/// <summary>
/// Triangulate this solid and pack the triangulated data into buffers
/// appropriate for use with gltf.
/// </summary>
public GraphicsBuffers Tessellate()
{
var tessellations = new Tess[this.Faces.Count];
var fi = 0;
foreach (var f in this.Faces.Values)
{
var tess = new Tess();
tess.NoEmptyPolygons = true;
tess.AddContour(f.Outer.ToContourVertexArray(f));
if (f.Inner != null)
{
foreach (var loop in f.Inner)
{
tess.AddContour(loop.ToContourVertexArray(f));
}
}
tess.Tessellate(WindingRule.Positive, LibTessDotNet.Double.ElementType.Polygons, 3);
tessellations[fi] = tess;
fi++;
}
var buffers = new GraphicsBuffers();
var iCursor = 0;
var imax = int.MinValue;
for (var i = 0; i < tessellations.Length; i++)
{
var tess = tessellations[i];
var a = tess.Vertices[tess.Elements[0]].Position.ToVector3();
var b = tess.Vertices[tess.Elements[1]].Position.ToVector3();
var c = tess.Vertices[tess.Elements[2]].Position.ToVector3();
var n = (b - a).Cross(c - a).Unitized();
for (var j = 0; j < tess.Vertices.Length; j++)
{
var v = tess.Vertices[j];
buffers.AddVertex(v.Position.ToVector3(), n, new UV());
}
for (var k = 0; k < tess.Elements.Length; k++)
{
var t = tess.Elements[k];
var index = (ushort)(t + iCursor);
buffers.AddIndex(index);
imax = Math.Max(imax, index);
}
iCursor = imax + 1;
}
return(buffers);
}
internal GraphicsBuffers ToGraphicsBuffers()
{
var gb = new GraphicsBuffers();
for (var i = 0; i < this.Locations.Count; i++)
{
var l = this.Locations[i];
gb.AddVertex(l, default(Vector3), default(UV), null);
gb.AddIndex((ushort)(i));
}
return(gb);
}
