public void TestEquilateralTriangles()
{
double sqrt3 = Math.Sqrt(3);
var vertices = new List <Vertex>()
{
new Vertex(0.0, 0.0)
{
ID = 0
},
new Vertex(1.0, sqrt3)
{
ID = 1
},
new Vertex(2.0, 0.0)
{
ID = 2
},
new Vertex(3.0, sqrt3)
{
ID = 3
}
};
var mesh = new Dwyer().Triangulate(vertices, new Configuration());
var quality = new QualityMeasure(mesh);
Assert.AreEqual(quality.AreaMinimum, quality.AreaMaximum);
Assert.AreEqual(1.0, quality.AlphaMinimum);
Assert.AreEqual(1.0, quality.AlphaMaximum);
Assert.AreEqual(1.0, quality.Q_Minimum);
Assert.AreEqual(1.0, quality.Q_Maximum);
}
public void HandleMeshChange(Mesh mesh)
{
// New mesh stats
lbNumVert.Text = statistic.Vertices.ToString();
lbNumSeg.Text = statistic.ConstrainedEdges.ToString();
lbNumTri.Text = statistic.Triangles.ToString();
// Update statistics tab
angleHistogram1.SetData(statistic.MinAngleHistogram, statistic.MaxAngleHistogram);
lbAreaMin.Text = Util.DoubleToString(statistic.SmallestArea);
lbAreaMax.Text = Util.DoubleToString(statistic.LargestArea);
lbEdgeMin.Text = Util.DoubleToString(statistic.ShortestEdge);
lbEdgeMax.Text = Util.DoubleToString(statistic.LongestEdge);
lbAngleMin.Text = Util.AngleToString(statistic.SmallestAngle);
lbAngleMax.Text = Util.AngleToString(statistic.LargestAngle);
// Update quality
if (quality == null)
{
quality = new QualityMeasure();
}
quality.Update(mesh);
lbQualAlphaMin.Text = Util.DoubleToString(quality.AlphaMinimum);
lbQualAlphaAve.Text = Util.DoubleToString(quality.AlphaAverage);
lbQualAspectMin.Text = Util.DoubleToString(quality.Q_Minimum);
lbQualAspectAve.Text = Util.DoubleToString(quality.Q_Average);
}
public static bool Run(bool print = false)
{
// Generate mesh.
var mesh = CreateMesh();
// The ideal area if triangles were equilateral.
var area = Math.Sqrt(3) / 4 * h * h;
var quality = new QualityMeasure(mesh);
if (print)
{
Console.WriteLine($" Ideal area: {area}");
Console.WriteLine($" Min. area: {quality.AreaMinimum}");
Console.WriteLine($" Max. area: {quality.AreaMaximum}");
Console.WriteLine($" Avg. area: {quality.AreaTotal / mesh.Triangles.Count}");
SvgImage.Save(mesh, "example-4.svg", 500);
}
return(quality.AreaMinimum < area && quality.AreaMaximum > area);
}
public static Mesh RefineRegions()
{
// Generate the input geometry.
var poly = new Polygon();
var center = new Point(0, 0);
// Three concentric circles.
poly.Add(Example2.Circle(1.0, center, 0.1, 1), center);
poly.Add(Example2.Circle(2.0, center, 0.1, 2));
poly.Add(Example2.Circle(3.0, center, 0.3, 3));
// Define regions.
poly.Regions.Add(new RegionPointer(1.5, 0.0, 1));
poly.Regions.Add(new RegionPointer(2.5, 0.0, 2));
// Set quality and constraint options.
var options = new ConstraintOptions()
{
ConformingDelaunay = true
};
var quality = new QualityOptions()
{
MinimumAngle = 25.0
};
// Generate mesh.
var mesh = (Mesh)poly.Triangulate(options, quality);
var smoother = new SimpleSmoother();
// Smooth mesh and re-apply quality options.
smoother.Smooth(mesh);
mesh.Refine(quality);
// Calculate mesh quality
var statistic = new QualityMeasure();
statistic.Update(mesh);
// Use the minimum triangle area for region refinement
double area = 1.75 * statistic.AreaMinimum;
foreach (var t in mesh.Triangles)
{
// Set area constraint for all triangles in region 1
if (t.Label == 1)
{
t.Area = area;
}
}
// Use per triangle area constraint for next refinement
quality.VariableArea = true;
// Refine mesh to meet area constraint.
mesh.Refine(quality);
// Smooth once again.
smoother.Smooth(mesh);
return(mesh);
}
