p.Chaos.Solver.DebugDrawBVHs
p.Chaos.Solver.DebugDrawBVHs
#Overview
name: p.Chaos.Solver.DebugDrawBVHs
This variable is created as a Console Variable (cvar).
- type:
Var - help:
Draw Particle BVHs where applicable (0 = never; 1 = end of frame).
It is referenced in 4 C++ source files.
#Summary
#Usage in the C++ source code
The purpose of p.Chaos.Solver.DebugDrawBVHs is to enable debug drawing of Particle Bounding Volume Hierarchies (BVHs) in the Chaos physics solver system of Unreal Engine 5. This setting is specifically for debugging and visualization purposes within the physics simulation.
This setting variable is primarily used by the Chaos physics solver, which is part of the Experimental Chaos module in Unreal Engine 5. It’s utilized in the PBDRigidsSolver (Position Based Dynamics Rigid Solver) component of the Chaos system.
The value of this variable is set through the Unreal Engine console variable system. It’s initialized to 0 by default, as seen in the source code:
int32 ChaosSolverDebugDrawBVHs = 0;
The variable interacts with the associated variable ChaosSolverDebugDrawBVHs. They share the same value and are used interchangeably in the code.
Developers should be aware that this is a debug visualization tool and should only be enabled when necessary for debugging purposes. Enabling this feature may impact performance, especially in complex scenes with many physics objects.
Best practices when using this variable include:
- Only enable it when actively debugging physics issues related to BVHs.
- Use it in conjunction with other debug drawing options for a comprehensive view of the physics state.
- Remember to disable it in production builds to avoid performance overhead.
Regarding the associated variable ChaosSolverDebugDrawBVHs:
- It serves the same purpose as p.Chaos.Solver.DebugDrawBVHs.
- It’s used directly in the C++ code to control the debug drawing functionality.
- The value is checked in the PostTickDebugDraw function of the FPBDRigidsSolver class to determine whether to draw the BVHs.
- When set to 1, it triggers the drawing of particle BVHs for non-disabled particles in the solver.
Developers should treat both p.Chaos.Solver.DebugDrawBVHs and ChaosSolverDebugDrawBVHs as the same entity, understanding that changing one will affect the other due to their shared value.
#References in C++ code
#Callsites
This variable is referenced in the following C++ source code:
#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:147
Scope (from outer to inner):
file
namespace Chaos
namespace CVars
Source code excerpt:
FAutoConsoleVariableRef CVarChaosSolverDrawShapes(TEXT("p.Chaos.Solver.DebugDrawShapes"), ChaosSolverDebugDrawShapes, TEXT("Draw Shapes (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDebugDrawMass(TEXT("p.Chaos.Solver.DebugDrawMass"), ChaosSolverDebugDrawMass, TEXT("Draw Mass values in Kg (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawBVHs(TEXT("p.Chaos.Solver.DebugDrawBVHs"), ChaosSolverDebugDrawBVHs, TEXT("Draw Particle BVHs where applicable (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawCollisions(TEXT("p.Chaos.Solver.DebugDrawCollisions"), ChaosSolverDebugDrawCollisions, TEXT("Draw Collisions (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawCollidingShapes(TEXT("p.Chaos.Solver.DebugDrawCollidingShapes"), ChaosSolverDebugDrawCollidingShapes, TEXT("Draw Shapes that have collisions on them (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawBounds(TEXT("p.Chaos.Solver.DebugDrawBounds"), ChaosSolverDebugDrawBounds, TEXT("Draw bounding volumes inside the broadphase (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawTransforms(TEXT("p.Chaos.Solver.DebugDrawTransforms"), ChaosSolverDrawTransforms, TEXT("Draw particle transforms (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawIslands(TEXT("p.Chaos.Solver.DebugDrawIslands"), ChaosSolverDrawIslands, TEXT("Draw solver islands (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawIslandSleepState(TEXT("p.Chaos.Solver.DebugDrawSleepState"), ChaosSolverDebugDrawIslandSleepState, TEXT("Draw island sleep state."));
#Associated Variable and Callsites
This variable is associated with another variable named ChaosSolverDebugDrawBVHs. They share the same value. See the following C++ source code.
#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:120
Scope (from outer to inner):
file
namespace Chaos
namespace CVars
Source code excerpt:
int32 ChaosSolverDebugDrawShapes = CHAOS_SOLVER_ENABLE_DEBUG_DRAW;
int32 ChaosSolverDebugDrawMass = 0;
int32 ChaosSolverDebugDrawBVHs = 0;
int32 ChaosSolverDebugDrawCollisions = CHAOS_SOLVER_ENABLE_DEBUG_DRAW;
int32 ChaosSolverDebugDrawCollidingShapes = 0;
int32 ChaosSolverDebugDrawBounds = 0;
int32 ChaosSolverDrawTransforms = 0;
int32 ChaosSolverDrawIslands = 0;
int32 ChaosSolverDebugDrawIslandSleepState = 0;
#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:147
Scope (from outer to inner):
file
namespace Chaos
namespace CVars
Source code excerpt:
FAutoConsoleVariableRef CVarChaosSolverDrawShapes(TEXT("p.Chaos.Solver.DebugDrawShapes"), ChaosSolverDebugDrawShapes, TEXT("Draw Shapes (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDebugDrawMass(TEXT("p.Chaos.Solver.DebugDrawMass"), ChaosSolverDebugDrawMass, TEXT("Draw Mass values in Kg (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawBVHs(TEXT("p.Chaos.Solver.DebugDrawBVHs"), ChaosSolverDebugDrawBVHs, TEXT("Draw Particle BVHs where applicable (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawCollisions(TEXT("p.Chaos.Solver.DebugDrawCollisions"), ChaosSolverDebugDrawCollisions, TEXT("Draw Collisions (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawCollidingShapes(TEXT("p.Chaos.Solver.DebugDrawCollidingShapes"), ChaosSolverDebugDrawCollidingShapes, TEXT("Draw Shapes that have collisions on them (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawBounds(TEXT("p.Chaos.Solver.DebugDrawBounds"), ChaosSolverDebugDrawBounds, TEXT("Draw bounding volumes inside the broadphase (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawTransforms(TEXT("p.Chaos.Solver.DebugDrawTransforms"), ChaosSolverDrawTransforms, TEXT("Draw particle transforms (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawIslands(TEXT("p.Chaos.Solver.DebugDrawIslands"), ChaosSolverDrawIslands, TEXT("Draw solver islands (0 = never; 1 = end of frame)."));
FAutoConsoleVariableRef CVarChaosSolverDrawIslandSleepState(TEXT("p.Chaos.Solver.DebugDrawSleepState"), ChaosSolverDebugDrawIslandSleepState, TEXT("Draw island sleep state."));
#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:2562
Scope (from outer to inner):
file
namespace Chaos
function void FPBDRigidsSolver::PostTickDebugDraw
Source code excerpt:
DebugDraw::DrawParticleMass(FRigidTransform3(), Particles.GetNonDisabledDynamicView(), &ChaosSolverDebugDebugDrawSettings);
}
if (ChaosSolverDebugDrawBVHs == 1)
{
for (const FTransientGeometryParticleHandle& Particle : Particles.GetNonDisabledView())
{
DebugDraw::DrawParticleBVH(FRigidTransform3(), Particle.Handle(), FColor::Silver, &ChaosSolverDebugDebugDrawSettings);
}
}