Revision control
++ // Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
++ // Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
++ // SPDX-FileCopyrightText: Copyright (c) 2008-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
++ // SPDX-License-Identifier: Apache-2.0
++
++ #ifndef DY_BIAS_COEFFICIENT_CPUGPU_H
++ #define DY_BIAS_COEFFICIENT_CPUGPU_H
++
++ #include "foundation/PxSimpleTypes.h"
++
++ #include <stdio.h>
++
++
++ namespace physx
++ {
++ namespace Dy
++ {
++
++
++ /**
++ \brief Struct that holds the different bias coefficients used for different devices, features and solvers
++ */
++ struct BiasCoefficientCollection
++ {
++ void set(bool isGPU, bool isTGS, PxU32 nbPositionIterations)
++ {
++ if (isTGS)
++ {
++ const PxReal biasCoefficientBase = PxSqrt(1.0f / nbPositionIterations);
++ const PxReal biasCoefficientBaseTimes2 = 2.0f * biasCoefficientBase;
++
++ rigidContact = PxMin(0.8f, biasCoefficientBaseTimes2);
++ joint = biasCoefficientBase;
++ articulation = PxMin(0.9f, biasCoefficientBaseTimes2);
++
++ if (isGPU)
++ {
++ particle = PxMin(0.9f, biasCoefficientBaseTimes2);
++ deformableRigidAttachment = PxMin(0.9f, biasCoefficientBaseTimes2);
++ }
++ else
++ {
++ // these are GPU only features
++ particle = 0.0f;
++ deformableRigidAttachment = 0.0f;
++ }
++ }
++ else
++ {
++ rigidContact = 0.8f;
++ joint = 1.0f;
++ articulation = 0.8f;
++
++ if (isGPU)
++ {
++ particle = 0.7f;
++ deformableRigidAttachment = 0.5f;
++ }
++ else
++ {
++ // these are GPU only features
++ particle = 0.0f;
++ deformableRigidAttachment = 0.0f;
++ }
++ }
++ }
++
++ // for contact constraints (including articulation contact). Applies to sticky friction bias too.
++ //
++ PxReal rigidContact;
++
++ // for maximal coordinate joints (PxJoint, PxConstraint)
++ //
++ PxReal joint;
++
++ // for articulation internal constraints, mimic joints etc.
++ //
++ PxReal articulation;
++
++ // Bias / under-relaxation for the internal PBD particle solve (GPU).
++ PxReal particle;
++
++ // for FEM deformable (volume + cloth) attachment to rigid bodies (only on GPU).
++ // PGS value (0.5) is the Baumgarte coefficient empirically tuned for cloth-attach
++ // stability: higher values (e.g. 0.7) destabilize low-mass single-vertex
++ // cloth attachments. Volume FEM tolerates higher values but is also fine at 0.5.
++ //
++ PxReal deformableRigidAttachment;
++ };
++
++
++ } //namespace Dy
++ } //namespace physx
++
++
++ #endif //DY_BIAS_COEFFICIENT_CPUGPU_H