Represents a trace entity in AutoCAD.

A trace is a 3D geometric object that represents a filled four-sided polygon. It is typically used to create trace-like shapes and can be visualized as a "filled polyline" with four vertices, where each edge connects two consecutive points.

This entity was more commonly used in earlier versions of AutoCAD, especially before the introduction of more advanced entities like solid and hatches. Today, it's not as commonly used since solid provides similar capabilities with more flexibility.

// Create a trace entity
const trace = new AcDbTrace();
trace.setPointAt(0, new AcGePoint3d(0, 0, 0));
trace.setPointAt(1, new AcGePoint3d(10, 0, 0));
trace.setPointAt(2, new AcGePoint3d(10, 5, 0));
trace.setPointAt(3, new AcGePoint3d(0, 5, 0));

// Access trace properties
console.log(`Elevation: ${trace.elevation}`);
console.log(`Thickness: ${trace.thickness}`);

Hierarchy (View Summary)

Constructors

  • Creates a new trace entity.

    This constructor initializes a trace with default values. All vertices are set to the origin, elevation is 0, and thickness is 1.

    Returns AcDbTrace

    const trace = new AcDbTrace();
    // Set the four vertices to create a rectangle
    trace.setPointAt(0, new AcGePoint3d(0, 0, 0));
    trace.setPointAt(1, new AcGePoint3d(10, 0, 0));
    trace.setPointAt(2, new AcGePoint3d(10, 5, 0));
    trace.setPointAt(3, new AcGePoint3d(0, 5, 0));

Accessors

  • get closed(): boolean
  • Gets whether this trace is closed.

    Traces are always closed entities, so this always returns true.

    Returns boolean

    Always true for traces

  • get database(): AcDbDatabase
  • Gets the database in which this object is resident.

    When an object isn't added to a database, this property returns the current working database. After it is added to a database, it will be set automatically. You should never set this value manually.

    Returns AcDbDatabase

    The database this object belongs to

    const db = obj.database;
    
  • set database(db: AcDbDatabase): void
  • Sets the database for this object.

    This is typically set automatically when the object is added to a database. Manual setting should be avoided unless you know what you're doing.

    Parameters

    Returns void

    obj.database = myDatabase;
    
  • get elevation(): number
  • Gets the elevation of this trace.

    The elevation is the distance of the trace's plane from the WCS origin along the Z-axis.

    Returns number

    The elevation value

    const elevation = trace.elevation;
    console.log(`Trace elevation: ${elevation}`);
  • set elevation(value: number): void
  • Sets the elevation of this trace.

    Parameters

    • value: number

      The new elevation value

    Returns void

    trace.elevation = 10;
    
  • get geometricExtents(): AcGeBox3d
  • Gets the geometric extents (bounding box) of this trace.

    Returns AcGeBox3d

    The bounding box that encompasses the entire trace

    const extents = trace.geometricExtents;
    console.log(`Trace bounds: ${extents.minPoint} to ${extents.maxPoint}`);
  • get layer(): string
  • Gets the name of the layer referenced by this entity.

    Returns string

    The layer name

    const layerName = entity.layer;
    
  • set layer(value: string): void
  • Sets the name of the layer for this entity.

    Parameters

    • value: string

      The new layer name

    Returns void

    entity.layer = 'MyLayer';
    
  • get lineStyle(): AcGiLineStyle
  • Gets the line style for this entity.

    This method returns the line style based on the entity's linetype and other properties.

    Returns AcGiLineStyle

    The line style object

    const lineStyle = entity.lineStyle;
    
  • get lineType(): string
  • Gets the name of the line type referenced by this entity.

    Returns string

    The linetype name

    const lineType = entity.lineType;
    
  • set lineType(value: string): void
  • Sets the name of the line type for this entity.

    Parameters

    • value: string

      The new linetype name

    Returns void

    entity.lineType = 'DASHED';
    
  • get linetypeScale(): number
  • Gets the line type scale factor of this entity.

    When an entity is first instantiated, its line type scale is initialized to an invalid value. When the entity is added to the database, if a linetype scale has not been specified for the entity, it is set to the database's current line type scale value.

    Returns number

    The linetype scale factor

    const scale = entity.linetypeScale;
    
  • set linetypeScale(value: number): void
  • Sets the line type scale factor for this entity.

    Parameters

    • value: number

      The new linetype scale factor

    Returns void

    entity.linetypeScale = 2.0;
    
  • get lineWeight(): number
  • Gets the line weight used by this entity.

    Returns number

    The line weight value

    const weight = entity.lineWeight;
    
  • set lineWeight(value: number): void
  • Sets the line weight for this entity.

    Parameters

    • value: number

      The new line weight value

    Returns void

    entity.lineWeight = 2;
    
  • get objectId(): string
  • Gets the object ID.

    AutoCAD uses 64-bit integers to represent handles, which exceed the maximum integer value of JavaScript. Therefore, strings are used to represent object handles.

    Returns string

    The object ID as a string

    const id = obj.objectId;
    console.log(`Object ID: ${id}`);
  • set objectId(value: string): void
  • Sets the object ID.

    Parameters

    • value: string

      The new object ID

    Returns void

    obj.objectId = 'new-object-id';
    
  • get ownerId(): string
  • Gets the object ID of the owner of this object.

    Returns string

    The owner object ID

    const ownerId = obj.ownerId;
    
  • set ownerId(value: string): void
  • Sets the object ID of the owner of this object.

    Parameters

    • value: string

      The new owner object ID

    Returns void

    obj.ownerId = 'parent-object-id';
    
  • get rgbColor(): number
  • Gets the RGB color of this entity after converting color index.

    This method handles the conversion of color indices (including ByLayer and ByBlock) to actual RGB colors. It resolves layer colors and block colors as needed.

    Returns number

    The RGB color value as a number

    const rgbColor = entity.rgbColor;
    console.log(`RGB: ${rgbColor.toString(16)}`);
  • get thickness(): number
  • Gets the thickness of this trace.

    The thickness is the trace's dimension along its normal vector direction (sometimes called the extrusion direction).

    Returns number

    The thickness value

    const thickness = trace.thickness;
    console.log(`Trace thickness: ${thickness}`);
  • set thickness(value: number): void
  • Sets the thickness of this trace.

    Parameters

    • value: number

      The new thickness value

    Returns void

    trace.thickness = 2.0;
    
  • get transparency(): number
  • Gets the transparency level of this entity.

    Returns number

    The transparency value (0-1, where 0 is opaque and 1 is fully transparent)

    const transparency = entity.transparency;
    
  • set transparency(value: number): void
  • Sets the transparency level of this entity.

    Parameters

    • value: number

      The transparency value (0-1, where 0 is opaque and 1 is fully transparent)

    Returns void

    entity.transparency = 0.5; // 50% transparent
    
  • get type(): string
  • Gets the type name of this entity.

    This method returns the entity type by removing the "AcDb" prefix from the constructor name.

    Returns string

    The entity type name

    const entity = new AcDbLine();
    console.log(entity.type); // "Line"
  • get visibility(): boolean
  • Gets whether this entity is visible.

    Returns boolean

    True if the entity is visible, false otherwise

    const isVisible = entity.visibility;
    
  • set visibility(value: boolean): void
  • Sets whether this entity is visible.

    Parameters

    • value: boolean

      True to make the entity visible, false to hide it

    Returns void

    entity.visibility = false; // Hide the entity
    

Methods

  • Closes the object.

    All changes made to the object since it was opened are committed to the database, and a "closed" notification is sent. This method can be overridden by subclasses to provide specific cleanup behavior.

    Returns void

    obj.close();
    
  • Gets the value of the specified attribute.

    This method will throw an exception if the specified attribute doesn't exist. Use getAttrWithoutException() if you want to handle missing attributes gracefully.

    Parameters

    • attrName: string

      The name of the attribute to retrieve

    Returns any

    The value of the specified attribute

    When the specified attribute doesn't exist

    try {
    const value = obj.getAttr('objectId');
    } catch (error) {
    console.error('Attribute not found');
    }
  • Gets the value of the specified attribute without throwing an exception.

    This method returns undefined if the specified attribute doesn't exist, making it safer for optional attributes.

    Parameters

    • attrName: string

      The name of the attribute to retrieve

    Returns any

    The value of the specified attribute, or undefined if it doesn't exist

    const value = obj.getAttrWithoutException('optionalAttribute');
    if (value !== undefined) {
    // Use the value
    }
  • Gets the color of the layer this entity belongs to.

    This method retrieves the color from the layer table for the layer this entity belongs to.

    Returns null | AcCmColor

    The layer color, or undefined if the layer doesn't exist

    const layerColor = entity.getLayerColor();
    
  • Gets the point at the specified index in this trace.

    The index can be 0, 1, 2, or 3, representing the four vertices of the trace. If the index is out of range, it returns the first or last vertex accordingly.

    Parameters

    • index: number

      The index (0-3) of the vertex to get

    Returns AcGePoint3d

    The point at the specified index in WCS coordinates

    const point0 = trace.getPointAt(0);
    const point1 = trace.getPointAt(1);
    console.log(`Vertex 0: ${point0.x}, ${point0.y}, ${point0.z}`);
  • Sets the point at the specified index in this trace.

    The index must be 0, 1, 2, or 3, representing the four vertices of the trace. If the index is out of range, it sets the first or last vertex accordingly.

    Parameters

    • index: number

      The index (0-3) of the vertex to set

    • point: AcGeVectorLike

      The new point in WCS coordinates

    Returns undefined | AcGePoint3d

    trace.setPointAt(0, new AcGePoint3d(0, 0, 0));
    trace.setPointAt(1, new AcGePoint3d(10, 0, 0));
    trace.setPointAt(2, new AcGePoint3d(10, 5, 0));
    trace.setPointAt(3, new AcGePoint3d(0, 5, 0));
  • Gets the grip points for this trace.

    Grip points are control points that can be used to modify the trace. For a trace, the grip points are all four vertices.

    Returns AcGePoint3d[]

    Array of grip points (all four vertices)

    const gripPoints = trace.subGetGripPoints();
    // gripPoints contains all four vertices of the trace
  • Gets the object snap points for this entity.

    Object snap points are the points that can be used for precise positioning when drawing or editing. This method should be overridden by subclasses to provide entity-specific snap points.

    Parameters

    Returns void

    const snapPoints: AcGePoint3d[] = [];
    entity.subGetOsnapPoints(AcDbOsnapMode.Endpoint, 0, pickPoint, lastPoint, snapPoints);
  • Transforms this entity by the specified matrix.

    This method applies a geometric transformation to the entity. Subclasses should override this method to provide entity-specific transformation behavior.

    Parameters

    Returns this

    This entity after transformation

    const matrix = AcGeMatrix3d.translation(10, 0, 0);
    entity.transformBy(matrix);