Added tet-quality mesh adaptor criterion.

Author: SteveMaas1978

FEAMR/FEAMR.cpp

@@ -38,6 +38,7 @@ SOFTWARE.*/
 #include "FEFilterAdaptorCriterion.h"
 #include "FEDomainErrorCriterion.h"
 #include "FEElementDataCriterion.h"
+#include "FETetQualityCriterion.h"
 
 //-----------------------------------------------------------------------------
 void FEAMR::InitModule()
@@ -57,4 +58,5 @@ REGISTER_FECORE_CLASS(FEScaleAdaptorCriterion    , "math");
 REGISTER_FECORE_CLASS(FEMinMaxFilterAdaptorCriterion, "min-max filter");
 REGISTER_FECORE_CLASS(FEDomainErrorCriterion, "relative error");
 REGISTER_FECORE_CLASS(FEElementDataCriterion, "element data");
+REGISTER_FECORE_CLASS(FETetQualityCriterion, "tet-quality");
 }

FEAMR/FETetQualityCriterion.cpp

@@ -0,0 +1,89 @@
+/*This file is part of the FEBio source code and is licensed under the MIT license
+listed below.
+
+See Copyright-FEBio.txt for details.
+
+Copyright (c) 2026 University of Utah, The Trustees of Columbia University in
+the City of New York, and others.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.*/
+#include "FETetQualityCriterion.h"
+#include <FECore/FEElement.h>
+#include <FECore/FEModel.h>
+
+BEGIN_FECORE_CLASS(FETetQualityCriterion, FEMeshAdaptorCriterion)
+	ADD_PARAMETER(minQuality, "min_quality")->setLongName("Minimum tet quality");
+END_FECORE_CLASS();
+
+FETetQualityCriterion::FETetQualityCriterion(FEModel* fem) : FEMeshAdaptorCriterion(fem)
+{
+	minQuality = 0.0;
+}
+
+bool FETetQualityCriterion::GetElementValue(FEElement& el, double& value)
+{
+	if (el.Shape() != ET_TET4) return false;
+	value = TetQuality(el);
+	return (value >= minQuality);
+}
+
+double FETetQualityCriterion::TetQuality(FEElement& el)
+{
+	FEModel* fem = GetFEModel();
+	FEMesh& mesh = fem->GetMesh();
+
+	// get the tet's nodal coordinates
+	vec3d p[4];
+	for (int i = 0; i < 4; ++i) p[i] = mesh.Node(el.m_node[i]).m_rt;
+
+	// setup system of equation
+	mat3d A;
+	A[0][0] = p[1].x - p[0].x; A[0][1] = p[1].y - p[0].y; A[0][2] = p[1].z - p[0].z;
+	A[1][0] = p[2].x - p[0].x; A[1][1] = p[2].y - p[0].y; A[1][2] = p[2].z - p[0].z;
+	A[2][0] = p[3].x - p[0].x; A[2][1] = p[3].y - p[0].y; A[2][2] = p[3].z - p[0].z;
+	A = A.inverse();
+
+	// setup RHS
+	vec3d b;
+	b.x = 0.5 * (p[1].x * p[1].x - p[0].x * p[0].x + p[1].y * p[1].y - p[0].y * p[0].y + p[1].z * p[1].z - p[0].z * p[0].z);
+	b.y = 0.5 * (p[2].x * p[2].x - p[0].x * p[0].x + p[2].y * p[2].y - p[0].y * p[0].y + p[2].z * p[2].z - p[0].z * p[0].z);
+	b.z = 0.5 * (p[3].x * p[3].x - p[0].x * p[0].x + p[3].y * p[3].y - p[0].y * p[0].y + p[3].z * p[3].z - p[0].z * p[0].z);
+
+	// find the center of the circum sphere
+	vec3d c = A * b;
+
+	// find the radius of the circum sphere
+	double R2 = (p[0].x - c.x) * (p[0].x - c.x) + (p[0].y - c.y) * (p[0].y - c.y) + (p[0].z - c.z) * (p[0].z - c.z);
+	double R = sqrt(R2);
+
+	// find the shortest edge
+	const int ET[6][2] = { { 0, 1 }, { 1, 2 }, { 2, 0 }, { 0, 3 }, { 1, 3 }, { 2, 3 } };
+
+	double L2, L2min = 1e99;
+	for (int i = 0; i < 6; ++i)
+	{
+		int j = ET[i][0];
+		int k = ET[i][1];
+		L2 = (p[j].x - p[k].x) * (p[j].x - p[k].x) + (p[j].y - p[k].y) * (p[j].y - p[k].y) + (p[j].z - p[k].z) * (p[j].z - p[k].z);
+		if (L2 < L2min) L2min = L2;
+	}
+	double L = sqrt(L2min);
+
+	return R / L;
+}

FEAMR/FETetQualityCriterion.h

@@ -0,0 +1,44 @@
+/*This file is part of the FEBio source code and is licensed under the MIT license
+listed below.
+
+See Copyright-FEBio.txt for details.
+
+Copyright (c) 2026 University of Utah, The Trustees of Columbia University in
+the City of New York, and others.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.*/
+#pragma once
+#include <FECore/FEMeshAdaptorCriterion.h>
+
+class FETetQualityCriterion : public FEMeshAdaptorCriterion
+{
+public:
+	FETetQualityCriterion(FEModel* fem);
+
+	bool GetElementValue(FEElement& el, double& value) override;
+
+private:
+	double TetQuality(FEElement& el);
+
+private:
+	double minQuality = 0.0;
+
+	DECLARE_FECORE_CLASS()
+};
+