CharacterController.cs

using System;
using Duality;
using Duality.Components.Physics;
using Duality.Components.Renderers;
using Duality.Drawing;
using Duality.Editor;

namespace mfep.Duality.Snippets
{
	[RequiredComponent (typeof(SpriteRenderer))]
	public class CharacterController : Component
	{
		[Flags]
		public enum Sides
		{
			None        = 0b0000,
			Top         = 0b0001,
			Right       = 0b0010,
			Bottom      = 0b0100,
			Left        = 0b1000,

			TopRight    = 0b0011,
			BottomRight = 0b0110,
			TopLeft     = 0b1001,
			BottomLeft  = 0b1100
		}

		public int   RayCount  { get; set; }         = 3;
		public float Skin      { get; set; }         = 1f;
		public bool  Visualize { get; set; }         = false;

		[EditorHintFlags(MemberFlags.ReadOnly)]
		public Sides Collision { get; private set; } = Sides.None;

		public void Move (Vector2 deltaPos)
		{
			Collision = Sides.None;

			MoveX (deltaPos);
			MoveY (deltaPos);
		}

		private void MoveX (Vector2 deltaPos)
		{
			if (!(MathF.Abs (deltaPos.X) > 0.0f)) return;

			var bounds = GameObj.GetComponent<SpriteRenderer> ().Rect.WithOffset(GameObj.Transform.Pos.Xy);
			var dx = Vector2.UnitX * deltaPos.X;
			var dirX = deltaPos.X > 0.0f ? 1.0f : -1.0f;
			var skinV = Vector2.UnitX * dirX * this.Skin;

			var topCenter = bounds.Center - Vector2.UnitY * (bounds.H * 0.5f - this.Skin);
			var height = bounds.H - 2.0f * this.Skin;
			var rayDivision = Vector2.UnitY * height / (this.RayCount - 1.0f);
			var offs = Vector2.UnitX * (bounds.W * 0.5f * dirX) - skinV;

			var minFraction = 1.0f;
			var hit = false;
			var frac = 1.0f;
			for (int i = 0; i < RayCount; i++)
			{
				var origin = topCenter + i * rayDivision + offs;

				if (RigidBody.RayCast(origin, origin + dx + skinV, data => 1.0f, out RayCastData firstHit))
				{
					hit = true;
					frac = firstHit.Fraction;
					minFraction = MathF.Min(minFraction, firstHit.Fraction);
				}
				if (this.Visualize)
				{
					VisualLog.Default.BaseColor = hit ? ColorRgba.Red : ColorRgba.White;
					VisualLog.Default.DrawVector (new Vector3 (origin), (dx + skinV) * frac);
				}
			}

			var xMove = (dx + skinV) * minFraction - skinV;
			GameObj.Transform.MoveByAbs(xMove);

			if (hit) {
				var side = dirX > 0.0f ? Sides.Right : Sides.Left;
				Collision |= side;
			}
		}

		private void MoveY (Vector2 deltaPos)
		{
			if (!(MathF.Abs(deltaPos.Y) > 0.0f)) return;

			var bounds = GameObj.GetComponent<SpriteRenderer>().Rect.WithOffset(GameObj.Transform.Pos.Xy);
			var dy = Vector2.UnitY * deltaPos.Y;
			var dirY = deltaPos.Y > 0.0f ? 1.0f : -1.0f;
			var skinV = Vector2.UnitY * dirY * this.Skin;

			var leftCenter = bounds.Center - Vector2.UnitX * (bounds.W * 0.5f - this.Skin);
			var width = bounds.W - 2.0f * this.Skin;
			var rayDivision = Vector2.UnitX * width / (this.RayCount - 1.0f);
			var offs = Vector2.UnitY * (bounds.H * 0.5f * dirY) - skinV;

			var minFraction = 1.0f;
			var hit = false;
			var frac = 1.0f;
			for (int i = 0; i < RayCount; i++)
			{
				var origin = leftCenter + i * rayDivision + offs;

				if (RigidBody.RayCast(origin, origin + dy + skinV, data => 1.0f, out RayCastData firstHit))
				{
					hit = true;
					frac = firstHit.Fraction;
					minFraction = MathF.Min(minFraction, firstHit.Fraction);
				}
				if (this.Visualize)
				{
					VisualLog.Default.BaseColor = hit ? ColorRgba.Red : ColorRgba.White;
					VisualLog.Default.DrawVector (new Vector3 (origin), (dy + skinV) * frac);
				}
			}

			var yMove = (dy + skinV) * minFraction - skinV;
			GameObj.Transform.MoveByAbs(yMove);

			if (hit) {
				var side = dirY > 0.0f ? Sides.Bottom : Sides.Top;
				Collision |= side;
			}
		}
	}
}