public void Build(List <Polygon> polygons)
{
if (polygons.Count == 0)
{
return;
}
if (Plane == null)
{
Plane = polygons[0].Plane.Clone();
}
var pp = Plane.ToPrecisionPlane();
var front = new List <Polygon>();
var back = new List <Polygon>();
foreach (var polygon in polygons.Select(x => x.ToPrecisionPolygon()))
{
polygon.Split(pp, out var b, out var f, out var cb, out var cf);
if (f != null)
{
front.Add(f.ToStandardPolygon());
}
if (b != null)
{
back.Add(b.ToStandardPolygon());
}
if (cf != null)
{
front.Add(cf.ToStandardPolygon());
}
if (cb != null)
{
back.Add(cb.ToStandardPolygon());
}
}
if (front.Count > 0)
{
if (Front == null)
{
Front = new CsgNode();
}
Front.Build(front);
}
if (back.Count > 0)
{
if (Back == null)
{
Back = new CsgNode();
}
Back.Build(back);
}
}
private List <Polygon> ClipPolygons(IEnumerable <Polygon> polygons)
{
if (Plane == null)
{
return(polygons.ToList());
}
var pp = Plane.ToPrecisionPlane();
var front = new List <Polygon>();
var back = new List <Polygon>();
foreach (var polygon in polygons.Select(x => x.ToPrecisionPolygon()))
{
polygon.Split(pp, out var b, out var f, out var cb, out var cf);
if (f != null)
{
front.Add(f.ToStandardPolygon());
}
if (b != null)
{
back.Add(b.ToStandardPolygon());
}
if (cf != null)
{
front.Add(cf.ToStandardPolygon());
}
if (cb != null)
{
back.Add(cb.ToStandardPolygon());
}
}
if (Front != null)
{
front = Front.ClipPolygons(front);
}
back = Back != null?Back.ClipPolygons(back) : new List <Polygon>();
return(front.Concat(back).ToList());
}
protected override void Render(MapDocument document, BufferBuilder builder, ResourceCollector resourceCollector)
{
base.Render(document, builder, resourceCollector);
if (_state != ClipState.None && _clipPlanePoint1 != null && _clipPlanePoint2 != null && _clipPlanePoint3 != null)
{
// Draw the lines
var p1 = _clipPlanePoint1.Value;
var p2 = _clipPlanePoint2.Value;
var p3 = _clipPlanePoint3.Value;
builder.Append(
new []
{
new VertexStandard {
Position = p1, Colour = Vector4.One, Tint = Vector4.One
},
new VertexStandard {
Position = p2, Colour = Vector4.One, Tint = Vector4.One
},
new VertexStandard {
Position = p3, Colour = Vector4.One, Tint = Vector4.One
},
},
new uint [] { 0, 1, 1, 2, 2, 0 },
new []
{
new BufferGroup(PipelineType.Wireframe, CameraType.Both, 0, 6)
}
);
if (!p1.EquivalentTo(p2) &&
!p2.EquivalentTo(p3) &&
!p1.EquivalentTo(p3) &&
!document.Selection.IsEmpty)
{
var plane = new Plane(p1, p2, p3);
var pp = plane.ToPrecisionPlane();
// Draw the clipped solids
var faces = new List <Polygon>();
foreach (var solid in document.Selection.OfType <Solid>().ToList())
{
var s = solid.ToPolyhedron().ToPrecisionPolyhedron();
s.Split(pp, out var back, out var front);
if (_side != ClipSide.Front && back != null)
{
faces.AddRange(back.Polygons.Select(x => x.ToStandardPolygon()));
}
if (_side != ClipSide.Back && front != null)
{
faces.AddRange(front.Polygons.Select(x => x.ToStandardPolygon()));
}
}
var verts = new List <VertexStandard>();
var indices = new List <int>();
foreach (var polygon in faces)
{
var c = verts.Count;
verts.AddRange(polygon.Vertices.Select(x => new VertexStandard {
Position = x, Colour = Vector4.One, Tint = Vector4.One
}));
for (var i = 0; i < polygon.Vertices.Count; i++)
{
indices.Add(c + i);
indices.Add(c + (i + 1) % polygon.Vertices.Count);
}
}
builder.Append(
verts, indices.Select(x => (uint)x),
new[] { new BufferGroup(PipelineType.Wireframe, CameraType.Both, 0, (uint)indices.Count) }
);
// Draw the clipping plane
var poly = new DataStructures.Geometric.Precision.Polygon(pp);
var bbox = document.Selection.GetSelectionBoundingBox();
var point = bbox.Center;
foreach (var boxPlane in bbox.GetBoxPlanes())
{
var proj = boxPlane.Project(point);
var dist = (point - proj).Length() * 0.1f;
var pln = new Plane(boxPlane.Normal, proj + boxPlane.Normal * Math.Max(dist, 100)).ToPrecisionPlane();
if (poly.Split(pln, out var b, out _))
{
poly = b;
}
}
verts.Clear();
indices.Clear();
var clipPoly = poly.ToStandardPolygon();
var colour = Color.FromArgb(64, Color.Turquoise).ToVector4();
// Add the face in both directions so it renders on both sides
var polies = new[] { clipPoly.Vertices.ToList(), clipPoly.Vertices.Reverse().ToList() };
foreach (var p in polies)
{
var offs = verts.Count;
verts.AddRange(p.Select(x => new VertexStandard
{
Position = x,
Colour = Vector4.One,
Tint = colour,
Flags = VertexFlags.FlatColour
}));
for (var i = 2; i < clipPoly.Vertices.Count; i++)
{
indices.Add(offs);
indices.Add(offs + i - 1);
indices.Add(offs + i);
}
}
builder.Append(
verts, indices.Select(x => (uint)x),
new[] { new BufferGroup(PipelineType.TexturedAlpha, CameraType.Perspective, p1, 0, (uint)indices.Count) }
);
}
}
}
/// <summary>
/// Creates a polygon from a plane and a radius.
/// Expands the plane to the radius size to create a large polygon with 4 vertices.
/// This constructor uses high-precision operations.
/// </summary>
/// <param name="plane">The polygon plane</param>
/// <param name="radius">The polygon radius</param>
public Polygon(Plane plane, float radius = 100000f)
{
Vertices = new Precision.Polygon(plane.ToPrecisionPlane(), radius).Vertices.Select(x => x.ToStandardVector3()).ToList();
}