public void ApplyBehavior(VerletPoint point, float delta)
{
if (!point.Touched)
{
point.ApplyForce(Gravity * point.GravityScale);
}
}
/// <summary>
/// Create a verlet link.
/// </summary>
/// <param name="a">First verlet point</param>
/// <param name="b">First verlet point</param>
/// <param name="restingDistance">Resting distance</param>
/// <param name="minimalDistance">Minimal link distance. Use `-1` to disable.</param>
/// <param name="maximalDistance">Maximal link distance. Use `-1` to disable.</param>
/// <param name="tearSensitivity">Distance required to break the link. Use `-1` to create an unbreakable link.</param>
/// <param name="tearSensitivityFactor">Distance factor required to break the link. Use `-1` to create an unbreakable link.</param>
/// <param name="stiffness">Stiffness of the link</param>
/// <param name="width">Width of the link</param>
/// <param name="color">Link color</param>
/// <param name="visible">Show link</param>
/// <returns>Verlet link</returns>
public VerletLink CreateLink(
VerletPoint a,
VerletPoint b,
float?restingDistance = null,
float?minimalDistance = null,
float?maximalDistance = null,
float?tearSensitivity = null,
float?tearSensitivityFactor = null,
float?stiffness = null,
float?width = null,
Color?color = null,
bool?visible = null)
{
var link = new VerletLink(this, a, b);
a.AddLink(link);
AddChild(link);
link.Visible = visible ?? link.Visible;
link.RestingDistance = restingDistance ?? link.RestingDistance;
link.MinimalDistance = minimalDistance ?? link.MinimalDistance;
link.MaximalDistance = maximalDistance ?? link.MaximalDistance;
link.TearSensitivity = tearSensitivity ?? link.TearSensitivity;
link.Stiffness = stiffness ?? link.Stiffness;
link.Modulate = color ?? link.Modulate;
link.Width = width ?? link.Width;
if (tearSensitivityFactor.HasValue)
{
link.TearSensitivity = link.RestingDistance * tearSensitivityFactor.Value;
}
return(link);
}
/// <summary>
/// Create a verlet ragdoll.
/// </summary>
/// <param name="world">Verlet world</param>
/// <param name="centerPosition">Center position</param>
/// <param name="height">Body height</param>
/// <param name="gravityScale">Gravity scale</param>
/// <param name="tearSensitivityFactor">Distance factor required to break links. Use '-1' to create an unbreakable ragdoll</param>
/// <param name="pointRadius">Point radius</param>
/// <param name="drawIntermediatePoints">Draw all ragdoll points</param>
/// <param name="drawSupportLinks">Draw support links</param>
public VerletRagdoll(VerletWorld world, Vector2 centerPosition, float height, float gravityScale = 1, float tearSensitivityFactor = -1, float pointRadius = 10f, bool drawIntermediatePoints = false, bool drawSupportLinks = false)
{
Vector2 genPos()
{
return(centerPosition + MathUtils.RandVector2(-5, 5, -5, 5));
}
VerletPoint createPoint(float mass, float?radius = null, bool?visible = null)
{
var point = world.CreatePoint(genPos(), mass: mass, radius: radius ?? pointRadius, visible: visible ?? drawIntermediatePoints);
point.GravityScale = gravityScale;
return(point);
}
var headSize = pointRadius * 3;
var handSize = pointRadius * 2;
var footSize = pointRadius * 1.5f;
var headLength = height / 7.5f;
head = createPoint(4, radius: headSize, visible: true);
shoulder = createPoint(26);
world.CreateLink(head, shoulder, restingDistance: 5 / 4 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
elbowLeft = createPoint(2);
elbowRight = createPoint(2);
world.CreateLink(elbowLeft, shoulder, restingDistance: 3 / 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
world.CreateLink(elbowRight, shoulder, restingDistance: 3 / 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
handLeft = createPoint(2, radius: handSize, visible: true);
handRight = createPoint(2, radius: handSize, visible: true);
world.CreateLink(handLeft, elbowLeft, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
world.CreateLink(handRight, elbowRight, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
pelvis = createPoint(15);
world.CreateLink(pelvis, shoulder, restingDistance: 3.5f * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 0.8f);
world.CreateLink(pelvis, head, restingDistance: 4.75f * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 0.02f, visible: drawSupportLinks, color: Colors.LightBlue.WithAlpha(64));
kneeLeft = createPoint(10);
kneeRight = createPoint(10);
world.CreateLink(kneeLeft, pelvis, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
world.CreateLink(kneeRight, pelvis, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
footLeft = createPoint(20, radius: footSize, visible: true);
footRight = createPoint(20, radius: footSize, visible: true);
world.CreateLink(footLeft, kneeLeft, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
world.CreateLink(footRight, kneeRight, restingDistance: 2 * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 1);
world.CreateLink(footLeft, shoulder, restingDistance: 7.5f * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 0.001f, visible: drawSupportLinks, color: Colors.LightBlue.WithAlpha(64));
world.CreateLink(footRight, shoulder, restingDistance: 7.5f * headLength, tearSensitivityFactor: tearSensitivityFactor, stiffness: 0.001f, visible: drawSupportLinks, color: Colors.LightBlue.WithAlpha(64));
}
/// <summary>
/// Create a simple verlet link.
/// </summary>
/// <param name="world">World</param>
/// <param name="a">Point A</param>
/// <param name="b">Point B</param>
public VerletLink(VerletWorld world, VerletPoint a, VerletPoint b)
{
A = a;
B = b;
this.world = world;
PositionA = A.GlobalPosition;
PositionB = B.GlobalPosition;
if (RestingDistance == 0)
{
// Calculate resting distance from points position
RestingDistance = (PositionB - PositionA).Length();
}
}
/// <summary>
/// Create a verlet point.
/// </summary>
/// <param name="initialPosition">Initial position</param>
/// <param name="mass">Mass</param>
/// <param name="gravityScale">Gravity scale</param>
/// <param name="radius">Radius</param>
/// <param name="color">Color</param>
/// <param name="visible">Show point</param>
/// <returns>Verlet point</returns>
public VerletPoint CreatePoint(Vector2?initialPosition = null, float?mass = null, float?gravityScale = null, float?radius = null, Color?color = null, bool?visible = null)
{
var point = new VerletPoint(this);
points.Add(point);
AddChild(point);
point.Mass = mass ?? point.Mass;
point.GravityScale = gravityScale ?? point.GravityScale;
point.Radius = radius ?? point.Radius;
point.Visible = visible ?? point.Visible;
point.Modulate = color ?? point.Modulate;
if (initialPosition.HasValue)
{
point.MoveToPosition(initialPosition.Value);
}
return(point);
}
