UI Line Renderer

Draws polylines in UI space, including the list-based variant.

Primitives primitives line renderer

Controls demonstrated: UI Line Renderer UI Line Renderer (List)

Overview

This folder collects several scenes that demonstrate drawing lines on a Canvas with the UI Line Renderer family of controls. They cover free-hand line drawing from pointer input, adding/clearing points at runtime, and animating an orbit path, using both the array-based UILineRenderer and the list-based UILineRendererList. Use these when you need to draw polylines, charts or dynamic paths in UI space.

Controls Featured

• UI Line Renderer — the LineDrawing and UILineRendererDemo scenes draw and animate lines by setting its Points array.
• UI Line Renderer (List) — the UILineRendererListDemo scene builds the same effects using its AddPoint/ClearPoints list API.

Scene Setup

1. Add the UI Extensions Samples sample to your project (open the package in the Unity Package Manager and import UI Extensions Samples), or copy Examples~/UILineRenderer/ into your project’s Assets/ folder.
2. Open one of the example scenes in that folder: LineDrawing, UILineRendererDemo, or UILineRendererListDemo.
3. Press Play.

What to Expect

In LineDrawing you draw lines directly with the mouse. The DrawLine script supports two modes: Drag and Draw, where dragging rubber-bands a line between the start and release points, and Click and Draw, where each click extends a continuous line that follows the cursor until you right-click or press Escape. The demo scenes also show an animated orbit where a UILineRenderer/UILineRendererList traces a circle (driven by the LineRendererOrbit/LineRendererOrbitList scripts) and a small UI object travels around that path. Input fields with a button let you add new points by X/Y value or clear the line entirely. Remember the line renderer’s RectTransform should sit at (0,0,0) for correct results.

Key Code Patterns

// UILineRenderer: replace the whole Points array
public void AddNewPoint()
{
    var point = new Vector2() { x = float.Parse(XValue.text), y = float.Parse(YValue.text) };
    var pointlist = new List<Vector2>(LineRenderer.Points);
    pointlist.Add(point);
    LineRenderer.Points = pointlist.ToArray();
}

// UILineRendererList: append/clear via the list API
public void AddNewPoint()
{
    var point = new Vector2() { x = float.Parse(XValue.text), y = float.Parse(YValue.text) };
    LineRenderer.AddPoint(point);
}