public PathList Divide(NativeArray <Triangle> triangles, Allocator allocator)
{
var result = new DynamicPathList(6 * maxCount, maxCount, allocator);
var bufferA = new DynamicArray <Triangle>(maxCount / 3, tempAllocator);
var bufferB = new DynamicArray <Triangle>(maxCount / 3, tempAllocator);
bufferA.Add(triangles);
do
{
for (int i = 0; i < bufferA.Count; ++i)
{
var triangle = bufferA[i];
if (Divide(triangle, ref bufferB, ref result))
{
if (result.layouts.Count >= maxCount)
{
goto onFinish;
}
}
}
bufferA.RemoveAll();
if (bufferB.Count > 0)
{
for (int i = 0; i < bufferB.Count; ++i)
{
var triangle = bufferB[i];
if (Divide(triangle, ref bufferA, ref result))
{
if (result.layouts.Count >= maxCount)
{
goto onFinish;
}
}
}
}
bufferB.RemoveAll();
} while (bufferA.Count > 0);
onFinish:
bufferA.Dispose();
bufferB.Dispose();
return(result.Convert());
}
private bool Divide(Triangle triangle, ref DynamicArray <Triangle> triangles, ref DynamicPathList result)
{
float s = triangle.Area;
if (s < this.minArea)
{
float value = random(s);
switch (this.fadeSpawnStrategy)
{
case FadeSpawnStrategy.no:
return(false);
case FadeSpawnStrategy.random:
if (value < 0.5f)
{
return(false);
}
break;
case FadeSpawnStrategy.randomFade:
if (value > s / this.minArea)
{
return(false);
}
break;
default:
throw new ArgumentOutOfRangeException();
}
}
var A = triangle.a;
var B = triangle.b;
var C = triangle.c;
var AB = Vector2.Distance(A, B);
var BC = Vector2.Distance(B, C);
var CA = Vector2.Distance(C, A);
float p = AB + BC + CA;
float r = 2 * s / p;
float Ox = (BC * A.x + CA * B.x + AB * C.x) / p;
float Oy = (BC * A.y + CA * B.y + AB * C.y) / p;
var O = new Vector2(Ox, Oy);
float Ac = Vector2.Dot(O - A, B - A) / AB;
float Ba = Vector2.Dot(O - B, C - B) / BC;
float Cb = Vector2.Dot(O - C, A - C) / CA;
var nAB = A.Unit(B, AB);
var nBC = B.Unit(C, BC);
var nCA = C.Unit(A, CA);
var CA0 = C + nCA * (Cb * (CA - r) / CA);
var CA1 = CA0 + nCA * r;
var AB0 = A + nAB * (Ac * (AB - r) / AB);
var AB1 = AB0 + nAB * r;
var BC0 = B + nBC * (Ba * (BC - r) / BC);
var BC1 = BC0 + nBC * r;
triangles.Add(new Triangle(CA1, triangle.a, AB0));
triangles.Add(new Triangle(AB1, triangle.b, BC0));
triangles.Add(new Triangle(BC1, triangle.c, CA0));
var path = new NativeArray <Vector2>(6, tempAllocator);
path[0] = CA0;
path[1] = CA1;
path[2] = AB0;
path[3] = AB1;
path[4] = BC0;
path[5] = BC1;
result.Add(path, true);
path.Dispose();
return(true);
}
