// arc utils
public static IEnumerable <PolylinePoint> GetArcPoints(PolylinePoint a, PolylinePoint b, Vector3 normA, Vector3 normB, Vector3 center, float radius, int count)
{
count = Mathf.Max(2, count); // at least 2
PolylinePoint DirToPt(Vector3 dir, float t)
{
PolylinePoint p = t <= 0 ? a : (t >= 1 ? b : PolylinePoint.Lerp(a, b, t));
p.point = center + dir * radius;
return(p);
}
yield return(DirToPt(normA, 0));
for (int i = 1; i < count - 1; i++)
{
float t = i / (count - 1f);
yield return(DirToPt(Vector3.Slerp(normA, normB, t), t));
}
yield return(DirToPt(normB, 1));
}
[MethodImpl(INLINE)] public static PolylinePoint WeightedSum(Vector4 w, PolylinePoint a, PolylinePoint b, PolylinePoint c, PolylinePoint d) => w.x * a + w.y * b + w.z * c + w.w * d;
public static PolylinePoint CubicBezier(PolylinePoint a, PolylinePoint b, PolylinePoint c, PolylinePoint d, float t)
{
if (t <= 0f)
{
return(a);
}
if (t >= 1f)
{
return(d);
}
return(WeightedSum(GetCubicBezierWeights(t), a, b, c, d));
}
public static IEnumerable <PolylinePoint> CubicBezierPointsSkipFirstMatchStyle(PolylinePoint style, Vector3 a, Vector3 b, Vector3 c, Vector3 d, int count)
{
// skip first point
for (int i = 1; i < count - 1; i++)
{
float t = i / (count - 1f);
PolylinePoint pp = style;
pp.point = CubicBezier(a, b, c, d, t);
yield return(pp);
}
PolylinePoint ppEnd = style;
ppEnd.point = d;
yield return(ppEnd);
}
// bezier utils
public static IEnumerable <PolylinePoint> CubicBezierPointsSkipFirst(PolylinePoint a, PolylinePoint b, PolylinePoint c, PolylinePoint d, int count)
{
// skip first point
for (int i = 1; i < count - 1; i++)
{
float t = i / (count - 1f);
yield return(CubicBezier(a, b, c, d, t));
}
yield return(d);
}
public static void GenPolylineMesh(Mesh mesh, IList <PolylinePoint> path, bool closed, PolylineJoins joins, bool useColors)
{
mesh.Clear(); // todo maybe not always do this you know?
int pointCount = path.Count;
if (pointCount < 2)
{
return;
}
if (pointCount == 2 && closed)
{
closed = false;
}
PolylinePoint firstPoint = path[0];
PolylinePoint lastPoint = path[path.Count - 1];
// if the last point is at the same place as the first and it's closed, ignore the last point
if ((closed || pointCount == 2) && SamePosition(firstPoint.point, lastPoint.point))
{
pointCount--; // ignore last point
if (pointCount < 2) // check point count again
{
return;
}
lastPoint = path[path.Count - 2]; // second last point technically
}
// only mitered joints can be in the same submesh at the moment
bool separateJoinMesh = joins.HasJoinMesh();
bool isSimpleJoin = joins.HasSimpleJoin(); // only used when join meshes exist
int vertsPerPathPoint = separateJoinMesh ? 5 : 2;
int trianglesPerSegment = separateJoinMesh ? 4 : 2;
int vertexCount = pointCount * vertsPerPathPoint;
int vertexCountTotal = vertexCount;
int segmentCount = closed ? pointCount : pointCount - 1;
int triangleCount = segmentCount * trianglesPerSegment;
int triangleIndexCount = triangleCount * 3;
// Joins mesh data
int[] meshJoinsTriangles = default;
int joinVertsPerJoin = default;
if (separateJoinMesh)
{
joinVertsPerJoin = isSimpleJoin ? 3 : 5;
int joinCount = closed ? pointCount : pointCount - 2;
int joinTrianglesPerJoin = isSimpleJoin ? 1 : 3;
int joinTriangleIndexCount = joinCount * joinTrianglesPerJoin * 3;
int vertexCountJoins = joinCount * joinVertsPerJoin;
vertexCountTotal += vertexCountJoins;
meshJoinsTriangles = new int[joinTriangleIndexCount];
}
Color[] meshColors = useColors ? new Color[vertexCountTotal] : null;
Vector3[] meshVertices = new Vector3[vertexCountTotal];
#if UNITY_2019_3_OR_NEWER
Vector4[] meshUv0 = new Vector4[vertexCountTotal]; // UVs for masking. z contains endpoint status, w is thickness
Vector3[] meshUv1Prevs = new Vector3[vertexCountTotal];
Vector3[] meshUv2Nexts = new Vector3[vertexCountTotal];
#else
// List<> is the only supported vec3 UV assignment method prior to Unity 2019.3
List <Vector4> meshUv0 = new List <Vector4>(new Vector4[vertexCountTotal]);
List <Vector3> meshUv1Prevs = new List <Vector3>(new Vector3[vertexCountTotal]);
List <Vector3> meshUv2Nexts = new List <Vector3>(new Vector3[vertexCountTotal]);
#endif
int[] meshTriangles = new int[triangleIndexCount];
// indices used per triangle
int iv0, iv1, iv2 = 0, iv3 = 0, iv4 = 0;
int ivj0 = 0, ivj1 = 0, ivj2 = 0, ivj3 = 0, ivj4 = 0;
int triId = 0;
int triIdJoin = 0;
for (int i = 0; i < pointCount; i++)
{
bool isLast = i == pointCount - 1;
bool isFirst = i == 0;
bool makeJoin = closed || (!isLast && !isFirst);
bool isEndpoint = closed == false && (isFirst || isLast);
float uvEndpointValue = isEndpoint ? (isFirst ? -1 : 1) : 0;
void SetUv0(int id, float x, float y) => meshUv0[id] = new Vector4(x, y, uvEndpointValue, path[i].thickness);
// Indices & verts
Vector3 vert = path[i].point;
Color color = useColors ? path[i].color : default;
iv0 = i * vertsPerPathPoint;
if (separateJoinMesh)
{
iv1 = iv0 + 1; // "prev" outer
iv2 = iv0 + 2; // "next" outer
iv3 = iv0 + 3; // "prev" inner
iv4 = iv0 + 4; // "next" inner
meshVertices[iv0] = vert;
meshVertices[iv1] = vert;
meshVertices[iv2] = vert;
meshVertices[iv3] = vert;
meshVertices[iv4] = vert;
if (useColors)
{
meshColors[iv0] = color;
meshColors[iv1] = color;
meshColors[iv2] = color;
meshColors[iv3] = color;
meshColors[iv4] = color;
}
// joins mesh
if (makeJoin)
{
int joinIndex = (closed ? i : i - 1); // Skip first if open
ivj0 = joinIndex * joinVertsPerJoin + vertexCount;
ivj1 = ivj0 + 1;
ivj2 = ivj0 + 2;
ivj3 = ivj0 + 3;
ivj4 = ivj0 + 4;
meshVertices[ivj0] = vert;
meshVertices[ivj1] = vert;
meshVertices[ivj2] = vert;
if (useColors)
{
meshColors[ivj0] = color;
meshColors[ivj1] = color;
meshColors[ivj2] = color;
}
if (isSimpleJoin == false)
{
meshVertices[ivj3] = vert;
meshVertices[ivj4] = vert;
if (useColors)
{
meshColors[ivj3] = color;
meshColors[ivj4] = color;
}
}
}
}
else
{
iv1 = iv0 + 1; // Inner vert
meshVertices[iv0] = vert;
meshVertices[iv1] = vert;
if (useColors)
{
meshColors[iv0] = color;
meshColors[iv1] = color;
}
}
// Setting up next/previous positions
Vector3 prevPos;
Vector3 nextPos;
if (i == 0)
{
prevPos = closed ? lastPoint.point : (firstPoint.point * 2 - path[1].point); // Mirror second point
nextPos = path[i + 1].point;
}
else if (i == pointCount - 1)
{
prevPos = path[i - 1].point;
nextPos = closed ? firstPoint.point : (path[pointCount - 1].point * 2 - path[pointCount - 2].point); // Mirror second last point
}
else
{
prevPos = path[i - 1].point;
nextPos = path[i + 1].point;
}
void SetPrevNext(int atIndex)
{
meshUv1Prevs[atIndex] = prevPos;
meshUv2Nexts[atIndex] = nextPos;
}
SetPrevNext(iv0);
SetPrevNext(iv1);
if (separateJoinMesh)
{
SetPrevNext(iv2);
SetPrevNext(iv3);
SetPrevNext(iv4);
if (makeJoin)
{
SetPrevNext(ivj0);
SetPrevNext(ivj1);
SetPrevNext(ivj2);
if (isSimpleJoin == false)
{
SetPrevNext(ivj3);
SetPrevNext(ivj4);
}
}
}
if (separateJoinMesh)
{
SetUv0(iv0, 0, 0);
SetUv0(iv1, -1, -1);
SetUv0(iv2, -1, 1);
SetUv0(iv3, 1, -1);
SetUv0(iv4, 1, 1);
if (makeJoin)
{
SetUv0(ivj0, 0, 0);
if (isSimpleJoin)
{
SetUv0(ivj1, 1, -1);
SetUv0(ivj2, 1, 1);
}
else
{
SetUv0(ivj1, 1, -1);
SetUv0(ivj2, -1, -1);
SetUv0(ivj3, -1, 1);
SetUv0(ivj4, 1, 1);
}
}
}
else
{
SetUv0(iv0, -1, i);
SetUv0(iv1, 1, i);
}
if (isLast == false || closed)
{
// clockwise order
void AddQuad(int a, int b, int c, int d)
{
meshTriangles[triId++] = a;
meshTriangles[triId++] = b;
meshTriangles[triId++] = c;
meshTriangles[triId++] = c;
meshTriangles[triId++] = d;
meshTriangles[triId++] = a;
}
if (separateJoinMesh)
{
int rootCenter = iv0;
int rootOuter = iv2;
int rootInner = iv4;
int nextCenter = isLast ? 0 : rootCenter + vertsPerPathPoint;
int nextOuter = nextCenter + 1;
int nextInner = nextCenter + 3;
AddQuad(rootCenter, rootOuter, nextOuter, nextCenter);
AddQuad(nextCenter, nextInner, rootInner, rootCenter);
if (makeJoin)
{
meshJoinsTriangles[triIdJoin++] = ivj0;
meshJoinsTriangles[triIdJoin++] = ivj1;
meshJoinsTriangles[triIdJoin++] = ivj2;
if (isSimpleJoin == false)
{
meshJoinsTriangles[triIdJoin++] = ivj2;
meshJoinsTriangles[triIdJoin++] = ivj3;
meshJoinsTriangles[triIdJoin++] = ivj0;
meshJoinsTriangles[triIdJoin++] = ivj0;
meshJoinsTriangles[triIdJoin++] = ivj3;
meshJoinsTriangles[triIdJoin++] = ivj4;
}
}
}
else
{
int rootOuter = iv0;
int rootInner = iv1;
int nextOuter = isLast ? 0 : rootOuter + vertsPerPathPoint;
int nextInner = nextOuter + 1;
AddQuad(rootInner, rootOuter, nextOuter, nextInner);
}
}
}
// assign to segments mesh
mesh.vertices = meshVertices;
mesh.subMeshCount = 2;
mesh.SetTriangles(meshTriangles, 0);
mesh.SetTriangles(meshJoinsTriangles, 1);
mesh.SetUVs(0, meshUv0);
mesh.SetUVs(1, meshUv1Prevs);
mesh.SetUVs(2, meshUv2Nexts);
if (useColors)
{
mesh.colors = meshColors;
}
}