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🛠️ Debug Assist

Short Description

Debug Assist provides a suite of high-fidelity visual debugging tools to help developers visualize traces, collisions, and spatial data in real-time.

Long Description

Debug Assist goes beyond standard Unreal debug drawing by providing persistent, styled, and state-aware visualizations. It includes specialized nodes for visualizing complex traces (including swept spheres), projected circles that wrap around geometry, and diamond markers that always face the camera. All debug visuals can be cleared at once using a single command, making it an essential tool for debugging gameplay logic and world interaction.

🚀 Features

  • Persistent & Duration Based: Draw shapes that stay for a single frame, a few seconds, or indefinitely.
  • State-Aware Points: Draw points that change color and size based on a Success/Failure/Warning state.
  • Projected Shapes: Draw circles that "shrink-wrap" onto uneven geometry.
  • Trace Visualization: Deep integration with FHitResult to draw impact points, normals, and swept shapes.
  • Global Cleanup: Quickly remove all debug visuals with ClearDebugAssistGhosts.

📚 Usage Examples

UGorgeousDebugAssistBlueprintFunctionLibrary::DrawDebugAssistLine(GetWorld(), Start, End, FLinearColor::Red, 5.0f);

Use the Draw Debug Assist Trace node after a Line or Sphere Trace to visualize exactly what was hit and where.

DrawDebugAssistLine

Draws a simple debug line between two points.

Parameter Name Type Description
Start FVector Starting location.
End FVector Ending location.
Color FLinearColor Line color.
Duration float Visibility time in seconds.

DrawDebugAssistSphere

Draws a wireframe or filled sphere at a location.

Parameter Name Type Description
Center FVector Center point.
Radius float Sphere radius.
bWireframe bool Whether to draw wireframe.
bFilled bool Whether to draw a solid sphere.

DrawDebugAssistTrace

Visualizes a trace path and its swept volume (for sphere traces).

Parameter Name Type Description
Start FVector Trace start.
End FVector Trace end.
Radius float Sphere radius (if applicable).

DrawDebugAssistProjectedCircle

Draws a circle that projects onto geometry faces to "wrap" around corners. Excellent for floor markers.

Parameter Name Type Description
Location FVector Center of the projection.
Radius float Circle radius.
Normal FVector Projection plane normal (usually Up).

ClearDebugAssistGhosts

Immediately removes all active debug assist visuals from the world.

Best Practices

  • Avoid Per-Frame Overload: Drawing hundreds of persistent debug shapes per frame can severely impact performance. Use short durations for frequently updated logic.
  • State Coloring: Use the state-aware point functions to quickly identify branching logic results (e.g., Green for a successful interaction check, Red for a failure).
  • Projected Markers: Use DrawDebugAssistProjectedCircle for player movement destinations or area-of-effect indicators during development.

Troubleshooting

  • Z-Fighting: If debug shapes are flickering against geometry, try slightly increasing the Thickness or adjusting the Radius.
  • Not Visible: Check if the CVar for debug drawing is enabled in your project's console (Display.DebugLines 1).
  • Persistent Lines Remaining: If lines won't disappear, use the ClearDebugAssistGhosts node or console command.