internal List <Polygon> PolygonOperationWith(Polygon p, PolygonOperationType type)
{
if (!IsSimple || !p.IsSimple)
{
throw new PolygonException("Both polygons must be non-self-intersecting.");
}
Geometry resultPolys;
switch (type)
{
case PolygonOperationType.Intersection:
resultPolys = p.ToIPolygon().Intersection(ToIPolygon());
break;
case PolygonOperationType.Union:
resultPolys = p.ToIPolygon().Union(ToIPolygon());
break;
case PolygonOperationType.Difference:
resultPolys = p.ToIPolygon().Difference(ToIPolygon());
break;
case PolygonOperationType.SymmetricDifference:
resultPolys = p.ToIPolygon().SymmetricDifference(ToIPolygon()).Buffer(BufferDistance);
break;
default:
throw new PolygonException("Unsupported operation type.");
}
var multiPolygon = resultPolys as MultiPolygon;
var results = new List <Polygon>();
if (multiPolygon != null)
{
results.AddRange(multiPolygon.Geometries.Cast <NetTopologySuite.Geometries.Polygon>().SelectMany(poly => poly.ToElmaPolygons()));
}
if (resultPolys is NetTopologySuite.Geometries.Polygon polygon)
{
results.AddRange(polygon.ToElmaPolygons());
}
foreach (var x in results)
{
x.UpdateDecomposition();
}
return(results);
}
public void KeyDown(KeyEventArgs key)
{
if (key.KeyCode != Keys.Space || FirstSelected)
{
return;
}
switch (_currentOpType)
{
case PolygonOperationType.Union:
_currentOpType = PolygonOperationType.Difference;
break;
case PolygonOperationType.Intersection:
break;
case PolygonOperationType.Difference:
_currentOpType = PolygonOperationType.Union;
break;
}
UpdateHelp();
}
public static bool PolyOpSelected(PolygonOperationType opType, List <Polygon> polygons)
{
var polys = polygons.GetSelectedPolygons().ToList();
Geometry SymDiff(Geometry g, Geometry p) => p.SymmetricDifference(g);
var selection = polygons.GetSelectedPolygonsAsMultiPolygon();
var touching = polygons.Where(p =>
{
if (p.IsGrass)
{
return(false);
}
var ip = p.ToIPolygon();
return(!polys.Contains(p) && ip.Intersects(selection) && !ip.Contains(selection));
}).ToList();
if (!touching.Any())
{
return(false);
}
var others = touching.ToIPolygons().Aggregate((Func <Geometry, Geometry, Geometry>)SymDiff);
var remaining = polygons.Where(p =>
{
if (p.IsGrass)
{
return(false);
}
var ipoly = p.ToIPolygon();
return(!touching.Contains(p) && !polys.Contains(p) && ipoly.Within(others));
}).ToList();
others = remaining.ToIPolygons().Aggregate(others, (Func <Geometry, Geometry, Geometry>)SymDiff);
Geometry result;
try
{
switch (opType)
{
case PolygonOperationType.Union:
result = others.Union(selection);
break;
case PolygonOperationType.Difference:
result = others.Difference(selection);
break;
case PolygonOperationType.Intersection:
result = others.Intersection(selection);
break;
case PolygonOperationType.SymmetricDifference:
result = others.SymmetricDifference(selection)
.Buffer(Polygon.BufferDistance, new BufferParameters(0, EndCapStyle.Flat, JoinStyle.Bevel, 1));
break;
default:
throw new Exception("Unknown operation type.");
}
}
catch (TopologyException)
{
Utils.ShowError(
"Could not perform this operation. Make sure the polygons don't have self-intersections.");
return(false);
}
touching.ForEach(p => polygons.Remove(p));
polys.ForEach(p => polygons.Remove(p));
remaining.ForEach(p => polygons.Remove(p));
switch (result)
{
case MultiPolygon polygon:
{
foreach (var geometry in polygon.Geometries.Cast <NetTopologySuite.Geometries.Polygon>().Where(p => !p.IsEmpty))
{
var newPolys = geometry.ToElmaPolygons().ToList();
newPolys.ForEach(p => p.RemoveDuplicateVertices());
polygons.AddRange(newPolys);
}
break;
}
case NetTopologySuite.Geometries.Polygon polygon1 when !polygon1.IsEmpty:
{
var newPolys = polygon1.ToElmaPolygons().ToList();
newPolys.ForEach(p => p.RemoveDuplicateVertices());
polygons.AddRange(newPolys);
break;
}
}
if (!polygons.Any())
{
Utils.ShowError("The level would become empty after this operation.");
polygons.AddRange(polys);
polygons.AddRange(touching);
}
return(true);
}
