private static void Capping(Plane blade, MeshCutSide leftSide, MeshCutSide rightSide, List <Vector3> newVertices)
{
try
{
List <Vector3> capVertTracker = new List <Vector3>();
List <Vector3> capVertpolygon = new List <Vector3>();
int numNewVertices = newVertices.Count;
for (int i = 0; i < numNewVertices; i++)
{
if (!capVertTracker.Contains(newVertices[i]))
{
capVertpolygon.Clear();
capVertpolygon.Add(newVertices[i]);
capVertpolygon.Add(newVertices[i + 1]);
capVertTracker.Add(newVertices[i]);
capVertTracker.Add(newVertices[i + 1]);
bool isDone = false;
while (!isDone)
{
isDone = true;
for (int k = 0; k < numNewVertices; k += 2)
{
// go through the pairs
if (newVertices[k] == capVertpolygon[capVertpolygon.Count - 1] && !capVertTracker.Contains(newVertices[k + 1]))
{
// if so add the other
isDone = false;
capVertpolygon.Add(newVertices[k + 1]);
capVertTracker.Add(newVertices[k + 1]);
}
else if (newVertices[k + 1] == capVertpolygon[capVertpolygon.Count - 1] && !capVertTracker.Contains(newVertices[k]))
{
// if so add the other
isDone = false;
capVertpolygon.Add(newVertices[k]);
capVertTracker.Add(newVertices[k]);
}
}
}
FillCap(blade, leftSide, rightSide, capVertpolygon);
}
}
}
catch (System.Exception e)
{
Debug.LogErrorFormat("MeshCutter Capping: Caught exception: {0}", e.Message);
}
}
static void FillCap(Plane blade, MeshCutSide leftSide, MeshCutSide rightSide, List <Vector3> vertices)
{
// center of the cap
Vector3 center = Vector3.zero;
int numVertices = vertices.Count;
for (int i = 0; i < numVertices; ++i)
{
center += vertices[i];
}
center = center / vertices.Count;
// you need an axis based on the cap
Vector3 upward = Vector3.zero;
// 90 degree turn
upward.x = blade.normal.y;
upward.y = -blade.normal.x;
upward.z = blade.normal.z;
Vector3 left = Vector3.Cross(blade.normal, upward);
Vector3 displacement = Vector3.zero;
Vector3 newUV1 = Vector3.zero;
Vector3 newUV2 = Vector3.zero;
Vector2 half = new Vector2(0.5f, 0.5f);
for (int i = 0; i < numVertices; ++i)
{
displacement = vertices[i] - center;
newUV1 = Vector3.zero;
newUV1.x = 0.5f + Vector3.Dot(displacement, left);
newUV1.y = 0.5f + Vector3.Dot(displacement, upward);
newUV1.z = 0.5f + Vector3.Dot(displacement, blade.normal);
displacement = vertices[(i + 1) % vertices.Count] - center;
newUV2 = Vector3.zero;
newUV2.x = 0.5f + Vector3.Dot(displacement, left);
newUV2.y = 0.5f + Vector3.Dot(displacement, upward);
newUV2.z = 0.5f + Vector3.Dot(displacement, blade.normal);
leftSide.AddTriangle(
new Vector3[] {
vertices[i], vertices[(i + 1) % vertices.Count], center
},
new Vector3[] {
-blade.normal, -blade.normal, -blade.normal
},
new Vector2[] {
newUV1, newUV2, half
},
-blade.normal,
leftSide.subIndices.Count - 1
);
rightSide.AddTriangle(
new Vector3[] {
vertices[i], vertices[(i + 1) % vertices.Count], center
},
new Vector3[] {
blade.normal, blade.normal, blade.normal
},
new Vector2[] {
newUV1, newUV2, half
},
blade.normal,
rightSide.subIndices.Count - 1
);
}
}
private static void CutFace(
Plane blade,
MeshCutSide leftSide,
MeshCutSide rightSide,
List <Vector3> newVertices,
Vector3[] targetMeshVertices,
Vector3[] targetMeshNormals,
Vector2[] targetMeshUVs,
int submesh,
bool[] sides,
int index1,
int index2,
int index3)
{
Vector3[] leftPoints = new Vector3[2];
Vector3[] leftNormals = new Vector3[2];
Vector2[] leftUvs = new Vector2[2];
Vector3[] rightPoints = new Vector3[2];
Vector3[] rightNormals = new Vector3[2];
Vector2[] rightUvs = new Vector2[2];
bool didset_left = false;
bool didset_right = false;
int p = index1;
for (int side = 0; side < 3; side++)
{
switch (side)
{
case 0: p = index1; break;
case 1: p = index2; break;
case 2: p = index3; break;
}
if (sides[side])
{
if (!didset_left)
{
didset_left = true;
leftPoints[0] = targetMeshVertices[p];
leftPoints[1] = leftPoints[0];
leftUvs[0] = targetMeshUVs[p];
leftUvs[1] = leftUvs[0];
leftNormals[0] = targetMeshNormals[p];
leftNormals[1] = leftNormals[0];
}
else
{
leftPoints[1] = targetMeshVertices[p];
leftUvs[1] = targetMeshUVs[p];
leftNormals[1] = targetMeshNormals[p];
}
}
else
{
if (!didset_right)
{
didset_right = true;
rightPoints[0] = targetMeshVertices[p];
rightPoints[1] = rightPoints[0];
rightUvs[0] = targetMeshUVs[p];
rightUvs[1] = rightUvs[0];
rightNormals[0] = targetMeshNormals[p];
rightNormals[1] = rightNormals[0];
}
else
{
rightPoints[1] = targetMeshVertices[p];
rightUvs[1] = targetMeshUVs[p];
rightNormals[1] = targetMeshNormals[p];
}
}
}
float normalizedDistance = 0.0f;
float distance = 0;
blade.Raycast(new Ray(leftPoints[0], (rightPoints[0] - leftPoints[0]).normalized), out distance);
normalizedDistance = distance / (rightPoints[0] - leftPoints[0]).magnitude;
Vector3 newVertex1 = Vector3.Lerp(leftPoints[0], rightPoints[0], normalizedDistance);
Vector2 newUv1 = Vector2.Lerp(leftUvs[0], rightUvs[0], normalizedDistance);
Vector3 newNormal1 = Vector3.Lerp(leftNormals[0], rightNormals[0], normalizedDistance);
newVertices.Add(newVertex1);
blade.Raycast(new Ray(leftPoints[1], (rightPoints[1] - leftPoints[1]).normalized), out distance);
normalizedDistance = distance / (rightPoints[1] - leftPoints[1]).magnitude;
Vector3 newVertex2 = Vector3.Lerp(leftPoints[1], rightPoints[1], normalizedDistance);
Vector2 newUv2 = Vector2.Lerp(leftUvs[1], rightUvs[1], normalizedDistance);
Vector3 newNormal2 = Vector3.Lerp(leftNormals[1], rightNormals[1], normalizedDistance);
newVertices.Add(newVertex2);
leftSide.AddTriangle(new Vector3[] { leftPoints[0], newVertex1, newVertex2 },
new Vector3[] { leftNormals[0], newNormal1, newNormal2 },
new Vector2[] { leftUvs[0], newUv1, newUv2 }, newNormal1,
submesh);
leftSide.AddTriangle(new Vector3[] { leftPoints[0], leftPoints[1], newVertex2 },
new Vector3[] { leftNormals[0], leftNormals[1], newNormal2 },
new Vector2[] { leftUvs[0], leftUvs[1], newUv2 }, newNormal2,
submesh);
rightSide.AddTriangle(new Vector3[] { rightPoints[0], newVertex1, newVertex2 },
new Vector3[] { rightNormals[0], newNormal1, newNormal2 },
new Vector2[] { rightUvs[0], newUv1, newUv2 }, newNormal1,
submesh);
rightSide.AddTriangle(new Vector3[] { rightPoints[0], rightPoints[1], newVertex2 },
new Vector3[] { rightNormals[0], rightNormals[1], newNormal2 },
new Vector2[] { rightUvs[0], rightUvs[1], newUv2 }, newNormal2,
submesh);
}
/// <summary>
/// Cuts the specified target into two pieces and caps the sides with the specified Material.
/// </summary>
/// <param name="target">The target that is cut - must have a MeshFilter component.</param>
/// <param name="anchorPoint">Anchor point of the blade i.e. the point where the blade cuts the object.</param>
/// <param name="normalDirection">Normal direction of the blade plane.</param>
/// <param name="capMaterial">Cap material - placed as material on the cutting surface of the two sides.</param>
/// <param name="copyRigidbody">Should the rigidbody be copied to both of the two new pieces.</param>
/// <param name="copyRigidbody">Should both of the new pieces have colliders.</param>
public static IObservable <GameObject[]> Cut(GameObject target, Vector3 anchorPoint, Vector3 normalDirection, Material capMaterial, bool copyRigidbody = true, bool copyCollider = true)
{
// Set the blade relative to victim
Plane blade = new Plane(target.transform.InverseTransformDirection(-normalDirection),
target.transform.InverseTransformPoint(anchorPoint));
// Get the target mesh
Mesh targetMesh = target.GetComponent <MeshFilter>().mesh;
Vector3[] targetMeshVertices = targetMesh.vertices;
Vector3[] targetMeshNormals = targetMesh.normals;
Vector2[] targetMeshUVs = targetMesh.uv;
int subMeshCount = targetMesh.subMeshCount;
List <int[]> subMeshIndices = new List <int[]>();
for (int i = 0; i < subMeshCount; ++i)
{
subMeshIndices.Add(targetMesh.GetIndices(i));
}
// Material parameters
Material[] mats = target.GetComponent <MeshRenderer>().sharedMaterials;
string[] matsNames = mats.Select(m => m.name).ToArray();
string capMaterialName = capMaterial.name;
return(Observable.Start(() =>
{
if (targetMesh == null)
{
Debug.LogError("MeshCut Cut: Target did not have a MeshFilter component");
}
// Left and right side mesh cuts
MeshCutSide leftSide = new MeshCutSide(targetMeshVertices, targetMeshNormals, targetMeshUVs);
MeshCutSide rightSide = new MeshCutSide(targetMeshVertices, targetMeshNormals, targetMeshUVs);
// New vertices for capping the cutting surface
List <Vector3> newVertices = new List <Vector3>();
bool[] sides = new bool[3];
int p1, p2, p3;
for (int sub = 0; sub < subMeshCount; ++sub)
{
int[] indices = subMeshIndices[sub];
leftSide.subIndices.Add(new List <int>());
rightSide.subIndices.Add(new List <int>());
for (int i = 0; i < indices.Length; i += 3)
{
p1 = indices[i];
p2 = indices[i + 1];
p3 = indices[i + 2];
sides[0] = blade.GetSide(targetMeshVertices[p1]);
sides[1] = blade.GetSide(targetMeshVertices[p2]);
sides[2] = blade.GetSide(targetMeshVertices[p3]);
// whole triangle
if (sides[0] == sides[1] && sides[0] == sides[2])
{
if (sides[0])
{
// left side
leftSide.AddTriangle(p1, p2, p3, sub);
}
else
{
rightSide.AddTriangle(p1, p2, p3, sub);
}
}
else
{
// Cut the triangle
CutFace(
blade,
leftSide,
rightSide,
newVertices,
targetMeshVertices,
targetMeshNormals,
targetMeshUVs,
sub,
sides,
p1,
p2,
p3
);
}
}
}
if (matsNames[mats.Length - 1] != capMaterialName)
{
// Add cap indices
leftSide.subIndices.Add(new List <int>());
rightSide.subIndices.Add(new List <int>());
Material[] newMats = new Material[mats.Length + 1];
mats.CopyTo(newMats, 0);
newMats[mats.Length] = capMaterial;
mats = newMats;
}
// Cap the openings
Capping(blade, leftSide, rightSide, newVertices);
return new MeshCutSide[] { leftSide, rightSide };
},
Scheduler.ThreadPool)
.ObserveOnMainThread()
.Select(results => {
MeshCutSide leftSide = results[0];
MeshCutSide rightSide = results[1];
// Left Mesh
Mesh leftHalfMesh = new Mesh();
leftHalfMesh.name = "Split Mesh Left";
leftHalfMesh.vertices = leftSide.vertices.ToArray();
leftHalfMesh.triangles = leftSide.triangles.ToArray();
leftHalfMesh.normals = leftSide.normals.ToArray();
leftHalfMesh.uv = leftSide.uvs.ToArray();
leftHalfMesh.subMeshCount = leftSide.subIndices.Count;
int leftHalfMeshSubMeshCount = leftHalfMesh.subMeshCount;
for (int i = 0; i < leftHalfMeshSubMeshCount; ++i)
{
leftHalfMesh.SetIndices(leftSide.subIndices[i].ToArray(), MeshTopology.Triangles, i);
}
// Right Mesh
Mesh rightHalfMesh = new Mesh();
rightHalfMesh.name = "Split Mesh Right";
rightHalfMesh.vertices = rightSide.vertices.ToArray();
rightHalfMesh.triangles = rightSide.triangles.ToArray();
rightHalfMesh.normals = rightSide.normals.ToArray();
rightHalfMesh.uv = rightSide.uvs.ToArray();
rightHalfMesh.subMeshCount = rightSide.subIndices.Count;
int rightHalfSubMeshCount = rightHalfMesh.subMeshCount;
for (int i = 0; i < rightHalfSubMeshCount; ++i)
{
rightHalfMesh.SetIndices(rightSide.subIndices[i].ToArray(), MeshTopology.Triangles, i);
}
// Assign the game objects
target.GetComponent <MeshFilter>().mesh = leftHalfMesh;
GameObject leftSideObj = target;
GameObject rightSideObj = new GameObject(target.name, typeof(MeshFilter), typeof(MeshRenderer));
rightSideObj.transform.position = target.transform.position;
rightSideObj.transform.rotation = target.transform.rotation;
rightSideObj.transform.localScale = target.transform.localScale;
rightSideObj.GetComponent <MeshFilter>().mesh = rightHalfMesh;
// Maintain colliders and rigidbodies on both pieces i.e. populate the right piece
Rigidbody leftSideRigidbody = leftSideObj.GetComponent <Rigidbody>();
MeshCollider leftSideCollider = leftSideObj.GetComponent <MeshCollider>();
if (copyRigidbody && leftSideRigidbody != null)
{
Rigidbody rigidbody = rightSideObj.AddComponent <Rigidbody>();
rigidbody.useGravity = leftSideRigidbody.useGravity;
rigidbody.interpolation = leftSideRigidbody.interpolation;
rigidbody.collisionDetectionMode = leftSideRigidbody.collisionDetectionMode;
}
if (copyCollider && leftSideCollider != null)
{
MeshCollider meshCollider = rightSideObj.AddComponent <MeshCollider>();
meshCollider.convex = true;
}
// Assign mats
leftSideObj.GetComponent <MeshRenderer>().materials = mats;
rightSideObj.GetComponent <MeshRenderer>().materials = mats;
return new GameObject[] { leftSideObj, rightSideObj };
}));
}
