/// <summary>
/// Computes a convex shape description for a TransformableShape and applies it.
/// </summary>
public void UpdateConvexShapeInfo()
{
//Compute the volume distribution.
var samples = CommonResources.GetVectorList();
if (samples.Capacity < InertiaHelper.SampleDirections.Length)
{
samples.Capacity = InertiaHelper.SampleDirections.Length;
}
samples.Count = InertiaHelper.SampleDirections.Length;
for (int i = 0; i < InertiaHelper.SampleDirections.Length; ++i)
{
shape.GetLocalExtremePointWithoutMargin(ref InertiaHelper.SampleDirections[i], out samples.Elements[i]);
}
var triangles = CommonResources.GetIntList();
ConvexHullHelper.GetConvexHull(samples, triangles);
float volume;
InertiaHelper.ComputeShapeDistribution(samples, triangles, out volume, out volumeDistribution);
Volume = volume;
//Estimate the minimum radius based on the surface mesh.
MinimumRadius = InertiaHelper.ComputeMinimumRadius(samples, triangles, ref Toolbox.ZeroVector) + collisionMargin;
MaximumRadius = ComputeMaximumRadius();
CommonResources.GiveBack(samples);
CommonResources.GiveBack(triangles);
}
/// <summary>
/// Computes a convex shape description for a ConvexHullShape.
/// </summary>
/// <param name="vertices">Vertices describing the convex hull shape.</param>
/// <param name="collisionMargin">Collision margin of the shape.</param>
/// <param name="center">Computed center of the convex hull shape. Used as the origin of the outputUniqueSurfaceVertices.</param>
/// <param name="outputHullTriangleIndices">Computed list of indices into the input point set composing the triangulated surface of the convex hull.
/// Each group of 3 indices represents a triangle on the surface of the hull.</param>
/// <param name="outputUniqueSurfaceVertices">Computed nonredundant list of vertices composing the outer shell of the input point set. Recentered on the local origin.</param>
/// <returns>Description required to define a convex shape.</returns>
public static ConvexShapeDescription ComputeDescription(IList <Vector3> vertices, float collisionMargin, out Vector3 center, IList <int> outputHullTriangleIndices, IList <Vector3> outputUniqueSurfaceVertices)
{
if (outputHullTriangleIndices.Count != 0 || outputUniqueSurfaceVertices.Count != 0)
{
throw new ArgumentException("Output lists must start empty.");
}
ConvexShapeDescription description;
ConvexHullHelper.GetConvexHull(vertices, outputHullTriangleIndices, outputUniqueSurfaceVertices);
InertiaHelper.ComputeShapeDistribution(vertices, outputHullTriangleIndices, out center, out description.EntityShapeVolume.Volume, out description.EntityShapeVolume.VolumeDistribution);
//Recenter the surface vertices.
for (int i = 0; i < outputUniqueSurfaceVertices.Count; ++i)
{
outputUniqueSurfaceVertices[i] -= center;
}
description.MinimumRadius = InertiaHelper.ComputeMinimumRadius(vertices, outputHullTriangleIndices, ref center) + collisionMargin;
description.MaximumRadius = ComputeMaximumRadius(outputUniqueSurfaceVertices, collisionMargin);
description.CollisionMargin = collisionMargin;
return(description);
}