kloam/Assets/Scripts/MoveController.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[RequireComponent(typeof(BoxCollider))]
public class MoveController : MonoBehaviour
{
    public const float skinWidth = 0.015f;
    public int horizontalRayCount = 4;
    public int verticalRayCount = 4;

    new private BoxCollider collider;
    private RaycastOrigins raycastOrigins;
    private float horizontalRaySpacing;
    private float verticalRaySpacing;

    void Start() {
        collider = GetComponent<BoxCollider>();
    }

    void Update() {
        UpdateRaycastOrigins();
        CalculateRaySpacing();

        // bottom face
        for (int i = 0; i < verticalRayCount; i++) {
            for (int j = 0; j < verticalRayCount; j++) {
                Debug.DrawRay(raycastOrigins.bottomFrontLeft + Vector3.right * verticalRaySpacing * i - Vector3.back * verticalRaySpacing * j, Vector3.down, Color.red);
            }
        }
    }

    void UpdateRaycastOrigins() {
        Bounds bounds = collider.bounds;
        bounds.Expand(skinWidth * -2);

        raycastOrigins.bottomFrontLeft = new Vector3(bounds.min.x, bounds.min.y, bounds.min.z);  // 0 0 0
        raycastOrigins.bottomBackLeft = new Vector3(bounds.min.x, bounds.min.y, bounds.max.z);   // 0 0 1
        raycastOrigins.topFrontLeft = new Vector3(bounds.min.x, bounds.max.y, bounds.min.z);     // 0 1 0
        raycastOrigins.topBackLeft = new Vector3(bounds.min.x, bounds.max.y, bounds.max.z);      // 0 1 1

        raycastOrigins.bottomFrontRight = new Vector3(bounds.max.x, bounds.min.y, bounds.min.z); // 1 0 0
        raycastOrigins.bottomBackRight = new Vector3(bounds.max.x, bounds.min.y, bounds.max.z);  // 1 0 1
        raycastOrigins.topFrontRight = new Vector3(bounds.max.x, bounds.max.y, bounds.min.z);    // 1 1 0
        raycastOrigins.topBackRight = new Vector3(bounds.max.x, bounds.max.y, bounds.max.z);     // 1 1 1
    }

    void CalculateRaySpacing() {
        Bounds bounds = collider.bounds;
        bounds.Expand(skinWidth * -2);

        if (horizontalRayCount < 2) { horizontalRayCount = 2; }
        if (verticalRayCount < 2) { verticalRayCount = 2; }

        horizontalRaySpacing = bounds.size.y / (horizontalRayCount - 1);
        verticalRaySpacing = bounds.size.x / (verticalRayCount - 1);
    }

    struct RaycastOrigins {
        public Vector3 topBackLeft;
        public Vector3 topBackRight;
        public Vector3 topFrontLeft;
        public Vector3 topFrontRight;
        public Vector3 bottomBackLeft;
        public Vector3 bottomBackRight;
        public Vector3 bottomFrontLeft;
        public Vector3 bottomFrontRight;
    }
}