PhysicsShapeGroup2D.AddCircle

参数

返回值

int 返回形状在 PhysicsShapeGroup2D 中被添加到的形状索引。检索形状时，此索引用作主要引用。

说明

向形状组添加一个圆形（PhysicsShapeType2D.Circle）。

圆形由一个顶点（center）和一个围绕该顶点延伸的 radius 组成。这是在所有用例中使用时效率最高、内存占用最少的基元。

注意：圆形成一个闭合形状，并且有一个内部，因此物理查询等可以检测到其内部。

using UnityEngine;
using UnityEngine.Assertions;

public class Example : MonoBehaviour
{
    void Start()
    {
        CreateShape();
        GetShapeFromCollider();
    }

    // Create a custom shape.
    void CreateShape()
    {
        // Create a shape group.
        var shapeGroup = new PhysicsShapeGroup2D();

        // Add a Circle.
        var shapeIndex = shapeGroup.AddCircle
            (
                center: new Vector2(-2f, 3f),
                radius: 1f
            );

        // Fetch the actual shape created.
        var physicsShape = shapeGroup.GetShape(shapeIndex);

        // Validate what we created.
        Assert.AreEqual(PhysicsShapeType2D.Circle, physicsShape.shapeType);
        Assert.AreApproximatelyEqual(1f, physicsShape.radius);
        Assert.AreEqual(1, physicsShape.vertexCount);
    }

    // Get a physics shape from a Collider.
    void GetShapeFromCollider()
    {
        // Fetch the collider.
        var collider = GetComponent<CircleCollider2D>();

        // If the collider is not active and enabled then we'll get no shapes.
        // Let's just quit if not.
        if (!collider.isActiveAndEnabled)
            return;

        // Configure the collider.
        collider.radius = 1f;

        // Create a shape group.
        var shapeGroup = new PhysicsShapeGroup2D();

        // Get the collider shapes.
        collider.GetShapes(shapeGroup);

        // Fetch the actual shape.
        var physicsShape = shapeGroup.GetShape(0);

        // Validate what we retrieved.
        Assert.AreEqual(PhysicsShapeType2D.Circle, physicsShape.shapeType);
        Assert.AreApproximatelyEqual(1f, physicsShape.radius);
        Assert.AreEqual(1, physicsShape.vertexCount);
    }
}