float Cut(Mesh mesh, Transform meshTransform, Utils.Plane plane, bool triangulateHoles, bool fixPivot, bool getContourList,
out Mesh mesh0, out Mesh mesh1, out Vector3 centroid0, out Vector3 centroid1, out List<Vector3[]> contoursList)
{
var stopWatch = new Stopwatch();
stopWatch.Start();
#if PROFILING
MeasureIt.Begin("CutAllocations");
#endif
// cache mesh data
var trianglesNum = mesh.triangles.Length;
var verticesNum = mesh.vertices.Length;
var meshTriangles = mesh.triangles;
var meshVertices = mesh.vertices;
var meshNormals = mesh.normals;
var meshUV = mesh.uv;
// preallocate buffers
AllocateBuffers(trianglesNum, verticesNum);
#if PROFILING
MeasureIt.End("CutAllocations");
MeasureIt.Begin("CutCycleFirstPass");
#endif
// inverse transform cutting plane
plane.InverseTransform(meshTransform);
// first pass - find complete triangles on both sides of the plane
for (int i = 0; i < trianglesNum; i += 3)
{
// get triangle points
var v0 = meshVertices[meshTriangles[i]];
var v1 = meshVertices[meshTriangles[i + 1]];
var v2 = meshVertices[meshTriangles[i + 2]];
var side0 = plane.GetSideFix(ref v0);
var side1 = plane.GetSideFix(ref v1);
var side2 = plane.GetSideFix(ref v2);
meshVertices[meshTriangles[i]] = v0;
meshVertices[meshTriangles[i + 1]] = v1;
meshVertices[meshTriangles[i + 2]] = v2;
// all points on one side
if (side0 == side1 && side1 == side2)
{
var idx = side0 ? 0 : 1;
if (triCache[meshTriangles[i]] == 0)
{
triangles[idx].Add(triCounter[idx]);
vertices[idx].Add(meshVertices[meshTriangles[i]]);
normals[idx].Add(meshNormals[meshTriangles[i]]);
uvs[idx].Add(meshUV[meshTriangles[i]]);
centroid[idx] += meshVertices[meshTriangles[i]];
triCache[meshTriangles[i]] = triCounter[idx] + 1;
triCounter[idx]++;
}
else
{
triangles[idx].Add(triCache[meshTriangles[i]] - 1);
}
if (triCache[meshTriangles[i + 1]] == 0)
{
triangles[idx].Add(triCounter[idx]);
vertices[idx].Add(meshVertices[meshTriangles[i + 1]]);
normals[idx].Add(meshNormals[meshTriangles[i + 1]]);
uvs[idx].Add(meshUV[meshTriangles[i + 1]]);
centroid[idx] += meshVertices[meshTriangles[i + 1]];
triCache[meshTriangles[i + 1]] = triCounter[idx] + 1;
triCounter[idx]++;
}
else
{
triangles[idx].Add(triCache[meshTriangles[i + 1]] - 1);
}
if (triCache[meshTriangles[i + 2]] == 0)
{
triangles[idx].Add(triCounter[idx]);
vertices[idx].Add(meshVertices[meshTriangles[i + 2]]);
normals[idx].Add(meshNormals[meshTriangles[i + 2]]);
uvs[idx].Add(meshUV[meshTriangles[i + 2]]);
centroid[idx] += meshVertices[meshTriangles[i + 2]];
triCache[meshTriangles[i + 2]] = triCounter[idx] + 1;
triCounter[idx]++;
}
else
{
triangles[idx].Add(triCache[meshTriangles[i + 2]] - 1);
}
}
else
{
// intersection triangles add to list and process it in second pass
cutTris.Add(i);
}
}
if (vertices[0].Count == 0)
{
centroid[0] = meshVertices[0];
}
else
{
centroid[0] /= vertices[0].Count;
}
if (vertices[1].Count == 0)
{
centroid[1] = meshVertices[1];
}
else
{
centroid[1] /= vertices[1].Count;
}
#if PROFILING
MeasureIt.End("CutCycleFirstPass");
MeasureIt.Begin("CutCycleSecondPass");
#endif
AllocateContours(cutTris.Count);
// second pass - cut intersecting triangles in half
foreach (var cutTri in cutTris)
{
var triangle = new Triangle
{
ids = new[] { meshTriangles[cutTri + 0], meshTriangles[cutTri + 1], meshTriangles[cutTri + 2] },
pos = new[] { meshVertices[meshTriangles[cutTri + 0]], meshVertices[meshTriangles[cutTri + 1]], meshVertices[meshTriangles[cutTri + 2]] },
normal = new[] { meshNormals[meshTriangles[cutTri + 0]], meshNormals[meshTriangles[cutTri + 1]], meshNormals[meshTriangles[cutTri + 2]] },
uvs = new[] { meshUV[meshTriangles[cutTri + 0]], meshUV[meshTriangles[cutTri + 1]], meshUV[meshTriangles[cutTri + 2]] }
};
// check points with a plane
var side0 = plane.GetSide(triangle.pos[0]);
var side1 = plane.GetSide(triangle.pos[1]);
var side2 = plane.GetSide(triangle.pos[2]);
float t0, t1;
Vector3 s0, s1;
var idxLeft = side0 ? 0 : 1;
var idxRight = 1 - idxLeft;
if (side0 == side1)
{
var a = plane.IntersectSegment(triangle.pos[2], triangle.pos[0], out t0, out s0);
var b = plane.IntersectSegment(triangle.pos[2], triangle.pos[1], out t1, out s1);
MeshUtils.Assert(a && b, "!!!!!!!!!!!!!!!");
// left side ... 2 triangles
var s0Left = AddIntersectionPoint(s0, triangle, triangle.ids[2], triangle.ids[0], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var s1Left = AddIntersectionPoint(s1, triangle, triangle.ids[2], triangle.ids[1], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var v0Left = AddTrianglePoint(triangle.pos[0], triangle.normal[0], triangle.uvs[0], triangle.ids[0], triCache, cornerVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var v1Left = AddTrianglePoint(triangle.pos[1], triangle.normal[1], triangle.uvs[1], triangle.ids[1], triCache, cornerVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
// Triangle (s0, v0, s1)
triangles[idxLeft].Add(s0Left);
triangles[idxLeft].Add(v0Left);
triangles[idxLeft].Add(s1Left);
// Triangle (s1, v0, v1)
triangles[idxLeft].Add(s1Left);
triangles[idxLeft].Add(v0Left);
triangles[idxLeft].Add(v1Left);
// right side ... 1 triangle
var s0Right = AddIntersectionPoint(s0, triangle, triangle.ids[2], triangle.ids[0], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var s1Right = AddIntersectionPoint(s1, triangle, triangle.ids[2], triangle.ids[1], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var v2Right = AddTrianglePoint(triangle.pos[2], triangle.normal[2], triangle.uvs[2], triangle.ids[2], triCache, cornerVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
// Triangle (v2, s0, s1)
triangles[idxRight].Add(v2Right);
triangles[idxRight].Add(s0Right);
triangles[idxRight].Add(s1Right);
// buffer intersection vertices for triangulation
if (triangulateHoles)
{
if (idxLeft == 0)
{
contour.AddTriangle(cutTri, s0Left, s1Left, s0, s1);
}
else
{
contour.AddTriangle(cutTri, s0Right, s1Right, s0, s1);
}
}
}
else if (side0 == side2)
{
var a = plane.IntersectSegment(triangle.pos[1], triangle.pos[0], out t0, out s1);
var b = plane.IntersectSegment(triangle.pos[1], triangle.pos[2], out t1, out s0);
MeshUtils.Assert(a && b, "!!!!!!!!!!!!!");
// left side ... 2 triangles
var s0Left = AddIntersectionPoint(s0, triangle, triangle.ids[1], triangle.ids[2], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var s1Left = AddIntersectionPoint(s1, triangle, triangle.ids[1], triangle.ids[0], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var v0Left = AddTrianglePoint(triangle.pos[0], triangle.normal[0], triangle.uvs[0], triangle.ids[0], triCache, cornerVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var v2Left = AddTrianglePoint(triangle.pos[2], triangle.normal[2], triangle.uvs[2], triangle.ids[2], triCache, cornerVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
// Triangle (v2, s1, s0)
triangles[idxLeft].Add(v2Left);
triangles[idxLeft].Add(s1Left);
triangles[idxLeft].Add(s0Left);
// Triangle (v2, v0, s1)
triangles[idxLeft].Add(v2Left);
triangles[idxLeft].Add(v0Left);
triangles[idxLeft].Add(s1Left);
// right side ... 1 triangle
var s0Right = AddIntersectionPoint(s0, triangle, triangle.ids[1], triangle.ids[2], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var s1Right = AddIntersectionPoint(s1, triangle, triangle.ids[1], triangle.ids[0], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var v1Right = AddTrianglePoint(triangle.pos[1], triangle.normal[1], triangle.uvs[1], triangle.ids[1], triCache, cornerVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
// Triangle (s0, s1, v1)
triangles[idxRight].Add(s0Right);
triangles[idxRight].Add(s1Right);
triangles[idxRight].Add(v1Right);
// buffer intersection vertices for triangulation
if (triangulateHoles)
{
if (idxLeft == 0)
{
contour.AddTriangle(cutTri, s0Left, s1Left, s0, s1);
}
else
{
contour.AddTriangle(cutTri, s0Right, s1Right, s0, s1);
}
}
}
else
{
var a = plane.IntersectSegment(triangle.pos[0], triangle.pos[1], out t0, out s0);
var b = plane.IntersectSegment(triangle.pos[0], triangle.pos[2], out t1, out s1);
MeshUtils.Assert(a && b, "!!!!!!!!!!!!!");
// right side ... 2 triangles
var s0Right = AddIntersectionPoint(s0, triangle, triangle.ids[0], triangle.ids[1], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var s1Right = AddIntersectionPoint(s1, triangle, triangle.ids[0], triangle.ids[2], cutVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var v1Right = AddTrianglePoint(triangle.pos[1], triangle.normal[1], triangle.uvs[1], triangle.ids[1], triCache, cornerVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
var v2Right = AddTrianglePoint(triangle.pos[2], triangle.normal[2], triangle.uvs[2], triangle.ids[2], triCache, cornerVertCache[idxRight], vertices[idxRight], normals[idxRight], uvs[idxRight]);
// Triangle (v2, s1, v1)
triangles[idxRight].Add(v2Right);
triangles[idxRight].Add(s1Right);
triangles[idxRight].Add(v1Right);
// Triangle (s1, s0, v1)
triangles[idxRight].Add(s1Right);
triangles[idxRight].Add(s0Right);
triangles[idxRight].Add(v1Right);
// left side ... 1 triangle
var s0Left = AddIntersectionPoint(s0, triangle, triangle.ids[0], triangle.ids[1], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var s1Left = AddIntersectionPoint(s1, triangle, triangle.ids[0], triangle.ids[2], cutVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
var v0Left = AddTrianglePoint(triangle.pos[0], triangle.normal[0], triangle.uvs[0], triangle.ids[0], triCache, cornerVertCache[idxLeft], vertices[idxLeft], normals[idxLeft], uvs[idxLeft]);
// Triangle (s1, v0, s0)
triangles[idxLeft].Add(s1Left);
triangles[idxLeft].Add(v0Left);
triangles[idxLeft].Add(s0Left);
// buffer intersection vertices for triangulation
if (triangulateHoles)
{
if (idxLeft == 0)
{
contour.AddTriangle(cutTri, s0Left, s1Left, s0, s1);
}
else
{
contour.AddTriangle(cutTri, s0Right, s1Right, s0, s1);
}
}
}
}
#if PROFILING
MeasureIt.End("CutCycleSecondPass");
#endif
if (triangulateHoles || getContourList)
{
#if PROFILING
MeasureIt.Begin("FindContours");
#endif
contour.FindContours();
#if PROFILING
MeasureIt.End("FindContours");
#endif
}
List<int>[] trianglesCut = null;
if (triangulateHoles)
{
#if PROFILING
MeasureIt.Begin("Triangulate");
#endif
trianglesCut = new List<int>[2] { new List<int>(contour.MidPointsCount), new List<int>(contour.MidPointsCount) };
Triangulate(contour.contour, plane, vertices, normals, uvs, trianglesCut, true);
#if PROFILING
MeasureIt.End("Triangulate");
#endif
}
contoursList = null;
if (getContourList)
{
#if PROFILING
MeasureIt.Begin("GetContourList");
#endif
GetContourList(contour.contour, vertices[0], out contoursList);
#if PROFILING
MeasureIt.End("GetContourList");
#endif
}
centroid0 = centroid[0];
centroid1 = centroid[1];
if (vertices[0].Count > 0 && vertices[1].Count > 0)
{
#if PROFILING
MeasureIt.Begin("CutEndCopyBack");
#endif
mesh0 = new Mesh();
mesh1 = new Mesh();
var verticesArray0 = vertices[0].ToArray();
var verticesArray1 = vertices[1].ToArray();
#if PROFILING
MeasureIt.Begin("FixPivot");
#endif
if (fixPivot)
{
MeshUtils.CenterPivot(verticesArray0, centroid[0]);
MeshUtils.CenterPivot(verticesArray1, centroid[1]);
}
#if PROFILING
MeasureIt.End("FixPivot");
#endif
mesh0.vertices = verticesArray0;
mesh0.normals = normals[0].ToArray();
mesh0.uv = uvs[0].ToArray();
mesh1.vertices = verticesArray1;
mesh1.normals = normals[1].ToArray();
mesh1.uv = uvs[1].ToArray();
if (triangulateHoles && trianglesCut[0].Count > 0)
{
mesh0.subMeshCount = 2;
mesh0.SetTriangles(triangles[0].ToArray(), 0);
mesh0.SetTriangles(trianglesCut[0].ToArray(), 1);
mesh1.subMeshCount = 2;
mesh1.SetTriangles(triangles[1].ToArray(), 0);
mesh1.SetTriangles(trianglesCut[1].ToArray(), 1);
}
else
{
mesh0.triangles = triangles[0].ToArray();
mesh1.triangles = triangles[1].ToArray();
}
#if PROFILING
MeasureIt.End("CutEndCopyBack");
#endif
stopWatch.Stop();
return stopWatch.ElapsedMilliseconds;
}
mesh0 = null;
mesh1 = null;
stopWatch.Stop();
// UnityEngine.Debug.Log("Empty cut! " + vertices[0].Count + " " + vertices[1].Count);
return stopWatch.ElapsedMilliseconds;
}
