// A parent is a shape which fully contains another shape
public bool IsParentOf(CompositeSolidShapeData otherShape)
{
if (otherShape.parents.Contains(this))
{
return(true);
}
if (parents.Contains(otherShape))
{
return(false);
}
// check if first point in otherShape is inside this shape. If not, parent test fails.
// if yes, then continue to line seg intersection test between the two shapes
// (this point test is important because without it, if all line seg intersection tests fail,
// we wouldn't know if otherShape is entirely inside or entirely outside of this shape)
bool pointInsideShape = false;
for (int i = 0; i < triangles.Length; i += 3)
{
if (Maths2D.PointInTriangle(polygon.points[triangles[i]], polygon.points[triangles[i + 1]], polygon.points[triangles[i + 2]], otherShape.points[0]))
{
pointInsideShape = true;
break;
}
}
if (!pointInsideShape)
{
return(false);
}
// Check for intersections between line segs of this shape and otherShape (any intersections will fail the parent test)
for (int i = 0; i < points.Length; i++)
{
LineSegment parentSeg = new LineSegment(points[i], points[(i + 1) % points.Length]);
for (int j = 0; j < otherShape.points.Length; j++)
{
LineSegment childSeg = new LineSegment(otherShape.points[j], otherShape.points[(j + 1) % otherShape.points.Length]);
if (Maths2D.LineSegmentsIntersect(parentSeg.a, parentSeg.b, childSeg.a, childSeg.b))
{
return(false);
}
}
}
return(true);
}
// Test if the shapes overlap partially (test will fail if one shape entirely contains other shape, i.e. one is parent of the other).
public bool OverlapsPartially(CompositeSolidShapeData otherShape)
{
// Check for intersections between line segs of this shape and otherShape (any intersection will validate the overlap test)
for (int i = 0; i < points.Length; i++)
{
LineSegment segA = new LineSegment(points[i], points[(i + 1) % points.Length]);
for (int j = 0; j < otherShape.points.Length; j++)
{
LineSegment segB = new LineSegment(otherShape.points[j], otherShape.points[(j + 1) % otherShape.points.Length]);
if (Maths2D.LineSegmentsIntersect(segA.a, segA.b, segB.a, segB.b))
{
return(true);
}
}
}
return(false);
}
public void Process()
{
// Generate array of valid shape data
CompositeSolidShapeData[] eligibleShapes = shapes.Select(x => new CompositeSolidShapeData(x.points.ToArray())).Where(x => x.IsValidShape).ToArray();
// Set parents for all shapes. A parent is a shape which completely contains another shape.
for (int i = 0; i < eligibleShapes.Length; i++)
{
for (int j = 0; j < eligibleShapes.Length; j++)
{
if (i == j)
{
continue;
}
if (eligibleShapes[i].IsParentOf(eligibleShapes[j]))
{
eligibleShapes[j].parents.Add(eligibleShapes[i]);
}
}
}
// Holes are shapes with an odd number of parents.
CompositeSolidShapeData[] holeShapes = eligibleShapes.Where(x => x.parents.Count % 2 != 0).ToArray();
foreach (CompositeSolidShapeData holeShape in holeShapes)
{
// The most immediate parent (i.e the smallest parent shape) will be the one that has the highest number of parents of its own.
CompositeSolidShapeData immediateParent = holeShape.parents.OrderByDescending(x => x.parents.Count).First();
immediateParent.holes.Add(holeShape);
}
// Solid shapes have an even number of parents
CompositeSolidShapeData[] solidShapes = eligibleShapes.Where(x => x.parents.Count % 2 == 0).ToArray();
foreach (CompositeSolidShapeData solidShape in solidShapes)
{
solidShape.ValidateHoles();
}
// Create polygons from the solid shapes and their associated hole shapes
Polygon[] polygons = solidShapes.Select(x => new Polygon(x.polygon.points, x.holes.Select(h => h.polygon.points).ToArray())).ToArray();
// Flatten the points arrays from all polygons into a single array, and convert the vector2s to vector3s.
vertices = polygons.SelectMany(x => x.points.Select(v2 => new Vector3(v2.x, height, v2.y))).ToArray();
// Triangulate each polygon and flatten the triangle arrays into a single array.
List <int> allTriangles = new List <int>();
int startVertexIndex = 0;
for (int i = 0; i < polygons.Length; i++)
{
Triangulator triangulator = new Triangulator(polygons[i]);
int[] polygonTriangles = triangulator.Triangulate();
for (int j = 0; j < polygonTriangles.Length; j++)
{
allTriangles.Add(polygonTriangles[j] + startVertexIndex);
}
startVertexIndex += polygons[i].numPoints;
}
triangles = allTriangles.ToArray();
}
