p.Chaos.Solver.DebugDrawTransforms

p.Chaos.Solver.DebugDrawTransforms

#Overview

name: p.Chaos.Solver.DebugDrawTransforms

This variable is created as a Console Variable (cvar).

It is referenced in 4 C++ source files.

#Summary

#Usage in the C++ source code

The purpose of p.Chaos.Solver.DebugDrawTransforms is to enable debug drawing of particle transforms in the Chaos physics solver. This setting is part of the debug visualization system for the Chaos physics engine in Unreal Engine 5.

The Chaos physics solver, which is part of the Experimental Chaos module in Unreal Engine 5, relies on this setting variable. It is used specifically in the debug drawing functionality of the physics solver.

The value of this variable is set through a console variable (CVar) system. It is initialized as an integer with a default value of 0 and can be changed at runtime using the console command “p.Chaos.Solver.DebugDrawTransforms”.

This variable interacts closely with its associated variable ChaosSolverDrawTransforms. 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 used during development and debugging. Enabling this feature may impact performance, so it should be disabled in release builds.

Best practices when using this variable include:

  1. Use it only when necessary for debugging physics issues.
  2. Remember to disable it when not needed to avoid performance impacts.
  3. Be aware that it draws particle transforms at the end of each frame when set to 1.

Regarding the associated variable ChaosSolverDrawTransforms:

The purpose of ChaosSolverDrawTransforms is identical to p.Chaos.Solver.DebugDrawTransforms. It’s an internal variable that directly controls the debug drawing of particle transforms.

This variable is used in the PostTickDebugDraw function of the FPBDRigidsSolver class. When set to 1, it triggers the drawing of particle transforms for all particles in the solver.

The value of ChaosSolverDrawTransforms is set through the console variable system, just like p.Chaos.Solver.DebugDrawTransforms.

Developers should treat ChaosSolverDrawTransforms the same way as p.Chaos.Solver.DebugDrawTransforms, as they are essentially the same variable used in different contexts within the Chaos solver code.

#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:151

Scope (from outer to inner):

file
namespace    Chaos
namespace    CVars

Source code excerpt:

		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."));
		FAutoConsoleVariableRef CVarChaosSolverDrawCCD(TEXT("p.Chaos.Solver.DebugDrawCCDInteractions"), ChaosSolverDrawCCDInteractions, TEXT("Draw CCD interactions."));
		FAutoConsoleVariableRef CVarChaosSolverDrawCCDThresholds(TEXT("p.Chaos.Solver.DebugDrawCCDThresholds"), ChaosSolverDrawCCDThresholds, TEXT("Draw CCD swept thresholds."));
		FAutoConsoleVariableRef CVarChaosSolverDrawShapesShapesStatic(TEXT("p.Chaos.Solver.DebugDraw.ShowStatics"), ChaosSolverDrawShapesShowStatic, TEXT("If DebugDrawShapes is enabled, whether to show static objects"));
		FAutoConsoleVariableRef CVarChaosSolverDrawShapesShapesKinematic(TEXT("p.Chaos.Solver.DebugDraw.ShowKinematics"), ChaosSolverDrawShapesShowKinematic, TEXT("If DebugDrawShapes is enabled, whether to show kinematic objects"));

#Associated Variable and Callsites

This variable is associated with another variable named ChaosSolverDrawTransforms. They share the same value. See the following C++ source code.

#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:124

Scope (from outer to inner):

file
namespace    Chaos
namespace    CVars

Source code excerpt:

		int32 ChaosSolverDebugDrawCollidingShapes = 0;
		int32 ChaosSolverDebugDrawBounds = 0;
		int32 ChaosSolverDrawTransforms = 0;
		int32 ChaosSolverDrawIslands = 0;
		int32 ChaosSolverDebugDrawIslandSleepState = 0;
		int32 ChaosSolverDrawCCDInteractions = 0;
		int32 ChaosSolverDrawCCDThresholds = 0;
		int32 ChaosSolverDrawShapesShowStatic = 1;
		int32 ChaosSolverDrawShapesShowKinematic = 1;

#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:151

Scope (from outer to inner):

file
namespace    Chaos
namespace    CVars

Source code excerpt:

		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."));
		FAutoConsoleVariableRef CVarChaosSolverDrawCCD(TEXT("p.Chaos.Solver.DebugDrawCCDInteractions"), ChaosSolverDrawCCDInteractions, TEXT("Draw CCD interactions."));
		FAutoConsoleVariableRef CVarChaosSolverDrawCCDThresholds(TEXT("p.Chaos.Solver.DebugDrawCCDThresholds"), ChaosSolverDrawCCDThresholds, TEXT("Draw CCD swept thresholds."));
		FAutoConsoleVariableRef CVarChaosSolverDrawShapesShapesStatic(TEXT("p.Chaos.Solver.DebugDraw.ShowStatics"), ChaosSolverDrawShapesShowStatic, TEXT("If DebugDrawShapes is enabled, whether to show static objects"));
		FAutoConsoleVariableRef CVarChaosSolverDrawShapesShapesKinematic(TEXT("p.Chaos.Solver.DebugDraw.ShowKinematics"), ChaosSolverDrawShapesShowKinematic, TEXT("If DebugDrawShapes is enabled, whether to show kinematic objects"));

#Loc: <Workspace>/Engine/Source/Runtime/Experimental/Chaos/Private/PBDRigidsSolver.cpp:2575

Scope (from outer to inner):

file
namespace    Chaos
function     void FPBDRigidsSolver::PostTickDebugDraw

Source code excerpt:

			DebugDraw::DrawParticleBounds(FRigidTransform3(), Particles.GetNonDisabledDynamicView(), Dt, &ChaosSolverDebugDebugDrawSettings);
		}
		if (ChaosSolverDrawTransforms == 1)
		{
			DebugDraw::DrawParticleTransforms(FRigidTransform3(), Particles.GetAllParticlesView(), &ChaosSolverDebugDebugDrawSettings);
		}
		if (ChaosSolverDrawIslands == 1)
		{
			DebugDraw::DrawConstraintGraph(FRigidTransform3(), GetEvolution()->GetIslandManager(), &ChaosSolverDebugDebugDrawSettings);