GenericParameters

GenericParameters is a C++ header-only library to define generic parameters. A generic parameter can be defined by a pointer to a variable or by set/get-functions. Moreover, a generic parameter stores additional information like the parameter type, max/min limits, a description, etc. Such parameters are very useful, e.g., for an automatic generation of GUI elements.

The library is used in SPlisHSPlasH to handle all parameters of the implemented fluid simulation methods.

Author: Jan Bender, License: MIT

Libraries using GenericParameters

• SPlisHSPlasH - A C++ library for the physically-based simulation of fluids using Smoothed Particle Hydrodynamics
• PBD - A C++ library for physically-based simulation of rigid bodies, deformables, cloth and fluids using Position-Based Dynamics (Coming soon)

Build Instructions

Since this is a header-only library, the build is only required for the tests.

This project is based on CMake. Simply generate project, Makefiles, etc. using CMake and compile the project with the compiler of your choice. The code was tested with the following configurations:

• Windows 10 64-bit, CMake 3.7, Visual Studio 2015 & 2017
• Debian 8 64-bit, CMake 3.7, GCC 4.9.2.

Usage

Creating a generic parameter for an integer value by providing the pointer of an integer variable:

m_intValue = 3;
MY_INT_PARAMETER = createNumericParameter("intParam", "Int param", &m_intValue);
setGroup(MY_INT_PARAMETER, "ParameterGroup");
setDescription(MY_INT_PARAMETER, "Help text");

// Set min and max values
IntParameter* intParam = static_cast<IntParameter*>(getParameter(MY_INT_PARAMETER));
intParam->setMinValue(2);
intParam->setMaxValue(4);

The function createNumericParameter returns an integer id of the parameter which can be used to set/get values or to get information about the parameter. The value of a generic parameter can be set/get by the unified functions getValue/setValue:

getValue<int>(TestParameterObject::MY_INT_PARAMETER);
setValue<int>(TestParameterObject::MY_INT_PARAMETER, -5);

Moreover, you can query the type of any parameter:

if (getType(TestParameterObject::MY_INT_PARAMETER) == ParameterBase::INT32)

In the following an example for an enum parameter is given:

m_enumValue = 1;
MY_ENUM_PARAMETER = createEnumParameter("enumParam", "Enum param", &m_enumValue);
EnumParameter* enumParam = static_cast<EnumParameter*>(getParameter(MY_ENUM_PARAMETER));
enumParam->addEnumValue("enum1", MY_ENUM_VALUE1);
enumParam->addEnumValue("enum2", MY_ENUM_VALUE2);
enumParam->setGroup("EnumGroup");
enumParam->setDescription("This is an enum.");

Here, the integers MY_ENUM_VALUE1 and MY_ENUM_VALUE2 are set in the function addEnumValue() defining an id for the corresponding enum value.

Another example which uses get/set callback functions instead of a pointer to a variable is given here:

// header
double getDoubleValue() { return m_doubleValue; }
void setDoubleValue(double val) { m_doubleValue = val; }

// implementation
setDoubleValue(3.123);
ParameterBase::GetFunc<double> getFct = std::bind(&TestParameterObject::getDoubleValue, this);
ParameterBase::SetFunc<double> setFct = std::bind(&TestParameterObject::setDoubleValue, this, std::placeholders::_1);
MY_DOUBLE_PARAMETER = createNumericParameter<double>("doubleParam", "Double param", getFct, setFct);
setGroup(MY_DOUBLE_PARAMETER, "ParameterGroup");
setDescription(MY_DOUBLE_PARAMETER, "Help text");
DoubleParameter* doubleParam = static_cast<DoubleParameter*>(getParameter(MY_DOUBLE_PARAMETER));
doubleParam->setMinValue(0.1);
doubleParam->setMaxValue(0.9);