Implementation:CARLA simulator Carla DebugShape

Knowledge Sources	CARLA
Domains	Debug Visualization, RPC Serialization
Last Updated	2026-02-15 05:00 GMT

Overview

DebugShape is an RPC-serializable class that represents a debug drawing primitive (point, line, arrow, box, or string) that can be rendered in the CARLA simulation viewport.

Description

Defined in the carla::rpc namespace, this class uses a std::variant to hold one of five primitive shape types:

• Point: a location with a size
• Line: two endpoints with a thickness
• Arrow: a line with an arrow head size
• Box: a bounding box with rotation and thickness
• String: a location with text and shadow option

Each shape has a color (default red: 255,0,0), a life_time in seconds (-1.0 for permanent), and a persistent_lines flag (default true). All types are individually MsgPack-serializable, and the variant-based primitive is serialized as part of the top-level MSGPACK_DEFINE_ARRAY.

Usage

Use this type to send debug visualization commands from the client to the server for rendering points, lines, arrows, boxes, or text strings in the 3D viewport.

Code Reference

Source Location

• Repository: CARLA
• File: LibCarla/source/carla/rpc/DebugShape.h

Signature

namespace carla {
namespace rpc {

  class DebugShape {
  public:
    struct Point { geom::Location location; float size; };
    struct Line  { geom::Location begin; geom::Location end; float thickness; };
    struct Arrow { Line line; float arrow_size; };
    struct Box   { geom::BoundingBox box; geom::Rotation rotation; float thickness; };
    struct String { geom::Location location; std::string text; bool draw_shadow; };

    std::variant<Point, Line, Arrow, Box, String> primitive;
    Color color = {255u, 0u, 0u};
    float life_time = -1.0f;
    bool persistent_lines = true;

    MSGPACK_DEFINE_ARRAY(primitive, color, life_time, persistent_lines);
  };

} // namespace rpc
} // namespace carla

Import

#include "carla/rpc/DebugShape.h"

I/O Contract

Field	Type	Default	Description
primitive	std::variant<Point, Line, Arrow, Box, String>	--	The shape to render
color	Color	{255, 0, 0}	RGB color for the shape
life_time	float	-1.0f	Duration in seconds (-1 = permanent)
persistent_lines	bool	true	Whether lines persist across frames

Usage Examples

#include "carla/rpc/DebugShape.h"

carla::rpc::DebugShape shape;
shape.primitive = carla::rpc::DebugShape::Point{
    carla::geom::Location(10.0f, 20.0f, 1.0f), 0.5f
};
shape.color = {0u, 255u, 0u}; // green
shape.life_time = 5.0f;       // 5 seconds

// Send shape to server for debug rendering

Related Pages

• Environment:CARLA_simulator_Carla_Simulation_Runtime