Core Engine The core engine module, including lifecycle management, simulation options, and shared utilities.

Collaboration diagram for Core Engine The core engine module, including lifecycle management, simulation options, and shared utilities.:

Files
file	charconv_compat.hpp
	Portable from_chars for floating-point types.
file	Constants.hpp
	Global physical, numerical, and model constants for OpenSWMM Engine.
file	DateTime.hpp
	DateTime utility functions — numerically identical to legacy datetime.c.
file	ErrorCodes.cpp
	Error/warning description table and formatting — legacy-compatible.
file	ErrorCodes.hpp
	Legacy-compatible error and warning codes with description lookup.
file	FileIO.hpp
	Opening files by UTF-8 path on every platform.
file	FilePathPair.hpp
	Carrier for an external file reference in a SWMM model.
file	InpWriter.cpp
	Comprehensive .inp serialisation — round-trip identical output.
file	InpWriter.hpp
	Write a SimulationContext to a SWMM .inp file.
file	InterfaceFile.cpp
	Routing interface file — coupling between separate SWMM simulations.
file	InterfaceFile.hpp
	Routing interface file — coupling between separate SWMM simulations.
file	NodeCoupling2D.cpp
	[2D_NODE_COUPLING] tokens, class defaults, validation, section handler and row formatting.
file	NodeCoupling2D.hpp
	[2D_NODE_COUPLING]: per-node coupling type — tokens, class defaults, validation, input section and row formatting.
file	PathResolver.hpp
	Pure-function path normalisation and relative-path math.
file	SimulationContext.hpp
	The central, reentrant simulation context for the new engine.
file	SpatialFrame.hpp
	Spatial frame — CRS specification and coordinate data for nodes/links.
file	StringCase.hpp
	Case-insensitive string helpers matching legacy SWMM name semantics.
file	TypeHelpers.hpp
	Shared C↔internal type mapping utilities for node and link type enums.
file	UnitConversion.cpp
	Global unit conversion — matching legacy SWMM UCF().
file	UnitConversion.hpp
	Global unit conversion factors — matching legacy SWMM Ucf[]/Qcf[].
file	UserFlags.hpp
	User-defined model flags (InfoWorks ICM-style, two-section design).

Classes
struct	openswmm::PluginSpec
	One plugin entry from the [PLUGINS] section. More...
struct	openswmm::HotstartSaveEntry
	Configuration parsed from the [FILES] section. More...
struct	openswmm::StateAccessors
	Solver-neutral hooks for reading and writing solver-internal state (infiltration, groundwater) at hot-start save/load time. More...
struct	openswmm::SimulationContext
	Central, reentrant simulation context. More...
struct	openswmm::SimulationOptions
	All SWMM simulation options parsed from [OPTIONS] section. More...
class	openswmm::ICouplingPoint
	Abstract coupling point between a 1D SWMM object and a 2D mesh cell. More...
struct	openswmm::SpatialFrame
	Spatial frame containing CRS and georeferenced coordinates. More...
struct	openswmm::UserFlagDef
	Schema entry for a single user-defined flag. More...
struct	openswmm::UserFlagAssignment
	A (object_type, object_name, flag_name) → value assignment. More...
class	openswmm::UserFlags
	Stores the full user-flags data: schema definitions + per-object values. More...

Typedefs
using	openswmm::UserFlagValue = std::variant<bool, int, double, std::string>
	A concrete flag value assigned to a specific object.

Enumerations
enum class	openswmm::FileMode {   openswmm::FileMode::NONE ,   openswmm::FileMode::SAVE ,   openswmm::FileMode::USE }
	Mode keyword for one [FILES] row — SAVE or USE. More...
enum class	openswmm::EngineState : int32_t {   openswmm::EngineState::CREATED = 0 ,   openswmm::EngineState::OPENED = 1 ,   openswmm::EngineState::INITIALIZED = 2 ,   openswmm::EngineState::RUNNING = 3 ,   openswmm::EngineState::PAUSED = 4 ,   openswmm::EngineState::ENDED = 5 ,   openswmm::EngineState::REPORTED = 6 ,   openswmm::EngineState::CLOSED = 7 ,   openswmm::EngineState::ERROR_STATE = 8 ,   openswmm::EngineState::BUILDING = 9 }
	High-level engine lifecycle state. More...
enum class	openswmm::UserFlagType : int {   openswmm::UserFlagType::BOOLEAN = 0 ,   openswmm::UserFlagType::INTEGER = 1 ,   openswmm::UserFlagType::REAL = 2 ,   openswmm::UserFlagType::STRING = 3 }
	Value type for a user flag. More...

Detailed Description

Typedef Documentation

UserFlagValue

using openswmm::UserFlagValue = std::variant<bool, int, double, std::string>

A concrete flag value assigned to a specific object.

Enumeration Type Documentation

EngineState

enum class openswmm::EngineState : int32_t

strong

High-level engine lifecycle state.

Mirrors SWMM_EngineState in include/openswmm/engine/openswmm_engine.h but lives in the C++ domain (scoped enum).

Enumerator
CREATED	Context allocated, no input loaded.
OPENED	Input file parsed, objects allocated.
INITIALIZED	Initial conditions applied.
RUNNING	Simulation loop in progress.
PAUSED	Simulation paused (future hot-swap support)
ENDED	Simulation loop completed.
REPORTED	Summary report written.
CLOSED	Resources released.
ERROR_STATE	Fatal error; call swmm_engine_last_error()
BUILDING	Programmatic model construction in progress (no .inp)

FileMode

enum class openswmm::FileMode

strong

Mode keyword for one [FILES] row — SAVE or USE.

NONE is the in-memory default for unconfigured slots so the writer can skip them. SAVE writes data out at simulation end; USE reads data in at simulation start.

Enumerator
NONE
SAVE
USE

UserFlagType

enum class openswmm::UserFlagType : int

strong

Value type for a user flag.

Enumerator
BOOLEAN	YES/NO/TRUE/FALSE/1/0.
INTEGER	Signed integer.
REAL	Double-precision floating-point.
STRING	Arbitrary string.