/// Builds an array of edges that connect to only one triangle.
/// In other words, the outline of the mesh
public static Edge[] BuildManifoldEdges(GOMesh mesh)
{
// Build a edge list for all unique edges in the mesh
Edge[] edges = BuildEdges(mesh.vertices.Length, mesh.triangles);
// We only want edges that connect to a single triangle
ArrayList culledEdges = new ArrayList();
foreach (Edge edge in edges)
{
if (edge.faceIndex[0] == edge.faceIndex[1])
{
culledEdges.Add(edge);
}
}
return(culledEdges.ToArray(typeof(Edge)) as Edge[]);
}
public GOMesh(GOMesh premesh)
{
vertices = premesh.vertices;
triangles = premesh.triangles;
uv = premesh.uv;
}
public static void ExtrudeMesh(GOMesh srcMesh, GOMesh extrudedMesh, Matrix4x4[] extrusion, Edge[] edges, bool invertFaces)
{
int extrudedVertexCount = edges.Length * 2 * extrusion.Length;
int triIndicesPerStep = edges.Length * 6;
int extrudedTriIndexCount = triIndicesPerStep * (extrusion.Length - 1);
Vector3[] inputVertices = srcMesh.vertices;
Vector2[] inputUV = srcMesh.uv;
int[] inputTriangles = srcMesh.triangles;
Vector3[] vertices = new Vector3[extrudedVertexCount + srcMesh.vertices.Length * 2];
Vector2[] uvs = new Vector2[vertices.Length];
int[] triangles = new int[extrudedTriIndexCount + inputTriangles.Length * 2];
// Build extruded vertices
int v = 0;
for (int i = 0; i < extrusion.Length; i++)
{
Matrix4x4 matrix = extrusion[i];
float vcoord = (float)i / (extrusion.Length - 1);
float factor = (extrusion.Length - 1) - ((float)i / (extrusion.Length - 1)) * srcMesh.sliceHeight;
//foreach (Edge e in edges)
for (int k = 0; k < edges.Length; k++)
{
Edge e = edges[k];
vertices[v + 0] = matrix.MultiplyPoint(inputVertices[e.vertexIndex[0]]);
vertices[v + 1] = matrix.MultiplyPoint(inputVertices[e.vertexIndex[1]]);
switch (srcMesh.uvMappingStyle)
{
case GOUVMappingStyle.TopAndSidesRepeated:
Matrix4x4 mn;
if (i == extrusion.Length - 1)
{
mn = extrusion[0];
}
else
{
mn = extrusion[i + 1];
}
Vector3 p1 = mn.MultiplyPoint(inputVertices[e.vertexIndex[0]]);
Vector3 p2 = mn.MultiplyPoint(inputVertices[e.vertexIndex[1]]);
uvs[v + 0] = new Vector2(p1.x, -p1.y) / 100;
uvs[v + 1] = new Vector2(p2.x, -p2.y) / 100;
break;
case GOUVMappingStyle.TopRepeatedSidesStretched:
uvs[v + 0] = inputUV[e.vertexIndex[0]];
uvs[v + 1] = inputUV[e.vertexIndex[1]];
break;
case GOUVMappingStyle.TopFitSidesFit:
case GOUVMappingStyle.TopRepeatedSidesFit:
case GOUVMappingStyle.TopCenteredSidesFit:
uvs[v + 0] = new Vector2(1, extrusion.Length - 1 - i);
uvs[v + 1] = new Vector2(0, extrusion.Length - 1 - i);
break;
case GOUVMappingStyle.TopFitSidesRatio:
float hdist = Vector3.Distance(vertices[v + 0], vertices[v + 1]);
float vdist = srcMesh.sliceHeight;
int ratio = Mathf.CeilToInt(hdist / vdist);
uvs[v + 0] = new Vector2(1 * ratio, extrusion.Length - 1 - i);
uvs[v + 1] = new Vector2(0, extrusion.Length - 1 - i);
break;
case GOUVMappingStyle.TopFitSidesSliced:
hdist = Vector3.Distance(vertices[v + 0], vertices[v + 1]);
vdist = srcMesh.sliceHeight;
ratio = Mathf.CeilToInt(hdist / vdist);
float textureFactor = 1 / 3f;
int f = (extrusion.Length - 1 - i);
float offset = 0f;
if (srcMesh.Y > srcMesh.sliceHeight)
{
offset = textureFactor;
}
if (extrusion.Length == 2)
{
uvs[v + 0] = new Vector2(1 * ratio, textureFactor * f + offset);
uvs[v + 1] = new Vector2(0, textureFactor * f + offset);
break;
}
float x = f % 2 == 0 ? textureFactor : 1 - textureFactor; // (f/2f) - 0.25f;
if (i == 0)
{
x = extrusion.Length % 2 == 0 ? 1 : textureFactor;
}
else if (f == 0)
{
x = offset;
}
uvs[v + 0] = new Vector2(1 * ratio, x);
uvs[v + 1] = new Vector2(0, x);
break;
default:
break;
}
v += 2;
}
}
// Build cap vertices
// * The bottom mesh we scale along it's negative extrusion direction. This way extruding a half sphere results in a capsule.
for (int c = 0; c < 2; c++)
{
Matrix4x4 matrix = extrusion[c == 0 ? 0 : extrusion.Length - 1];
int firstCapVertex = c == 0 ? extrudedVertexCount : extrudedVertexCount + inputVertices.Length;
for (int i = 0; i < inputVertices.Length; i++)
{
vertices[firstCapVertex + i] = matrix.MultiplyPoint(inputVertices[i]);
uvs[firstCapVertex + i] = inputUV[i];
}
}
// Build extruded triangles
for (int i = 0; i < extrusion.Length - 1; i++)
{
int baseVertexIndex = (edges.Length * 2) * i;
int nextVertexIndex = (edges.Length * 2) * (i + 1);
for (int e = 0; e < edges.Length; e++)
{
int triIndex = i * triIndicesPerStep + e * 6;
triangles[triIndex + 0] = baseVertexIndex + e * 2;
triangles[triIndex + 1] = nextVertexIndex + e * 2;
triangles[triIndex + 2] = baseVertexIndex + e * 2 + 1;
triangles[triIndex + 3] = nextVertexIndex + e * 2;
triangles[triIndex + 4] = nextVertexIndex + e * 2 + 1;
triangles[triIndex + 5] = baseVertexIndex + e * 2 + 1;
}
}
// build cap triangles
int triCount = inputTriangles.Length / 3;
// Top
if (!srcMesh.separateTop)
{
int firstCapVertex = extrudedVertexCount;
int firstCapTriIndex = extrudedTriIndexCount;
for (int i = 0; i < triCount; i++)
{
triangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 1] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 0] + firstCapVertex;
}
}
else
{
int firstCapVertex = extrudedVertexCount;
int firstCapTriIndex = extrudedTriIndexCount;
extrudedMesh.topTriangles = new int[triangles.Length];
for (int i = 0; i < triCount; i++)
{
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 1] + firstCapVertex;
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 0] + firstCapVertex;
}
}
// Bottom
if (!srcMesh.separateBottom)
{
int firstCapVertex = extrudedVertexCount + inputVertices.Length;
int firstCapTriIndex = extrudedTriIndexCount + inputTriangles.Length;
for (int i = 0; i < triCount; i++)
{
triangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 0] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 1] + firstCapVertex;
}
}
else
{
int firstCapVertex = extrudedVertexCount + inputVertices.Length;
int firstCapTriIndex = extrudedTriIndexCount + inputTriangles.Length;
extrudedMesh.bottomTriangles = new int[triangles.Length];
for (int i = 0; i < triCount; i++)
{
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 0] + firstCapVertex;
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 1] + firstCapVertex;
}
}
if (invertFaces)
{
for (int i = 0; i < triangles.Length / 3; i++)
{
int temp = triangles[i * 3 + 0];
triangles[i * 3 + 0] = triangles[i * 3 + 1];
triangles[i * 3 + 1] = temp;
}
}
extrudedMesh.vertices = vertices;
extrudedMesh.uv = uvs;
extrudedMesh.triangles = triangles;
}
public static void ExtrudeMesh(GOMesh srcMesh, GOMesh extrudedMesh, Matrix4x4[] extrusion, bool invertFaces)
{
Edge[] edges = BuildManifoldEdges(srcMesh);
ExtrudeMesh(srcMesh, extrudedMesh, extrusion, edges, invertFaces);
}
/// <summary>
/// Recalculate the normals of a mesh based on an angle threshold. This takes
/// into account distinct vertices that have the same position.
/// </summary>
/// <param name="mesh"></param>
/// <param name="angle">
/// The smoothing angle. Note that triangles that already share
/// the same vertex will be smooth regardless of the angle!
/// </param>
public static void RecalculateNormals(this GOMesh mesh, float angle)
{
var cosineThreshold = Mathf.Cos(angle * Mathf.Deg2Rad);
var vertices = mesh.vertices;
var normals = new Vector3[vertices.Length];
var triangles = mesh.triangles;
int submeshCount = 0;
// Holds the normal of each triangle in each sub mesh.
var triNormals = new Vector3[submeshCount][];
var dictionary = new Dictionary <VertexKey, List <VertexEntry> >(vertices.Length);
for (var subMeshIndex = 0; subMeshIndex < submeshCount; ++subMeshIndex)
{
triNormals[subMeshIndex] = new Vector3[triangles.Length / 3];
for (var i = 0; i < triangles.Length; i += 3)
{
int i1 = triangles[i];
int i2 = triangles[i + 1];
int i3 = triangles[i + 2];
// Calculate the normal of the triangle
Vector3 p1 = vertices[i2] - vertices[i1];
Vector3 p2 = vertices[i3] - vertices[i1];
Vector3 normal = Vector3.Cross(p1, p2).normalized;
int triIndex = i / 3;
triNormals[subMeshIndex][triIndex] = normal;
List <VertexEntry> entry;
VertexKey key;
if (!dictionary.TryGetValue(key = new VertexKey(vertices[i1]), out entry))
{
entry = new List <VertexEntry>(4);
dictionary.Add(key, entry);
}
entry.Add(new VertexEntry(subMeshIndex, triIndex, i1));
if (!dictionary.TryGetValue(key = new VertexKey(vertices[i2]), out entry))
{
entry = new List <VertexEntry>();
dictionary.Add(key, entry);
}
entry.Add(new VertexEntry(subMeshIndex, triIndex, i2));
if (!dictionary.TryGetValue(key = new VertexKey(vertices[i3]), out entry))
{
entry = new List <VertexEntry>();
dictionary.Add(key, entry);
}
entry.Add(new VertexEntry(subMeshIndex, triIndex, i3));
}
}
// Each entry in the dictionary represents a unique vertex position.
foreach (var vertList in dictionary.Values)
{
for (var i = 0; i < vertList.Count; ++i)
{
var sum = new Vector3();
var lhsEntry = vertList[i];
for (var j = 0; j < vertList.Count; ++j)
{
var rhsEntry = vertList[j];
if (lhsEntry.VertexIndex == rhsEntry.VertexIndex)
{
sum += triNormals[rhsEntry.MeshIndex][rhsEntry.TriangleIndex];
}
else
{
// The dot product is the cosine of the angle between the two triangles.
// A larger cosine means a smaller angle.
var dot = Vector3.Dot(
triNormals[lhsEntry.MeshIndex][lhsEntry.TriangleIndex],
triNormals[rhsEntry.MeshIndex][rhsEntry.TriangleIndex]);
if (dot >= cosineThreshold)
{
sum += triNormals[rhsEntry.MeshIndex][rhsEntry.TriangleIndex];
}
}
}
normals[lhsEntry.VertexIndex] = sum.normalized;
}
}
mesh.normals = normals;
}
public static void ExtrudeMesh(GOMesh srcMesh, GOMesh extrudedMesh, Matrix4x4[] extrusion, Edge[] edges, bool invertFaces)
{
int extrudedVertexCount = edges.Length * 2 * extrusion.Length;
int triIndicesPerStep = edges.Length * 6;
int extrudedTriIndexCount = triIndicesPerStep * (extrusion.Length - 1);
Vector3[] inputVertices = srcMesh.vertices;
Vector2[] inputUV = srcMesh.uv;
int[] inputTriangles = srcMesh.triangles;
Vector3[] vertices = new Vector3[extrudedVertexCount + srcMesh.vertices.Length * 2];
Vector2[] uvs = new Vector2[vertices.Length];
int[] triangles = new int[extrudedTriIndexCount + inputTriangles.Length * 2];
// Build extruded vertices
int v = 0;
for (int i = 0; i < extrusion.Length; i++)
{
Matrix4x4 matrix = extrusion[i];
float vcoord = (float)i / (extrusion.Length - 1);
foreach (Edge e in edges)
{
vertices[v + 0] = matrix.MultiplyPoint(inputVertices[e.vertexIndex[0]]);
vertices[v + 1] = matrix.MultiplyPoint(inputVertices[e.vertexIndex[1]]);
uvs[v + 0] = new Vector2(inputUV[e.vertexIndex[0]].x, vcoord);
uvs[v + 1] = new Vector2(inputUV[e.vertexIndex[1]].x, vcoord);
v += 2;
}
}
// Build cap vertices
// * The bottom mesh we scale along it's negative extrusion direction. This way extruding a half sphere results in a capsule.
for (int c = 0; c < 2; c++)
{
Matrix4x4 matrix = extrusion[c == 0 ? 0 : extrusion.Length - 1];
int firstCapVertex = c == 0 ? extrudedVertexCount : extrudedVertexCount + inputVertices.Length;
for (int i = 0; i < inputVertices.Length; i++)
{
vertices[firstCapVertex + i] = matrix.MultiplyPoint(inputVertices[i]);
uvs[firstCapVertex + i] = inputUV[i];
}
}
// Build extruded triangles
for (int i = 0; i < extrusion.Length - 1; i++)
{
int baseVertexIndex = (edges.Length * 2) * i;
int nextVertexIndex = (edges.Length * 2) * (i + 1);
for (int e = 0; e < edges.Length; e++)
{
int triIndex = i * triIndicesPerStep + e * 6;
triangles[triIndex + 0] = baseVertexIndex + e * 2;
triangles[triIndex + 1] = nextVertexIndex + e * 2;
triangles[triIndex + 2] = baseVertexIndex + e * 2 + 1;
triangles[triIndex + 3] = nextVertexIndex + e * 2;
triangles[triIndex + 4] = nextVertexIndex + e * 2 + 1;
triangles[triIndex + 5] = baseVertexIndex + e * 2 + 1;
}
}
// build cap triangles
int triCount = inputTriangles.Length / 3;
// Top
if (!srcMesh.separateTop)
{
int firstCapVertex = extrudedVertexCount;
int firstCapTriIndex = extrudedTriIndexCount;
for (int i = 0; i < triCount; i++)
{
triangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 1] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 0] + firstCapVertex;
}
}
else
{
int firstCapVertex = extrudedVertexCount;
int firstCapTriIndex = extrudedTriIndexCount;
extrudedMesh.topTriangles = new int[triangles.Length];
for (int i = 0; i < triCount; i++)
{
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 1] + firstCapVertex;
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
extrudedMesh.topTriangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 0] + firstCapVertex;
}
}
// Bottom
if (!srcMesh.separateBottom)
{
int firstCapVertex = extrudedVertexCount + inputVertices.Length;
int firstCapTriIndex = extrudedTriIndexCount + inputTriangles.Length;
for (int i = 0; i < triCount; i++)
{
triangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 0] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
triangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 1] + firstCapVertex;
}
}
else
{
int firstCapVertex = extrudedVertexCount + inputVertices.Length;
int firstCapTriIndex = extrudedTriIndexCount + inputTriangles.Length;
extrudedMesh.bottomTriangles = new int[triangles.Length];
for (int i = 0; i < triCount; i++)
{
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 0] = inputTriangles[i * 3 + 0] + firstCapVertex;
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 1] = inputTriangles[i * 3 + 2] + firstCapVertex;
extrudedMesh.bottomTriangles[i * 3 + firstCapTriIndex + 2] = inputTriangles[i * 3 + 1] + firstCapVertex;
}
}
if (invertFaces)
{
for (int i = 0; i < triangles.Length / 3; i++)
{
int temp = triangles[i * 3 + 0];
triangles[i * 3 + 0] = triangles[i * 3 + 1];
triangles[i * 3 + 1] = temp;
}
}
extrudedMesh.vertices = vertices;
extrudedMesh.uv = uvs;
extrudedMesh.triangles = triangles;
}
