bool Flip(NativeArray <float2> points, ref NativeArray <int> stack, ref int stackCount, int a, int b, int x)
{
int y = OppositeOf(a, b);
if (y < 0)
{
return(true);
}
if (b < a)
{
int tmp = a;
a = b;
b = tmp;
tmp = x;
x = y;
y = tmp;
}
if (FindConstraint(a, b) != -1)
{
return(true);
}
if (UTess.IsInsideCircle(points[a], points[b], points[x], points[y]))
{
if ((2 + stackCount) >= stack.Length)
{
return(false);
}
stack[stackCount++] = a;
stack[stackCount++] = b;
}
return(true);
}
internal bool ApplyDelaunay(NativeArray <float2> points, NativeArray <int2> edges)
{
NativeArray <int> stack = new NativeArray <int>(m_NumPoints * (m_NumPoints + 1), m_Allocator);
int stackCount = 0;
var valid = true;
PrepareDelaunay(edges, m_NumEdges);
for (int a = 0; valid && (a < m_NumPoints); ++a)
{
UStar star = m_Stars[a];
for (int j = 1; j < star.pointCount; j += 2)
{
int b = star.points[j];
if (b < a)
{
continue;
}
if (FindConstraint(a, b) >= 0)
{
continue;
}
int x = star.points[j - 1], y = -1;
for (int k = 1; k < star.pointCount; k += 2)
{
if (star.points[k - 1] == b)
{
y = star.points[k];
break;
}
}
if (y < 0)
{
continue;
}
if (UTess.IsInsideCircle(points[a], points[b], points[x], points[y]))
{
if ((2 + stackCount) >= stack.Length)
{
valid = false;
break;
}
stack[stackCount++] = a;
stack[stackCount++] = b;
}
}
}
var flipFlops = m_NumPoints * m_NumPoints;
while (stackCount > 0 && valid)
{
int b = stack[stackCount - 1];
stackCount--;
int a = stack[stackCount - 1];
stackCount--;
int x = -1, y = -1;
UStar star = m_Stars[a];
for (int i = 1; i < star.pointCount; i += 2)
{
int s = star.points[i - 1];
int t = star.points[i];
if (s == b)
{
y = t;
}
else if (t == b)
{
x = s;
}
}
if (x < 0 || y < 0)
{
continue;
}
if (!UTess.IsInsideCircle(points[a], points[b], points[x], points[y]))
{
continue;
}
EdgeFlip(a, b);
valid = Flip(points, ref stack, ref stackCount, x, a, y);
valid = valid && Flip(points, ref stack, ref stackCount, a, y, x);
valid = valid && Flip(points, ref stack, ref stackCount, y, b, x);
valid = valid && Flip(points, ref stack, ref stackCount, b, x, y);
valid = valid && (--flipFlops > 0);
}
stack.Dispose();
return(valid);
}
