private void Update()
{
if (Input.GetMouseButtonDown(0))
{
if (!_isDone)
{
_poly.Add(GetMousePoint());
}
}
if (Input.GetMouseButtonDown(1))
{
if (!_isDone)
{
_hole.Add(GetMousePoint());
}
}
if (Input.GetKeyDown(KeyCode.Return) || Input.GetKeyDown(KeyCode.KeypadEnter))
{
if (_poly.Count >= 3 && _hole.Count >= 3)
{
_isDone = true;
_full = Triangulator.RemoveHoles(_poly, _hole);
_tris = Triangulator.TriangulatePolygon(_full, new Vector3(0f, 0f, -1f));
}
}
if (Input.GetKeyDown(KeyCode.T))
{
showTris = !showTris;
}
if (Input.GetKeyDown(KeyCode.C) && (Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)))
{
_isDone = false;
_poly.Clear();
_hole.Clear();
if (_tris != null)
{
_tris.Clear();
}
}
}
public static bool SliceMultiTriangleMesh(GameObject meshGO, Vector3 cutStartPos, Vector3 cutEndPos,
Material material, bool makePiecesDrop = true, bool log = true)
{
// TODO: it might make sense to check in advance somehow if anything is going to be affected
// by the cut, even if we don't actually do anything if it's not.
var cutNormal = CalculateCutNormal(cutStartPos, cutEndPos, log);
staticCutNormal = cutNormal;
var meshTransform = meshGO.transform;
TransformCutToObjectSpace(ref cutStartPos, ref cutEndPos, ref cutNormal, meshTransform);
var mesh = meshGO.GetComponent <MeshFilter>().sharedMesh;
var vertsAboveCut = new List <Vector3>();
var normalsAboveCut = new List <Vector3>();
var vertsBelowCut = new List <Vector3>();
var normalsBelowCut = new List <Vector3>();
var atLeastOneTriangleWasCut = false;
var meshVertices = mesh.vertices;
var meshTriangles = mesh.triangles;
var meshNormals = mesh.normals;
//TODO - how long will it be? Can we pre-calc?
var cutEdges = new List <Edge>();
for (int triStartIndex = 0; triStartIndex < meshTriangles.Length; triStartIndex += 3)
{
var intersection = CalculateIntersections(meshVertices, meshTriangles, meshNormals, triStartIndex,
cutStartPos, cutNormal, log);
if (intersection.type == CutType.None)
{
if (IsTriAboveCut(meshVertices, meshTriangles, triStartIndex, cutStartPos, cutNormal, log))
{
CopyVertsAndNormals(meshVertices, meshTriangles, meshNormals, triStartIndex, vertsAboveCut, normalsAboveCut);
}
else
{
CopyVertsAndNormals(meshVertices, meshTriangles, meshNormals, triStartIndex, vertsBelowCut, normalsBelowCut);
}
}
else
{
atLeastOneTriangleWasCut = true;
CutTriangleAndCopyVertsAndNormals(mesh, intersection, cutStartPos, cutNormal,
vertsAboveCut, normalsAboveCut,
vertsBelowCut, normalsBelowCut,
cutEdges, log);
}
}
// Create cut surfaces
// So what should happen:
// cutFacePolys = ConnectEdges(cutEdges).
// if more than one polygon found:
// - collect "is a hole in" relationships
// - iter through and remove all the holes
// now do the thing.
if (atLeastOneTriangleWasCut)
{
var cutFacePolys = ConnectEdges(cutEdges);
var isHole = new bool[cutFacePolys.Count];
if (cutFacePolys.Count > 1)
{
var holes = FindHolesIn(cutFacePolys);
foreach (var hole in holes)
{
cutFacePolys[hole.outerPolyIndex] = Triangulator.RemoveHoles(cutFacePolys[hole.outerPolyIndex],
cutFacePolys[hole.holePolyIndex]);
isHole[hole.holePolyIndex] = true;
}
}
var foundAtLeastOneFace = false;
for (int polyIndex = 0; polyIndex < cutFacePolys.Count; ++polyIndex)
{
if (!isHole[polyIndex] && cutFacePolys[polyIndex].Count > 2)
{
var face = Triangulator.TriangulatePolygon(cutFacePolys[polyIndex], -cutNormal);
var triCount = face.Count;
if (triCount > 0 && triCount % 3 == 0)
{
foundAtLeastOneFace = true;
for (int i = triCount - 1; i >= 0; --i)
{
vertsBelowCut.Add(face[i]);
normalsAboveCut.Add(-cutNormal);
normalsBelowCut.Add(cutNormal);
}
vertsAboveCut.AddRange(face);
}
}
}
if (!foundAtLeastOneFace)
{
return(false);
}
}
if (atLeastOneTriangleWasCut)
{
var meshAbove = BuildMesh(vertsAboveCut, normalsAboveCut, log);
var meshBelow = BuildMesh(vertsBelowCut, normalsBelowCut, log);
var goAbove = BuildGO(meshAbove, string.Format("{0}_above", meshGO.name), meshTransform, material, cutNormal, true, makePiecesDrop, log);
var goBelow = BuildGO(meshBelow, string.Format("{0}_below", meshGO.name), meshTransform, material, cutNormal, false, makePiecesDrop, log);
}
return(atLeastOneTriangleWasCut);
}
