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = pivot + m_offset;
m_chassis = m_world.CreateBody(bd);
m_chassis.CreateFixture(sd);
}
{
CircleShape shape = new CircleShape();
shape.Radius = 1.6f;
FixtureDef sd = new FixtureDef();
sd.Density = 1.0f;
sd.Shape = shape;
sd.Filter.GroupIndex = -1;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.Position = pivot + m_offset;
m_wheel = m_world.CreateBody(bd);
m_wheel.CreateFixture(sd);
}
{
RevoluteJointDef jd = new RevoluteJointDef();
jd.Initialize(m_wheel, m_chassis, pivot + m_offset);
jd.CollideConnected = false;
jd.MotorSpeed = m_motorSpeed;
jd.MaxMotorTorque = 400.0f;
jd.EnableMotor = m_motorOn;
m_motorJoint = (RevoluteJoint)m_world.CreateJoint(jd);
}
Vec2 wheelAnchor = pivot + new Vec2(0.0f, -0.8f);
CreateLeg(-1.0f, wheelAnchor);
CreateLeg(1.0f, wheelAnchor);
m_wheel.SetTransform(m_wheel.Position, 120.0f * (float)Math.PI / 180.0f);
CreateLeg(-1.0f, wheelAnchor);
CreateLeg(1.0f, wheelAnchor);
m_wheel.SetTransform(m_wheel.Position, -120.0f * (float)Math.PI / 180.0f);
CreateLeg(-1.0f, wheelAnchor);
CreateLeg(1.0f, wheelAnchor);
}
/// Initialize the bodies, anchors, axis, and reference angle using the world
/// anchor and world axis.
public void Initialize(Body bodyA, Body bodyB, Vec2 anchor, Vec2 axis)
{
BodyA = bodyA;
BodyB = bodyB;
_localAnchorA = bodyA.GetLocalPoint(anchor);
_localAnchorB = bodyB.GetLocalPoint(anchor);
_localAxisA = bodyA.GetLocalVector(axis);
}
/// Initialize the bodies, anchors, lengths, max lengths, and ratio using the world anchors.
public void Initialize(Body bodyA, Body bodyB,
Vec2 groundAnchorA, Vec2 groundAnchorB,
Vec2 anchorA, Vec2 anchorB,
float ratio)
{
BodyA = bodyA;
BodyB = bodyB;
_groundAnchorA = groundAnchorA;
_groundAnchorB = groundAnchorB;
_localAnchorA = bodyA.GetLocalPoint(anchorA);
_localAnchorB = bodyB.GetLocalPoint(anchorB);
Vec2 d1 = anchorA - groundAnchorA;
_lengthA = d1.Length();
Vec2 d2 = anchorB - groundAnchorB;
_lengthB = d2.Length();
_ratio = ratio;
if (!(ratio > float.Epsilon))
throw new ArgumentException("Ratio is too small");
float C = _lengthA + ratio * _lengthB;
_maxLengthA = C - ratio * b2_minPulleyLength;
_maxLengthB = (C - b2_minPulleyLength) / ratio;
}
public void DestroyBody(Body body)
{
NativeMethods.b2world_destroybody(_worldPtr, body.BodyPtr);
}
/// Add a spring force
void AddSpringForce(Body bA, Vec2 localA, Body bB, Vec2 localB, float k, float friction, float desiredDist)
{
Vec2 pA = bA.GetWorldPoint(localA);
Vec2 pB = bB.GetWorldPoint(localB);
Vec2 diff = pB - pA;
//Find velocities of attach points
Vec2 vA = bA.LinearVelocity - (bA.GetWorldVector(localA).Cross(bA.AngularVelocity));
Vec2 vB = bB.LinearVelocity - (bB.GetWorldVector(localB).Cross(bB.AngularVelocity));
Vec2 vdiff = vB-vA;
float dx = diff.Normalize(); //normalizes diff and puts length into dx
float vrel = vdiff.X*diff.X + vdiff.Y*diff.Y;
float forceMag = -k*(dx-desiredDist) - friction*vrel;
diff *= forceMag; // diff *= forceMag
bB.ApplyForce(diff, bA.GetWorldPoint(localA));
diff *= -1.0f;
bA.ApplyForce(diff, bB.GetWorldPoint(localB));
}
/// Initialize the bodies, anchors, and length using the world
/// anchors.
public void Initialize(Body bodyA, Body bodyB,
Vec2 anchorA, Vec2 anchorB)
{
BodyA = bodyA;
BodyB = bodyB;
_localAnchorA = bodyA.GetLocalPoint(anchorA);
_localAnchorB = bodyB.GetLocalPoint(anchorB);
Vec2 d = anchorB - anchorA;
_length = d.Length();
}
public ApplyForce()
{
m_world.Gravity = new Vec2(0.0f, 0.0f);
const float k_restitution = 0.4f;
Body ground;
{
BodyDef bd = new BodyDef();
bd.Position = new Vec2(0.0f, 20.0f);
ground = m_world.CreateBody(bd);
PolygonShape shape = new PolygonShape();
FixtureDef sd = new FixtureDef();
sd.Shape = shape;
sd.Density = 0.0f;
sd.Restitution = k_restitution;
// Left vertical
shape.SetAsEdge(new Vec2(-20.0f, -20.0f), new Vec2(-20.0f, 20.0f));
ground.CreateFixture(sd);
// Right vertical
shape.SetAsEdge(new Vec2(20.0f, -20.0f), new Vec2(20.0f, 20.0f));
ground.CreateFixture(sd);
// Top horizontal
shape.SetAsEdge(new Vec2(-20.0f, 20.0f), new Vec2(20.0f, 20.0f));
ground.CreateFixture(sd);
// Bottom horizontal
shape.SetAsEdge(new Vec2(-20.0f, -20.0f), new Vec2(20.0f, -20.0f));
ground.CreateFixture(sd);
}
{
Transform xf1 = new Transform();
xf1.R = new Mat22(0.3524f * (float)Math.PI);
xf1.Position = (xf1.R * new Vec2(1.0f, 0.0f));
Vec2[] vertices = new Vec2[3]
{
(xf1 * new Vec2(-1.0f, 0.0f)),
(xf1 * new Vec2(1.0f, 0.0f)),
(xf1 * new Vec2(0.0f, 0.5f))
};
PolygonShape poly1 = new PolygonShape(vertices);
FixtureDef sd1 = new FixtureDef();
sd1.Shape = poly1;
sd1.Density = 4.0f;
Transform xf2 = new Transform();
xf2.R = new Mat22(-0.3524f * (float)Math.PI);
xf2.Position = (xf2.R * new Vec2(-1.0f, 0.0f));
vertices = new Vec2[]
{
(xf2 * new Vec2(-1.0f, 0.0f)),
(xf2 * new Vec2(1.0f, 0.0f)),
(xf2 * new Vec2(0.0f, 0.5f))
};
PolygonShape poly2 = new PolygonShape(vertices);
FixtureDef sd2 = new FixtureDef();
sd2.Shape = poly2;
sd2.Density = 2.0f;
BodyDef bd = new BodyDef();
bd.BodyType = BodyType.Dynamic;
bd.AngularDamping = 5.0f;
bd.LinearDamping = 0.1f;
bd.Position = new Vec2(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.BodyType = BodyType.Dynamic;
bd.Position = new Vec2(0.0f, 5.0f + 1.54f * i);
Body body = m_world.CreateBody(bd);
body.CreateFixture(fd);
float gravity = 10.0f;
float I = body.Inertia;
float mass = body.Mass;
// 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 = jd.LocalAnchorB = Vec2.Empty;
jd.BodyA = ground;
jd.BodyB = body;
jd.CollideConnected = true;
jd.MaxForce = mass * gravity;
jd.MaxTorque = mass * radius * gravity;
m_world.CreateJoint(jd);
}
}
}
