// rest of the code doesn't care about point format
// basic distance-based simplification
public static NFP simplifyRadialDist(NFP points, double?sqTolerance)
{
var prevPoint = points[0];
var newPoints = new NFP();
newPoints.AddPoint(prevPoint);
SvgPoint point = null;
int i = 1;
for (var len = points.length; i < len; i++)
{
point = points[i];
if (point.marked || getSqDist(point, prevPoint) > sqTolerance)
{
newPoints.AddPoint(point);
prevPoint = point;
}
}
if (prevPoint != point)
{
newPoints.AddPoint(point);
}
return(newPoints);
}
public void AddRectanglePart(int src, int ww = 50, int hh = 80)
{
int xx = 0;
int yy = 0;
NFP pl = new NFP();
Polygons.Add(pl);
pl.source = src;
pl.Points = new SvgPoint[] { };
pl.AddPoint(new SvgPoint(xx, yy));
pl.AddPoint(new SvgPoint(xx + ww, yy));
pl.AddPoint(new SvgPoint(xx + ww, yy + hh));
pl.AddPoint(new SvgPoint(xx, yy + hh));
}
static NFP boundingBox(NFP offset)
{
NFP ret = new NFP();
var maxx = offset.Points.Max(z => z.x);
var maxy = offset.Points.Max(z => z.y);
var minx = offset.Points.Min(z => z.x);
var miny = offset.Points.Min(z => z.y);
ret.AddPoint(new SvgPoint(minx, miny));
ret.AddPoint(new SvgPoint(maxx, miny));
ret.AddPoint(new SvgPoint(maxx, maxy));
ret.AddPoint(new SvgPoint(minx, maxy));
return(ret);
}
// simplification using Ramer-Douglas-Peucker algorithm
public static NFP simplifyDouglasPeucker(NFP points, double?sqTolerance)
{
var last = points.length - 1;
var simplified = new NFP();
simplified.AddPoint(points[0]);
simplifyDPStep(points, 0, last, sqTolerance, simplified);
simplified.push(points[last]);
return(simplified);
}
public static NFP clone(NFP p)
{
var newp = new NFP();
for (var i = 0; i < p.length; i++)
{
newp.AddPoint(new SvgPoint(
p[i].x,
p[i].y
));
}
return(newp);
}
public NFP ImportFromRawDetail(RawDetail raw, int src)
{
NFP po = null;
List <NFP> nfps = new List <NFP>();
foreach (var item in raw.Outers)
{
var nn = new NFP();
nfps.Add(nn);
foreach (var pitem in item.Points)
{
nn.AddPoint(new SvgPoint(pitem.X, pitem.Y));
}
}
if (nfps.Any())
{
var tt = nfps.OrderByDescending(z => z.Area).First();
po = tt;
po.Name = raw.Name;
foreach (var r in nfps)
{
if (r == tt)
{
continue;
}
if (po.children == null)
{
po.children = new List <NFP>();
}
po.children.Add(r);
}
po.source = src;
Polygons.Add(po);
}
return(po);
}
public static NFP cloneTree(NFP tree)
{
NFP newtree = new NFP();
foreach (var t in tree.Points)
{
newtree.AddPoint(new SvgPoint(t.x, t.y)
{
exact = t.exact
});
}
if (tree.children != null && tree.children.Count > 0)
{
newtree.children = new List <NFP>();
foreach (var c in tree.children)
{
newtree.children.Add(cloneTree(c));
}
}
return(newtree);
}
public NFP ToNfp()
{
NFP po = null;
List <NFP> nfps = new List <NFP>();
foreach (var item in Outers)
{
var nn = new NFP();
nfps.Add(nn);
foreach (var pitem in item.Points)
{
nn.AddPoint(new SvgPoint(pitem.X, pitem.Y));
}
}
if (nfps.Any())
{
var tt = nfps.OrderByDescending(z => z.Area).First();
po = tt;
po.Name = Name;
foreach (var r in nfps)
{
if (r == tt)
{
continue;
}
if (po.children == null)
{
po.children = new List <NFP>();
}
po.children.Add(r);
}
}
return(po);
}
public static NFP simplifyFunction(NFP polygon, bool inside)
{
var tolerance = 4 * Config.curveTolerance;
// give special treatment to line segments above this length (squared)
var fixedTolerance = 40 * Config.curveTolerance * 40 * Config.curveTolerance;
int i, j, k;
if (Config.simplify)
{
/*
* // use convex hull
* var hull = new ConvexHullGrahamScan();
* for(var i=0; i<polygon.length; i++){
* hull.addPoint(polygon[i].x, polygon[i].y);
* }
*
* return hull.getHull();*/
var hull = Background.getHull(polygon);
if (hull != null)
{
return(hull);
}
else
{
return(polygon);
}
}
var cleaned = cleanPolygon2(polygon);
if (cleaned != null && cleaned.length > 1)
{
polygon = cleaned;
}
else
{
return(polygon);
}
// polygon to polyline
var copy = polygon.slice(0);
copy.push(copy[0]);
// mark all segments greater than ~0.25 in to be kept
// the PD simplification algo doesn't care about the accuracy of long lines, only the absolute distance of each point
// we care a great deal
for (i = 0; i < copy.length - 1; i++)
{
var p1 = copy[i];
var p2 = copy[i + 1];
var sqd = (p2.x - p1.x) * (p2.x - p1.x) + (p2.y - p1.y) * (p2.y - p1.y);
if (sqd > fixedTolerance)
{
p1.marked = true;
p2.marked = true;
}
}
var simple = Simplify.simplify(copy, tolerance, true);
// now a polygon again
//simple.pop();
simple.Points = simple.Points.Take(simple.Points.Count() - 1).ToArray();
// could be dirty again (self intersections and/or coincident points)
simple = cleanPolygon2(simple);
// simplification process reduced poly to a line or point
if (simple == null)
{
simple = polygon;
}
var offsets = polygonOffsetDeepNest(simple, inside ? -tolerance : tolerance);
NFP offset = null;
double offsetArea = 0;
List <NFP> holes = new List <NFP>();
for (i = 0; i < offsets.Length; i++)
{
var area = GeometryUtil.polygonArea(offsets[i]);
if (offset == null || area < offsetArea)
{
offset = offsets[i];
offsetArea = area;
}
if (area > 0)
{
holes.Add(offsets[i]);
}
}
// mark any points that are exact
for (i = 0; i < simple.length; i++)
{
var seg = new NFP();
seg.AddPoint(simple[i]);
seg.AddPoint(simple[i + 1 == simple.length ? 0 : i + 1]);
var index1 = find(seg[0], polygon);
var index2 = find(seg[1], polygon);
if (index1 + 1 == index2 || index2 + 1 == index1 || (index1 == 0 && index2 == polygon.length - 1) || (index2 == 0 && index1 == polygon.length - 1))
{
seg[0].exact = true;
seg[1].exact = true;
}
}
var numshells = 4;
NFP[] shells = new NFP[numshells];
for (j = 1; j < numshells; j++)
{
var delta = j * (tolerance / numshells);
delta = inside ? -delta : delta;
var shell = polygonOffsetDeepNest(simple, delta);
if (shell.Count() > 0)
{
shells[j] = shell.First();
}
else
{
//shells[j] = shell;
}
}
if (offset == null)
{
return(polygon);
}
// selective reversal of offset
for (i = 0; i < offset.length; i++)
{
var o = offset[i];
var target = getTarget(o, simple, 2 * tolerance);
// reverse point offset and try to find exterior points
var test = clone(offset);
test.Points[i] = new SvgPoint(target.x, target.y);
if (!exterior(test, polygon, inside))
{
o.x = target.x;
o.y = target.y;
}
else
{
// a shell is an intermediate offset between simple and offset
for (j = 1; j < numshells; j++)
{
if (shells[j] != null)
{
var shell = shells[j];
var delta = j * (tolerance / numshells);
target = getTarget(o, shell, 2 * delta);
test = clone(offset);
test.Points[i] = new SvgPoint(target.x, target.y);
if (!exterior(test, polygon, inside))
{
o.x = target.x;
o.y = target.y;
break;
}
}
}
}
}
// straighten long lines
// a rounded rectangle would still have issues at this point, as the long sides won't line up straight
var straightened = false;
for (i = 0; i < offset.length; i++)
{
var p1 = offset[i];
var p2 = offset[i + 1 == offset.length ? 0 : i + 1];
var sqd = (p2.x - p1.x) * (p2.x - p1.x) + (p2.y - p1.y) * (p2.y - p1.y);
if (sqd < fixedTolerance)
{
continue;
}
for (j = 0; j < simple.length; j++)
{
var s1 = simple[j];
var s2 = simple[j + 1 == simple.length ? 0 : j + 1];
var sqds = (p2.x - p1.x) * (p2.x - p1.x) + (p2.y - p1.y) * (p2.y - p1.y);
if (sqds < fixedTolerance)
{
continue;
}
if ((GeometryUtil._almostEqual(s1.x, s2.x) || GeometryUtil._almostEqual(s1.y, s2.y)) && // we only really care about vertical and horizontal lines
GeometryUtil._withinDistance(p1, s1, 2 * tolerance) &&
GeometryUtil._withinDistance(p2, s2, 2 * tolerance) &&
(!GeometryUtil._withinDistance(p1, s1, Config.curveTolerance / 1000) ||
!GeometryUtil._withinDistance(p2, s2, Config.curveTolerance / 1000)))
{
p1.x = s1.x;
p1.y = s1.y;
p2.x = s2.x;
p2.y = s2.y;
straightened = true;
}
}
}
//if(straightened){
var Ac = _Clipper.ScaleUpPaths(offset, 10000000);
var Bc = _Clipper.ScaleUpPaths(polygon, 10000000);
var combined = new List <List <IntPoint> >();
var clipper = new ClipperLib.Clipper();
clipper.AddPath(Ac.ToList(), ClipperLib.PolyType.ptSubject, true);
clipper.AddPath(Bc.ToList(), ClipperLib.PolyType.ptSubject, true);
// the line straightening may have made the offset smaller than the simplified
if (clipper.Execute(ClipperLib.ClipType.ctUnion, combined, ClipperLib.PolyFillType.pftNonZero, ClipperLib.PolyFillType.pftNonZero))
{
double?largestArea = null;
for (i = 0; i < combined.Count; i++)
{
var n = Background.toNestCoordinates(combined[i].ToArray(), 10000000);
var sarea = -GeometryUtil.polygonArea(n);
if (largestArea == null || largestArea < sarea)
{
offset = n;
largestArea = sarea;
}
}
}
//}
cleaned = cleanPolygon2(offset);
if (cleaned != null && cleaned.length > 1)
{
offset = cleaned;
}
// mark any points that are exact (for line merge detection)
for (i = 0; i < offset.length; i++)
{
var seg = new SvgPoint[] { offset[i], offset[i + 1 == offset.length ? 0 : i + 1] };
var index1 = find(seg[0], polygon);
var index2 = find(seg[1], polygon);
if (index1 == null)
{
index1 = 0;
}
if (index2 == null)
{
index2 = 0;
}
if (index1 + 1 == index2 || index2 + 1 == index1 ||
(index1 == 0 && index2 == polygon.length - 1) ||
(index2 == 0 && index1 == polygon.length - 1))
{
seg[0].exact = true;
seg[1].exact = true;
}
}
if (!inside && holes != null && holes.Count > 0)
{
offset.children = holes;
}
return(offset);
}
