void Init_Bending()
{
const float s = 4;
Vector3[] x = new Vector3[]{new Vector3(-s,0,-s),
new Vector3(+s,0,-s),
new Vector3(+s,0,+s),
new Vector3(-s,0,+s)};
float[] m = new float[] { 0, 0, 0, 1 };
SoftBody psb = new SoftBody(softBodyWorldInfo, x, m);
psb.AppendLink(0, 1);
psb.AppendLink(1, 2);
psb.AppendLink(2, 3);
psb.AppendLink(3, 0);
psb.AppendLink(0, 2);
SoftWorld.AddSoftBody(psb);
}
public static SoftBody CreateFromTetGenData(SoftBodyWorldInfo worldInfo, string ele, string face, string node, bool faceLinks, bool tetraLinks, bool facesFromTetras)
{
CultureInfo culture = CultureInfo.InvariantCulture;
char[] separator = new[] { ' ' };
Vector3[] pos;
using (StringReader nodeReader = new StringReader(node))
{
string[] nodeHeader = nodeReader.ReadLine().Split(separator, StringSplitOptions.RemoveEmptyEntries);
int numNodes = int.Parse(nodeHeader[0]);
//int numDims = int.Parse(nodeHeader[1]);
//int numAttrs = int.Parse(nodeHeader[2]);
//bool hasBounds = !nodeHeader[3].Equals("0");
pos = new Vector3[numNodes];
for (int n = 0; n < numNodes; n++)
{
string[] nodeLine = nodeReader.ReadLine().Split(separator, StringSplitOptions.RemoveEmptyEntries);
pos[int.Parse(nodeLine[0])] = new Vector3(
float.Parse(nodeLine[1], culture),
float.Parse(nodeLine[2], culture),
float.Parse(nodeLine[3], culture));
}
}
SoftBody psb = new SoftBody(worldInfo, pos.Length, pos, null);
/*
if (!string.IsNullOrEmpty(face))
{
throw new NotImplementedException();
}
*/
if (!string.IsNullOrEmpty(ele))
{
using (StringReader eleReader = new StringReader(ele))
{
string[] eleHeader = eleReader.ReadLine().Split(separator, StringSplitOptions.RemoveEmptyEntries);
int numTetras = int.Parse(eleHeader[0]);
//int numCorners = int.Parse(eleHeader[1]);
//int numAttrs = int.Parse(eleHeader[2]);
for (int n = 0; n < numTetras; n++)
{
string[] eleLine = eleReader.ReadLine().Split(separator, StringSplitOptions.RemoveEmptyEntries);
//int index = int.Parse(eleLine[0], culture);
int ni0 = int.Parse(eleLine[1], culture);
int ni1 = int.Parse(eleLine[2], culture);
int ni2 = int.Parse(eleLine[3], culture);
int ni3 = int.Parse(eleLine[4], culture);
psb.AppendTetra(ni0, ni1, ni2, ni3);
if (tetraLinks)
{
psb.AppendLink(ni0, ni1, null, true);
psb.AppendLink(ni1, ni2, null, true);
psb.AppendLink(ni2, ni0, null, true);
psb.AppendLink(ni0, ni3, null, true);
psb.AppendLink(ni1, ni3, null, true);
psb.AppendLink(ni2, ni3, null, true);
}
}
}
}
//Console.WriteLine("Nodes: {0}", psb.Nodes.Count);
//Console.WriteLine("Links: {0}", psb.Links.Count);
//Console.WriteLine("Faces: {0}", psb.Faces.Count);
//Console.WriteLine("Tetras: {0}", psb.Tetras.Count);
return psb;
}
public static SoftBody CreateRope(SoftBodyWorldInfo worldInfo, Vector3 from, Vector3 to, int res, int fixeds)
{
// Create nodes
int r = res + 2;
Vector3[] x = new Vector3[r];
float[] m = new float[r];
for (int i = 0; i < r; i++)
{
Vector3.Lerp(ref from, ref to, i / (float)(r - 1), out x[i]);
m[i] = 1;
}
SoftBody psb = new SoftBody(worldInfo, r, x, m);
if ((fixeds & 1) != 0)
psb.SetMass(0, 0);
if ((fixeds & 2) != 0)
psb.SetMass(r - 1, 0);
// Create links
for (int i = 1; i < r; i++)
{
psb.AppendLink(i - 1, i);
}
return psb;
}
public static SoftBody CreatePatch(SoftBodyWorldInfo worldInfo, Vector3 corner00, Vector3 corner10, Vector3 corner01, Vector3 corner11, int resx, int resy, int fixeds, bool gendiags)
{
// Create nodes
if ((resx < 2) || (resy < 2))
return null;
int rx = resx;
int ry = resy;
int tot = rx * ry;
Vector3[] x = new Vector3[tot];
float[] m = new float[tot];
for (int iy = 0; iy < ry; iy++)
{
float ty = iy / (float)(ry - 1);
Vector3 py0, py1;
Vector3.Lerp(ref corner00, ref corner01, ty, out py0);
Vector3.Lerp(ref corner10, ref corner11, ty, out py1);
for (int ix = 0; ix < rx; ix++)
{
float tx = ix / (float)(rx - 1);
int index = rx * iy + ix;
Vector3.Lerp(ref py0, ref py1, tx, out x[index]);
m[index] = 1;
}
}
SoftBody psb = new SoftBody(worldInfo, tot, x, m);
if ((fixeds & 1) != 0)
psb.SetMass(0, 0);
if ((fixeds & 2) != 0)
psb.SetMass(rx - 1, 0);
if ((fixeds & 4) != 0)
psb.SetMass(rx * (ry - 1), 0);
if ((fixeds & 8) != 0)
psb.SetMass(rx * (ry - 1) + rx - 1, 0);
// Create links and faces
for (int iy = 0; iy < ry; ++iy)
{
for (int ix = 0; ix < rx; ++ix)
{
int ixy = rx * iy + ix;
int ix1y = ixy + 1;
int ixy1 = rx * (iy + 1) + ix;
bool mdx = (ix + 1) < rx;
bool mdy = (iy + 1) < ry;
if (mdx)
psb.AppendLink(ixy, ix1y);
if (mdy)
psb.AppendLink(ixy, ixy1);
if (mdx && mdy)
{
int ix1y1 = ixy1 + 1;
if (((ix + iy) & 1) != 0)
{
psb.AppendFace(ixy, ix1y, ix1y1);
psb.AppendFace(ixy, ix1y1, ixy1);
if (gendiags)
{
psb.AppendLink(ixy, ix1y1);
}
}
else
{
psb.AppendFace(ixy1, ixy, ix1y);
psb.AppendFace(ixy1, ix1y, ix1y1);
if (gendiags)
{
psb.AppendLink(ix1y, ixy1);
}
}
}
}
}
return psb;
}
public static SoftBody CreateFromTriMesh(SoftBodyWorldInfo worldInfo, Vector3[] vertices, int[] triangles, bool randomizeConstraints = true)
{
int numTriangleIndices = triangles.Length;
int numTriangles = numTriangleIndices / 3;
int maxIndex = 0; // triangles.Max() + 1;
for (int i = 0; i < numTriangleIndices; i++)
{
if (triangles[i] > maxIndex)
{
maxIndex = triangles[i];
}
}
maxIndex++;
SoftBody psb = new SoftBody(worldInfo, maxIndex, vertices, null);
BitArray chks = new BitArray(maxIndex * maxIndex);
for (int i = 0; i < numTriangleIndices; i += 3)
{
int[] idx = new int[] { triangles[i], triangles[i + 1], triangles[i + 2] };
for (int j = 2, k = 0; k < 3; j = k++)
{
int chkIndex = maxIndex * idx[k] + idx[j];
if (!chks[chkIndex])
{
chks[chkIndex] = true;
chks[maxIndex * idx[j] + idx[k]] = true;
psb.AppendLink(idx[j], idx[k]);
}
}
psb.AppendFace(idx[0], idx[1], idx[2]);
}
if (randomizeConstraints)
{
psb.RandomizeConstraints();
}
return psb;
}
// Helper to test and add links correctly.
// Records links that have already been generated
static bool TestAndAddLink(AlignedIntArray trianglesForLinks, SoftBody softBody, int triangle, IntArray triangleVertexIndexArray, int numVertices, int vertex0, int vertex1, int nonLinkVertex, Material structuralMaterial, bool createBendLinks, Material bendMaterial)
{
if (trianglesForLinks[numVertices * vertex0 + vertex1] >= 0 && createBendLinks)
{
// Already have link so find other triangle and generate cross link
int otherTriangle = trianglesForLinks[numVertices * vertex0 + vertex1];
int[] otherIndices = new int[] { triangleVertexIndexArray[otherTriangle * 3], triangleVertexIndexArray[otherTriangle * 3 + 1], triangleVertexIndexArray[otherTriangle * 3 + 2] };
int nodeA = 0;
// Test all links of the other triangle against this link. The one that's not part of it is what we want.
if (otherIndices[0] != vertex0 && otherIndices[0] != vertex1)
nodeA = otherIndices[0];
if (otherIndices[1] != vertex0 && otherIndices[1] != vertex1)
nodeA = otherIndices[1];
if (otherIndices[2] != vertex0 && otherIndices[2] != vertex1)
nodeA = otherIndices[2];
softBody.AppendLink(nodeA, nonLinkVertex, bendMaterial);
}
else
{
// Don't yet have link so create it
softBody.AppendLink(vertex0, vertex1, structuralMaterial);
// If we added a new link, set the triangle array
trianglesForLinks[numVertices * vertex0 + vertex1] = triangle;
trianglesForLinks[numVertices * vertex1 + vertex0] = triangle;
}
return true;
}
