Note: this feature requires SaintsDraw 4.0.5 installed

Draw an arrow between different objects. The decorated field need to be a GameObject/Component or a Vector3/Vector2, or a list/array of them.

Parameters:

• string start = null: where does the arrow start. null for the current field.
• int startIndex = 0: when start is not null, and the start is a list/array, specify the index of the start.
• string startSpace = "this": the containing space. "this" means using the current target, null means using the world space, otherwise means using a callback or a field value
• string end = null: where does the arrow end. null for the current field.
• int endIndex = 0: when end is not null, and the end is a list/array, specify the index of the end.
• string endSpace = "this": the containing space. "this" means using the current target, null means using the world space, otherwise means using a callback or a field value
• EColor eColor = EColor.White: color
• float alpha = 1f: the alpha of the color. Not works with color.
• string color = null: the color of the line. If it starts with #, use html hex color, otherwise use as a callback. This overrides the eColor.
• float dotted = -1f: when >=0, draw dotted line instead.
• float headLength = 0.5f: the length of the arrow head.
• float headAngle = 20.0f: the angle of the arrow head.

Specially

1. using on an array/list without specifying start and end will arrow-connect the element from first to last.
2. startIndex & endIndex can be negative, which means to count from the end. -1 means the last element.

A complex showcase:

using SaintsField;

[SerializeField, GetComponent, DrawLabel("Entrance"),
 // connect this to worldPos[0]
 SaintsArrow(end: nameof(worldPos), endIndex: 0, endSpace: Space.Self),
] private GameObject entrance;

[
    // connect every element in the list
    SaintsArrow(color: EColor.Green, startSpace: Space.Self, headLength: 0.1f),
    // connect every element to the `centerPoint`
    SaintsArrow(start: nameof(centerPoint), color: EColor.Red, startSpace: Space.Self, endSpace: Space.Self, headLength: 0.1f, colorAlpha: 0.4f),

    PositionHandle,
    DrawLabel("
quot; + nameof(PosIndexLabel)),
]
public Vector3[] worldPos;

[DrawLabel("Center"), PositionHandle] public Vector3 centerPoint;

[DrawLabel("Exit"), GetComponentInChildren(excludeSelf: true), PositionHandle,
 // connect worldPos[0] to this
 SaintsArrow(start: nameof(worldPos), startIndex: -1, startSpace: Space.Self),
] public Transform exit;

private string PosIndexLabel(Vector3 pos, int index) => 
quot;[{index}]\n{pos}";