private int TraverseCut(Cut cut, EdgeLoop loop, List <Vertex> perimeter, int currentVertexIndex)
{
cut.traversed = true;
// add all vertices of the egress's cut to the loop
loop.vertices.AddRange(cut);
perimeter[currentVertexIndex].loops.Add(loop);
// find the index of the last vertex in the cut (which is always an egress) and get its index in the perimeter
currentVertexIndex = perimeter.IndexOf(cut[cut.Count - 1]);
perimeter[currentVertexIndex].loops.Add(loop);
string cutString = "";
foreach (Vertex vertex in cut)
{
cutString += " ";
if (perimeter.Contains(vertex))
{
cutString += perimeter.IndexOf(vertex) + ": ";
}
cutString += vertex;
}
//Debug.Log("Traversing egress: " + cutString);
//Debug.Log("Egress traversed. Arrived at " + currentVertexIndex);
return(currentVertexIndex);
}
private List <Triangle> TriangulateEdgeLoop(EdgeLoop loop, bool debug = false)
{
List <Triangle> triangles = new List <Triangle>();
for (int i = 1; i < loop.vertices.Count - 1; i++)
{
triangles.Add(new Triangle(loop.vertices[0], loop.vertices[i], loop.vertices[(i + 1) % loop.vertices.Count]));
}
return(triangles);
}
public bool LiesWithinLoop(EdgeLoop loop)
{
//Debug.Log("kjshfd");
// collect intersection points
Vector3 castDirection = (loop.vertices[0].value - loop.vertices[1].value).normalized;
List <Vector3> positiveIntersections = new List <Vector3>();
List <Vector3> negativeIntersections = new List <Vector3>();
for (int i = 0; i < loop.vertices.Count; i++)
{
Point3 intersection = IntersectLineWithEdge(
this.value,
castDirection,
loop.vertices[i].value,
loop.vertices[(i + 1) % loop.vertices.Count].value);
if (intersection != null)
{
Vector3 directionToIntersection = (intersection.value - this.value).normalized;
//Debug.Log("found intersection");
if (Vector3.Dot(directionToIntersection, castDirection) == 1)
{
positiveIntersections.Add(intersection.value);
}
else
{
negativeIntersections.Add(intersection.value);
}
}
}
// remove duplicates
RemoveDuplicates(positiveIntersections);
RemoveDuplicates(negativeIntersections);
// count # above, below
// if both odd, return true, else return false
return(positiveIntersections.Count % 2 == 1 && negativeIntersections.Count % 2 == 1);
}
private EdgeLoop DiscoverInternalLoop(Vertex initialVertex, List <Vertex> unusedVertices, List <EdgeLoop> loops)
{
//TODO: discovery of loops
Queue <EdgeLoop> potentialLoops = new Queue <EdgeLoop>();
List <EdgeLoop> completedLoops = new List <EdgeLoop>();
potentialLoops.Enqueue(new EdgeLoop());
potentialLoops.Peek().vertices.Add(initialVertex);
int k = 0;
Debug.Log("before");
while (potentialLoops.Count > 0)
{
Debug.Log("as");
Vertex nextVertex;
do
{
nextVertex = null;
// foundNext = false;
//Debug.Log(potentialLoops.Count);
List <Vertex> loopVertices = potentialLoops.Peek().vertices;
for (int i = unusedVertices.Count - 1; i >= 0; i--)
{
if (unusedVertices[i].SharesTriangle(loopVertices[loopVertices.Count - 1]) &&
!loopVertices.Contains(unusedVertices[i]))
{
if (nextVertex == null)
{
Debug.Log("found next in path");
nextVertex = unusedVertices[i];
}
else
{
Debug.Log("found additional possible path");
EdgeLoop newLoop = new EdgeLoop(potentialLoops.Peek().vertices);
//Debug.Log(newLoop.vertices);
potentialLoops.Enqueue(newLoop);
foreach (EdgeLoop vertex in potentialLoops)
{
//Debug.Log(vertex);
}
}
k++;
if (k > 100)
{
throw new System.Exception();
}
//unusedVertices.RemoveAt(i);
//initialVertex = unusedVertices[i];
//foundNext = true;
}
}
if (nextVertex != null)
{
Debug.Log(nextVertex.value);
loopVertices.Add(nextVertex);
Debug.Log(loopVertices.Count);
Debug.Log(potentialLoops.Peek().vertices.Count);
}
} while (nextVertex != null);
completedLoops.Add(potentialLoops.Dequeue());
}
// Debug.Log(potentialLoops.Peek().vertices.Count);
// the loop with the greatest number of vertices is the correct loop
EdgeLoop finalLoop = completedLoops[0];
foreach (EdgeLoop loop in completedLoops)
{
if (loop.vertices.Count > finalLoop.vertices.Count)
{
finalLoop = loop;
}
}
Debug.Log(finalLoop.vertices.Count);
// determine which external loop contains this new loop
foreach (EdgeLoop loop in loops)
{
if (initialVertex.LiesWithinLoop(loop))
{
if (loop.nestedLoop == null)
{
loop.nestedLoop = finalLoop;
}
else
{
finalLoop.nestedLoop = loop.nestedLoop;
EdgeLoop previousLoop = loop;
do
{
if (initialVertex.LiesWithinLoop(finalLoop.nestedLoop))
{
previousLoop.nestedLoop = finalLoop.nestedLoop;
finalLoop.nestedLoop = finalLoop.nestedLoop.nestedLoop;
previousLoop.nestedLoop.nestedLoop = finalLoop;
}
else
{
break;
}
} while (finalLoop.nestedLoop != null);
}
// we've found the loop we're contained by, break out
break;
}
}
return(finalLoop);
}
// classify existing verticies
// perform new cut operation on each face of the bounded shape
// add back to mesh
public Mesh ClipAToB(GameObject toClip, GameObject bounds, GameObject result, bool flipNormals = false)
{
//Debug.Log("hello");
// get a list of all triangles of the bounding mesh
List <Triangle> boundsTriangles = GetBoundsTriangles(toClip, bounds);
// get a list of all vertices of the clipping target
List <Vertex> vertices = ClassifyVertices(toClip, bounds, boundsTriangles);
// get a list of all triangles of the clipping target
List <Triangle> meshTriangles = GetAllTriangles(toClip, vertices);
// here is where the final triangles will be stored
List <Triangle> triangles = new List <Triangle>();
// to create the triangles, we'll need a list of edge loops to triangluate
List <EdgeLoop> edgeLoops = new List <EdgeLoop>();
//TODO: this is debug code that I need for now
// fill the edge loops that need to be filled, add the result to the list of triangles
if (triangleCount > -1 && triangleCount < meshTriangles.Count)
{
edgeLoops.AddRange(ClipTriangleToBound(meshTriangles[triangleCount], boundsTriangles, vertices, true));
foreach (EdgeLoop loop in edgeLoops)
{
if (loop.filled)
{
triangles.AddRange(TriangulateEdgeLoop(loop));
}
EdgeLoop nestedLoop = loop.nestedLoop;
while (nestedLoop != null)
{
if (nestedLoop.filled)
{
triangles.AddRange(TriangulateEdgeLoop(nestedLoop));
}
nestedLoop = nestedLoop.nestedLoop;
}
}
}
else if (triangleCount < meshTriangles.Count)
{
foreach (Triangle triangle in meshTriangles)
{
edgeLoops.AddRange(ClipTriangleToBound(triangle, boundsTriangles, vertices));
}
foreach (EdgeLoop loop in edgeLoops)
{
if (loop.filled)
{
triangles.AddRange(TriangulateEdgeLoop(loop));
}
EdgeLoop nestedLoop = loop.nestedLoop;
while (nestedLoop != null)
{
if (nestedLoop.filled)
{
triangles.AddRange(TriangulateEdgeLoop(nestedLoop));
}
nestedLoop = nestedLoop.nestedLoop;
}
}
}
else
{
return(null);
}
if (flipNormals)
{
foreach (Triangle triangle in triangles)
{
triangle.FlipNormal();
}
}
Mesh completedMesh = new Mesh();
result.GetComponent <MeshFilter>().mesh = completedMesh;
// reindex vertices and add them to the mesh
List <Vector3> createdVertices = new List <Vector3>();
// add vertices to mesh
for (int i = 0; i < vertices.Count; i++)
{
vertices[i].index = i;
createdVertices.Add(vertices[i].value);
}
completedMesh.SetVertices(createdVertices);
// add triangles to mesh
int[] newTriangles = new int[triangles.Count * 3];
int index = 0;
foreach (Triangle triangle in triangles)
{
foreach (Vertex vertex in triangle.vertices)
{
if (!vertices.Contains(vertex))
{
Debug.Log("Vertex " + vertex + " not contained in vertices, :: " + vertex.containedByBound);
}
}
}
//Debug.Log(triangles.Count);
foreach (Triangle triangle in triangles)
{
newTriangles[index] = triangle.vertices[0].index;
index++;
newTriangles[index] = triangle.vertices[1].index;
index++;
newTriangles[index] = triangle.vertices[2].index;
index++;
}
completedMesh.SetTriangles(newTriangles, 0);
completedMesh.RecalculateTangents();
completedMesh.RecalculateNormals();
return(completedMesh);
}
private List <EdgeLoop> ClipTriangleToBound(Triangle triangle, List <Triangle> boundsTriangles, List <Vertex> vertices, bool debug = false)
{
List <Egress> aToBEgresses = new List <Egress>();
List <Egress> bToCEgresses = new List <Egress>();
List <Egress> cToAEgresses = new List <Egress>();
List <Vertex> internalIntersections = new List <Vertex>();
// find all intersections between the triangle and the bound
foreach (Triangle boundsTriangle in boundsTriangles)
{
IntersectTriangleEdge(triangle.vertices[0].value, triangle.vertices[1].value, aToBEgresses, boundsTriangle, debug);
IntersectTriangleEdge(triangle.vertices[1].value, triangle.vertices[2].value, bToCEgresses, boundsTriangle, debug);
IntersectTriangleEdge(triangle.vertices[2].value, triangle.vertices[0].value, cToAEgresses, boundsTriangle, debug);
internalIntersections.AddRange(FindTriangleIntersections(boundsTriangle, triangle));
if (debug)
{
foreach (Vertex intersection in internalIntersections)
{
Debug.DrawRay(transform.localToWorldMatrix.MultiplyPoint3x4(intersection.value), Vector3.back * 0.1f, Color.green, Time.deltaTime);
}
}
}
if (debug)
{
foreach (Vertex vertex in triangle.vertices)
{
Color color = Color.blue;
if (vertex.containedByBound)
{
color = Color.cyan;
}
Debug.DrawRay(transform.localToWorldMatrix.MultiplyPoint3x4(vertex.value), Vector3.back * 0.1f, color, Time.deltaTime);
}
}
List <Egress> allEgresses = new List <Egress>();
allEgresses.AddRange(aToBEgresses);
allEgresses.AddRange(bToCEgresses);
allEgresses.AddRange(cToAEgresses);
// combine duplicate internal intersections
for (int i = internalIntersections.Count - 1; i > 0; i--)
{
for (int k = i - 1; k >= 0; k--)
{
if (Vector3.Distance(internalIntersections[i].value, internalIntersections[k].value) < intersectionError)
{
internalIntersections[k].triangles.AddRange(internalIntersections[i].triangles);
internalIntersections.RemoveAt(i);
break;
}
}
}
// store the resulting intersections in the greater vertex list
vertices.AddRange(aToBEgresses);
vertices.AddRange(bToCEgresses);
vertices.AddRange(cToAEgresses);
vertices.AddRange(internalIntersections);
// organize the intersections into cuts
CreateCuts(allEgresses, internalIntersections);
//TODO: soon. deal with floating islands by collecting up loops without egresses
// (they won't be a part of any cuts)
// organize all triangle vertices and egress intersections in an ordered list around the perimeter
List <Vertex> perimeter = new List <Vertex>();
aToBEgresses.Sort((a, b) => (int)Mathf.Sign(Vector3.Distance(a.value, triangle.vertices[0].value) - Vector3.Distance(b.value, triangle.vertices[0].value)));
bToCEgresses.Sort((a, b) => (int)Mathf.Sign(Vector3.Distance(a.value, triangle.vertices[1].value) - Vector3.Distance(b.value, triangle.vertices[1].value)));
cToAEgresses.Sort((a, b) => (int)Mathf.Sign(Vector3.Distance(a.value, triangle.vertices[2].value) - Vector3.Distance(b.value, triangle.vertices[2].value)));
perimeter.Add(triangle.vertices[0]);
perimeter.AddRange(aToBEgresses);
perimeter.Add(triangle.vertices[1]);
perimeter.AddRange(bToCEgresses);
perimeter.Add(triangle.vertices[2]);
perimeter.AddRange(cToAEgresses);
perimeter.Add(triangle.vertices[0]);// a duplicate of the first vertex as a sentinel
// find all edge loops and classify whether they should be retopologized or not
List <EdgeLoop> loops = new List <EdgeLoop>();
// while there are still entries in that list for which we haven't identified all loops (1 for triangle vertices, 2 for egresses)
//Debug.Log("Beginning classification of edge loops");
foreach (Vertex vertex in triangle.vertices)
{
vertex.loops = new List <EdgeLoop>();
}
while (true)
{
// find the earliest entry whose loops aren't satisfied
int currentVertexIndex = 0;
//Debug.Log("~~FINDING NEW STARTING POINT~~");
for (currentVertexIndex = 0; currentVertexIndex < perimeter.Count - 2; currentVertexIndex++)
{
//Debug.Log("Index: " + currentVertexIndex + ", Is Egress = " + (perimeter[currentVertexIndex] is Egress) + ", loop count: " + perimeter[currentVertexIndex].loops.Count);
// for egresses:
if (perimeter[currentVertexIndex] is Egress)
{
//Debug.Log(((Egress)perimeter[currentVertexIndex]).cuts.Count);
// if this one is unsatisfied, break. We've found the earliest
if (perimeter[currentVertexIndex].loops.Count < ((Egress)perimeter[currentVertexIndex]).cuts.Count + 1)
{
break;
}
}
else // for original vertices
{
// if this one is unsatisfied, break. We've found the earliest
if (perimeter[currentVertexIndex].loops.Count < 1)
{
break;
}
}
}
string parString = "perimeter:";
foreach (Vertex vertex in perimeter)
{
parString += " " + perimeter.IndexOf(vertex) + ": (" + (vertex is Egress) + ")" + vertex.value;
}
//Debug.Log(parString);
//Debug.Log("finished with: " + currentVertexIndex);
//Debug.Log("perimeter size: " + perimeter.Count);
// we've satisfied all loops, which is our exit condition
if (currentVertexIndex == perimeter.Count - 2)
{
break;
}
// now that we've found the beginning of a loop, it's time to find the rest
Vertex initialVertex = perimeter[currentVertexIndex];
// determine whether this loop should be filled or not
EdgeLoop loop = new EdgeLoop();
// the loop defines either a surface or a hole, and we can determine that by looking at our starting entry
// the starting entry can be one of two cases:
// 1. an egress which is already part of one loop
if (initialVertex is Egress)
{
// in this case, the new loop is the opposite of whatever the previous loop is
loop.filled = !initialVertex.loops[initialVertex.loops.Count - 1].filled;
// also, if the initial vertex is an egress, we should add it and move on to the next perimeter value,
// so as not to traverse backwards along the cut
/*Cut furthestCut = ((Egress)initialVertex).GetFurthestCut(perimeter);
*
* loop.vertices.Add(perimeter[currentVertexIndex]);
* perimeter[currentVertexIndex].loops.Add(loop);
* currentVertexIndex++;*/
}
else // 2. a vertex of the original triangle
{
// in this case, if the vertex is contained by the bound, the loop is a surface, otherwise it's a hole
loop.filled = initialVertex.containedByBound;
}
// traverse forward in the ordered list, following each cut, until we reach the initial point
// once the inital entry is reached again, we have identified a loop, and can add it to the pile
int tooMuch = 0;
//Debug.Log("starting new loop");
do
{
// if the current vertex is an egress
tooMuch++;
if (tooMuch > 100)
{
Debug.Log("too long");
throw new System.ApplicationException();
break;
}
//Debug.Log(currentVertexIndex);
Cut furthestCut = null;
if (perimeter[currentVertexIndex] is Egress)
{
furthestCut = ((Egress)perimeter[currentVertexIndex]).GetFurthestCut(perimeter);
}
if (furthestCut != null)
{
currentVertexIndex = TraverseCut(furthestCut, loop, perimeter, currentVertexIndex);
if (perimeter[currentVertexIndex] == initialVertex)// if we arrived at the initial vertex
{
loop.vertices.RemoveAt(loop.vertices.Count - 1);
break;
}
// if there's more than one cut on the vertex, we need to potentially
while (((Egress)perimeter[currentVertexIndex]).cuts.Count > 1)
{
//Debug.Log("Double traversal");
// select cut
Cut toIgnore = null;
foreach (Cut cut in ((Egress)perimeter[currentVertexIndex]).cuts)
{
if (cut[cut.Count - 1] == furthestCut[0])
{
toIgnore = cut;
break;
}
}
furthestCut = ((Egress)perimeter[currentVertexIndex]).GetFurthestCut(perimeter, toIgnore, currentVertexIndex, perimeter.IndexOf(initialVertex));
if (furthestCut != null)
{
currentVertexIndex = TraverseCut(furthestCut, loop, perimeter, currentVertexIndex);
}
else
{
//Debug.Log("Couldn't find double traversal");
break;
}
if (perimeter[currentVertexIndex] == initialVertex)// if we arrived at the initial vertex
{
loop.vertices.RemoveAt(loop.vertices.Count - 1);
goto EndOfDoWhile;
}
}
}
else
{
// add current vertex to loop
loop.vertices.Add(perimeter[currentVertexIndex]);
perimeter[currentVertexIndex].loops.Add(loop);
}
// increment the current index by 1
currentVertexIndex++;
if (currentVertexIndex >= perimeter.Count)
{
string listString = "";
foreach (Vertex vertex in loop.vertices)
{
listString += " " + perimeter.IndexOf(vertex);
}
Debug.Log("Failed to create loop, (Filled: " + loop.filled + ") :: " + listString);
}
// once the current vertex loops around to the start, we're done
} while (perimeter[currentVertexIndex] != initialVertex);
EndOfDoWhile:
//Debug.Log("terminated");
loops.Add(loop);
}
if (debug)
{
foreach (EdgeLoop loop in loops)
{
string listString = "";
foreach (Vertex vertex in loop.vertices)
{
listString += " " + perimeter.IndexOf(vertex);
}
Debug.Log("Created loop, (Filled: " + loop.filled + ") :: " + listString);
}
}
// now that we've created all loops that intersect the edge of the triangle, we can start on loops that float as islands
List <Vertex> unusedVertices = new List <Vertex>();
foreach (Vertex intersection in internalIntersections)
{
if (!intersection.usedInLoop)
{
unusedVertices.Add(intersection);
}
}
Debug.Log(unusedVertices.Count);
while (unusedVertices.Count > 0)
{
Vertex currentVertex = unusedVertices[unusedVertices.Count - 1];
unusedVertices.RemoveAt(unusedVertices.Count - 1);
DiscoverInternalLoop(currentVertex, unusedVertices, loops);
}
foreach (EdgeLoop loop in loops)
{
EdgeLoop nestedLoop = loop.nestedLoop;
EdgeLoop previousLoop = loop;
while (nestedLoop != null)
{
nestedLoop.filled = !previousLoop.filled;
previousLoop = nestedLoop;
nestedLoop = nestedLoop.nestedLoop;
}
}
return(loops);
}
