SimulationContext.hpp File Reference

The central, reentrant simulation context for the new engine. More...

#include "../data/GageData.hpp"
#include "../data/LinkData.hpp"
#include "../data/NameIndex.hpp"
#include "../data/NodeData.hpp"
#include "../data/PollutantData.hpp"
#include "../data/SubcatchData.hpp"
#include "../data/TableData.hpp"
#include "SimulationOptions.hpp"
#include "SpatialFrame.hpp"
#include "UserFlags.hpp"
#include "../data/QualityData.hpp"
#include "../data/InflowData.hpp"
#include "../data/InfraData.hpp"
#include "../data/HydrologyData.hpp"
#include "../data/ForcingData.hpp"
#include <algorithm>
#include <cstdint>
#include <string>
#include <vector>

Include dependency graph for SimulationContext.hpp:

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Classes
struct	openswmm::PluginSpec
	One plugin entry from the [PLUGINS] section. More...
struct	openswmm::SimulationContext
	Central, reentrant simulation context. More...
struct	openswmm::SimulationContext::MassBalance
	Cumulative mass balance totals for runoff and routing. More...
struct	openswmm::SimulationContext::RoutingStepStats

Namespaces
namespace	openswmm

Enumerations
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...

Detailed Description

The central, reentrant simulation context for the new engine.

SimulationContext is the single owner of all simulation state. It replaces the ~70 global variables in src/solver/globals.h with a value type that is thread-safe (one context per thread) and trivially clonable for parallel runs.

Architecture summary

Legacy (globals.h)	New location
FlowUnits, RouteModel, …	ctx.options (SimulationOptions)
StartDate, EndDate, ElapsedTime, …	ctx.current_time, ctx.options.*
Node[], Nnodes[]	ctx.nodes (NodeData) + ctx.node_names (NameIndex)
Link[], Nlinks[]	ctx.links (LinkData) + ctx.link_names (NameIndex)
Subcatch[], Nsubcatch	ctx.subcatches (SubcatchData) + ctx.subcatch_names
Gage[], Ngages	ctx.gages (GageData) + ctx.gage_names
Pollut[], Npolluts + quality state	ctx.pollutants (PollutantData)
Tseries[] / Curve[]	ctx.tables (TableData) + ctx.table_names
Coord[]	ctx.spatial (SpatialFrame)
— (new)	ctx.user_flags (UserFlags)

Lifecycle

ctx.reset()          — full cold reset (call before re-running)
ctx.save_state()     — snapshot current state into old-step arrays
ctx.advance(dt)      — advance simulation clock by dt seconds
ctx.output_due()     — true when dt_output_remaining <= EPSILON
ctx.is_complete()    — true when current_time >= end_time

Thread safety

A SimulationContext must not be shared between threads without external synchronization. The IO thread receives a deep copy (SimulationSnapshot) posted through the ring queue — not a pointer to the live context.

See also

Legacy reference: src/solver/globals.h

src/engine/data/NodeData.hpp

src/engine/data/LinkData.hpp

src/engine/data/SubcatchData.hpp

src/engine/data/GageData.hpp

src/engine/data/PollutantData.hpp

src/engine/data/TableData.hpp

src/engine/data/NameIndex.hpp

src/engine/core/SimulationOptions.hpp

src/engine/core/SpatialFrame.hpp

src/engine/core/UserFlags.hpp

include/openswmm/plugin_sdk/SimulationSnapshot.hpp

Author

Caleb Buahin caleb.nosp@m..bua.nosp@m.hin@g.nosp@m.mail.nosp@m..com

Copyright

Copyright (c) 2026 HydroCouple. All rights reserved.

License\n MIT License