/// <summary>
/// Create a verlet cluster.
/// </summary>
/// <param name="world">Verlet world</param>
/// <param name="centerPosition">Center position</param>
/// <param name="pointCount">Point count</param>
/// <param name="diameter">Cluster diameter</param>
/// <param name="gravityScale">Gravity scale</param>
/// <param name="tearSensitivityFactor">Distance factor required to break the cloth. Use `-1` to create an unbreakable cloth.</param>
/// <param name="stiffness">Stiffness of the cloth</param>
/// <param name="drawPoints">Draw points</param>
/// <param name="pointRadius">Verlet point radius</param>
public VerletCluster(VerletWorld world, Vector2 centerPosition, int pointCount, float diameter, float gravityScale = 1, float tearSensitivityFactor = -1, float stiffness = 0.1f, bool drawPoints = true, float pointRadius = 10f)
{
Points = new List <VerletPoint>();
for (int i = 0; i < pointCount; ++i)
{
var position = centerPosition + new Vector2((float)GD.RandRange(-1, 1), (float)GD.RandRange(-1, 1));
var point = world.CreatePoint();
point.GravityScale = gravityScale;
point.Radius = pointRadius;
point.Visible = drawPoints;
point.MoveToPosition(position);
Points.Add(point);
}
for (int i = 0; i < Points.Count - 1; ++i)
{
for (int j = i + 1; j < Points.Count; ++j)
{
var a = Points[i];
var b = Points[j];
var link = world.CreateLink(a, b);
link.RestingDistance = diameter;
link.TearSensitivity = diameter * tearSensitivityFactor;
link.Stiffness = stiffness;
}
}
}
/// <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>
/// Add chain point at a specific position.
/// </summary>
/// <param name="position">Position vector</param>
/// <param name="configurator">Point configurator</param>
/// <returns>Builder</returns>
public VerletChainBuilder AddPointAtPosition(Vector2 position, PointConfiguratorFunc configurator = null)
{
var point = world.CreatePoint();
point.MoveToPosition(position);
if (points.Count == 0 && pinFirst)
{
point.PinToCurrentPosition();
}
else if (!drawIntermediatePoints)
{
point.Visible = false;
}
configurator?.Invoke(point);
points.Add(point);
return(this);
}
/// <summary>
/// Create a verlet cloth.
/// </summary>
/// <param name="world">Verlet world</param>
/// <param name="topLeftPosition">Top-left position</param>
/// <param name="pointCount">X/Y point count</param>
/// <param name="separation">Separation</param>
/// <param name="pinMode">Pin mode</param>
/// <param name="tearSensitivityFactor">Distance factor required to break the cloth. Use `-1` to create an unbreakable cloth.</param>
/// <param name="stiffness">Stiffness of the cloth</param>
/// <param name="drawPoints">Draw verlet points</param>
/// <param name="pointRadius">Verlet point radius</param>
public VerletCloth(VerletWorld world, Vector2 topLeftPosition, Vector2 pointCount, float separation, PinModeEnum pinMode = PinModeEnum.TopCorners, float tearSensitivityFactor = 2, float stiffness = 1, bool drawPoints = false, float pointRadius = 10f)
{
points = new List <VerletPoint>();
for (int j = 0; j < pointCount.y; ++j)
{
for (int i = 0; i < pointCount.x; ++i)
{
var position = topLeftPosition + new Vector2(separation * i, separation * j);
var point = world.CreatePoint();
point.Radius = pointRadius;
point.Visible = drawPoints;
point.MoveToPosition(position);
if (pinMode == PinModeEnum.AllCorners)
{
if ((j == 0 || j == pointCount.y - 1) && (i == 0 || i == pointCount.x - 1))
{
point.PinToCurrentPosition();
}
}
else if (pinMode == PinModeEnum.TopCorners)
{
if (j == 0 && (i == 0 || i == pointCount.x - 1))
{
point.PinToCurrentPosition();
}
}
else if (pinMode == PinModeEnum.Top)
{
if (j == 0)
{
point.PinToCurrentPosition();
}
}
points.Add(point);
}
}
if (points.Count == 0)
{
GD.PrintErr("Bad points length for cloth. Need to be > 0");
return;
}
for (int j = 0; j < pointCount.y; ++j)
{
for (int i = 0; i < pointCount.x; ++i)
{
if (i > 0)
{
// Right to left
int pAIdx = i - 1 + (j * (int)pointCount.x);
int pBIdx = i + (j * (int)pointCount.x);
var link = world.CreateLink(points[pAIdx], points[pBIdx]);
link.RestingDistance = separation;
link.TearSensitivity = separation * tearSensitivityFactor;
link.Stiffness = stiffness;
}
if (j > 0)
{
// Bottom to top
int pAIdx = i + ((j - 1) * (int)pointCount.x);
int pBIdx = i + (j * (int)pointCount.x);
var link = world.CreateLink(points[pAIdx], points[pBIdx]);
link.RestingDistance = separation;
link.TearSensitivity = separation * tearSensitivityFactor;
link.Stiffness = stiffness;
}
}
}
}