HeavenStudio/Assets/Plugins/com.unity.uiextensions/Runtime/Scripts/Utilities/UILineConnector.cs
2022-01-05 19:11:33 -05:00

86 lines
3 KiB
C#

/// Credit Alastair Aitchison
/// Sourced from - https://bitbucket.org/UnityUIExtensions/unity-ui-extensions/issues/123/uilinerenderer-issues-with-specifying
namespace UnityEngine.UI.Extensions
{
[AddComponentMenu("UI/Extensions/UI Line Connector")]
[RequireComponent(typeof(UILineRenderer))]
[ExecuteInEditMode]
public class UILineConnector : MonoBehaviour
{
// The elements between which line segments should be drawn
public RectTransform[] transforms;
private Vector3[] previousPositions;
private RectTransform canvas;
private RectTransform rt;
private UILineRenderer lr;
private void Awake()
{
canvas = GetComponentInParent<RectTransform>().GetParentCanvas().GetComponent<RectTransform>();
rt = GetComponent<RectTransform>();
lr = GetComponent<UILineRenderer>();
}
// Update is called once per frame
void Update()
{
if (transforms == null || transforms.Length < 1)
{
return;
}
//Performance check to only redraw when the child transforms move
if (previousPositions != null && previousPositions.Length == transforms.Length)
{
bool updateLine = false;
for (int i = 0; i < transforms.Length; i++)
{
if (!updateLine && previousPositions[i] != transforms[i].position)
{
updateLine = true;
}
}
if (!updateLine) return;
}
// Get the pivot points
Vector2 thisPivot = rt.pivot;
Vector2 canvasPivot = canvas.pivot;
// Set up some arrays of coordinates in various reference systems
Vector3[] worldSpaces = new Vector3[transforms.Length];
Vector3[] canvasSpaces = new Vector3[transforms.Length];
Vector2[] points = new Vector2[transforms.Length];
// First, convert the pivot to worldspace
for (int i = 0; i < transforms.Length; i++)
{
worldSpaces[i] = transforms[i].TransformPoint(thisPivot);
}
// Then, convert to canvas space
for (int i = 0; i < transforms.Length; i++)
{
canvasSpaces[i] = canvas.InverseTransformPoint(worldSpaces[i]);
}
// Calculate delta from the canvas pivot point
for (int i = 0; i < transforms.Length; i++)
{
points[i] = new Vector2(canvasSpaces[i].x, canvasSpaces[i].y);
}
// And assign the converted points to the line renderer
lr.Points = points;
lr.RelativeSize = false;
lr.drivenExternally = true;
previousPositions = new Vector3[transforms.Length];
for (int i = 0; i < transforms.Length; i++)
{
previousPositions[i] = transforms[i].position;
}
}
}
}