private void CheckEdges(SubdivisionSearch search)
{
foreach (SubdivisionEdge edge in search.Source.Edges.Values)
{
var edgeElement = new SubdivisionElement(edge);
var twinElement = new SubdivisionElement(edge._twin);
// SubdivisionSearch always returns lexicographically increasing half-edges
PointD start = edge._origin, end = edge._twin._origin;
int result = PointDComparerX.CompareEpsilon(start, end, search.Source.Epsilon);
var element = (result < 0 ? edgeElement : twinElement);
PointD q = new PointD((start.X + end.X) / 2, (start.Y + end.Y) / 2);
Assert.AreEqual(element, search.Find(q));
// brute force search may return half-edge or its twin
var found = search.Source.Find(q, 1e-10);
Assert.IsTrue(found == edgeElement || found == twinElement);
// brute force search also supports comparison epsilon
PointD offset = GeoAlgorithms.RandomPoint(-0.1, -0.1, 0.2, 0.2);
found = search.Source.Find(q + offset, 0.25);
Assert.IsTrue(found == edgeElement || found == twinElement);
}
}
private void CheckVertices(SubdivisionSearch search)
{
foreach (PointD vertex in search.Source.Vertices.Keys)
{
var element = new SubdivisionElement(vertex);
Assert.AreEqual(element, search.Find(vertex));
Assert.AreEqual(element, search.Source.Find(vertex));
// brute force search also supports comparison epsilon
PointD offset = GeoAlgorithms.RandomPoint(-0.1, -0.1, 0.2, 0.2);
Assert.AreEqual(element, search.Source.Find(vertex + offset, 0.25));
}
}
public void Empty()
{
var search = new SubdivisionSearch(new Subdivision());
search.Validate();
for (int i = 0; i < 10; i++)
{
PointD q = GeoAlgorithms.RandomPoint(-100, -100, 200, 200);
Assert.IsTrue(search.Find(q).IsUnboundedFace);
Assert.IsTrue(search.Source.Find(q).IsUnboundedFace);
}
}
private SubdivisionSearch CheckSearch(params LineD[] lines)
{
Subdivision division = Subdivision.FromLines(lines);
division.Validate();
SubdivisionSearch search = new SubdivisionSearch(division);
search.Validate();
CheckVertices(search);
CheckEdges(search);
PointD[] points = new[] {
new PointD(+1, +1), new PointD(+1, -1),
new PointD(-1, +1), new PointD(-1, -1)
};
if (division.Faces.Count == 1)
{
foreach (PointD point in points)
{
Assert.IsTrue(search.Find(point).IsUnboundedFace);
Assert.IsTrue(division.Find(point).IsUnboundedFace);
}
}
else
{
var element = new SubdivisionElement(division.Faces[1]);
foreach (PointD point in points)
{
Assert.AreEqual(element, search.Find(point));
Assert.AreEqual(element, division.Find(point));
}
}
points = new[] {
new PointD(+10, +10), new PointD(+10, -10),
new PointD(-10, +10), new PointD(-10, -10)
};
foreach (PointD point in points)
{
Assert.IsTrue(search.Find(point).IsUnboundedFace);
Assert.IsTrue(division.Find(point).IsUnboundedFace);
}
return(search);
}
private SubdivisionSearch CheckSearch(Subdivision division)
{
division.Validate();
SubdivisionSearch search = new SubdivisionSearch(division);
search.Validate();
CheckVertices(search);
CheckEdges(search);
foreach (SubdivisionFace face in division.Faces.Values)
{
if (face.OuterEdge == null)
{
continue;
}
PointD centroid = face.OuterEdge.CycleCentroid;
var element = new SubdivisionElement(face);
Assert.AreEqual(element, search.Find(centroid));
Assert.AreEqual(element, division.Find(centroid));
}
return(search);
}
private void SubdivisionSearchTest(bool random)
{
Stopwatch timer = new Stopwatch();
var testCases = _subdivSearchTestCases;
Output(String.Format("{0,6}", " "));
foreach (TestCase test in testCases)
{
Output(String.Format("{0,12}", test.Name));
}
Output("\n");
const int outerLoop = 100, innerLoop = 200;
const int iterations = outerLoop * innerLoop;
PointD[] query = new PointD[innerLoop];
PolygonGrid grid = null;
int sizeMin, sizeMax, sizeStep;
if (random)
{
sizeMin = 100; sizeMax = 1200; sizeStep = 100;
}
else
{
sizeMin = 6; sizeMax = 30; sizeStep = 2;
RegularPolygon polygon = new RegularPolygon(10, 4, PolygonOrientation.OnEdge);
grid = new PolygonGrid(polygon);
}
for (int size = sizeMin; size <= sizeMax; size += sizeStep)
{
Subdivision division;
if (random)
{
// create subdivision from random lines (few faces)
division = CreateSubdivision(size, 1e-10);
}
else
{
// create subdivision from grid of diamonds (many faces)
grid.Element = new RegularPolygon(900 / size, 4, PolygonOrientation.OnEdge);
grid.Size = new SizeI(size, size);
division = grid.ToSubdivision(PointD.Empty).Source;
}
var ordered = new SubdivisionSearch(division, true);
var randomized = new SubdivisionSearch(division, false);
// test cases: BruteForce, Ordered, Randomized
testCases[0].FindSubdivision = (q) => division.Find(q, division.Epsilon);
testCases[1].FindSubdivision = (q) => ordered.Find(q);
testCases[2].FindSubdivision = (q) => randomized.Find(q);
// trigger JIT compilation and reset ticks
foreach (TestCase test in testCases)
{
test.FindSubdivision(PointD.Empty);
test.Ticks = 0;
}
for (int j = 0; j < outerLoop; j++)
{
for (int k = 0; k < query.Length; k++)
{
query[k] = GeoAlgorithms.RandomPoint(0, 0, 1000, 1000);
}
foreach (TestCase test in testCases)
{
timer.Restart();
for (int k = 0; k < query.Length; k++)
{
test.FindSubdivision(query[k]);
}
timer.Stop();
test.Ticks += timer.ElapsedTicks;
}
}
Output(String.Format("{0,6:N0}", division.Edges.Count / 2));
foreach (TestCase test in testCases)
{
Output(String.Format("{0,12:N2}", AverageMicrosecs(test.Ticks, iterations)));
}
Output("\n");
}
Output("\nTimes are µsec averages for subdivisions of the indicated edge count,\n");
if (random)
{
Output("based on random line sets (few faces, completely random edges).\n");
}
else
{
Output("based on grids of squares (many faces, strictly ordered edges).\n");
}
}
