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Point Entity (DotEnt)

Less than 1 minute

Point Entity (DotEnt)

DotEnt represents a point entity in CAD, used to mark positions.

Overview

A point entity is the simplest graphical element, containing only a single position coordinate. The display style of points is controlled by system variables.

Constructor

import { DotEnt, Point2D } from 'vjcad';

// Shorthand syntax (recommended)
const dot1 = new DotEnt([100, 100]);

// With size parameter
const dot2 = new DotEnt([100, 100], 2);

// Point2D syntax
const dot3 = new DotEnt(new Point2D(100, 100));

dot1.setDefaults();

Shorthand Syntax

Both the constructor and the base property support coordinates in [x, y] array form.

Properties

PropertyTypeDescription
positionPoint2DThe position coordinate of the point

Methods

Geometric Transformations

import { DotEnt, Point2D } from 'vjcad';

const dot = new DotEnt([50, 50]);

// Shorthand syntax (recommended)
dot.move([0, 0], [100, 100]);     // Move
dot.rotate([0, 0], Math.PI / 4);  // Rotate (around a specified point)
dot.scale([0, 0], 2);             // Scale
dot.mirror([0, 0], [100, 0]);     // Mirror

Examples

Drawing a Point Grid

import { Engine, DotEnt, Point2D } from 'vjcad';

function drawPointGrid(
  startX: number, startY: number,
  rows: number, cols: number,
  spacing: number
) {
  const dots: DotEnt[] = [];
  
  for (let i = 0; i < rows; i++) {
    for (let j = 0; j < cols; j++) {
      const dot = new DotEnt(
        new Point2D(startX + j * spacing, startY + i * spacing)
      );
      dot.setDefaults();
      dots.push(dot);
    }
  }
  
  Engine.addEntities(dots);
}

// Draw a 5x5 point grid
drawPointGrid(0, 0, 5, 5, 20);

Next Steps